:root {
  /* Brand */
  --blue: #2f8fe8;
  --blue-light: #4aa3f0;
  --blue-dark: #1f74c4;
  --blue-soft: #e8f4fc;
  --accent: #7b5cf0;

  /* UI */
  --text: #1c222b;
  --muted: #8a929b;
  --line: #e8edf2;
  --bg: #d4dee9;
  --white: #ffffff;
  --surface: #ffffff;
  --surface-muted: #f4f7fb;
  --ring-track: #e2e8ef;
  --on-primary: #ffffff;
  --icon-bg: #f1f5f8;
  --icon-text: #39434e;
  --input-bg: #fafcfd;
  --input-text: #303841;
  --nav-bg: rgba(255, 255, 255, 0.96);
  --toast-bg: rgba(38, 50, 61, 0.88);

  /* Semantic */
  --success: #1ea878;
  --success-strong: #148b66;
  --success-bg: #eafaf4;
  --success-border: #b6e9d4;
  --danger: #e05a66;
  --danger-strong: #d24b56;
  --danger-text: #c43b48;
  --danger-bg: #fff0f1;
  --danger-border: #f0c0c5;
  --warning: #ff8a3d;
  --warning-strong: #e67a2a;
  --star: #e6a800;

  --shadow: 0 8px 24px rgba(24, 39, 60, 0.1);
  --radius: 16px;
  --switch-track: #d5dbe3;
  font-family: "Segoe UI", "Khmer OS Battambang", "Noto Sans Khmer", system-ui, sans-serif;
  color: var(--text);
  color-scheme: light;
}

html[data-theme="dark"] {
  --blue: #4aa3f0;
  --blue-light: #5eb0f5;
  --blue-dark: #2f8fe8;
  --blue-soft: #1a2f45;
  --accent: #9b7cf8;

  --text: #e8edf3;
  --muted: #9aa3ae;
  --line: #2a3440;
  --bg: #06090e;
  --white: #141c26;
  --surface: #1b2430;
  --surface-muted: #121820;
  --ring-track: #2a3440;
  --icon-bg: #243040;
  --icon-text: #e8edf3;
  --input-bg: #121820;
  --input-text: #e8edf3;
  --nav-bg: rgba(21, 28, 36, 0.96);
  --toast-bg: rgba(21, 28, 36, 0.92);

  --success-bg: #14352c;
  --success-border: #1ea87855;
  --success-text: #6dffb0;
  --danger-bg: #3a1c22;
  --danger-border: #e05a6655;
  --danger-text: #ff8a94;

  --shadow: 0 8px 24px rgba(0, 0, 0, 0.35);
  color-scheme: dark;
}

* { box-sizing: border-box; }
html, body, #app { margin: 0; height: 100%; }
html { height: 100%; }
body {
  min-height: 100dvh;
  height: 100dvh;
  overflow: hidden;
  background: var(--bg);
  display: grid;
  place-items: center;
  padding: 0;
  color: var(--text);
  transition: background 0.25s ease, color 0.25s ease;
}
#app {
  width: 100%;
  height: 100%;
  display: grid;
  place-items: center;
}
button, input, textarea { font: inherit; }
button { cursor: pointer; }
button:disabled { opacity: 0.45; cursor: default; }

/*
  Frame size: 9:16 (base 1080 × 1920)
  Edge-to-edge — no outer padding.
*/
.phone {
  --max-h: min(1920px, 100dvh);
  --max-w: min(1080px, 100vw);
  --w: min(var(--max-w), calc(var(--max-h) * 9 / 16));
  --h: calc(var(--w) * 16 / 9);

  position: relative;
  width: var(--w);
  height: var(--h);
  aspect-ratio: 9 / 16;
  overflow: hidden;
  background: var(--white);
  border-radius: 0;
  box-shadow:
    0 0 0 1px color-mix(in srgb, var(--line) 65%, transparent),
    0 18px 50px rgba(24, 39, 60, 0.16);
}

.screen {
  height: 100%;
  padding: max(20px, env(safe-area-inset-top)) 22px 96px;
  overflow-y: auto;
  scrollbar-width: none;
  animation: fade-in 0.22s ease;
}
.screen::-webkit-scrollbar { display: none; }
.quiz, .create, .loading, .complete, .settings, .howto, .search, .all-decks { padding-bottom: 28px; }

/* Home: fit 9:16 — no scroll, 4 decks */
.screen.home {
  display: flex;
  flex-direction: column;
  overflow: hidden;
  height: 100%;
  padding: max(16px, env(safe-area-inset-top)) 18px 88px;
  overscroll-behavior: none;
}
.screen.home .top,
.screen.home .overview,
.screen.home .heading { flex: 0 0 auto; }
.screen.home .overview { margin-bottom: 14px; }
.screen.home .heading { margin-bottom: 10px; }
.screen.home .heading h1 { font-size: 22px; }
.screen.home .decks {
  flex: 1 1 auto;
  min-height: 0;
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  grid-template-rows: repeat(2, minmax(0, 1fr));
  gap: 10px 10px;
  padding-bottom: 0;
  overflow: hidden;
}
.screen.home .deck {
  min-height: 0;
  display: flex;
  flex-direction: column;
}
.screen.home .art {
  flex: 1 1 auto;
  height: auto;
  min-height: 72px;
}
.screen.home .deck-copy { padding: 8px 10px; }
.screen.home .deck-copy strong { font-size: 14px; }
.screen.home .deck-copy span { font-size: 11px; }

.see-more {
  border: 0;
  background: none;
  color: var(--blue);
  font-size: 14px;
  font-weight: 700;
  padding: 4px 0;
}
.see-more[hidden] { display: none; }

.screen.all-decks .decks.all {
  grid-template-rows: none;
  overflow-y: auto;
  padding-bottom: 12px;
  scrollbar-width: none;
}
.screen.all-decks .decks.all::-webkit-scrollbar { display: none; }
.screen.all-decks .art { height: 96px; }

/* Quiz: fit 9:16 — no scroll */
.screen.quiz {
  display: flex;
  flex-direction: column;
  overflow: hidden;
  padding: max(12px, env(safe-area-inset-top)) 16px 16px;
  padding-bottom: 16px;
  height: 100%;
  overscroll-behavior: none;
  touch-action: manipulation;
}
.screen.quiz .page-head { margin-bottom: 10px; flex: 0 0 auto; }
.screen.quiz .quiz-panel {
  flex: 0 0 auto;
  padding: 10px 12px;
  margin-bottom: 10px;
  box-shadow: none;
}
.screen.quiz .quiz-meta { margin-bottom: 6px; font-size: 12px; }
.screen.quiz .study-progress { height: 5px; margin-bottom: 0; }
.screen.quiz .q-card {
  flex: 0 1 auto;
  padding: 14px 14px;
  margin-bottom: 10px;
  border-radius: 14px;
  box-shadow: 0 6px 16px rgba(29, 49, 72, 0.06);
  min-height: 0;
}
.screen.quiz .q-label { margin-bottom: 6px; font-size: 12px; }
.screen.quiz .q-ico { width: 18px; height: 18px; font-size: 11px; }
.screen.quiz .q-card h2 {
  font-size: clamp(18px, 4.8vw, 24px);
  line-height: 1.3;
}
.screen.quiz .choose-label {
  flex: 0 0 auto;
  margin-bottom: 6px;
  font-size: 12px;
}
.screen.quiz .options {
  flex: 1 1 auto;
  display: grid;
  grid-template-rows: repeat(4, minmax(0, 1fr));
  gap: 8px;
  margin-bottom: 0;
  min-height: 0;
}
.screen.quiz .option {
  padding: 10px 12px;
  border-radius: 12px;
  min-height: 0;
}
.screen.quiz .opt-text {
  font-size: 14px;
  line-height: 1.25;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}
.screen.quiz .feedback {
  flex: 0 0 auto;
  margin-top: 8px;
  padding: 8px 12px;
  font-size: 13px;
}

@keyframes fade-in {
  from { opacity: 0; transform: translateY(8px); }
  to { opacity: 1; transform: none; }
}

/* Home */
.top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 18px;
}
.brand {
  font-size: 20px;
  font-weight: 800;
  letter-spacing: -0.03em;
}

.overview { margin-bottom: 22px; }
.overview-card {
  display: grid;
  grid-template-columns: 110px 1fr;
  gap: 12px;
  align-items: center;
  padding: 14px;
  border-radius: 20px;
  background:
    linear-gradient(145deg, color-mix(in srgb, var(--blue) 8%, var(--surface)) 0%, var(--surface) 55%);
  border: 1px solid color-mix(in srgb, var(--blue) 14%, var(--line));
  box-shadow: 0 10px 28px rgba(24, 55, 100, 0.06);
}
.stat-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 6px;
}
.stat {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 8px 10px;
  border-radius: 12px;
  background: color-mix(in srgb, var(--white) 70%, var(--surface-muted));
  border: 1px solid var(--line);
  color: var(--muted);
}
.stat-text {
  min-width: 0;
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
}
.stat-text span {
  font-size: 12px;
  font-weight: 600;
  line-height: 1.2;
  white-space: nowrap;
  overflow: visible;
  text-overflow: unset;
}
.stat-text strong {
  color: var(--text);
  font-weight: 800;
  font-size: 15px;
  line-height: 1.1;
  letter-spacing: -0.02em;
}
.ring {
  --value: 0;
  position: relative;
  width: 100%;
  aspect-ratio: 1;
  border-radius: 50%;
  display: grid;
  place-items: center;
  background:
    conic-gradient(
      from -90deg,
      var(--blue) 0deg,
      var(--blue) calc(var(--value) * 3.6deg),
      var(--ring-track) calc(var(--value) * 3.6deg),
      var(--ring-track) 360deg
    );
  box-shadow: inset 0 0 0 1px color-mix(in srgb, var(--blue) 10%, transparent);
}
.ring::before {
  content: "";
  position: absolute;
  inset: 11px;
  border-radius: 50%;
  background: var(--surface);
  box-shadow: 0 4px 14px rgba(24, 55, 100, 0.06);
}
.ring-copy { position: relative; text-align: center; z-index: 1; }
.ring-copy strong {
  display: block;
  font-size: clamp(26px, 7vw, 34px);
  font-weight: 800;
  letter-spacing: -0.04em;
  line-height: 1;
  color: var(--text);
}
.ring-copy small {
  font-size: 0.45em;
  font-weight: 700;
  color: var(--blue);
}
.ring-copy span {
  display: block;
  margin-top: 5px;
  color: var(--muted);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.02em;
}

.overview-side {
  min-width: 0;
  display: flex;
  flex-direction: column;
  gap: 10px;
}
.stat.due {
  background: color-mix(in srgb, var(--warning) 8%, var(--surface));
  border-color: color-mix(in srgb, var(--warning) 22%, var(--line));
}
.stat.due .stat-ico {
  color: var(--warning-strong);
  background: color-mix(in srgb, var(--warning) 16%, transparent);
}
.stat-ico {
  flex: 0 0 30px;
  width: 30px;
  height: 30px;
  border-radius: 10px;
  display: grid;
  place-items: center;
  color: var(--blue);
  background: var(--blue-soft);
}
.stat-ico svg { display: block; }

.primary {
  width: 100%;
  border: 0;
  border-radius: 999px;
  padding: 13px 18px;
  color: var(--on-primary);
  background: linear-gradient(135deg, var(--blue-light), var(--blue-dark));
  font-weight: 800;
  letter-spacing: 0.04em;
  box-shadow: 0 8px 18px rgba(47, 143, 232, 0.28);
  transition: 0.18s;
}
.primary:hover:not(:disabled) {
  filter: brightness(1.05);
  transform: translateY(-1px);
}
.learn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  margin-top: 0;
}
.learn svg { flex: 0 0 auto; }

html[data-theme="dark"] .overview-card {
  background: linear-gradient(145deg, #1a2838, var(--surface));
  border-color: var(--line);
}
html[data-theme="dark"] .ring::before { background: var(--surface); }
html[data-theme="dark"] .stat {
  background: var(--surface-muted);
  border-color: var(--line);
}
html[data-theme="dark"] .stat.due {
  background: color-mix(in srgb, var(--warning) 12%, var(--surface-muted));
}

.heading {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 14px;
}
.heading h1 { margin: 0; font-size: 26px; font-weight: 800; }

.decks {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px 14px;
  padding-bottom: 12px;
}
.deck {
  overflow: hidden;
  border: 0;
  border-radius: 14px;
  padding: 0;
  text-align: left;
  background: var(--surface);
  box-shadow: var(--shadow);
  transition: 0.2s;
}
.deck:hover { transform: translateY(-2px); }
.art {
  position: relative;
  height: 108px;
  overflow: hidden;
  background-color: var(--ring-track);
  background-size: cover;
  background-position: center;
  background-repeat: no-repeat;
}
.art.physics { background-image: url("/assets/decks/physics.webp"); }
.art.math { background-image: url("/assets/decks/math.webp"); }
.art.chem { background-image: url("/assets/decks/chem.webp"); }
.art.psych { background-image: url("/assets/decks/psych.webp"); }
.art.tech { background-image: url("/assets/decks/tech.webp"); }
.art.english { background-image: url("/assets/decks/english.webp"); }
.art.food { background-image: url("/assets/decks/food.webp"); }
.art.geo { background-image: url("/assets/decks/geo.webp"); }
.art.bio { background-image: url("/assets/decks/bio.webp"); }
.art.default { background-image: url("/assets/decks/default.webp"); }

.deck-copy { padding: 12px; }
.deck-copy strong {
  display: block;
  font-size: 16px;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.deck-copy span {
  display: block;
  margin-top: 4px;
  color: var(--muted);
  font-size: 12px;
}
.deck-copy em {
  font-style: normal;
  color: var(--blue);
  font-weight: 600;
}

/* Bottom nav */
.bottom {
  position: absolute;
  left: 0; right: 0; bottom: 0;
  height: 72px;
  z-index: 5;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  align-items: center;
  border-top: 1px solid var(--line);
  background: var(--nav-bg);
  backdrop-filter: blur(8px);
  padding-bottom: env(safe-area-inset-bottom);
}
.nav {
  border: 0;
  background: none;
  color: var(--muted);
  display: grid;
  place-items: center;
  gap: 3px;
  font-size: 12px;
  font-weight: 600;
  line-height: 1.15;
}
.nav svg { width: 22px; height: 22px; }
.nav.active { color: var(--blue); }
.nav-spacer { display: none; }
.fab {
  position: absolute;
  right: 18px;
  bottom: 88px;
  z-index: 8;
  width: 56px;
  height: 56px;
  border: 0;
  border-radius: 50%;
  color: var(--on-primary);
  background: var(--blue);
  font-size: 32px;
  font-weight: 300;
  line-height: 1;
  box-shadow: 0 8px 20px rgba(21, 46, 73, 0.28);
}

/* Shared page head */
.page-head {
  display: grid;
  grid-template-columns: 64px 1fr 64px;
  align-items: center;
  margin-bottom: 18px;
}
.page-head h1 {
  margin: 0;
  text-align: center;
  font-size: 20px;
  font-weight: 800;
}
.text-btn {
  border: 0;
  background: none;
  color: var(--blue);
  font-weight: 700;
  font-size: 16px;
  justify-self: start;
  padding: 0;
}
.badge-btn {
  justify-self: end;
  position: relative;
  width: 36px;
  height: 36px;
  border: 0;
  border-radius: 10px;
  background: var(--blue-soft);
  color: var(--blue);
  font-weight: 700;
}
.badge-btn .dot {
  position: absolute;
  top: -3px; right: -3px;
  width: 14px; height: 14px;
  border-radius: 50%;
  background: var(--blue);
  border: 2px solid var(--surface);
}
.icon {
  width: 40px;
  height: 40px;
  border: 0;
  border-radius: 50%;
  background: var(--icon-bg);
  color: var(--icon-text);
  font-size: 24px;
}

/* Quiz */
.quiz-panel {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 14px 14px 12px;
  margin-bottom: 18px;
  box-shadow: 0 4px 14px rgba(20, 40, 70, 0.04);
}
.quiz-meta {
  display: flex;
  justify-content: space-between;
  font-size: 13px;
  color: var(--muted);
  font-weight: 600;
  margin-bottom: 10px;
}
.stars { color: var(--star); }
.study-progress {
  height: 6px;
  border-radius: 99px;
  overflow: hidden;
  background: var(--ring-track);
  margin-bottom: 10px;
}
.study-progress span {
  display: block;
  height: 100%;
  background: linear-gradient(90deg, var(--blue), var(--accent));
  border-radius: inherit;
  transition: width 0.25s ease;
}
.quiz-sub {
  display: grid;
  gap: 4px;
  color: var(--muted);
  font-size: 12px;
}

.q-card {
  border: 1px solid var(--line);
  border-radius: 18px;
  padding: 22px 20px;
  margin-bottom: 18px;
  background: var(--surface);
  box-shadow: 0 12px 28px rgba(29, 49, 72, 0.08), 0 0 0 4px rgba(80, 120, 220, 0.04);
}
.q-label {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  color: var(--blue);
  font-weight: 800;
  font-size: 13px;
  margin-bottom: 10px;
}
.q-ico {
  width: 22px;
  height: 22px;
  border-radius: 50%;
  display: grid;
  place-items: center;
  background: var(--blue);
  color: var(--on-primary);
  font-size: 13px;
  font-weight: 800;
}
.q-card h2 {
  margin: 0;
  font-size: clamp(24px, 6vw, 32px);
  line-height: 1.25;
  letter-spacing: -0.02em;
}

.choose-label {
  color: var(--muted);
  font-size: 13px;
  margin-bottom: 10px;
  font-weight: 600;
}
.options { display: grid; gap: 10px; margin-bottom: 18px; }
.option {
  display: flex;
  align-items: center;
  gap: 12px;
  width: 100%;
  border: 1.5px solid var(--line);
  border-radius: 14px;
  padding: 12px 14px;
  background: var(--surface);
  text-align: left;
  transition: 0.15s;
}
.option:hover:not(:disabled) { border-color: color-mix(in srgb, var(--blue) 35%, var(--line)); }
.option.selected {
  border-color: var(--blue);
  background: var(--blue-soft);
}
.option.correct {
  border-color: var(--success);
  background: var(--success-bg);
}
.option.wrong {
  border-color: var(--danger);
  background: var(--danger-bg);
}
.letter {
  flex: 0 0 28px;
  height: 28px;
  border-radius: 50%;
  display: grid;
  place-items: center;
  background: var(--bg);
  color: var(--muted);
  font-weight: 800;
  font-size: 13px;
}
.option.selected .letter {
  background: var(--blue);
  color: var(--on-primary);
}
.option.correct .letter { background: var(--success); color: var(--on-primary); }
.option.wrong .letter { background: var(--danger); color: var(--on-primary); }
.opt-text { font-weight: 600; font-size: 15px; }
.submit {
  background: linear-gradient(90deg, var(--blue), var(--accent));
  margin-top: auto;
}

/* Create */
.create-hero { text-align: center; margin: 8px auto 22px; }
.upload {
  width: 72px;
  height: 72px;
  margin: 0 auto 14px;
  display: grid;
  place-items: center;
  border-radius: 22px;
  color: var(--blue);
  background: var(--blue-soft);
  font-size: 30px;
}
.create-hero h2 { margin: 0 0 6px; font-size: 20px; }
.create-hero p { margin: 0; color: var(--muted); line-height: 1.45; font-size: 14px; }
.field-label {
  display: block;
  margin: 0 0 6px;
  font-size: 13px;
  font-weight: 700;
  color: var(--muted);
}
.field, .lesson {
  width: 100%;
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 13px 14px;
  color: var(--input-text);
  background: var(--input-bg);
  outline: none;
  margin-bottom: 14px;
}
.field:focus, .lesson:focus {
  border-color: var(--blue);
  box-shadow: 0 0 0 3px rgba(47, 143, 232, 0.15);
}
.lesson {
  height: 150px;
  resize: none;
  line-height: 1.5;
}
.generate { margin-top: 4px; }

/* Loading / complete */
.loading {
  display: grid;
  place-items: center;
  text-align: center;
}
.loader {
  width: 64px;
  height: 64px;
  margin: 0 auto 20px;
  border: 6px solid var(--line);
  border-top-color: var(--blue);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }
.loading h2 { margin: 0 0 8px; }
.loading p { color: var(--muted); }

.complete {
  text-align: center;
  padding: max(24px, env(safe-area-inset-top)) 20px 24px;
  position: relative;
  display: flex;
  flex-direction: column;
  justify-content: center;
  height: 100%;
  overflow: hidden;
}
.complete-card {
  position: relative;
  margin-bottom: 20px;
}
.complete-ring {
  --value: 0;
  position: relative;
  width: 120px;
  height: 120px;
  margin: 0 auto 18px;
  border-radius: 50%;
  display: grid;
  place-items: center;
  background:
    conic-gradient(
      from -90deg,
      var(--blue) 0deg,
      var(--blue) calc(var(--value) * 3.6deg),
      var(--ring-track) calc(var(--value) * 3.6deg),
      var(--ring-track) 360deg
    );
}
.complete-ring::before {
  content: "";
  position: absolute;
  width: 96px;
  height: 96px;
  border-radius: 50%;
  background: var(--surface);
}
.complete-ring-copy {
  position: relative;
  z-index: 1;
  text-align: center;
}
.complete-ring-copy strong {
  display: block;
  font-size: 32px;
  font-weight: 800;
  line-height: 1;
}
.complete-ring-copy small { font-size: 0.5em; color: var(--blue); }
.complete-ring-copy span {
  display: block;
  margin-top: 4px;
  font-size: 11px;
  color: var(--muted);
  font-weight: 600;
}
.complete h1 {
  position: relative;
  margin: 0 0 8px;
  font-size: 24px;
}
.complete-msg {
  position: relative;
  margin: 0 0 6px;
  color: var(--blue);
  font-weight: 700;
  font-size: 15px;
}
.complete-deck {
  position: relative;
  margin: 0 0 18px;
  color: var(--muted);
  font-size: 14px;
}
.complete-stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 10px;
  margin-bottom: 8px;
}
.complete-stat {
  padding: 12px 8px;
  border-radius: 14px;
  background: var(--surface);
  border: 1px solid var(--line);
}
.complete-stat strong {
  display: block;
  font-size: 22px;
  font-weight: 800;
  line-height: 1.1;
}
.complete-stat span {
  display: block;
  margin-top: 4px;
  font-size: 11px;
  color: var(--muted);
  font-weight: 600;
}
.complete-stat.ok strong { color: var(--success-strong); }
.complete-stat.bad strong { color: var(--danger-strong); }
.complete .primary { position: relative; margin-bottom: 8px; }
.complete .ghost { position: relative; }
.confetti {
  position: absolute;
  inset: 0 0 auto 0;
  height: 180px;
  background-image:
    radial-gradient(circle, #ff5a5a 2px, transparent 3px),
    radial-gradient(circle, #ffd166 2px, transparent 3px),
    radial-gradient(circle, #06d6a0 2px, transparent 3px),
    radial-gradient(circle, #2f8fe8 2px, transparent 3px);
  background-size: 48px 48px, 56px 56px, 40px 40px, 64px 64px;
  background-position: 10% 20%, 70% 30%, 40% 10%, 85% 50%;
  opacity: 0.85;
  pointer-events: none;
  animation: confetti 1.2s ease both;
}
@keyframes confetti {
  from { opacity: 0; transform: translateY(-12px); }
  to { opacity: 0.85; transform: none; }
}
.check {
  position: relative;
  width: 88px;
  height: 88px;
  margin: 0 auto 20px;
  border-radius: 50%;
  display: grid;
  place-items: center;
  color: var(--on-primary);
  background: var(--blue);
  font-size: 40px;
  box-shadow: 0 10px 24px rgba(47, 143, 232, 0.35);
}
.complete h1 { position: relative; margin: 0 0 10px; }
.complete p {
  position: relative;
  color: var(--muted);
  line-height: 1.6;
  margin: 0 0 24px;
}
.ghost {
  width: 100%;
  margin-top: 10px;
  border: 0;
  background: none;
  color: var(--muted);
  font-weight: 700;
  padding: 12px;
}

.toast {
  position: absolute;
  left: 50%;
  bottom: 88px;
  z-index: 20;
  transform: translateX(-50%);
  width: max-content;
  max-width: 85%;
  padding: 10px 16px;
  border-radius: 99px;
  color: var(--on-primary);
  background: var(--toast-bg);
  box-shadow: var(--shadow);
  animation: toast 1.5s both;
  font-size: 13px;
}
@keyframes toast {
  0%, 100% { opacity: 0; transform: translate(-50%, 8px); }
  15%, 80% { opacity: 1; transform: translate(-50%); }
}

@media (max-height: 740px) {
  .art { height: 88px; }
  .q-card h2 { font-size: 22px; }
  .overview { margin-bottom: 18px; }
}

/* Settings */
.settings-group {
  margin-bottom: 22px;
  padding: 4px 0 8px;
}
.settings-label {
  font-size: 12px;
  font-weight: 800;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--muted);
  margin-bottom: 10px;
}
.settings-row {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  padding: 14px 16px;
  border-radius: 14px;
  background: var(--surface);
  border: 1px solid var(--line);
  cursor: pointer;
}
.settings-row.static { cursor: default; padding-left: 2px; padding-right: 2px; border: 0; background: transparent; }
.settings-row strong { display: block; font-size: 15px; }
.settings-row span { display: block; margin-top: 3px; color: var(--muted); font-size: 12px; }
.settings-row input[type="checkbox"] {
  position: absolute;
  opacity: 0;
  width: 0;
  height: 0;
}
.switch {
  flex: 0 0 48px;
  width: 48px;
  height: 28px;
  border-radius: 999px;
  background: var(--switch-track);
  position: relative;
  transition: 0.2s;
}
.switch::after {
  content: "";
  position: absolute;
  top: 3px;
  left: 3px;
  width: 22px;
  height: 22px;
  border-radius: 50%;
  background: var(--surface);
  box-shadow: 0 2px 6px rgba(0, 0, 0, 0.2);
  transition: 0.2s;
}
.settings-row input:checked + .switch { background: var(--blue); }
.settings-row input:checked + .switch::after { transform: translateX(20px); }

.seg {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 8px;
  padding: 4px;
  border-radius: 14px;
  background: color-mix(in srgb, var(--line) 70%, transparent);
  border: 1px solid var(--line);
}
.seg-btn {
  border: 0;
  border-radius: 11px;
  padding: 12px 8px;
  background: transparent;
  color: var(--muted);
  font-weight: 700;
  font-size: 13px;
  transition: 0.15s;
}
.seg-btn.active {
  background: var(--surface);
  color: var(--blue);
  box-shadow: var(--shadow);
}

.settings-link {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 16px;
  border-radius: 14px;
  border: 1px solid var(--line);
  background: var(--surface);
  text-align: left;
  color: var(--text);
}
.settings-link span { color: var(--muted); font-size: 20px; font-weight: 300; }

.howto-list {
  list-style: none;
  margin: 0 0 24px;
  padding: 0;
  display: grid;
  gap: 12px;
}
.howto-list li {
  display: flex;
  gap: 12px;
  align-items: flex-start;
  padding: 14px;
  border-radius: 14px;
  border: 1px solid var(--line);
  background: var(--surface);
}
.step-num {
  flex: 0 0 28px;
  height: 28px;
  border-radius: 50%;
  display: grid;
  place-items: center;
  background: var(--blue-soft);
  color: var(--blue);
  font-weight: 800;
  font-size: 13px;
}
.howto-list p {
  margin: 0;
  line-height: 1.45;
  font-size: 14px;
  padding-top: 3px;
}

.dir-chip {
  display: inline-block;
  margin-top: 4px;
  padding: 2px 8px;
  border-radius: 99px;
  background: var(--blue-soft);
  color: var(--blue);
  font-weight: 700;
  font-size: 11px;
  width: fit-content;
}

.feedback {
  margin-top: 14px;
  padding: 12px 14px;
  border-radius: 14px;
  font-weight: 700;
  font-size: 14px;
  line-height: 1.4;
  animation: fade-in 0.18s ease;
}
.feedback.ok {
  background: var(--success-bg);
  color: var(--success-strong);
  border: 1px solid var(--success-border);
}
.feedback.bad {
  background: var(--danger-bg);
  color: var(--danger-text);
  border: 1px solid var(--danger-border);
}
.feedback.bad strong {
  color: var(--text);
  font-weight: 800;
}
html[data-theme="dark"] .feedback.ok {
  background: var(--success-bg);
  border-color: var(--success-border);
  color: var(--success-text);
}
html[data-theme="dark"] .feedback.bad {
  background: var(--danger-bg);
  border-color: var(--danger-border);
  color: var(--danger-text);
}
html[data-theme="dark"] .feedback.bad strong { color: var(--text); }

html[data-theme="dark"] .phone {
  box-shadow:
    0 0 0 1px color-mix(in srgb, var(--line) 80%, transparent),
    0 18px 50px rgba(0, 0, 0, 0.45);
}
html[data-theme="dark"] .bottom { background: var(--nav-bg); border-top-color: var(--line); }
html[data-theme="dark"] .deck,
html[data-theme="dark"] .q-card,
html[data-theme="dark"] .quiz-panel,
html[data-theme="dark"] .option {
  background: var(--surface);
  border-color: var(--line);
}
html[data-theme="dark"] .ring::before { background: var(--white); }
html[data-theme="dark"] .icon { background: var(--icon-bg); color: var(--icon-text); }
html[data-theme="dark"] .field,
html[data-theme="dark"] .lesson {
  background: var(--input-bg);
  border-color: var(--line);
  color: var(--input-text);
}
html[data-theme="dark"] .option.selected { background: var(--blue-soft); }
html[data-theme="dark"] .upload { background: var(--blue-soft); }

/* Store */
.screen.store {
  display: flex;
  flex-direction: column;
  overflow: hidden;
  overscroll-behavior: none;
  padding-bottom: 0;
}
.screen.store .page-head,
.screen.store .store-hint {
  flex: 0 0 auto;
}
.screen.store .store-list {
  flex: 1 1 auto;
  min-height: 0;
  overflow-y: auto;
  scrollbar-width: none;
  -webkit-overflow-scrolling: touch;
  padding-bottom: calc(84px + env(safe-area-inset-bottom));
}
.screen.store .store-list::-webkit-scrollbar { display: none; }

.page-head.single {
  grid-template-columns: 1fr;
}
.page-head.single h1 { text-align: left; }
.store-hint {
  margin: -8px 0 12px;
  color: var(--muted);
  font-size: 14px;
  line-height: 1.4;
}
.store-list { display: grid; gap: 12px; }
.store-card {
  display: grid;
  grid-template-columns: 72px 1fr auto;
  gap: 12px;
  align-items: center;
  padding: 10px;
  border-radius: 16px;
  border: 1px solid var(--line);
  background: var(--surface);
}
.store-card .art {
  height: 64px;
  border-radius: 12px;
}
.store-copy strong { display: block; font-size: 15px; }
.store-copy span {
  display: block;
  margin-top: 2px;
  color: var(--muted);
  font-size: 12px;
  line-height: 1.35;
}
.store-meta { margin-top: 4px !important; color: var(--blue) !important; font-weight: 700; }
.store-btn {
  border: 0;
  border-radius: 999px;
  padding: 10px 14px;
  background: var(--blue);
  color: var(--on-primary);
  font-weight: 800;
  font-size: 13px;
  white-space: nowrap;
}
.store-btn.owned {
  background: color-mix(in srgb, var(--line) 80%, var(--blue-soft));
  color: var(--muted);
}

/* Search */
.search-box {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 12px 14px;
  border-radius: 14px;
  border: 1px solid var(--line);
  background: var(--surface);
  margin-bottom: 18px;
}
.search-ico { color: var(--muted); font-size: 18px; }
.search-input {
  flex: 1;
  border: 0;
  outline: none;
  background: transparent;
  color: var(--text);
  font-size: 15px;
  min-width: 0;
}
.empty-msg {
  text-align: center;
  color: var(--muted);
  margin-top: 40px;
}
.search-row {
  width: 100%;
  display: flex;
  align-items: center;
  gap: 12px;
  text-align: left;
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 10px 12px;
  background: var(--surface);
  color: var(--text);
  margin-bottom: 8px;
}
.search-row strong { display: block; font-size: 14px; }
.search-row span {
  display: block;
  margin-top: 2px;
  color: var(--muted);
  font-size: 12px;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  max-width: 220px;
}
.search-row em {
  margin-left: auto;
  font-style: normal;
  color: var(--blue);
  font-weight: 800;
  font-size: 12px;
}
.art.tiny {
  flex: 0 0 44px;
  width: 44px;
  height: 44px;
  border-radius: 10px;
}
.search-q { min-width: 0; flex: 1; }