/* Quizzer stylesheet. Design tokens first, then base, layout, components, views. */

:root {
  color-scheme: light;

  --page: #f9f9f7;
  --surface: #fcfcfb;
  --surface-2: #f1f0ec;
  --surface-3: #e8e7e1;
  --ink: #0b0b0b;
  --ink-2: #52514e;
  --ink-muted: #6d6c66;
  --line: #e1e0d9;
  --line-strong: #c3c2b7;

  --accent: #256bc0;
  --accent-hover: #215fab;
  --accent-ink: #ffffff;
  --accent-soft: #e7f0fc;

  --good: #0ca30c;
  --good-ink: #006300;
  --warning: #fab219;
  --critical: #d03b3b;
  --critical-ink: #b02f2f;

  --focus: 0 0 0 3px rgba(37, 107, 192, 0.35);
  --shadow-1: 0 1px 2px rgba(11, 11, 11, 0.06), 0 1px 1px rgba(11, 11, 11, 0.04);
  --shadow-2: 0 6px 20px rgba(11, 11, 11, 0.08), 0 2px 6px rgba(11, 11, 11, 0.05);

  --radius: 14px;
  --radius-sm: 9px;
  --gap: 16px;
  --sans: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;

  /* Data visualisation roles. Ordinal blue ramp, validated light to dark. */
  --viz-tier-1: #86b6ef;
  --viz-tier-2: #3987e5;
  --viz-tier-3: #1c5cab;
  --viz-tier-4: #0d366b;
  --viz-series: #2a78d6;
  --viz-empty: #e8e7e1;
  --viz-grid: #e1e0d9;
  --viz-axis: #c3c2b7;
}

/* The dark tokens are for the screen only: printed pages keep the light
   ones, since paper stays white. */

@media screen and (prefers-color-scheme: dark) {
  :root:where(:not([data-theme="light"])) {
    color-scheme: dark;

    --page: #0d0d0d;
    --surface: #1a1a19;
    --surface-2: #232321;
    --surface-3: #2c2c2a;
    --ink: #ffffff;
    --ink-2: #c3c2b7;
    --ink-muted: #8c8b85;
    --line: #2c2c2a;
    --line-strong: #383835;

    --accent: #438de6;
    --accent-hover: #5598e7;
    --accent-ink: #06101d;
    --accent-soft: #15243a;

    --good: #0ca30c;
    --good-ink: #0ca30c;
    --critical: #d03b3b;
    --critical-ink: #e66767;

    --shadow-1: 0 1px 2px rgba(0, 0, 0, 0.5);
    --shadow-2: 0 8px 24px rgba(0, 0, 0, 0.55);

    --viz-tier-1: #184f95;
    --viz-tier-2: #2a78d6;
    --viz-tier-3: #6da7ec;
    --viz-tier-4: #b7d3f6;
    --viz-series: #3987e5;
    --viz-empty: #2c2c2a;
    --viz-grid: #2c2c2a;
    --viz-axis: #383835;
  }
}

@media screen {
  :root[data-theme="dark"] {
    color-scheme: dark;

    --page: #0d0d0d;
    --surface: #1a1a19;
    --surface-2: #232321;
    --surface-3: #2c2c2a;
    --ink: #ffffff;
    --ink-2: #c3c2b7;
    --ink-muted: #8c8b85;
    --line: #2c2c2a;
    --line-strong: #383835;

    --accent: #438de6;
    --accent-hover: #5598e7;
    --accent-ink: #06101d;
    --accent-soft: #15243a;

    --good: #0ca30c;
    --good-ink: #0ca30c;
    --critical: #d03b3b;
    --critical-ink: #e66767;

    --shadow-1: 0 1px 2px rgba(0, 0, 0, 0.5);
    --shadow-2: 0 8px 24px rgba(0, 0, 0, 0.55);

    --viz-tier-1: #184f95;
    --viz-tier-2: #2a78d6;
    --viz-tier-3: #6da7ec;
    --viz-tier-4: #b7d3f6;
    --viz-series: #3987e5;
    --viz-empty: #2c2c2a;
    --viz-grid: #2c2c2a;
    --viz-axis: #383835;
  }
}

/* Base */

*, *::before, *::after { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  background: var(--page);
  color: var(--ink);
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.55;
}

h1, h2, h3 { line-height: 1.25; margin: 0 0 0.4em; font-weight: 650; letter-spacing: -0.012em; }
h1 { font-size: clamp(1.6rem, 1.2rem + 1.6vw, 2.1rem); }
h2 { font-size: 1.3rem; }
h3 { font-size: 1.05rem; }
p { margin: 0 0 0.9em; }
p:last-child { margin-bottom: 0; }

a { color: var(--accent); text-decoration-thickness: 1px; text-underline-offset: 2px; }
a:hover { color: var(--accent-hover); }

:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }

.sr-only {
  position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px;
  overflow: hidden; clip-path: inset(50%); white-space: nowrap; border: 0;
}

.skip-link {
  position: absolute; left: 8px; top: -60px; z-index: 40;
  background: var(--accent); color: var(--accent-ink);
  padding: 10px 16px; border-radius: var(--radius-sm); font-weight: 600;
  text-decoration: none; transition: top 0.15s;
}
.skip-link:focus { top: 8px; color: var(--accent-ink); }

.noscript { max-width: 640px; margin: 40px auto; padding: 0 16px; }

/* Top bar */

.topbar {
  position: sticky; top: 0; z-index: 30;
  background: var(--surface);
  border-bottom: 1px solid var(--line);
}
.topbar-inner {
  max-width: 1120px; margin: 0 auto; padding: 10px 16px;
  display: flex; align-items: center; gap: 18px;
}
.brand {
  display: inline-flex; align-items: center; gap: 9px;
  color: var(--ink); text-decoration: none; font-weight: 700; font-size: 1.12rem;
  letter-spacing: -0.02em; flex: 0 0 auto;
}
.brand-mark { width: 27px; height: 27px; fill: none; stroke: var(--accent); stroke-width: 2.2; }
.brand-mark-front { fill: var(--surface); }
.topnav { display: flex; gap: 4px; flex: 1 1 auto; min-width: 0; }
.topnav a {
  padding: 7px 12px; border-radius: 999px; color: var(--ink-2);
  text-decoration: none; font-weight: 550; font-size: 0.94rem; white-space: nowrap;
}
.topnav a:hover { background: var(--surface-2); color: var(--ink); }
.topnav a[aria-current="page"] { background: var(--accent-soft); color: var(--accent); }
.topbar-tools { display: flex; align-items: center; gap: 8px; flex: 0 0 auto; }
.field-inline { display: inline-flex; align-items: center; }

/* Shown while changes cannot be saved. */
.save-alert {
  margin: 0; padding: 10px 16px; text-align: center; font-weight: 600; font-size: 0.92rem;
  color: var(--critical-ink); border-bottom: 1px solid var(--critical);
  background: color-mix(in srgb, var(--critical) 10%, var(--surface));
}

/* Layout */

.main { flex: 1 0 auto; outline: none; }
.container { max-width: 1120px; margin: 0 auto; padding: 28px 16px 48px; }
.container-narrow { max-width: 760px; }
.stack { display: flex; flex-direction: column; gap: var(--gap); }
.row { display: flex; align-items: center; gap: 10px; flex-wrap: wrap; }
.row-between { display: flex; align-items: center; justify-content: space-between; gap: 12px; flex-wrap: wrap; }

.footer {
  flex: 0 0 auto; border-top: 1px solid var(--line);
  background: var(--surface); color: var(--ink-muted); font-size: 0.86rem;
}
.footer-inner {
  max-width: 1120px; margin: 0 auto; padding: 20px 16px;
  display: flex; justify-content: space-between; gap: 12px; flex-wrap: wrap;
}
.footer p { margin: 0; }

/* Buttons */

.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  padding: 9px 16px; border-radius: 999px;
  border: 1px solid var(--line-strong); background: var(--surface); color: var(--ink);
  font: inherit; font-weight: 600; font-size: 0.94rem; line-height: 1.3;
  cursor: pointer; text-decoration: none; white-space: nowrap;
  transition: background 0.12s, border-color 0.12s, transform 0.06s;
}
.btn:hover { background: var(--surface-2); color: var(--ink); }
.btn:active { transform: translateY(1px); }
.btn:disabled { opacity: 0.45; cursor: not-allowed; transform: none; }
.btn svg { width: 17px; height: 17px; flex: 0 0 auto; }
/* A file picker is a hidden input behind its label: the focus ring the input
   cannot show is drawn on the label instead. */
.sr-only:focus-visible + .btn { outline: 2px solid var(--accent); outline-offset: 2px; }

.btn-primary { background: var(--accent); border-color: var(--accent); color: var(--accent-ink); }
.btn-primary:hover { background: var(--accent-hover); border-color: var(--accent-hover); color: var(--accent-ink); }
.btn-ghost { background: transparent; border-color: transparent; color: var(--ink-2); }
.btn-ghost:hover { background: var(--surface-2); }
.btn-danger { color: var(--critical-ink); border-color: var(--line-strong); }
.btn-danger:hover { background: var(--critical); border-color: var(--critical); color: #fff; }
.btn-lg { padding: 13px 24px; font-size: 1rem; }

.icon-btn {
  display: inline-flex; align-items: center; justify-content: center;
  width: 38px; height: 38px; padding: 0; border-radius: 50%;
  border: 1px solid transparent; background: transparent; color: var(--ink-2);
  cursor: pointer;
}
.icon-btn:hover { background: var(--surface-2); color: var(--ink); }
.icon-btn svg { width: 19px; height: 19px; }

/* Forms */

.field { display: flex; flex-direction: column; gap: 6px; }
.field > span, .field-label { font-size: 0.88rem; font-weight: 600; color: var(--ink-2); }
.field-hint { font-size: 0.82rem; color: var(--ink-muted); }

.input, .textarea, .select {
  width: 100%; padding: 10px 12px; font: inherit; color: var(--ink);
  background: var(--surface); border: 1px solid var(--line-strong);
  border-radius: var(--radius-sm);
}
.input:focus, .textarea:focus, .select:focus { border-color: var(--accent); outline: none; box-shadow: var(--focus); }
.textarea { min-height: 120px; resize: vertical; font-family: var(--sans); }
.select-compact {
  padding: 7px 9px; font: inherit; font-size: 0.88rem; color: var(--ink-2);
  background: var(--surface); border: 1px solid var(--line-strong); border-radius: var(--radius-sm);
}

.checkbox { display: flex; align-items: flex-start; gap: 9px; font-size: 0.94rem; cursor: pointer; }
.checkbox input { margin: 3px 0 0; width: 17px; height: 17px; accent-color: var(--accent); flex: 0 0 auto; }
.checkbox-text { display: flex; flex-direction: column; gap: 2px; }
.checkbox-text small { color: var(--ink-muted); }

/* Panels, chips, tables */

.panel {
  background: var(--surface); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 20px; box-shadow: var(--shadow-1);
}

.chip {
  display: inline-flex; align-items: center; gap: 6px;
  padding: 3px 10px; border-radius: 999px; background: var(--surface-2);
  color: var(--ink-2); font-size: 0.8rem; font-weight: 600;
}
.chip-accent { background: var(--accent-soft); color: var(--accent); }
.chip-due { background: var(--accent); color: var(--accent-ink); }

.table { width: 100%; border-collapse: collapse; font-size: 0.92rem; }
.table th, .table td { padding: 9px 10px; text-align: left; border-bottom: 1px solid var(--line); }
.table th { font-size: 0.8rem; text-transform: uppercase; letter-spacing: 0.04em; color: var(--ink-muted); font-weight: 650; }
.table td.num, .table th.num { text-align: right; font-variant-numeric: tabular-nums; }
.table tr:last-child td { border-bottom: none; }
.table-wrap { overflow-x: auto; }

.empty {
  text-align: center; padding: 48px 20px; color: var(--ink-2);
  border: 1px dashed var(--line-strong); border-radius: var(--radius); background: var(--surface);
}
.empty h2 { color: var(--ink); }
.empty-actions { display: flex; gap: 10px; justify-content: center; flex-wrap: wrap; margin-top: 18px; }

/* Toast */

.toast {
  position: fixed; left: 50%; bottom: 24px; transform: translate(-50%, 16px);
  max-width: min(420px, calc(100vw - 32px));
  background: var(--ink); color: var(--page);
  padding: 11px 18px; border-radius: 999px; font-size: 0.92rem; font-weight: 550;
  box-shadow: var(--shadow-2); opacity: 0; pointer-events: none;
  transition: opacity 0.18s, transform 0.18s; z-index: 50;
}
.toast[data-show="1"] { opacity: 1; transform: translate(-50%, 0); }

/* Home */

.hero {
  display: flex; gap: 28px; align-items: center; justify-content: space-between;
  flex-wrap: wrap; margin-bottom: 26px;
}
.hero-text { flex: 1 1 340px; }
.hero-text h1 { margin-bottom: 8px; }
.hero-text .lede { color: var(--ink-2); font-size: 1.05rem; margin-bottom: 18px; }
.hero-actions { display: flex; gap: 10px; flex-wrap: wrap; }

.kpi-row {
  display: grid; gap: 12px; margin-bottom: 26px;
  grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
}
.stat-tile {
  background: var(--surface); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 14px 16px;
}
.stat-label { font-size: 0.82rem; color: var(--ink-2); font-weight: 600; margin-bottom: 2px; }
.stat-value { font-size: 1.85rem; font-weight: 680; letter-spacing: -0.02em; line-height: 1.1; }
.stat-sub { font-size: 0.82rem; color: var(--ink-muted); margin-top: 2px; }
a.stat-tile {
  display: block; color: inherit; text-decoration: none;
  transition: border-color 0.12s, transform 0.12s;
}
a.stat-tile:hover { border-color: var(--accent); transform: translateY(-2px); color: inherit; }
.stat-label svg { width: 13px; height: 13px; margin-left: 5px; vertical-align: -1px; color: var(--ink-muted); }

.set-grid { display: grid; gap: 14px; grid-template-columns: repeat(auto-fill, minmax(268px, 1fr)); }
.set-card {
  display: flex; flex-direction: column; gap: 10px;
  background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 16px; text-decoration: none; color: inherit; box-shadow: var(--shadow-1);
  transition: border-color 0.12s, box-shadow 0.12s, transform 0.12s;
}
.set-card:hover { border-color: var(--accent); box-shadow: var(--shadow-2); transform: translateY(-2px); color: inherit; }
.set-card h3 { margin: 0; font-size: 1.05rem; }
.set-card p { margin: 0; color: var(--ink-2); font-size: 0.9rem; }
.set-card-meta { display: flex; gap: 8px; flex-wrap: wrap; margin-top: auto; padding-top: 4px; }

.meter { height: 8px; border-radius: 999px; background: var(--viz-empty); overflow: hidden; }
.meter-fill { height: 100%; border-radius: 999px; background: var(--viz-tier-3); }

.search-bar { display: flex; gap: 10px; align-items: center; margin-bottom: 16px; flex-wrap: wrap; }
.search-bar .input { max-width: 320px; }

/* Set detail */

.set-head { margin-bottom: 22px; }
.set-head h1 { margin-bottom: 6px; }
.set-head .lede { color: var(--ink-2); }

.mode-grid { display: grid; gap: 12px; grid-template-columns: repeat(auto-fit, minmax(190px, 1fr)); margin-bottom: 26px; }
.mode-card {
  display: flex; gap: 12px; align-items: flex-start;
  padding: 16px; border-radius: var(--radius); border: 1px solid var(--line);
  background: var(--surface); text-decoration: none; color: inherit; box-shadow: var(--shadow-1);
  transition: border-color 0.12s, transform 0.12s;
}
.mode-card:hover { border-color: var(--accent); transform: translateY(-2px); color: inherit; }
.mode-card[aria-disabled="true"] { opacity: 0.5; pointer-events: none; }
.mode-icon {
  flex: 0 0 auto; width: 38px; height: 38px; border-radius: 10px;
  background: var(--accent-soft); color: var(--accent);
  display: grid; place-items: center;
}
.mode-icon svg { width: 20px; height: 20px; }
.mode-card strong { display: block; font-size: 0.99rem; }
.mode-card small { color: var(--ink-2); font-size: 0.85rem; line-height: 1.4; }

.card-list { display: flex; flex-direction: column; gap: 8px; }
.card-row {
  display: grid; grid-template-columns: 1fr 1fr auto; gap: 14px; align-items: start;
  padding: 12px 14px; background: var(--surface);
  border: 1px solid var(--line); border-radius: var(--radius-sm);
}
.card-row .term { font-weight: 600; }
.card-row .def { color: var(--ink-2); }
.card-row .hint { display: block; font-size: 0.82rem; color: var(--ink-muted); }
.card-row-tools { display: flex; gap: 4px; }

/* Editor */

.editor-row {
  display: grid; grid-template-columns: 26px 1fr 1fr auto; gap: 10px; align-items: start;
  padding: 12px; border: 1px solid var(--line); border-radius: var(--radius-sm); background: var(--surface);
}
.editor-row .idx { padding-top: 10px; color: var(--ink-muted); font-size: 0.85rem; font-variant-numeric: tabular-nums; }
.editor-row-tools { display: flex; gap: 2px; padding-top: 2px; }
.editor-fields { display: flex; flex-direction: column; gap: 6px; }
.symbol-palette { margin-bottom: 12px; }
.symbol-palette summary { cursor: pointer; font-size: 0.86rem; color: var(--ink-2); font-weight: 600; }
.symbols { display: flex; flex-wrap: wrap; gap: 6px; margin-top: 8px; }
.btn-symbol { min-width: 40px; padding: 6px 10px; font-weight: 500; }
.editor-image { display: flex; align-items: center; gap: 6px; }
.editor-image .card-image { margin: 0; }
.btn-image { align-self: flex-start; padding: 5px 10px; font-size: 0.86rem; }

/* Card pictures: whole, never cropped, within the space of the card. */
.card-image { display: block; max-width: 100%; max-height: 220px; margin: 0 auto 10px; border-radius: var(--radius-sm); object-fit: contain; }
.card-image.thumb { max-width: 96px; max-height: 64px; margin: 0 0 6px; }
.card-image[data-missing] { min-width: 48px; min-height: 32px; background: var(--surface-2); }
.match-tile .card-image { max-height: 90px; margin: 0 auto 6px; }
.sticky-actions {
  position: sticky; bottom: 0; z-index: 10;
  display: flex; gap: 10px; align-items: center; flex-wrap: wrap;
  padding: 14px 0; margin-top: 8px;
  background: linear-gradient(to top, var(--page) 70%, transparent);
}

/* Study shell */

.study { max-width: 780px; margin: 0 auto; padding: 24px 16px 48px; }
.study-head { display: flex; align-items: center; gap: 12px; margin-bottom: 14px; }
.study-head h1 { font-size: 1.15rem; margin: 0; flex: 1 1 auto; min-width: 0; }
.study-head .count { color: var(--ink-2); font-size: 0.9rem; font-variant-numeric: tabular-nums; }

.progress { height: 6px; border-radius: 999px; background: var(--surface-3); overflow: hidden; margin-bottom: 22px; }
.progress-fill { height: 100%; background: var(--accent); border-radius: 999px; transition: width 0.25s; }

.study-toolbar { display: flex; gap: 8px; align-items: center; flex-wrap: wrap; margin-bottom: 16px; }
.toggle-btn { font-size: 0.86rem; padding: 6px 12px; }
.toggle-btn[aria-pressed="true"] { background: var(--accent-soft); border-color: var(--accent); color: var(--accent); }

/* Flashcard */

.flashcard-wrap { margin: 0 0 18px; }
.flashcard {
  position: relative; width: 100%;
  perspective: 1400px; background: none; border: none; padding: 0; margin: 0;
  cursor: pointer; font: inherit; color: inherit; display: block; text-align: center;
}
/* Both faces share one grid cell, so the card grows with the longer side
   instead of letting long text spill over the buttons below. */
.flashcard-inner {
  display: grid; min-height: 320px;
  transition: transform 0.45s cubic-bezier(0.2, 0.7, 0.3, 1);
  transform-style: preserve-3d;
}
.flashcard[data-flipped="1"] .flashcard-inner { transform: rotateY(180deg); }
.flashcard-face {
  grid-area: 1 / 1; min-width: 0;
  display: flex; flex-direction: column; align-items: center; justify-content: center;
  gap: 12px; padding: 32px 28px; text-align: center; overflow-wrap: anywhere;
  background: var(--surface); border: 1px solid var(--line);
  border-radius: var(--radius); box-shadow: var(--shadow-1);
  backface-visibility: hidden; -webkit-backface-visibility: hidden;
}
.flashcard-face .side { font-size: 0.78rem; text-transform: uppercase; letter-spacing: 0.06em; color: var(--ink-muted); font-weight: 650; }
.flashcard-face .content { font-size: clamp(1.3rem, 1rem + 2vw, 1.9rem); font-weight: 600; }
.flashcard-face .hint { color: var(--ink-2); font-size: 0.92rem; }
.flashcard-back { transform: rotateY(180deg); }
.flashcard-tools { display: flex; justify-content: flex-end; min-height: 38px; margin-top: 6px; }
.flashcard-foot { font-size: 0.82rem; color: var(--ink-muted); }

.study-nav { display: flex; align-items: center; justify-content: center; gap: 12px; }
.study-nav .count { min-width: 84px; text-align: center; color: var(--ink-2); font-variant-numeric: tabular-nums; }

/* Question modes */

.question { margin-bottom: 20px; }
.question-kind { font-size: 0.78rem; text-transform: uppercase; letter-spacing: 0.06em; color: var(--ink-muted); font-weight: 650; }
.quiz-timer { margin: 0 0 12px; text-align: right; color: var(--ink-2); font-variant-numeric: tabular-nums; }
.quiz-timer[data-low="1"] { color: var(--critical-ink); font-weight: 650; }
.question-prompt {
  font-size: clamp(1.25rem, 1rem + 1.4vw, 1.6rem); font-weight: 600;
  padding: 26px 22px; margin: 8px 0 0; background: var(--surface);
  border: 1px solid var(--line); border-radius: var(--radius); box-shadow: var(--shadow-1);
}
.question-prompt .hint { display: block; font-size: 0.9rem; font-weight: 400; color: var(--ink-2); margin-top: 8px; }

.options { display: grid; gap: 10px; grid-template-columns: repeat(auto-fit, minmax(230px, 1fr)); }
.option {
  display: flex; align-items: center; gap: 11px; text-align: left;
  padding: 14px 16px; font: inherit; font-size: 0.99rem;
  background: var(--surface); color: var(--ink);
  border: 1px solid var(--line-strong); border-radius: var(--radius-sm); cursor: pointer;
  transition: border-color 0.12s, background 0.12s;
}
.option:hover:not(:disabled) { border-color: var(--accent); background: var(--accent-soft); }
.option:disabled { cursor: default; }
.option:disabled:not([data-state]) { opacity: 0.5; }
.option .key {
  flex: 0 0 auto; width: 24px; height: 24px; border-radius: 6px;
  display: grid; place-items: center; background: var(--surface-2);
  font-size: 0.78rem; font-weight: 650; color: var(--ink-2);
}
.option[data-state="correct"] { border-color: var(--good); background: color-mix(in srgb, var(--good) 12%, var(--surface)); }
.option[data-state="wrong"] { border-color: var(--critical); background: color-mix(in srgb, var(--critical) 12%, var(--surface)); }
/* White on this green would only reach 3.35:1; dark ink reaches 5.87:1. */
.option[data-state="correct"] .key { background: var(--good); color: #0b0b0b; }
.option[data-state="wrong"] .key { background: var(--critical); color: #fff; }

.answer-form { display: flex; gap: 10px; align-items: flex-start; flex-wrap: wrap; }
.answer-form .input { flex: 1 1 240px; font-size: 1.05rem; padding: 13px 14px; }

.banner {
  display: flex; gap: 11px; align-items: flex-start;
  padding: 13px 16px; border-radius: var(--radius-sm); margin-top: 16px;
  border: 1px solid var(--line-strong); background: var(--surface-2);
}
.banner svg { width: 20px; height: 20px; flex: 0 0 auto; margin-top: 1px; }
.banner strong { display: block; }
.banner-good { border-color: var(--good); color: var(--good-ink); background: color-mix(in srgb, var(--good) 10%, var(--surface)); }
.banner-bad { border-color: var(--critical); color: var(--critical-ink); background: color-mix(in srgb, var(--critical) 10%, var(--surface)); }
.banner-warn { border-color: var(--warning); color: var(--ink); background: color-mix(in srgb, var(--warning) 16%, var(--surface)); }
.banner-body { min-width: 0; color: var(--ink); }
.banner-good .banner-title { color: var(--good-ink); }
.banner-bad .banner-title { color: var(--critical-ink); }
.banner-title { font-weight: 650; }

/* Match game */

.match-grid { display: grid; gap: 10px; grid-template-columns: repeat(auto-fit, minmax(150px, 1fr)); }
.match-tile {
  display: flex; align-items: center; justify-content: center; text-align: center;
  min-height: 92px; padding: 12px; font: inherit; font-size: 0.95rem;
  background: var(--surface); color: var(--ink);
  border: 1px solid var(--line-strong); border-radius: var(--radius-sm); cursor: pointer;
  transition: border-color 0.12s, background 0.12s, opacity 0.25s, transform 0.12s;
}
.match-tile:hover:not(:disabled) { border-color: var(--accent); transform: translateY(-2px); }
.match-tile[data-state="picked"] { border-color: var(--accent); background: var(--accent-soft); border-width: 2px; }
.match-tile[data-state="hit"] { opacity: 0; pointer-events: none; }
.match-tile[data-state="miss"] { border-color: var(--critical); background: color-mix(in srgb, var(--critical) 12%, var(--surface)); }
.match-timer { font-size: 1.6rem; font-weight: 680; font-variant-numeric: tabular-nums; letter-spacing: -0.02em; }

/* Summary */

.summary { text-align: center; padding: 8px 0 0; }
.summary-score { font-size: clamp(2.6rem, 2rem + 3vw, 3.6rem); font-weight: 700; letter-spacing: -0.03em; line-height: 1; }
.summary-label { color: var(--ink-2); margin-bottom: 20px; }
.summary-actions { display: flex; gap: 10px; justify-content: center; flex-wrap: wrap; margin: 22px 0; }
.summary-list { text-align: left; }

/* Charts */

.chart-figure { margin: 0; }
.chart-title { font-size: 0.95rem; font-weight: 650; margin: 0 0 2px; }
.chart-sub { font-size: 0.84rem; color: var(--ink-muted); margin: 0 0 14px; }
.legend { display: flex; gap: 14px; flex-wrap: wrap; margin-top: 12px; font-size: 0.84rem; color: var(--ink-2); }
.legend-item { display: inline-flex; align-items: center; gap: 6px; }
.legend-swatch { width: 11px; height: 11px; border-radius: 3px; flex: 0 0 auto; }
.chart-tooltip {
  position: fixed; z-index: 45; pointer-events: none;
  background: var(--ink); color: var(--page);
  padding: 6px 10px; border-radius: 7px; font-size: 0.82rem; font-weight: 550;
  box-shadow: var(--shadow-2); opacity: 0; transition: opacity 0.1s;
  white-space: nowrap;
}
.chart-tooltip[data-show="1"] { opacity: 1; }

details.table-view { margin-top: 14px; }
details.table-view summary { cursor: pointer; font-size: 0.86rem; color: var(--ink-2); font-weight: 600; }
details.table-view summary:hover { color: var(--ink); }
details.table-view > div { margin-top: 10px; }

/* Keyboard shortcut list */

.kbd-list { display: grid; gap: 8px; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); }
.kbd-row { display: flex; align-items: baseline; gap: 10px; justify-content: space-between; padding: 7px 0; border-bottom: 1px solid var(--line); }
kbd {
  font: inherit; font-size: 0.78rem; font-weight: 650;
  padding: 2px 7px; border-radius: 5px; background: var(--surface-2);
  border: 1px solid var(--line-strong); color: var(--ink-2); white-space: nowrap;
}

/* Responsive */

@media (max-width: 720px) {
  .topbar-inner { flex-wrap: wrap; gap: 10px; }
  .topnav { order: 3; width: 100%; overflow-x: auto; }
  .brand { flex: 1 1 auto; }
  .card-row { grid-template-columns: 1fr auto; }
  .editor-row { grid-template-columns: 1fr auto; }
  .editor-row .idx { display: none; }
  .hero { gap: 18px; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation-duration: 0.01ms !important; transition-duration: 0.01ms !important; }
  .flashcard-inner { transition: none; }
}

/* Print: a foldable revision sheet, terms on the left, answers on the right. */

@media print {
  .topbar, .footer, .skip-link, .toast, .study-toolbar, .sticky-actions,
  .btn, .icon-btn, .mode-grid, .search-bar, .chart-tooltip,
  .card-row-tools, .meter, .set-card-meta { display: none !important; }
  body { background: #fff; color: #000; }
  .container { max-width: none; padding: 0; }
  .panel, .card-row { border: 1px solid #999; box-shadow: none; }
  /* A flex container ignores column-count, so the sheet has to be a block. */
  .print-sheet { display: block; column-count: 2; column-gap: 24px; }
  .print-sheet .card-row {
    display: grid; grid-template-columns: 1fr 1fr; gap: 12px;
    break-inside: avoid; margin-bottom: 8px;
  }
  a[href^="#"]::after { content: ""; }
}

/* Chart marks: bars capped at 24px, 4px rounded data ends, 2px gaps in the
   surface colour doing the separating. */

.mastery-bar {
  display: flex; gap: 2px; height: 22px; border-radius: 4px;
  overflow: hidden; background: var(--surface);
}
.mastery-seg { min-width: 3px; cursor: default; }
.mastery-seg:focus-visible { outline: 2px solid var(--ink); outline-offset: 1px; }
.mastery-empty { flex: 1 1 auto; background: var(--viz-empty); }

.chart-plot { position: relative; padding-top: 14px; }
.chart-gridtop {
  position: absolute; left: 0; right: 0; top: 14px;
  border-top: 1px solid var(--viz-grid);
}
.chart-axis-label {
  position: absolute; right: 0; top: -15px;
  font-size: 0.72rem; color: var(--ink-muted); font-variant-numeric: tabular-nums;
}
.chart-columns {
  display: flex; align-items: flex-end; gap: 4px;
  height: 118px; border-bottom: 1px solid var(--viz-axis);
}
.chart-col {
  flex: 1 1 0; min-width: 0; height: 100%;
  display: flex; align-items: flex-end; justify-content: center; cursor: default;
}
.chart-col:focus-visible { outline: 2px solid var(--ink); outline-offset: 2px; }
.chart-col-fill {
  width: 100%; max-width: 24px; min-height: 2px;
  background: var(--viz-series); border-radius: 4px 4px 0 0;
}
.chart-col-fill[data-empty="1"] { background: var(--viz-empty); border-radius: 2px; }
.chart-xaxis {
  display: flex; justify-content: space-between;
  margin-top: 6px; font-size: 0.76rem; color: var(--ink-muted);
}