:root {
  /* ── Light: warm cream, premium indigo accent ── */
  --bg: #f5f2ec;
  --surface: #ffffff;
  --surface2: #eeeae2;
  --border: #dfd9cf;
  --text: #1a1510;
  --muted: #857d73;
  --accent: #6366f1;       /* premium indigo-violet */
  --accent-light: #eef2ff;
  --accent-hover: #4f46e5;
  --yellow: #fdf3d6;        /* warm amber highlight */
  --yellow-border: #b5840a; /* rich amber underline */
  --yellow-active: #f8e5a8;
  --blue-bg: #eef3f7;
  --blue-border: #8aafc8;
  --green: #178a42;
  --green-light: #d5f0e0;
  --red: #c0392b;
  --red-light: #fae0dc;
  --orange: #c0622a;
  --orange-light: #faeadc;
  --shadow-sm: 0 1px 4px rgba(26,21,16,.07), 0 1px 2px rgba(26,21,16,.04);
  --shadow-md: 0 4px 18px rgba(26,21,16,.09), 0 1px 4px rgba(26,21,16,.05);
  --shadow-lg: 0 8px 40px rgba(26,21,16,.13);
  --shadow-card: 0 4px 28px rgba(99,102,241,.08), 0 1px 4px rgba(26,21,16,.06);
  --sw: 280px;
  --story-size: 17px;
}
[data-theme="dark"] {
  /* ── Dark: deep indigo-black, easy on eyes ── */
  --bg: #0f0e17;
  --surface: #17162a;
  --surface2: #1e1c38;
  --border: #2e2c50;
  --text: #e8e8ff;
  --muted: #8888b8;
  --accent: #818cf8;
  --accent-light: #1e1b4b;
  --accent-hover: #a5b4fc;
  --yellow: #271f08;
  --yellow-border: #a07818;
  --yellow-active: #332810;
  --blue-bg: #141d24;
  --blue-border: #3a5a78;
  --green: #40c870;
  --green-light: #0a2214;
  --red: #e07060;
  --red-light: #2e1210;
  --orange: #d4804a;
  --orange-light: #2a1810;
  --shadow-card: 0 4px 28px rgba(0,0,0,.45), 0 1px 4px rgba(0,0,0,.3);
}
[data-theme="purple"] {
  /* ── Purple: soft lavender, rich violet accents ── */
  --bg: #f2efff;
  --surface: #fdfcff;
  --surface2: #e9e4ff;
  --border: #d2c9f5;
  --text: #1b1140;
  --muted: #7b6ea8;
  --accent: #7c3aed;
  --accent-light: #f0ebff;
  --accent-hover: #6d28d9;
  --yellow: #fdf4ff;
  --yellow-border: #a855f7;
  --yellow-active: #f3e8ff;
  --blue-bg: #eef0ff;
  --blue-border: #8b91d4;
  --green: #16a34a;
  --green-light: #dcfce7;
  --red: #dc2626;
  --red-light: #fee2e2;
  --orange: #c2410c;
  --orange-light: #ffedd5;
  --shadow-sm: 0 1px 4px rgba(124,58,237,.08), 0 1px 2px rgba(30,18,69,.04);
  --shadow-md: 0 4px 18px rgba(124,58,237,.10), 0 1px 4px rgba(30,18,69,.05);
  --shadow-card: 0 4px 28px rgba(124,58,237,.12), 0 1px 4px rgba(30,18,69,.06);
}
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

/* Lock page-level scroll bounce on iOS — only inner containers should bounce */
html, body { height: 100%; overflow: hidden; overscroll-behavior: none; }

/* Subtle SVG noise texture on bg */
body {
  font-family: 'Inter', sans-serif;
  background-color: var(--bg);
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='200' height='200'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.75' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='200' height='200' filter='url(%23n)' opacity='0.03'/%3E%3C/svg%3E");
  color: var(--text); min-height: 100vh; font-size: 15px;
  transition: background-color 0.3s, color 0.3s;
}
@media (prefers-color-scheme: dark) {
  /* Only apply auto-dark when no explicit theme has been chosen */
  :root:not([data-theme="light"]):not([data-theme="purple"]):not([data-theme="dark"]) {
    --bg: #0f0e17; --surface: #17162a; --surface2: #1e1c38; --border: #2e2c50;
    --text: #e8e8ff; --muted: #8888b8;
    --accent: #818cf8; --accent-light: #1e1b4b; --accent-hover: #a5b4fc;
    --yellow: #271f08; --yellow-border: #a07818; --yellow-active: #332810;
    --blue-bg: #141d24; --blue-border: #3a5a78;
    --green: #40c870; --green-light: #0a2214;
    --red: #e07060; --red-light: #2e1210;
    --orange: #d4804a; --orange-light: #2a1810;
    --shadow-card: 0 4px 28px rgba(0,0,0,.45), 0 1px 4px rgba(0,0,0,.3);
  }
}

/* ── THEME TOGGLE ────────────────────────────────────────────────────── */
.dark-toggle {
  height: 32px; min-width: 32px; padding: 0 10px;
  border-radius: 8px; border: 1px solid var(--border);
  background: none; cursor: pointer;
  display: flex; align-items: center; gap: 5px;
  font-size: 13px; font-weight: 600; font-family: 'Inter', sans-serif;
  color: var(--muted); transition: all 0.15s; white-space: nowrap;
}
.dark-toggle:hover { background: var(--surface2); color: var(--text); border-color: var(--accent); }
.dark-toggle .theme-icon { font-size: 14px; line-height: 1; }
.dark-toggle .theme-label { font-size: 11px; letter-spacing: 0.2px; }

/* ── STREAK COUNTER ──────────────────────────────────────────────────── */
.streak-wrap { display: flex; align-items: center; gap: 5px; font-size: 11px; font-weight: 600; color: #b45309; }
.streak-flame { font-size: 14px; }
.streak-days { font-variant-numeric: tabular-nums; }

/* ── SIDEBAR DEPTH ───────────────────────────────────────────────────── */
.sidebar {
  background: var(--surface);
  border-right: 1px solid var(--border);
  display: flex; flex-direction: column; overflow: hidden;
  transition: transform 0.32s cubic-bezier(.25,1.4,.5,1);
  box-shadow: inset -1px 0 0 rgba(255,255,255,.4);
}

header {
  position: fixed; top: 0; left: 0; right: 0; z-index: 100;
  height: 44px; background: var(--surface); border-bottom: 1px solid var(--border);
  display: flex; align-items: center; justify-content: space-between; padding: 0 14px;
  box-shadow: 0 1px 0 rgba(255,255,255,.6) inset, 0 1px 8px rgba(26,21,16,.04);
}
header::after {
  content: '';
  position: absolute; bottom: -1px; left: 0; right: 0; height: 2px;
  background: linear-gradient(90deg, var(--accent) 0%, var(--accent-light) 40%, transparent 70%);
  opacity: 0.5;
  pointer-events: none;
}
.hd-left { display: flex; align-items: center; gap: 8px; }
.menu-btn { display: none; width: 32px; height: 32px; border-radius: 7px; background: transparent; border: none; cursor: pointer; font-size: 17px; align-items: center; justify-content: center; color: var(--muted); flex-shrink: 0; }
.menu-btn:hover { background: var(--surface2); color: var(--text); }
.hd-logo-mobile { display: none; font-family: 'Lora', serif; font-size: 16px; font-weight: 600; color: var(--accent); letter-spacing: -0.2px; }
.kokoro-status { display: flex; align-items: center; gap: 5px; font-size: 11px; color: var(--muted); }
.status-dot { width: 6px; height: 6px; border-radius: 50%; background: #d1d5db; }
.status-dot.ok { background: #22c55e; }

.layout { display: grid; grid-template-columns: var(--sw) 1fr; height: calc(100vh - 44px); margin-top: 44px; }

.sidebar-top { padding: 14px 16px 12px; border-bottom: 1px solid var(--border); }
.sidebar-logo { display: flex; align-items: center; gap: 8px; margin-bottom: 2px; }
.sidebar-logo-mark { flex-shrink: 0; }
.sidebar-logo-text { font-family: 'Lora', serif; font-size: 16px; font-weight: 500; color: var(--accent); letter-spacing: 0.3px; }
.sidebar-logo-dot { display: none; }
.sidebar-label { font-size: 10px; letter-spacing: 0.8px; font-weight: 500; color: var(--muted); margin-top: 3px; }
.chapter-list { flex: 1; overflow-y: auto; padding: 0; -webkit-overflow-scrolling: touch; overscroll-behavior-y: contain; }
.ch-item { display: flex; align-items: center; gap: 10px; padding: 11px 16px 11px 20px; cursor: pointer; transition: background 0.12s; border-bottom: 1px solid var(--border); position: relative; }
.ch-item:hover { background: var(--surface2); }
.story-chapters .ch-item:last-child { border-bottom: none; }
.ch-item.active { background: var(--accent-light); padding-left: 17px; border-left: 3px solid var(--accent); }
.ch-num { font-size: 10px; font-weight: 600; color: var(--muted); min-width: 18px; flex-shrink: 0; font-variant-numeric: tabular-nums; }
.ch-item.active .ch-num { color: var(--accent); }
.ch-info { flex: 1; min-width: 0; }
.ch-name { font-size: 13px; font-weight: 500; line-height: 1.35; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; color: var(--text); }
/* badges hidden by default, shown on hover and active */
.ch-meta { display: flex; gap: 4px; margin-top: 3px; opacity: 0; transition: opacity 0.15s; height: 0; overflow: hidden; }
.ch-item:hover .ch-meta, .ch-item.active .ch-meta { opacity: 1; height: auto; }
.ch-badge { display: inline-block; font-size: 10px; padding: 1px 5px; border-radius: 20px; background: var(--surface2); color: var(--muted); }
.ch-item.active .ch-badge { background: var(--accent); color: white; }
.ch-due { display: inline-block; font-size: 10px; padding: 1px 5px; border-radius: 20px; background: var(--orange-light); color: var(--orange); }
.sidebar-footer { padding: 10px; border-top: 1px solid var(--border); }
.all-srs-btn { width: 100%; padding: 10px; border: 1px solid var(--accent-light); background: var(--accent-light); border-radius: 9px; font-family: 'Inter', sans-serif; font-size: 12px; font-weight: 600; color: var(--accent); cursor: pointer; transition: all 0.15s; letter-spacing: 0.2px; }
.all-srs-btn:hover { background: linear-gradient(135deg, var(--accent), var(--accent-hover)); color: white; border-color: transparent; transform: translateY(-1px); box-shadow: 0 4px 12px rgba(26,122,69,.3); }

/* Story accordion */
.story-group { border-bottom: 1px solid var(--border); }
.story-group:last-child { border-bottom: none; }
.story-header { display: flex; align-items: center; justify-content: space-between; padding: 11px 14px 11px 12px; cursor: pointer; user-select: none; transition: background 0.12s; gap: 8px; }
.story-header:hover { background: var(--surface2); }
.story-header-left { display: flex; flex-direction: column; gap: 2px; min-width: 0; }
.story-name { font-size: 13px; font-weight: 600; color: var(--text); white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.story-meta { font-size: 10px; color: var(--muted); }
.story-chevron { font-size: 9px; color: var(--muted); transition: transform 0.2s; flex-shrink: 0; opacity: 0.6; }
.story-group.open .story-chevron { transform: rotate(180deg); }
.story-chapters { overflow: hidden; max-height: 0; transition: max-height 0.28s cubic-bezier(.4,0,.2,1); }
.story-group.open .story-chapters { max-height: 1200px; }
.story-group.open > .story-header { background: var(--accent-light); }
.story-group.open > .story-header .story-name { color: var(--accent); }
.story-group.open > .story-header .story-chevron { color: var(--accent); opacity: 1; }

.main {
  overflow-y: auto;
  padding: 28px 36px;
  -webkit-overflow-scrolling: touch;
  overscroll-behavior-y: contain;
  scroll-behavior: smooth;
}
.empty { display: flex; flex-direction: column; align-items: center; justify-content: center; height: 100%; gap: 12px; text-align: center; color: var(--muted); }
.empty-icon { font-size: 40px; opacity: 0.2; margin-bottom: 4px; }
.empty h3 { font-family: 'Lora', serif; font-size: 22px; color: var(--text); font-weight: 500; }
.empty p { font-size: 13px; max-width: 260px; line-height: 1.75; color: var(--muted); }

.chapter-view { max-width: 660px; }

/* ── CHAPTER HERO HEADER ─────────────────────────────────────────────── */
.chapter-header {
  padding: 28px 32px 26px;
  margin-bottom: 28px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 14px;
  box-shadow: 0 2px 12px rgba(0,0,0,.04), 0 1px 3px rgba(0,0,0,.03);
  position: relative;
  overflow: hidden;
}
/* Vibrant green accent stripe at top */
.chapter-header::before {
  content: '';
  position: absolute; top: 0; left: 0; right: 0; height: 4px;
  background: linear-gradient(90deg, var(--accent), var(--accent-light) 60%, transparent);
}
.ch-eyebrow {
  font-size: 10px; text-transform: uppercase; letter-spacing: 1.5px;
  font-weight: 700; color: var(--accent); margin-bottom: 10px;
  display: flex; align-items: center; gap: 8px;
}
.ch-eyebrow::after {
  content: ''; flex: 1; max-width: 40px; height: 1px;
  background: var(--accent); opacity: 0.3;
}
.ch-title {
  font-family: 'Lora', serif; font-size: 28px; font-weight: 600;
  line-height: 1.25; color: var(--text); margin-bottom: 14px;
  letter-spacing: -0.3px;
}
.ch-meta-row {
  display: flex; align-items: center; gap: 12px; flex-wrap: wrap;
}
.ch-meta-pill {
  font-size: 11px; color: var(--muted); background: var(--surface2);
  padding: 3px 9px; border-radius: 20px; border: 1px solid var(--border);
}
/* Streak badge in header */
.streak-badge {
  display: flex; align-items: center; gap: 4px;
  font-size: 11px; font-weight: 600; color: #d97706;
  background: #fef3c0; border: 1px solid #fde68a;
  padding: 3px 9px; border-radius: 20px; margin-left: auto;
}

/* Underline tabs — cleaner, editorial feel */
.tabs { display: flex; gap: 0; background: none; padding: 0; border-radius: 0; width: 100%; margin-bottom: 0; border-bottom: 1px solid var(--border); }
.tab { flex: none; padding: 8px 16px; border-radius: 0; font-size: 12px; font-weight: 500; cursor: pointer; transition: all 0.15s; color: var(--muted); border: none; background: none; font-family: 'Inter', sans-serif; white-space: nowrap; text-align: center; border-bottom: 2px solid transparent; margin-bottom: -1px; letter-spacing: 0.1px; }
.tab:hover { color: var(--text); }
.tab.active { color: var(--accent); border-bottom-color: var(--accent); font-weight: 600; }
#tabBody { animation: tabFadeIn 0.18s ease both; margin-top: 22px; }

/* ── READING WELL ────────────────────────────────────────────────────── */
.story-box {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 32px 36px 36px;
  margin-bottom: 0;
  box-shadow: 0 2px 20px rgba(26,122,69,.05), 0 1px 4px rgba(26,21,16,.04), 0 0 0 1px rgba(255,255,255,.8) inset;
  position: relative;
}
.story-box::before {
  content: '';
  position: absolute; top: 0; left: 0; right: 0; height: 1px;
  background: linear-gradient(90deg, transparent 5%, rgba(255,255,255,.9) 50%, transparent 95%);
  border-radius: 14px 14px 0 0;
}
.story-text {
  font-family: 'Lora', serif;
  font-size: var(--story-size);
  line-height: 2.6;
  color: var(--text);
  padding: 0 6px;
}
.story-text p {
  margin-bottom: 0;
  padding-bottom: 1.5em;
  text-indent: 2em;
  text-align: justify;
  hyphens: auto;
  -webkit-hyphens: auto;
}
/* First paragraph: no indent, optional drop cap */
.story-text p:first-child { text-indent: 0; }
.story-text p:first-child::first-letter {
  font-family: 'Lora', serif;
  font-size: 3.4em;
  font-weight: 500;
  line-height: 0.8;
  float: left;
  margin: 0.05em 0.1em 0 0;
  color: var(--accent);
}
.story-text p:last-child { padding-bottom: 0; }

/* ── TAB FADE + CARD TRANSITIONS ────────────────────────────────────── */
@keyframes tabFadeIn  { from { opacity:0; transform: translateY(5px); } to { opacity:1; transform: translateY(0); } }
@keyframes cardReveal { from { opacity:0; transform: translateY(8px) scale(0.98); } to { opacity:1; transform: translateY(0) scale(1); } }

/* ── FONT SIZE TOGGLE ────────────────────────────────────────────────── */
.font-controls {
  display: flex; align-items: center; gap: 4px;
  padding: 8px 0 6px;
  border-bottom: 1px solid var(--border);
}
.font-btn { width: 32px; height: 32px; border-radius: 8px; border: 1px solid var(--border); background: var(--surface); cursor: pointer; font-family: 'Inter', sans-serif; color: var(--muted); display: flex; align-items: center; justify-content: center; transition: all 0.12s; font-weight: 600; line-height: 1; touch-action: manipulation; }
.font-btn:hover, .font-btn:active { background: var(--surface2); color: var(--text); }
.font-btn.sz-sm { font-size: 11px; }
.font-btn.sz-lg { font-size: 15px; }

/* ── VOCAB CHIP ────────────────────────────────────────────────────────── */
.vocab-chip {
  display: inline;
  position: relative;
  background: none;
  border-radius: 0;
  padding: 0;
  cursor: pointer;
  transition: background 0.15s, border-radius 0.15s;
  color: inherit;
}
.vocab-chip:hover { background: var(--yellow); border-radius: 3px; }
.vocab-chip:active { background: var(--yellow-active); }
.vocab-chip .chip-text {
  border-bottom: 2px solid var(--yellow-border);
  transition: border-color 0.15s;
}
/* Chinese annotation sits inline to the right of the English word */
.vocab-chip .meaning {
  font-family: 'Inter', sans-serif;
  font-size: 10px;
  font-weight: 600;
  line-height: 1;
  color: var(--yellow-border);
  white-space: nowrap;
  pointer-events: none;
  margin-left: 3px;
  vertical-align: 0.15em;
}
.vocab-chip:hover .chip-text { border-bottom-color: var(--accent); }
/* SRS dot */
.vocab-chip::after {
  content: ''; display: inline-block;
  width: 3px; height: 3px; border-radius: 50%;
  margin-left: 2px; vertical-align: middle; opacity: 0;
}
.vocab-chip.srs-learning::after { background: #6899c4; opacity: 0.8; }
.vocab-chip.srs-known::after    { background: var(--green); opacity: 0.8; }
/* Known words: green underline + muted annotation = "already got this" feel */
.vocab-chip.srs-known .chip-text { border-bottom-color: var(--green); opacity: 0.7; }
.vocab-chip.srs-known .meaning { color: var(--green); opacity: 0.6; }
/* Learning words: blue underline to signal "in progress" */
.vocab-chip.srs-learning .chip-text { border-bottom-color: #6899c4; }
.vocab-chip.srs-learning .meaning { color: #6899c4; }
.vocab-chip.bookmarked .chip-text { border-bottom-color: var(--accent); }
.vocab-chip.bookmarked .meaning { color: var(--accent); }
.vocab-chip.bookmarked:hover { background: var(--accent-light); }

/* ── RECALL CARD (回想) ──────────────────────────────────────────────── */
.recall-wrap { max-width: 660px; }
.recall-hint-bar { font-size: 13px; color: var(--muted); margin-bottom: 18px; padding: 10px 14px; background: var(--surface2); border-radius: 8px; border-left: 2px solid var(--accent); line-height: 1.5; }
.recall-progress { font-size: 11px; color: var(--muted); margin-bottom: 14px; display: flex; align-items: center; gap: 8px; }
.recall-progress-bar { flex: 1; height: 3px; background: var(--border); border-radius: 99px; overflow: hidden; }
.recall-progress-fill { height: 100%; background: var(--accent); border-radius: 99px; transition: width 0.3s ease; }
.recall-grid { display: flex; flex-direction: column; gap: 10px; }
.recall-card {
  background: var(--surface); border: 1px solid var(--border); border-radius: 12px;
  padding: 16px 20px; cursor: pointer; transition: all 0.18s;
  display: flex; align-items: center; gap: 16px;
  box-shadow: 0 1px 4px rgba(0,0,0,.04);
  user-select: none;
}
.recall-card:hover { background: var(--surface2); border-color: var(--accent); transform: translateY(-1px); box-shadow: 0 3px 12px rgba(92,122,78,.1); }
.recall-card.revealed { cursor: default; }
.recall-card.revealed:hover { transform: none; }
.recall-card-meaning {
  font-size: 16px; font-weight: 500; color: var(--accent);
  background: var(--accent-light); padding: 6px 14px; border-radius: 8px;
  flex-shrink: 0; min-width: 80px; text-align: center;
  font-family: 'Inter', sans-serif;
}
.recall-card-english {
  font-family: 'Lora', serif; font-size: 17px; font-weight: 500; color: var(--text);
  flex: 1;
  transition: opacity 0.22s ease;
}
.recall-card-english.hidden-word {
  color: transparent; background: var(--border); border-radius: 4px;
  pointer-events: none; min-width: 80px; max-width: 180px;
  /* text hidden but takes up space */
}
.recall-card-tap { font-size: 11px; color: var(--muted); flex-shrink: 0; opacity: 0.6; font-style: italic; }

@keyframes pulse { 0%,100%{opacity:1} 50%{opacity:.55} }
.vocab-chip.playing, .vocab-blank.playing, .srs-play.playing { animation: pulse 0.5s 2; }
.vocab-row.playing td { background: var(--yellow) !important; }

.vtable { width: 100%; border-collapse: collapse; background: var(--surface); border-radius: 14px; overflow: hidden; border: 1px solid var(--border); font-size: 14px; box-shadow: 0 2px 12px rgba(0,0,0,.04), 0 1px 3px rgba(0,0,0,.03); }
.vtable thead tr { background: var(--surface2); border-bottom: 1px solid var(--border); }
.vtable th { padding: 9px 14px; text-align: left; font-size: 10px; text-transform: uppercase; letter-spacing: 0.8px; font-weight: 600; color: var(--muted); }
.vtable th.sortable { cursor: pointer; user-select: none; white-space: nowrap; }
.vtable th.sortable:hover { color: var(--text); }
.vtable th .sort-icon { display: inline-block; margin-left: 4px; opacity: 0.4; font-size: 9px; }
.vtable th.sort-asc .sort-icon, .vtable th.sort-desc .sort-icon { opacity: 1; color: var(--accent); }
.vtable tbody tr { border-bottom: 1px solid var(--border); transition: background 0.1s; cursor: pointer; }
.vtable tbody tr:last-child { border-bottom: none; }
.vtable tbody tr:hover { background: var(--surface2); }
.vtable td { padding: 9px 14px; vertical-align: middle; }
.td-word { font-family: 'Lora', serif; font-size: 14px; font-weight: 500; display: flex; align-items: center; gap: 7px; }
.play-btn { width: 24px; height: 24px; border-radius: 50%; background: var(--accent-light); border: none; cursor: pointer; display: flex; align-items: center; justify-content: center; font-size: 9px; transition: all 0.12s; flex-shrink: 0; }
.play-btn:hover { background: var(--accent); color: white; }

/* SRS */
.srs-wrap { max-width: 640px; }
.srs-filter { display: flex; gap: 6px; margin-bottom: 20px; align-items: center; flex-wrap: wrap; }
.srs-fl { font-size: 11px; color: var(--muted); font-weight: 600; text-transform: uppercase; letter-spacing: 0.8px; }
.srs-fb { padding: 9px 20px; border-radius: 8px; border: 1px solid var(--border); background: var(--surface); font-family: 'Inter', sans-serif; font-size: 13px; font-weight: 500; cursor: pointer; transition: all 0.12s; color: var(--muted); }
.srs-fb.active { background: var(--accent); color: white; border-color: var(--accent); }

/* 3D flip card */
.flip-scene { width: 100%; perspective: 900px; margin-bottom: 12px; }
.flip-card {
  width: 100%; position: relative; min-height: 210px;
  transform-style: preserve-3d;
  transition: transform 0.45s cubic-bezier(.4,0,.2,1);
}
.flip-card.flipped { transform: rotateX(180deg); }
.flip-front, .flip-back {
  backface-visibility: hidden; -webkit-backface-visibility: hidden;
  border-radius: 18px;
  background: var(--surface);
  border: 1px solid var(--border);
  box-shadow: 0 4px 20px rgba(42,96,73,.07), 0 1px 4px rgba(0,0,0,.05);
  padding: 36px 32px 30px; text-align: center; min-height: 210px;
  display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 16px;
}
.flip-back { position: absolute; top: 0; left: 0; right: 0; bottom: 0; transform: rotateX(180deg); }

.srs-card {
  background: var(--surface); border: 1px solid var(--border); border-radius: 20px;
  padding: 40px 32px 32px; text-align: center; margin-bottom: 12px; min-height: 220px;
  display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 16px;
  box-shadow: var(--shadow-card); animation: cardReveal 0.22s ease both;
  position: relative; overflow: hidden;
}
.srs-card::before {
  content: '';
  position: absolute; top: 0; left: 0; right: 0; height: 4px;
  background: linear-gradient(90deg, var(--accent), var(--accent-light) 60%, transparent);
}
.srs-ch { font-size: 10px; text-transform: uppercase; letter-spacing: 1.2px; color: var(--muted); }
.srs-word { font-family: 'Lora', serif; font-size: 42px; font-weight: 500; letter-spacing: -0.8px; }
.srs-ctx { font-family: 'Lora', serif; font-size: 15px; color: var(--muted); line-height: 1.75; max-width: 460px; font-style: italic; }
.srs-ctx .bw { color: var(--accent); font-weight: 500; font-style: normal; }
.srs-meaning { font-size: 20px; color: var(--accent); font-weight: 500; padding: 9px 22px; background: var(--accent-light); border-radius: 8px; }
.srs-play { width: 42px; height: 42px; border-radius: 50%; background: var(--accent); border: none; cursor: pointer; font-size: 15px; color: white; display: flex; align-items: center; justify-content: center; transition: all 0.15s; }
.srs-play:hover { background: var(--accent-hover); transform: scale(1.08); box-shadow: 0 3px 12px rgba(42,96,73,.3); }
.srs-prog { font-size: 11px; color: var(--muted); letter-spacing: 0.5px; }

.srs-reveal { width: 100%; padding: 15px; background: var(--accent); color: white; border: none; border-radius: 12px; font-family: 'Inter', sans-serif; font-size: 14px; font-weight: 500; cursor: pointer; margin-bottom: 10px; transition: opacity 0.15s, transform 0.1s; letter-spacing: 0.2px; }
.srs-reveal:hover { opacity: 0.88; transform: translateY(-1px); }
.srs-reveal:active { transform: translateY(0); }

/* Grade slide-off animations */
@keyframes gradeRight { to { opacity:0; transform: translateX(70px) scale(0.94) rotateZ(3deg); } }
@keyframes gradeLeft  { to { opacity:0; transform: translateX(-70px) scale(0.94) rotateZ(-3deg); } }
@keyframes gradeDown  { to { opacity:0; transform: translateY(30px) scale(0.95); } }
.card-exit-right { animation: gradeRight 0.2s ease forwards; }
.card-exit-left  { animation: gradeLeft  0.2s ease forwards; }
.card-exit-down  { animation: gradeDown  0.2s ease forwards; }

/* Grade tick flash */
@keyframes tickPop { 0%{opacity:0;transform:translate(-50%,-50%) scale(0.4)} 45%{opacity:1;transform:translate(-50%,-50%) scale(1.25)} 100%{opacity:0;transform:translate(-50%,-50%) scale(1.05)} }
.grade-tick { position: fixed; top: 42%; left: 50%; pointer-events: none; z-index: 999; font-size: 56px; animation: tickPop 0.5s ease forwards; }

/* Asymmetric grade buttons */
.srs-grades { display: grid; grid-template-columns: 1fr 1fr 1.3fr; gap: 8px; width: 100%; margin-top: 18px; }
.srs-g { padding: 13px 8px; border-radius: 12px; border: none; font-family: 'Inter', sans-serif; font-size: 13px; font-weight: 500; cursor: pointer; transition: all 0.15s; text-align: center; }
.srs-g:hover { transform: translateY(-2px); }
.srs-g:active { transform: translateY(0) scale(0.97); }
.srs-g .gl { display: block; font-size: 10px; opacity: 0.65; margin-top: 3px; }
.srs-g.again { background: var(--red-light); color: var(--red); }
.srs-g.again:hover { background: var(--red); color: white; box-shadow: 0 4px 12px rgba(220,38,38,.2); }
.srs-g.hard { background: var(--orange-light); color: var(--orange); }
.srs-g.hard:hover { background: var(--orange); color: white; box-shadow: 0 4px 12px rgba(234,88,12,.2); }
.srs-g.good { background: linear-gradient(135deg, var(--accent) 0%, var(--accent-hover) 100%); color: white; font-size: 14px; font-weight: 600; box-shadow: 0 2px 8px rgba(99,102,241,.25); }
.srs-g.good:hover { background: linear-gradient(135deg, var(--accent-hover) 0%, var(--accent) 100%); box-shadow: 0 4px 16px rgba(99,102,241,.35); }
.srs-g.good .gl { opacity: 0.75; }

/* Session summary */
.srs-summary { background: var(--surface); border: 1px solid var(--border); border-radius: 18px; padding: 44px 28px 32px; text-align: center; box-shadow: var(--shadow-card); animation: cardReveal 0.25s ease both; }
.srs-summary .sum-icon { font-size: 50px; display: block; margin-bottom: 14px; }
.srs-summary h3 { font-family: 'Lora', serif; font-size: 24px; font-weight: 500; margin-bottom: 6px; }
.srs-summary .sum-sub { font-size: 14px; color: var(--muted); margin-bottom: 24px; line-height: 1.65; }
.sum-stats { display: flex; gap: 10px; justify-content: center; margin-bottom: 24px; flex-wrap: wrap; }
.sum-stat { padding: 12px 18px; border-radius: 12px; background: var(--surface2); min-width: 76px; }
.sum-stat .sv { font-family: 'Lora', serif; font-size: 26px; font-weight: 600; line-height: 1; }
.sum-stat .sl { font-size: 10px; text-transform: uppercase; letter-spacing: 0.8px; color: var(--muted); margin-top: 4px; }
.sum-stat.s-good .sv { color: var(--accent); }
.sum-stat.s-hard .sv { color: var(--orange); }
.sum-stat.s-again .sv { color: var(--red); }

.srs-done { text-align: center; padding: 52px 28px; background: var(--surface); border: 1px solid var(--border); border-radius: 18px; box-shadow: var(--shadow-card); }
.srs-done .di { font-size: 52px; margin-bottom: 14px; }
.srs-done h3 { font-family: 'Lora', serif; font-size: 24px; margin-bottom: 8px; }
.srs-done p { font-size: 14px; color: var(--muted); margin-bottom: 22px; line-height: 1.6; }

.hint-bar { font-size: 13px; color: var(--muted); margin-bottom: 18px; padding: 10px 14px; background: var(--surface2); border-radius: 8px; border-left: 2px solid var(--accent); line-height: 1.5; }
.vtitle { font-size: 11px; text-transform: uppercase; letter-spacing: 1px; font-weight: 600; color: var(--muted); margin-bottom: 12px; }

.btn { padding: 9px 18px; border-radius: 9px; font-family: 'Inter', sans-serif; font-size: 13px; font-weight: 500; cursor: pointer; transition: all 0.15s; border: none; }
.btn-primary { background: var(--accent); color: white; }
.btn-primary:hover { background: var(--accent-hover); transform: translateY(-1px); box-shadow: 0 4px 12px rgba(42,96,73,.25); }
.btn-ghost { background: none; color: var(--muted); border: 1px solid var(--border); }
.btn-ghost:hover { background: var(--surface2); color: var(--text); }

.sidebar-overlay { display: none; position: fixed; inset: 0; background: rgba(0,0,0,.4); z-index: 90; }

/* ── TOUCH / MOBILE GLOBAL ───────────────────────────────────────────── */
* { -webkit-tap-highlight-color: transparent; }
button, [role="button"], .ch-item, .vocab-chip, .vocab-blank, .story-header, .tab {
  touch-action: manipulation; /* prevent 300ms delay */
}

@media (max-width: 900px) {
  /* iPad: slightly tighter sidebar */
  :root { --sw: 260px; }
}

@media (max-width: 700px) {
  .menu-btn { display: flex; }
  .hd-logo-mobile { display: block; }
  .layout { grid-template-columns: 1fr; }
  .sidebar { position: fixed; top: 44px; left: 0; bottom: 0; width: min(var(--sw), 85vw); z-index: 95; transform: translateX(-100%); }
  .sidebar.open { transform: translateX(0); }
  .sidebar-overlay.open { display: block; }
  .main { padding: 20px 18px calc(env(safe-area-inset-bottom, 0px) + 80px); }

  /* Bigger touch targets for chapter items */
  .ch-item { padding: 13px 16px 13px 20px; }
  .ch-item.active { padding-left: 17px; }
  .story-header { padding: 13px 14px 13px 12px; }

  /* SRS card */
  .srs-wrap { max-width: 100%; }
  .srs-card { padding: 28px 20px 24px; min-height: 200px; border-radius: 16px; }
  .srs-word { font-size: 32px; }
  .srs-reveal { padding: 17px; font-size: 15px; border-radius: 12px; }
  /* Grade buttons: bigger tap area, stack label inside nicely */
  .srs-grades { gap: 10px; }
  .srs-g { padding: 14px 8px; font-size: 13px; border-radius: 12px; }
  .srs-g.good { font-size: 14px; }
  .srs-g .gl { font-size: 10px; }

  /* Chapter header */
  .ch-title { font-size: 21px; }
  .chapter-header { padding: 20px 20px 18px; margin-bottom: 20px; }
  .ch-meta-row { gap: 8px; }

  /* Reading well: less padding on mobile */
  .story-box { padding: 22px 16px 26px; }
  /* Drop cap too large on mobile */
  .story-text p:first-child::first-letter { font-size: 2.8em; }

  /* Tabs: scrollable on very small screens */
  .tabs { overflow-x: auto; -webkit-overflow-scrolling: touch; gap: 0; }
  .tabs::-webkit-scrollbar { display: none; }
  .tab { font-size: 12px; padding: 10px 14px; flex-shrink: 0; }

  /* Story text — use CSS var so font-size buttons work on iOS */
  :root { --story-size: 15px; }
  .story-text { font-size: var(--story-size); line-height: 2.5; padding: 0 4px; }
  .story-box { padding: 18px 14px 24px; }

  /* Vocab table: hide due-date column (col 3) on small screens, keep bookmark/review */
  .vtable th:nth-child(3), .vtable td:nth-child(3) { display: none; }

  /* Bookmarks */
  .bookmark-card { padding: 14px; }
  .bk-play, .bk-remove { width: 36px; height: 36px; }
}

@media (max-width: 380px) {
  /* Small phones (iPhone SE etc) */
  .srs-word { font-size: 28px; }
  .tab { padding: 9px 11px; font-size: 11px; }
  .srs-grades { grid-template-columns: 1fr 1fr 1.2fr; gap: 7px; }
}

::-webkit-scrollbar { width: 4px; }
::-webkit-scrollbar-thumb { background: var(--border); border-radius: 99px; }

/* ── CHAPTER READ STATE ──────────────────────────────────────────────── */
.ch-item.read .ch-name { color: var(--muted); }
.ch-item.read .ch-num { color: var(--accent); opacity: 0.5; }
.ch-item { position: relative; }
.ch-item.read { background: linear-gradient(to right, var(--accent-light) 3px, transparent 3px); }

/* ── MOBILE WORD POPUP (same style as desktop, positioned near word) ── */
#mobileSheet { position: fixed; inset: 0; z-index: 600; pointer-events: none; }
#mobileSheet.show { pointer-events: all; }
#mobileSheetOverlay { position: absolute; inset: 0; background: transparent; }
#mobileSheetPanel {
  position: absolute;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 14px;
  box-shadow: 0 4px 12px rgba(44,40,32,.10), 0 12px 32px rgba(44,40,32,.15), 0 0 0 1px rgba(255,255,255,.4) inset;
  padding: 0;
  min-width: 200px;
  max-width: 240px;
  overflow: hidden;
  opacity: 0;
  transform: translateY(6px) scale(0.95);
  transform-origin: top center;
  transition: opacity 0.18s cubic-bezier(.16,1,.3,1), transform 0.18s cubic-bezier(.16,1,.3,1);
  pointer-events: none;
}
#mobileSheet.show #mobileSheetPanel {
  opacity: 1;
  transform: translateY(0) scale(1);
  pointer-events: all;
}
/* Arrow pointing at the tapped word */
#mobileSheetPanel::before {
  content: '';
  position: absolute;
  top: var(--ms-arrow-top, -5px);
  bottom: var(--ms-arrow-bottom, auto);
  left: var(--ms-arrow-left, 50%);
  transform: rotate(45deg);
  width: 9px; height: 9px;
  background: var(--surface);
  border-left: 1px solid var(--border);
  border-top: 1px solid var(--border);
  border-radius: 2px 0 0 0;
}
.ms-handle { display: none; }
.ms-word-row { display: flex; align-items: center; gap: 10px; padding: 12px 14px 8px; }
.ms-word { font-family: 'Lora', serif; font-size: 18px; font-weight: 500; flex: 1; line-height: 1.2; }
.ms-meaning { font-size: 12px; color: var(--muted); padding: 0 14px 10px; border-bottom: 1px solid var(--border); line-height: 1.4; }
.ms-actions { padding: 6px 8px 8px; display: flex; gap: 6px; }
.ms-action {
  flex: 1;
  display: flex; flex-direction: column; align-items: center; justify-content: center;
  gap: 4px;
  padding: 9px 6px; border-radius: 10px; border: 1px solid var(--border);
  font-family: 'Inter', sans-serif; font-size: 11px; font-weight: 500;
  cursor: pointer; transition: all 0.13s; color: var(--muted); background: none;
  text-align: center; line-height: 1.2;
}
.ms-action:hover, .ms-action:active { background: var(--surface2); color: var(--text); }
.ms-action.srs { }
.ms-action.srs:hover, .ms-action.srs:active { background: var(--accent-light); color: var(--accent); border-color: var(--accent-light); }
.ms-action-icon { display: flex; align-items: center; justify-content: center; line-height: 1; font-size: 15px; }
.ms-action.active { color: var(--accent); border-color: var(--accent-light); background: var(--accent-light); }

/* ── WORD ACTION POPUP ───────────────────────────────────────────────── */
#wordPopup {
  position: fixed; z-index: 500;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 16px;
  box-shadow:
    0 2px 8px rgba(44,40,32,.06),
    0 8px 24px rgba(44,40,32,.12),
    0 0 0 1px rgba(255,255,255,.5) inset;
  padding: 0;
  min-width: 220px;
  max-width: 260px;
  opacity: 0;
  transform: translateY(6px) scale(0.96);
  transform-origin: top center;
  transition: opacity 0.18s cubic-bezier(.16,1,.3,1), transform 0.18s cubic-bezier(.16,1,.3,1);
  pointer-events: none;
  overflow: hidden;
}
#wordPopup.show {
  opacity: 1;
  transform: translateY(0) scale(1);
  pointer-events: all;
}
/* Tiny caret/arrow pointing at the word */
#wordPopup::before {
  content: '';
  position: absolute;
  top: var(--arrow-top, -5px);
  bottom: var(--arrow-bottom, auto);
  left: var(--arrow-left, 50%);
  transform: rotate(45deg);
  width: 9px; height: 9px;
  background: var(--surface);
  border-left: 1px solid var(--border);
  border-top: 1px solid var(--border);
  border-radius: 2px 0 0 0;
}
.wp-header {
  padding: 14px 16px 10px;
  display: flex; align-items: flex-start; gap: 10px;
}
.wp-word-col { flex: 1; min-width: 0; }
.wp-word {
  font-family: 'Inter', sans-serif; font-size: 15px; font-weight: 600;
  color: var(--text); line-height: 1.2; margin-bottom: 3px;
  letter-spacing: 0.3px;
}
.wp-meaning {
  font-size: 12px; color: var(--muted); line-height: 1.4;
  font-family: 'Inter', sans-serif; letter-spacing: 0.2px;
}
.wp-play-btn {
  width: 32px; height: 32px; border-radius: 50%;
  background: var(--accent-light); border: 1px solid transparent;
  cursor: pointer; font-size: 12px;
  display: flex; align-items: center; justify-content: center;
  transition: all 0.14s; flex-shrink: 0; color: var(--accent);
  margin-top: 1px;
}
.wp-play-btn:hover {
  background: var(--accent); color: white;
  transform: scale(1.05);
  box-shadow: 0 3px 10px rgba(92,122,78,.3);
}
.wp-divider {
  height: 1px; background: var(--border); margin: 0 12px;
  opacity: 0.6;
}
.wp-actions {
  padding: 8px;
  display: flex; gap: 6px;
}
.wp-action {
  flex: 1;
  display: flex; flex-direction: column; align-items: center; justify-content: center;
  gap: 4px;
  padding: 9px 6px; border-radius: 10px; border: 1px solid var(--border);
  font-family: 'Inter', sans-serif; font-size: 11px; font-weight: 500;
  cursor: pointer; transition: all 0.13s; color: var(--muted); background: none;
  text-align: center; line-height: 1.2;
}
.wp-action:hover {
  background: var(--surface2); color: var(--text);
  border-color: var(--border);
  transform: translateY(-1px);
}
.wp-action.active { color: var(--accent); border-color: var(--accent-light); background: var(--accent-light); }
.wp-action.srs-action { }
.wp-action.srs-action:hover { background: var(--accent-light); color: var(--accent); border-color: var(--accent-light); }
.wp-action-icon { display: flex; align-items: center; justify-content: center; line-height: 1; }

/* ── BOOKMARK TAB ────────────────────────────────────────────────────── */
.bookmarks-wrap { max-width: 700px; }
.bookmarks-header { display: flex; align-items: center; justify-content: space-between; margin-bottom: 16px; }
.bookmarks-title { font-family: 'Lora', serif; font-size: 18px; font-weight: 500; }
.bookmarks-clear { font-size: 11px; color: var(--muted); background: none; border: none; cursor: pointer; padding: 4px 8px; border-radius: 6px; }
.bookmarks-clear:hover { background: var(--surface2); color: var(--text); }

.bookmarks-empty { text-align: center; padding: 48px 24px; color: var(--muted); }
.bookmarks-empty .be-icon { font-size: 36px; opacity: 0.3; margin-bottom: 10px; }
.bookmarks-empty p { font-size: 13px; line-height: 1.7; }

.bookmark-list { display: flex; flex-direction: column; gap: 8px; }
.bookmark-card {
  background: var(--surface); border: 1px solid var(--border); border-radius: 10px;
  padding: 12px 14px; display: flex; align-items: flex-start; gap: 12px;
  transition: background 0.1s;
}
.bookmark-card:hover { background: var(--surface2); }
.bk-word { font-family: 'Lora', serif; font-size: 16px; font-weight: 500; flex: 1; }
.bk-meaning { font-size: 12px; color: var(--muted); margin-top: 2px; }
.bk-chapter { font-size: 10px; color: var(--accent); margin-top: 4px; text-transform: uppercase; letter-spacing: 0.5px; }
.bk-actions { display: flex; gap: 6px; align-items: center; }
.bk-play { width: 28px; height: 28px; border-radius: 50%; background: var(--accent-light); border: none; cursor: pointer; font-size: 10px; transition: all 0.12s; display: flex; align-items: center; justify-content: center; }
.bk-play:hover { background: var(--accent); color: white; }
.bk-srs { padding: 4px 9px; border-radius: 6px; font-size: 11px; font-weight: 500; background: var(--accent-light); color: var(--accent); border: none; cursor: pointer; white-space: nowrap; transition: all 0.12s; font-family: 'Inter', sans-serif; }
.bk-srs:hover { background: var(--accent); color: white; }
.bk-remove { width: 24px; height: 24px; border-radius: 50%; background: none; border: none; cursor: pointer; font-size: 14px; color: var(--muted); display: flex; align-items: center; justify-content: center; transition: all 0.12s; }
.bk-remove:hover { background: var(--red-light); color: var(--red); }

/* vocab table bookmark btn */
.bk-star { width: 26px; height: 26px; border-radius: 6px; background: none; border: none; cursor: pointer; font-size: 13px; color: var(--muted); display: flex; align-items: center; justify-content: center; transition: all 0.12px; }
.bk-star:hover { background: var(--yellow); }
.bk-star.active { color: #d97706; }

/* sidebar bookmark nav */
.sidebar-nav { display: flex; gap: 0; border-bottom: 1px solid var(--border); }
.sidebar-nav-btn { flex: 1; padding: 8px 4px; font-size: 10px; font-weight: 600; text-transform: uppercase; letter-spacing: 0.8px; color: var(--muted); border: none; background: none; cursor: pointer; transition: all 0.12s; border-bottom: 2px solid transparent; font-family: 'Inter', sans-serif; }
.sidebar-nav-btn.active { color: var(--accent); border-bottom-color: var(--accent); background: var(--accent-light); }
.sidebar-nav-btn:hover:not(.active) { background: var(--surface2); color: var(--text); }

/* vocab srs button */
.vocab-srs-btn { padding: 4px 8px; border-radius: 6px; font-size: 11px; font-weight: 500; background: var(--surface2); color: var(--muted); border: 1px solid var(--border); cursor: pointer; white-space: nowrap; transition: all 0.12s; font-family: 'Inter', sans-serif; }
.vocab-srs-btn:hover { background: var(--accent-light); color: var(--accent); border-color: var(--accent); }
.vocab-srs-btn.srs-in { background: var(--accent-light); color: var(--accent); border-color: var(--accent); }

/* chapter navigation */
.ch-nav { display: flex; justify-content: space-between; align-items: center; margin-top: 28px; padding-top: 20px; border-top: 1px solid var(--border); gap: 12px; }
.ch-nav-btn { display: flex; align-items: center; gap: 8px; padding: 10px 14px; border-radius: 10px; border: 1px solid var(--border); background: var(--surface); cursor: pointer; font-family: 'Inter', sans-serif; font-size: 12px; color: var(--muted); transition: all 0.14s; text-align: left; max-width: 48%; }
.ch-nav-btn:hover { background: var(--accent-light); border-color: var(--accent); color: var(--accent); }
.ch-nav-btn.next { text-align: right; flex-direction: row-reverse; margin-left: auto; }
.ch-nav-btn .nav-arrow { font-size: 16px; flex-shrink: 0; }
.ch-nav-btn .nav-info { min-width: 0; }
.ch-nav-label { font-size: 10px; text-transform: uppercase; letter-spacing: 0.8px; font-weight: 600; margin-bottom: 2px; }
.ch-nav-title { font-size: 12px; font-weight: 500; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; max-width: 160px; }
@media (max-width: 700px) {
  .ch-nav-title { max-width: 100px; }
}
@keyframes toastIn { from { opacity:0; transform: translateY(8px); } to { opacity:1; transform: translateY(0); } }
@keyframes toastOut { from { opacity:1; } to { opacity:0; transform: translateY(-4px); } }
.progress-toast {
  position: fixed; bottom: 20px; left: 50%; transform: translateX(-50%);
  background: var(--text); color: white;
  padding: 8px 14px; border-radius: 20px;
  font-size: 12px; font-weight: 500;
  z-index: 999; pointer-events: none;
  animation: toastIn 0.2s ease forwards;
  white-space: nowrap;
}
.progress-toast.out { animation: toastOut 0.2s ease forwards; }

/* ── ONBOARDING TOOLTIPS ─────────────────────────────────────────────── */
.onboard-overlay { position: fixed; inset: 0; z-index: 800; pointer-events: none; }
.onboard-backdrop { position: absolute; inset: 0; background: rgba(0,0,0,.5); pointer-events: all; }
.onboard-tip {
  position: absolute; background: var(--text); color: #f5f4f0;
  border-radius: 12px; padding: 16px 18px; max-width: 280px;
  box-shadow: 0 8px 32px rgba(0,0,0,.3);
  pointer-events: all; z-index: 801;
  animation: tipIn 0.25s cubic-bezier(.16,1,.3,1) both;
}
@keyframes tipIn { from { opacity:0; transform: scale(0.92) translateY(6px); } to { opacity:1; transform: scale(1) translateY(0); } }
.onboard-tip::before {
  content: ''; position: absolute; width: 10px; height: 10px;
  background: var(--text); transform: rotate(45deg);
}
.onboard-tip.arrow-top::before { top: -5px; left: 24px; }
.onboard-tip.arrow-bottom::before { bottom: -5px; left: 24px; }
.onboard-tip.arrow-left::before { left: -5px; top: 20px; }
.onboard-step { font-size: 10px; color: #6b7280; text-transform: uppercase; letter-spacing: 1px; margin-bottom: 6px; }
.onboard-title { font-family: 'Lora', serif; font-size: 16px; font-weight: 500; margin-bottom: 6px; }
.onboard-body { font-size: 13px; color: #9ca3af; line-height: 1.6; margin-bottom: 14px; }
.onboard-actions { display: flex; gap: 8px; align-items: center; }
.onboard-next { padding: 7px 16px; background: var(--accent); color: white; border: none; border-radius: 7px; font-size: 12px; font-weight: 600; cursor: pointer; font-family: 'Inter', sans-serif; }
.onboard-skip { font-size: 11px; color: #6b7280; background: none; border: none; cursor: pointer; font-family: 'Inter', sans-serif; padding: 4px; }
.onboard-dots { display: flex; gap: 5px; margin-left: auto; }
.onboard-dot { width: 5px; height: 5px; border-radius: 50%; background: #374151; }
.onboard-dot.active { background: var(--accent); }

/* ── GLOBAL VOCAB VIEW ───────────────────────────────────────────────── */
.gvocab-wrap { max-width: 700px; }
.gvocab-header { display: flex; align-items: center; justify-content: space-between; margin-bottom: 20px; gap: 12px; flex-wrap: wrap; }
.gvocab-title { font-family: 'Lora', serif; font-size: 22px; font-weight: 500; }
.gvocab-filters { display: flex; gap: 6px; flex-wrap: wrap; }
.gvf { padding: 5px 12px; border-radius: 6px; border: 1px solid var(--border); background: var(--surface); font-family: 'Inter', sans-serif; font-size: 11px; cursor: pointer; transition: all 0.12s; color: var(--muted); }
.gvf.active { background: var(--accent); color: white; border-color: var(--accent); }
.gvocab-search { width: 100%; padding: 9px 14px; border-radius: 9px; border: 1px solid var(--border); background: var(--surface); font-family: 'Inter', sans-serif; font-size: 14px; color: var(--text); outline: none; margin-bottom: 16px; transition: border-color 0.15s; }
.gvocab-search:focus { border-color: var(--accent); box-shadow: 0 0 0 3px var(--accent-light); }
.gvocab-empty { text-align: center; padding: 48px 24px; color: var(--muted); font-size: 14px; }

/* ── GATE SPLIT SCREEN ───────────────────────────────────────────────── */
#gate { flex-direction: row; }
.gate-left {
  flex: 0 0 380px; display: flex; align-items: center; justify-content: center;
  padding: 48px 40px; border-right: 1px solid #1e1c38;
}
.gate-right {
  flex: 1; display: flex; align-items: center; justify-content: center;
  padding: 40px; overflow: hidden; position: relative;
}
.gate-preview {
  max-width: 480px; width: 100%;
  background: #16152a; border: 1px solid #2e2c50;
  border-radius: 16px; padding: 28px 32px;
  box-shadow: 0 20px 60px rgba(0,0,0,.5), 0 0 0 1px rgba(129,140,248,.08) inset;
}
.gate-preview-label {
  font-size: 10px; letter-spacing: 1.5px; text-transform: uppercase;
  color: #818cf8; font-weight: 600; margin-bottom: 12px;
}
.gate-preview-title {
  font-family: 'Lora', serif; font-size: 18px; color: #e8e5dc;
  margin-bottom: 18px; line-height: 1.3; font-weight: 500;
}
.gate-preview-text {
  font-family: 'Lora', serif; font-size: 14px; line-height: 2.1;
  color: #8a8880; text-align: justify; hyphens: auto;
}
/* Vocab highlight in preview */
@keyframes chipGlow { 0%,100% { border-bottom-color: #818cf8; color: #e8e8ff; } 50% { border-bottom-color: #a5b4fc; color: #fff; } }
.gpv-word {
  color: #e8e8ff; border-bottom: 1.5px solid #818cf8;
  cursor: default; animation: chipGlow 2.4s ease-in-out infinite;
}
.gpv-word:nth-child(2) { animation-delay: 0.5s; }
.gpv-word:nth-child(3) { animation-delay: 1s; }
.gpv-word:nth-child(4) { animation-delay: 1.5s; }
.gpv-word:nth-child(5) { animation-delay: 2s; }
.gate-preview-tagline {
  margin-top: 18px; padding-top: 16px; border-top: 1px solid #2a2a26;
  font-size: 12px; color: #6a6a70; line-height: 1.6;
  display: flex; gap: 16px; flex-wrap: wrap;
}
.gate-preview-tagline span { display: flex; align-items: center; gap: 5px; color: #8888b0; }
@media (max-width: 800px) {
  #gate { flex-direction: column; }
  .gate-left { flex: none; border-right: none; border-bottom: 1px solid #1e1e1b; padding: 32px 28px; width: 100%; }
  .gate-right { display: none; }
}

/* ── ACCESS GATE ─────────────────────────────────────────────────────── */
#gate {
  position: fixed; inset: 0; z-index: 9999;
  background: #0c0b18;
  display: flex; align-items: center; justify-content: center;
  font-family: 'Inter', sans-serif;
}
#gate.hidden { display: none; }

.gate-card {
  width: 100%; max-width: 340px; padding: 0 28px;
  display: flex; flex-direction: column; align-items: center; gap: 0;
  animation: gateIn 0.55s cubic-bezier(.16,1,.3,1) both;
}
@keyframes gateIn {
  from { opacity: 0; transform: translateY(18px); }
  to   { opacity: 1; transform: translateY(0); }
}

.gate-logo {
  display: flex; flex-direction: column; align-items: center; gap: 8px;
  margin-bottom: 40px;
}
.gate-logo-icon { display: block; }
.gate-logo-text {
  font-family: 'Inter', sans-serif;
  font-size: 28px; font-weight: 700;
  color: #f0f0ff;
  letter-spacing: 4px;
  text-transform: uppercase;
  line-height: 1;
}
.gate-logo-sub {
  font-family: 'Inter', sans-serif;
  font-size: 10px; font-weight: 500; letter-spacing: 5px;
  color: #818cf8; text-transform: uppercase;
  margin-top: 4px;
}
.gate-logo-dot { display: none; }

.gate-label {
  width: 100%;
  font-size: 10px; font-weight: 600; letter-spacing: 1.4px;
  text-transform: uppercase; color: #484843;
  margin-bottom: 10px;
}

.gate-input-wrap {
  width: 100%; position: relative; margin-bottom: 10px;
}
.gate-input {
  width: 100%;
  background: #1a1930; border: 1px solid #2e2c50;
  border-radius: 10px; padding: 14px 16px;
  font-family: 'Inter', sans-serif;
  font-size: 18px; font-weight: 500; letter-spacing: 4px;
  color: #f0f0ff; text-align: center; text-transform: uppercase;
  outline: none; transition: border-color 0.15s, box-shadow 0.15s;
  caret-color: #818cf8;
}
.gate-input::placeholder { letter-spacing: 2px; font-size: 13px; color: #3a3860; font-weight: 400; }
.gate-input:focus { border-color: #6366f1; box-shadow: 0 0 0 3px #6366f122; }
.gate-input.error { border-color: #dc2626; box-shadow: 0 0 0 3px #dc262622; animation: shake 0.35s ease; }
.gate-input.success { border-color: #6366f1; box-shadow: 0 0 0 3px #6366f133; }
@keyframes shake {
  0%,100% { transform: translateX(0); }
  20%,60% { transform: translateX(-6px); }
  40%,80% { transform: translateX(6px); }
}

.gate-btn {
  width: 100%; padding: 14px;
  background: linear-gradient(135deg, #6366f1, #8b5cf6);
  border: none; border-radius: 10px;
  font-family: 'Inter', sans-serif; font-size: 13px; font-weight: 600;
  letter-spacing: 0.5px; color: white; cursor: pointer;
  transition: opacity 0.15s, transform 0.1s, box-shadow 0.15s;
  margin-bottom: 0;
  box-shadow: 0 4px 20px rgba(99,102,241,.35);
}
.gate-btn:hover { opacity: 0.9; box-shadow: 0 6px 24px rgba(99,102,241,.45); }
.gate-btn:active { transform: scale(0.98); }
.gate-btn:disabled { opacity: 0.35; cursor: not-allowed; }

.gate-error {
  font-size: 12px; color: #ef4444;
  min-height: 18px; text-align: center;
  margin-bottom: 8px; transition: opacity 0.2s;
}

.gate-footer {
  font-size: 11px; color: #38382f; text-align: center; margin-top: 8px;
  line-height: 1.7;
}
.gate-tagline {
  font-size: 13px; color: #5a5878; text-align: center;
  margin-bottom: 32px; margin-top: -28px; line-height: 1.5;
  letter-spacing: 0.2px;
}
.gate-contact { color: #818cf8; text-decoration: none; transition: opacity 0.15s; }
.gate-contact:hover { opacity: 0.75; text-decoration: underline; }

/* ── DATA MANAGEMENT BUTTONS ─────────────────────────────────────────── */
.data-mgmt { display: flex; gap: 6px; padding: 0 12px 8px; }
.data-btn { flex: 1; padding: 6px 8px; font-size: 11px; font-family: 'Inter', sans-serif; background: var(--surface2); border: 1px solid var(--border); border-radius: 6px; color: var(--muted); cursor: pointer; transition: all 0.12s; }
.data-btn:hover { color: var(--text); border-color: var(--accent); }

/* ── KEYBOARD HINT ───────────────────────────────────────────────────── */
.srs-kbd-hint { text-align: center; font-size: 11px; color: var(--muted); margin-top: 10px; font-family: 'Inter', sans-serif; }
.srs-kbd-hint kbd { background: var(--surface2); border: 1px solid var(--border); border-radius: 4px; padding: 1px 5px; font-size: 10px; }

/* ── STORY BLURB IN SIDEBAR ──────────────────────────────────────────── */
.story-blurb {
  font-size: 11px; color: var(--muted); line-height: 1.55;
  margin-top: 5px; font-style: italic; opacity: 0.85;
  white-space: normal; overflow: visible;
}
.story-group.open .story-blurb { color: var(--accent); opacity: 0.7; }

/* ── CHAPTER ROADMAP ─────────────────────────────────────────────────── */
.ch-roadmap {
  display: flex; align-items: center; gap: 4px;
  margin-top: 14px; flex-wrap: nowrap; overflow: hidden;
}
.crm-dot {
  width: 8px; height: 8px; border-radius: 50%;
  background: var(--border); border: 1px solid var(--border);
  flex-shrink: 0; cursor: pointer; transition: all 0.2s;
}
.crm-dot:hover { transform: scale(1.3); }
.crm-dot.read { background: var(--green); border-color: var(--green); opacity: 0.75; }
.crm-dot.active {
  width: 10px; height: 10px;
  background: var(--accent); border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-light);
  cursor: default;
}
.crm-label {
  font-size: 10px; color: var(--muted); margin-left: 8px;
  flex-shrink: 0; font-variant-numeric: tabular-nums;
  letter-spacing: 0.3px;
}

/* ── POPUP IPA LINE ──────────────────────────────────────────────────── */
.wp-ipa {
  font-size: 11px; color: var(--muted); font-family: 'Inter', sans-serif;
  letter-spacing: 0.3px; margin-bottom: 2px; min-height: 0;
  font-style: italic; opacity: 0.75;
}
.ms-ipa {
  font-size: 11px; color: var(--muted); padding: 0 14px 6px;
  font-family: 'Inter', sans-serif; letter-spacing: 0.3px;
  font-style: italic; opacity: 0.75;
}
/* Always show Chinese meaning as accent color */
.wp-meaning { color: var(--accent) !important; font-weight: 500 !important; font-size: 13px !important; }
.ms-meaning { color: var(--accent) !important; font-weight: 600 !important; font-size: 13px !important; padding-bottom: 4px !important; }

/* ── WORD MILESTONE MODAL ────────────────────────────────────────────── */
@keyframes milestoneIn { from { opacity:0; transform: translate(-50%,-50%) scale(0.75); } to { opacity:1; transform: translate(-50%,-50%) scale(1); } }
.milestone-backdrop {
  position: fixed; inset: 0; background: rgba(0,0,0,.45); z-index: 1200;
}
.milestone-modal {
  position: fixed; top: 50%; left: 50%;
  transform: translate(-50%,-50%);
  z-index: 1201; background: var(--surface); border: 1px solid var(--border);
  border-radius: 20px; padding: 36px 32px; text-align: center;
  box-shadow: 0 24px 64px rgba(0,0,0,.28); max-width: 320px; width: 88%;
  animation: milestoneIn 0.4s cubic-bezier(.16,1,.3,1) both;
}
.milestone-icon { font-size: 52px; display: block; margin-bottom: 10px; }
.milestone-count {
  font-family: 'Lora', serif; font-size: 48px; font-weight: 600;
  color: var(--accent); line-height: 1; margin-bottom: 4px;
}
.milestone-title { font-family: 'Lora', serif; font-size: 20px; font-weight: 500; margin-bottom: 8px; }
.milestone-body { font-size: 13px; color: var(--muted); line-height: 1.65; margin-bottom: 22px; }
.milestone-dismiss {
  padding: 11px 32px; background: var(--accent); color: white;
  border: none; border-radius: 10px; font-family: 'Inter', sans-serif;
  font-size: 13px; font-weight: 600; cursor: pointer; transition: all 0.15s;
}
.milestone-dismiss:hover { background: var(--accent-hover); transform: translateY(-1px); }

/* ── HEADER SEARCH BUTTON ───────────────────────────────────────────── */
.header-search-btn {
  width: 32px; height: 32px; border-radius: 8px; border: 1px solid var(--border);
  background: none; cursor: pointer; color: var(--muted);
  display: flex; align-items: center; justify-content: center;
  transition: all 0.14s;
}
.header-search-btn:hover { background: var(--surface2); color: var(--text); border-color: var(--accent); }

/* ── SEARCH MODAL ────────────────────────────────────────────────────── */
#searchModal {
  position: fixed; inset: 0; z-index: 2000; display: none;
  align-items: flex-start; justify-content: center; padding-top: 80px;
}
#searchModal.open { display: flex; }
.search-backdrop { position: absolute; inset: 0; background: rgba(0,0,0,.45); }
.search-panel {
  position: relative; width: 100%; max-width: 560px; margin: 0 16px;
  background: var(--surface); border: 1px solid var(--border);
  border-radius: 14px; overflow: hidden;
  box-shadow: 0 20px 60px rgba(0,0,0,.3);
  animation: searchIn 0.18s cubic-bezier(.16,1,.3,1) both;
  max-height: calc(100vh - 120px); display: flex; flex-direction: column;
}
@keyframes searchIn { from { opacity:0; transform: translateY(-12px) scale(0.97); } to { opacity:1; transform: none; } }
.search-input-row {
  display: flex; align-items: center; gap: 10px;
  padding: 14px 16px; border-bottom: 1px solid var(--border);
  flex-shrink: 0;
}
.search-input {
  flex: 1; border: none; background: none; font-family: 'Inter', sans-serif;
  font-size: 16px; color: var(--text); outline: none;
}
.search-input::placeholder { color: var(--muted); }
.search-close {
  width: 26px; height: 26px; border-radius: 50%; border: none; background: var(--surface2);
  color: var(--muted); cursor: pointer; font-size: 12px; transition: all 0.12s;
  display: flex; align-items: center; justify-content: center; flex-shrink: 0;
}
.search-close:hover { background: var(--border); color: var(--text); }
.search-results { overflow-y: auto; max-height: 420px; -webkit-overflow-scrolling: touch; }
.search-empty { padding: 32px; text-align: center; color: var(--muted); font-size: 14px; }
.search-result-item {
  display: flex; align-items: center; gap: 12px;
  padding: 11px 16px; cursor: pointer; transition: background 0.1s;
  border-bottom: 1px solid var(--border);
}
.search-result-item:last-child { border-bottom: none; }
.search-result-item:hover { background: var(--surface2); }
.sri-word { font-family: 'Lora', serif; font-size: 15px; font-weight: 500; color: var(--text); flex-shrink: 0; min-width: 90px; }
.sri-meaning { font-size: 13px; color: var(--accent); font-weight: 500; flex: 1; }
.sri-chapter { font-size: 11px; color: var(--muted); white-space: nowrap; overflow: hidden; text-overflow: ellipsis; max-width: 140px; }

/* ── HOME SCREEN / WORD OF DAY ───────────────────────────────────────── */
.home-wrap {
  display: flex; flex-direction: column; align-items: center;
  justify-content: center; min-height: calc(100vh - 44px - 60px);
  padding: 32px 24px; text-align: center; gap: 20px;
}
.home-today-label {
  font-size: 10px; font-weight: 700; letter-spacing: 2px;
  text-transform: uppercase; color: var(--accent); opacity: 0.7;
}
.home-card {
  background: var(--surface); border: 1px solid var(--border);
  border-radius: 20px; padding: 32px 36px 28px;
  box-shadow: var(--shadow-card); max-width: 380px; width: 100%;
  animation: cardReveal 0.3s ease both;
  position: relative; overflow: hidden;
}
.home-card::before {
  content: ''; position: absolute; top: 0; left: 0; right: 0; height: 3px;
  background: linear-gradient(90deg, var(--accent), var(--accent-light) 60%, transparent);
}
.home-word-row { display: flex; align-items: flex-start; justify-content: space-between; margin-bottom: 6px; }
.home-word { font-family: 'Lora', serif; font-size: 36px; font-weight: 500; color: var(--text); text-align: left; line-height: 1.2; }
.home-syllable { font-size: 12px; color: var(--muted); margin-top: 4px; letter-spacing: 0.5px; font-family: 'Inter', sans-serif; }
.home-play-btn {
  width: 40px; height: 40px; border-radius: 50%; background: var(--accent);
  border: none; cursor: pointer; color: white; display: flex; align-items: center;
  justify-content: center; transition: all 0.15s; flex-shrink: 0; margin-top: 4px;
}
.home-play-btn:hover { background: var(--accent-hover); transform: scale(1.08); }
.home-meaning {
  font-size: 22px; color: var(--accent); font-weight: 600;
  margin: 12px 0 8px; font-family: 'Inter', sans-serif;
}
.home-source { font-size: 11px; color: var(--muted); margin-bottom: 20px; }
.home-srs-btn {
  width: 100%; padding: 11px; background: var(--accent-light); color: var(--accent);
  border: 1px solid var(--accent-light); border-radius: 10px;
  font-family: 'Inter', sans-serif; font-size: 13px; font-weight: 600;
  cursor: pointer; transition: all 0.15s;
}
.home-srs-btn:hover { background: var(--accent); color: white; }
.home-srs-btn:disabled { opacity: 0.5; cursor: default; }
.home-hint { font-size: 13px; color: var(--muted); opacity: 0.6; }

/* ── CHAPTER COMPLETION BANNER ───────────────────────────────────────── */
@keyframes bannerSlideUp { from { opacity:0; transform: translateY(16px); } to { opacity:1; transform: none; } }
.ch-complete-banner {
  margin-top: 28px; padding: 28px 28px 24px; text-align: center;
  background: var(--surface); border: 1px solid var(--border);
  border-radius: 16px; box-shadow: var(--shadow-md);
  animation: bannerSlideUp 0.35s cubic-bezier(.16,1,.3,1) both;
  position: relative; overflow: hidden;
}
.ch-complete-banner::before {
  content: ''; position: absolute; top: 0; left: 0; right: 0; height: 3px;
  background: linear-gradient(90deg, var(--green), transparent);
}
.ccb-check { font-size: 28px; color: var(--green); margin-bottom: 6px; }
.ccb-text {
  font-family: 'Lora', serif; font-size: 18px; font-weight: 500;
  color: var(--text); margin-bottom: 16px;
}
.ccb-next {
  width: 100%; padding: 13px 20px; background: var(--accent); color: white;
  border: none; border-radius: 10px; font-family: 'Inter', sans-serif;
  font-size: 14px; font-weight: 600; cursor: pointer; transition: all 0.15s;
  letter-spacing: 0.2px;
}
.ccb-next:hover { background: var(--accent-hover); transform: translateY(-1px); box-shadow: 0 4px 16px rgba(99,102,241,.3); }
.ccb-end { font-size: 14px; color: var(--muted); font-style: italic; }

/* ── RECENT CHAPTERS SIDEBAR ─────────────────────────────────────────── */
.recent-section { padding: 10px 10px 8px; border-bottom: 1px solid var(--border); }
.recent-label {
  display: flex; align-items: center; gap: 5px;
  font-size: 9px; font-weight: 700; text-transform: uppercase;
  letter-spacing: 1.2px; color: var(--muted); padding: 0 4px 7px;
}
.recent-item {
  display: flex; flex-direction: column; gap: 2px;
  padding: 7px 10px 7px 12px; cursor: pointer;
  border-radius: 8px; margin-bottom: 3px;
  background: var(--surface2);
  border-left: 3px solid var(--accent);
  transition: background 0.12s, border-color 0.12s;
}
.recent-item:hover { background: var(--accent-light); }
.recent-item.active { background: var(--accent-light); border-left-color: var(--accent); }
.recent-item-story { font-size: 9px; color: var(--accent); font-weight: 600; text-transform: uppercase; letter-spacing: 0.5px; opacity: 0.8; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.recent-item-title { font-size: 12px; color: var(--text); font-weight: 500; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; line-height: 1.3; }

/* ── POPUP DEFINITIONS ───────────────────────────────────────────────── */
.wp-defs {
  padding: 0 16px 8px; display: flex; flex-direction: column; gap: 4px;
}
.wp-def-item { font-size: 11px; color: var(--muted); line-height: 1.5; }
.wp-pos { font-style: italic; color: var(--accent); opacity: 0.7; margin-right: 4px; font-size: 10px; }
.ms-defs { padding: 0 14px 6px; display: flex; flex-direction: column; gap: 4px; }
.ms-def-item { font-size: 11px; color: var(--muted); line-height: 1.5; }

/* ── PROGRESS REPORT MODAL ───────────────────────────────────────────── */
#progressModal {
  position: fixed; inset: 0; z-index: 2000; display: none;
  align-items: center; justify-content: center;
}
#progressModal.open { display: flex; }
.progress-modal-backdrop { position: absolute; inset: 0; background: rgba(0,0,0,.55); }
.progress-modal-inner {
  position: relative; background: var(--surface); border: 1px solid var(--border);
  border-radius: 18px; padding: 20px 20px 24px; max-width: 580px; width: 92%;
  box-shadow: 0 24px 64px rgba(0,0,0,.35);
  animation: milestoneIn 0.3s cubic-bezier(.16,1,.3,1) both;
  max-height: 90vh; overflow-y: auto;
}
.pm-header { display: flex; align-items: center; justify-content: space-between; margin-bottom: 16px; }
.pm-title { font-family: 'Lora', serif; font-size: 18px; font-weight: 500; }
.pm-close-btn { width: 28px; height: 28px; border-radius: 50%; border: 1px solid var(--border); background: none; cursor: pointer; color: var(--muted); font-size: 13px; display: flex; align-items: center; justify-content: center; transition: all 0.12s; }
.pm-close-btn:hover { background: var(--surface2); color: var(--text); }
.pm-hint { font-size: 12px; color: var(--muted); text-align: center; margin: 12px 0 14px; line-height: 1.6; }
.pm-download {
  display: block; width: 100%; padding: 12px; background: var(--accent); color: white;
  border: none; border-radius: 10px; font-family: 'Inter', sans-serif;
  font-size: 13px; font-weight: 600; cursor: pointer; transition: all 0.15s;
}
.pm-download:hover { background: var(--accent-hover); }

/* ── READING EXPERIENCE IMPROVEMENTS ────────────────────────────────── */
/* Warm parchment feel on light theme */
[data-theme="light"] .story-box {
  background: linear-gradient(to bottom, #ffffff 0%, #fdfcf7 100%);
}
/* Decorative opening ornament before story text */
.story-text::before {
  content: '';
  display: block;
  height: 1px;
  background: linear-gradient(90deg, transparent 5%, var(--border) 40%, var(--border) 60%, transparent 95%);
  margin-bottom: 1.8em;
  opacity: 0.6;
}
/* Slightly softer muted tone for story body on light theme for eye comfort */
[data-theme="light"] .story-text { color: #2a2318; }