/* CogPrep Arcade base styles. Light and dark themes follow prefers-color-scheme. */

:root {
  --bg: #f6f5f1;
  --fg: #1b1c20;
  --muted: #565863;
  --card: #ffffff;
  --line: #d6d5d0;
  --accent: #0057b8;
  --accent-fg: #ffffff;
  --focus: #0057b8;
  --ok: #1d7a4f;
  --warn: #a4400b;
  --mid: #7a5d00;
  --board: #d9d6cc;
  --cell: #f2f0ea;
  --wall: #34353a;
  --wall-hatch: rgba(255, 255, 255, 0.18);
  --exit: #1d7a4f;
  --ball: #f0e442;
  --ball-ring: #1b1c20;
  --piece-edge: rgba(0, 0, 0, 0.55);
  --radius: 10px;
  --shadow: 0 1px 2px rgba(0, 0, 0, 0.08), 0 2px 8px rgba(0, 0, 0, 0.05);
  /* Chart series (validated categorical slots 1 to 3) and chrome. */
  --series-1: #2a78d6;
  --series-2: #eb6834;
  --series-3: #1baf7a;
  --viz-grid: #e1e0d9;
  --viz-axis: #c3c2b7;
  color-scheme: light dark;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #121317;
    --fg: #ececf1;
    --muted: #a7a9b4;
    --card: #1c1d23;
    --line: #34363f;
    --accent: #6cb2ff;
    --accent-fg: #0b1220;
    --focus: #8cc4ff;
    --ok: #5fd39a;
    --warn: #ff9a62;
    --mid: #e9c75a;
    --board: #2a2c34;
    --cell: #1f2127;
    --wall: #050506;
    --wall-hatch: rgba(255, 255, 255, 0.22);
    --exit: #5fd39a;
    --ball-ring: #050506;
    --piece-edge: rgba(0, 0, 0, 0.75);
    --shadow: 0 1px 2px rgba(0, 0, 0, 0.5);
    --series-1: #3987e5;
    --series-2: #d95926;
    --series-3: #199e70;
    --viz-grid: #2c2c2a;
    --viz-axis: #383835;
  }
}


:root[data-theme="dark"] {
  --bg: #121317;
  --fg: #ececf1;
  --muted: #a7a9b4;
  --card: #1c1d23;
  --line: #34363f;
  --accent: #6cb2ff;
  --accent-fg: #0b1220;
  --focus: #8cc4ff;
  --ok: #5fd39a;
  --warn: #ff9a62;
  --mid: #e9c75a;
  --board: #2a2c34;
  --cell: #1f2127;
  --wall: #050506;
  --wall-hatch: rgba(255, 255, 255, 0.22);
  --exit: #5fd39a;
  --ball-ring: #050506;
  --piece-edge: rgba(0, 0, 0, 0.75);
  --shadow: 0 1px 2px rgba(0, 0, 0, 0.5);
  --series-1: #3987e5;
  --series-2: #d95926;
  --series-3: #199e70;
  --viz-grid: #2c2c2a;
  --viz-axis: #383835;
}

:root[data-theme="light"] {
  --bg: #f6f5f1;
  --fg: #1b1c20;
  --muted: #565863;
  --card: #ffffff;
  --line: #d6d5d0;
  --accent: #0057b8;
  --accent-fg: #ffffff;
  --focus: #0057b8;
  --ok: #1d7a4f;
  --warn: #a4400b;
  --mid: #7a5d00;
  --board: #d9d6cc;
  --cell: #f2f0ea;
  --wall: #34353a;
  --wall-hatch: rgba(255, 255, 255, 0.18);
  --exit: #1d7a4f;
  --ball: #f0e442;
  --ball-ring: #1b1c20;
  --piece-edge: rgba(0, 0, 0, 0.55);
  --shadow: 0 1px 2px rgba(0, 0, 0, 0.08), 0 2px 8px rgba(0, 0, 0, 0.05);
  --series-1: #2a78d6;
  --series-2: #eb6834;
  --series-3: #1baf7a;
  --viz-grid: #e1e0d9;
  --viz-axis: #c3c2b7;
}

* { box-sizing: border-box; }

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

body {
  margin: 0;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  background: var(--bg);
  color: var(--fg);
  font: 16px/1.5 system-ui, -apple-system, "Segoe UI", Roboto, Ubuntu, sans-serif;
}

a { color: var(--accent); }

:focus-visible {
  outline: 3px solid var(--focus);
  outline-offset: 2px;
}

.sr-only {
  position: absolute !important;
  width: 1px; height: 1px;
  padding: 0; margin: -1px;
  overflow: hidden; clip: rect(0 0 0 0);
  white-space: nowrap; border: 0;
}

.skip-link {
  position: absolute; left: 8px; top: -48px;
  background: var(--card); color: var(--fg);
  padding: 8px 12px; border-radius: 6px; z-index: 10;
}
.skip-link:focus { top: 8px; }

/* ------------------------------------------------ header and footer */

.site-header {
  display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between;
  gap: 8px 24px;
  padding: 12px clamp(16px, 4vw, 40px);
  border-bottom: 1px solid var(--line);
  background: var(--card);
}
.brand {
  display: inline-flex; align-items: center; gap: 10px;
  font-weight: 700; font-size: 1.1rem; color: var(--fg); text-decoration: none;
}
.brand-mark {
  width: 22px; height: 22px; border-radius: 5px; background: #0072b2; position: relative;
}
.brand-mark::after {
  content: ""; position: absolute; inset: 5px; border-radius: 50%;
  background: var(--ball); border: 2px solid #1b1c20;
}
.site-header nav { display: flex; gap: 4px; flex-wrap: wrap; }
.site-header nav a {
  color: var(--fg); text-decoration: none; padding: 6px 10px; border-radius: 6px;
}
.site-header nav a:hover { background: var(--bg); }
.site-header nav a[aria-current] { background: var(--bg); font-weight: 600; }

.theme-toggle {
  background: transparent;
  color: var(--fg);
  border: 1px solid var(--line);
  padding: 4px 8px;
  border-radius: 6px;
  cursor: pointer;
  font-size: 0.85rem;
  margin-left: 4px;
  transition: background 0.15s ease;
}
.theme-toggle:hover { background: var(--bg); }


main {
  flex: 1;
  width: 100%;
  max-width: 1080px;
  margin: 0 auto;
  padding: 24px clamp(16px, 4vw, 40px) 48px;
}
main:focus { outline: none; }

.site-footer {
  border-top: 1px solid var(--line);
  background: var(--card);
  color: var(--muted);
  font-size: 0.875rem;
  padding: 16px clamp(16px, 4vw, 40px);
}
.site-footer p { max-width: 1080px; margin: 0 auto; }

/* ------------------------------------------------ generic pieces */

h1 { font-size: clamp(1.6rem, 3.5vw, 2.2rem); line-height: 1.2; margin: 0 0 8px; }
h2 { font-size: 1.25rem; margin: 0 0 8px; }
h3 { font-size: 1.1rem; margin: 16px 0 8px; }
.muted { color: var(--muted); }
.small { font-size: 0.875rem; }
.section-title { margin-top: 32px; }
.prose { max-width: 72ch; }
.notice, .callout {
  padding: 12px 16px; border-radius: var(--radius);
  border: 1px solid var(--line); background: var(--card);
  border-left: 5px solid var(--accent);
}
.callout-ok { border-left-color: var(--ok); }

.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 6px;
  min-height: 44px; padding: 8px 16px;
  border: 1px solid var(--line); border-radius: 8px;
  background: var(--card); color: var(--fg);
  font: inherit; font-weight: 600; text-decoration: none; cursor: pointer;
}
.btn:hover:not(:disabled) { border-color: var(--fg); }
.btn:disabled { opacity: 0.5; cursor: not-allowed; }
.btn-primary { background: var(--accent); color: var(--accent-fg); border-color: var(--accent); }
.btn-primary:hover:not(:disabled) { filter: brightness(1.08); border-color: var(--accent); }
.btn-warn { color: var(--warn); }
.btn-quiet { background: transparent; }
.btn-small { min-height: 36px; padding: 4px 10px; font-size: 0.9rem; }
.btn-big { font-size: 1.1rem; padding: 12px 24px; margin-top: 8px; }

.badge {
  display: inline-block; padding: 2px 10px; border-radius: 999px;
  font-size: 0.8rem; font-weight: 700; border: 1.5px solid currentColor; white-space: nowrap;
}
.badge-ok { color: var(--ok); }
.badge-soon { color: var(--muted); border-style: dashed; }
.badge-warn { color: var(--warn); }
.badge-mid { color: var(--mid); }

/* ------------------------------------------------ home */

.hero { padding: 0 0 8px; }
.hero h1 { margin-bottom: 4px; }
.hero-sub { margin: 0 0 12px; color: var(--muted); }
.btn-hero { display: flex; width: 100%; max-width: 420px; font-size: 1.1rem; min-height: 52px; }
.hero-hint { margin: 8px 0 0; }
.resume-row { display: flex; flex-wrap: wrap; gap: 4px 12px; align-items: center; margin: 8px 0 0; }
.resume-row a { display: inline-flex; align-items: center; min-height: 44px; }
.card-grid {
  list-style: none; padding: 0; margin: 16px 0 0;
  display: grid; gap: 12px;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
}
@media (max-width: 600px) { .card-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 10px; } }
.card-grid > li { display: flex; }
.game-card, .set-card {
  background: var(--card); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 16px; box-shadow: var(--shadow);
  display: flex; flex-direction: column; gap: 4px;
}
a.game-card { flex: 1; position: relative; min-height: 44px; padding: 12px; gap: 6px; color: var(--fg); text-decoration: none; align-items: flex-start; }
a.game-card:hover { border-color: var(--accent); }
a.game-card:focus-visible { outline: 3px solid var(--focus); outline-offset: 3px; }
.game-card.is-soon { flex: 1; padding: 12px; gap: 6px; align-items: flex-start; background: transparent; box-shadow: none; border-style: dashed; }
.card-name { font-weight: 800; font-size: 1.05rem; line-height: 1.2; padding-right: 14px; }
.badge-skill { color: var(--muted); white-space: normal; border-radius: 8px; border-width: 1px; font-size: 0.75rem; }
.status-dot { position: absolute; top: 12px; right: 10px; width: 10px; height: 10px; border-radius: 50%; }
.status-dot.is-progress { background: var(--mid); }
.status-dot.is-mastered { background: var(--ok); }
.due-chip { font-size: 0.8rem; font-weight: 700; color: var(--warn); }
.maker-line { margin: 16px 0 0; }
.card-head { display: flex; justify-content: space-between; align-items: baseline; gap: 8px; }
.card-head h3, .card-head h2 { margin: 0; }

/* ------------------------------------------------ block slide menu */

.page-head { margin-bottom: 16px; }
.crumbs { margin: 0 0 4px; color: var(--muted); font-size: 0.9rem; }
.mode-explainer {
  display: grid; gap: 16px; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  margin: 16px 0;
}
.mode-explainer > div {
  border: 1px solid var(--line); border-radius: var(--radius); padding: 12px 16px; background: var(--card);
}
.mode-explainer p { margin: 0; color: var(--muted); }
.toolbar { display: flex; flex-wrap: wrap; gap: 12px; align-items: center; justify-content: space-between; margin: 8px 0 16px; }
.toggle { display: inline-flex; align-items: center; gap: 8px; font-weight: 600; cursor: pointer; }
.toggle input { width: 20px; height: 20px; }
.set-list { list-style: none; padding: 0; margin: 0; display: grid; gap: 16px; }
.set-card.is-locked { opacity: 0.8; box-shadow: none; }
.set-meta, .set-progress { margin: 0; }
.set-progress { color: var(--muted); font-size: 0.9rem; }
.set-actions { display: flex; flex-wrap: wrap; gap: 12px; align-items: center; justify-content: space-between; margin-top: 8px; }
.chips { display: flex; flex-wrap: wrap; gap: 6px; }
.chip {
  display: inline-flex; align-items: center; justify-content: center;
  min-width: 40px; height: 40px; border-radius: 8px;
  border: 1.5px solid var(--line); color: var(--fg); text-decoration: none; font-weight: 700;
  background: var(--bg);
}
.chip:hover { border-color: var(--fg); }
.chip-done { border-color: var(--mid); border-width: 2.5px; }
.chip-perfect { border-color: var(--ok); border-width: 2.5px; }
.chip-perfect::after { content: "\2713"; font-size: 0.7rem; margin-left: 2px; color: var(--ok); }
.chip-locked { opacity: 0.4; }

/* ------------------------------------------------ play area */

.play-area {
  display: grid; gap: 24px;
  grid-template-columns: minmax(0, 540px) minmax(220px, 1fr);
  align-items: start;
}
@media (max-width: 760px) {
  .play-area { grid-template-columns: 1fr; }
}
.board-col { display: flex; flex-direction: column; align-items: center; gap: 12px; width: 100%; }
.side-col { display: flex; flex-direction: column; gap: 12px; }
.stats { display: flex; flex-wrap: wrap; gap: 8px 20px; font-size: 1.05rem; }
.stat-value { font-size: 1.4rem; margin-left: 4px; }
.controls { display: flex; flex-wrap: wrap; gap: 8px; }
.play-message { min-height: 1.5em; margin: 0; font-weight: 600; }
.help summary, .strategy summary { cursor: pointer; font-weight: 600; }
.help ul { padding-left: 20px; margin: 8px 0 0; color: var(--muted); }

/* Board: square grid; pieces absolutely positioned by --r/--c/--w/--h. */
.board-wrap {
  --exit-space: 30px;
  padding: var(--exit-space);
  width: 100%;
  max-width: 540px;
}
.board-wrap.is-small { max-width: 360px; --exit-space: 24px; }
.board {
  --gap: 3px;
  position: relative;
  width: 100%;
  aspect-ratio: 1 / 1;
  background: var(--board);
  border-radius: 8px;
  border: 2px solid var(--line);
  touch-action: manipulation;
  user-select: none;
  -webkit-user-select: none;
}
.cell, .piece, .exit-marker { position: absolute; }
.cell {
  left: calc(var(--c) * 100% / var(--n) + var(--gap));
  top: calc(var(--r) * 100% / var(--n) + var(--gap));
  width: calc(100% / var(--n) - 2 * var(--gap));
  height: calc(100% / var(--n) - 2 * var(--gap));
  background: var(--cell);
  border-radius: 5px;
}
.cell.wall {
  background-color: var(--wall);
  background-image: repeating-linear-gradient(45deg, var(--wall-hatch) 0 3px, transparent 3px 8px),
    repeating-linear-gradient(-45deg, var(--wall-hatch) 0 3px, transparent 3px 8px);
}
.cell.exit-cell {
  background: color-mix(in srgb, var(--exit) 18%, var(--cell));
  outline: 3px dashed var(--exit);
  outline-offset: -3px;
}
.exit-marker {
  display: flex; align-items: center; justify-content: center; gap: 2px;
  color: var(--exit); font-weight: 800; font-size: 0.7rem; letter-spacing: 0.04em;
  pointer-events: none;
}
.exit-arrow { font-size: 1.1rem; line-height: 1; }
.exit-marker.side-top, .exit-marker.side-bottom {
  flex-direction: column;
  left: calc(var(--c) * 100% / var(--n));
  width: calc(100% / var(--n));
  height: var(--exit-space);
}
.exit-marker.side-top { bottom: 100%; flex-direction: column-reverse; }
.exit-marker.side-bottom { top: 100%; }
.exit-marker.side-left, .exit-marker.side-right {
  top: calc(var(--r) * 100% / var(--n));
  height: calc(100% / var(--n));
  width: var(--exit-space);
  flex-direction: column;
}
.exit-marker.side-left { right: 100%; }
.exit-marker.side-right { left: 100%; }
.exit-marker.side-left .exit-text, .exit-marker.side-right .exit-text { writing-mode: vertical-rl; }

.piece {
  left: calc(var(--c) * 100% / var(--n) + var(--gap));
  top: calc(var(--r) * 100% / var(--n) + var(--gap));
  width: calc(var(--w) * 100% / var(--n) - 2 * var(--gap));
  height: calc(var(--h) * 100% / var(--n) - 2 * var(--gap));
  margin: 0; padding: 0; font: inherit;
  display: flex; align-items: center; justify-content: center;
  transition: left 140ms ease, top 140ms ease, box-shadow 120ms ease, transform 120ms ease;
  cursor: pointer;
}
div.piece { cursor: default; }
.block {
  border-radius: 7px;
  border: 2px solid var(--piece-edge);
  background-color: var(--pc);
  color: #111;
}
.ball {
  border-radius: 50%;
  border: 3px solid var(--ball-ring);
  background: radial-gradient(circle at 50% 50%, var(--ball-ring) 0 14%, var(--ball) 15% 100%);
  transform: scale(0.84);
  z-index: 2;
}
.piece-label {
  display: inline-flex; align-items: center; justify-content: center;
  min-width: 1.6em; height: 1.6em; padding: 0 0.3em;
  border-radius: 999px; background: #fff; color: #111;
  font-weight: 800; font-size: clamp(0.7rem, 2.6vw, 1rem); border: 1.5px solid #111;
}
.ball .piece-label { display: none; }
.is-small .piece-label { font-size: 0.7rem; }

/* Block patterns: a second cue besides colour. */
.pat-diag { background-image: repeating-linear-gradient(45deg, rgba(255, 255, 255, 0.45) 0 4px, transparent 4px 10px); }
.pat-rdiag { background-image: repeating-linear-gradient(-45deg, rgba(0, 0, 0, 0.35) 0 4px, transparent 4px 10px); }
.pat-dots { background-image: radial-gradient(rgba(0, 0, 0, 0.4) 22%, transparent 24%); background-size: 11px 11px; }
.pat-grid { background-image: linear-gradient(rgba(255, 255, 255, 0.5) 2px, transparent 2px), linear-gradient(90deg, rgba(255, 255, 255, 0.5) 2px, transparent 2px); background-size: 10px 10px; }
.pat-hlines { background-image: repeating-linear-gradient(0deg, rgba(255, 255, 255, 0.5) 0 3px, transparent 3px 9px); }
.pat-vlines { background-image: repeating-linear-gradient(90deg, rgba(0, 0, 0, 0.3) 0 3px, transparent 3px 9px); }
.pat-checks { background-image: conic-gradient(rgba(255, 255, 255, 0.35) 25%, transparent 0 50%, rgba(255, 255, 255, 0.35) 0 75%, transparent 0); background-size: 14px 14px; }
.pat-solid { background-image: none; }

.piece.is-selected {
  box-shadow: 0 0 0 3px var(--bg), 0 0 0 6px var(--focus);
  z-index: 3;
}
.ball.is-selected { transform: scale(0.9); }
.piece.is-hint, .piece.is-moved { box-shadow: 0 0 0 3px var(--bg), 0 0 0 6px var(--ok); z-index: 3; }
.move-badge:empty { display: none; }
.move-badge {
  position: absolute; top: -10px; right: -10px;
  width: 24px; height: 24px; border-radius: 50%;
  display: flex; align-items: center; justify-content: center;
  background: var(--ok); color: var(--bg); font-weight: 800; font-size: 0.95rem;
  border: 2px solid var(--bg);
}
.piece.is-blocked { animation: nudge 220ms ease; }
@keyframes nudge {
  25% { translate: -4px 0; }
  75% { translate: 4px 0; }
}

.arrow-pad {
  display: grid; gap: 6px;
  grid-template-columns: repeat(3, 56px);
  grid-template-areas: ". up ." "left down right";
}
.pad-btn {
  width: 56px; height: 56px; border-radius: 12px;
  border: 1.5px solid var(--line); background: var(--card); color: var(--fg);
  font-size: 1.5rem; font-weight: 800; cursor: pointer;
}
.pad-btn:hover:not(.is-off) { border-color: var(--fg); }
.pad-btn.is-off { opacity: 0.35; cursor: not-allowed; }
.pad-U { grid-area: up; }
.pad-D { grid-area: down; }
.pad-L { grid-area: left; }
.pad-R { grid-area: right; }

/* ------------------------------------------------ results and replay */

.after { margin-top: 24px; }
.after-actions { display: flex; flex-wrap: wrap; gap: 8px; margin: 16px 0; }
.explain {
  border: 1px solid var(--line); border-radius: var(--radius); background: var(--card);
  padding: 16px; box-shadow: var(--shadow);
}
.result-line { display: flex; align-items: center; gap: 12px; flex-wrap: wrap; }
.result-line p { margin: 0; font-weight: 600; font-size: 1.05rem; }
.explain-body {
  display: grid; gap: 16px; grid-template-columns: minmax(0, 360px) minmax(0, 1fr); align-items: start;
}
@media (max-width: 760px) {
  .explain-body { grid-template-columns: 1fr; }
}
.explain-board { display: flex; flex-direction: column; align-items: center; gap: 8px; width: 100%; }
.replay-controls { display: flex; gap: 6px; flex-wrap: wrap; justify-content: center; }
.step-counter { color: var(--muted); font-size: 0.9rem; }
.step-reason {
  margin: 0 0 8px; padding: 10px 12px; min-height: 3em;
  border-left: 4px solid var(--ok); background: var(--bg); border-radius: 6px; font-weight: 600;
}
.step-list { margin: 0; padding-left: 0; list-style: none; counter-reset: step; }
.step-list li { counter-increment: step; }
.step-link {
  display: block; width: 100%; text-align: left;
  font: inherit; color: var(--fg); background: none; border: 0; border-radius: 6px;
  padding: 6px 8px; cursor: pointer;
}
.step-link::before { content: counter(step) ". "; font-weight: 700; }
.step-link:hover { background: var(--bg); }
.step-list li[aria-current] .step-link { background: color-mix(in srgb, var(--ok) 18%, transparent); font-weight: 600; }
.strategy { margin-top: 16px; }
.strategy ul { padding-left: 20px; margin: 8px 0 0; }

/* ------------------------------------------------ timed run */

.run-intro ul { padding-left: 20px; }
.run-bar {
  display: flex; flex-wrap: wrap; align-items: center; gap: 8px 24px;
  padding: 10px 16px; margin-bottom: 8px;
  border: 1px solid var(--line); border-radius: var(--radius); background: var(--card);
  position: sticky; top: 0; z-index: 5;
}
.clock { font-variant-numeric: tabular-nums; font-size: 1.6rem; font-weight: 800; }
.clock.is-low { color: var(--warn); }
.run-progress, .run-score { font-weight: 600; }
.flash { min-height: 1.5em; margin: 0 0 8px; color: var(--ok); font-weight: 600; }
.score-tiles { display: grid; gap: 12px; grid-template-columns: repeat(auto-fit, minmax(170px, 1fr)); margin: 12px 0; }
.tile {
  border: 1px solid var(--line); border-radius: var(--radius); background: var(--card);
  padding: 12px 16px; display: flex; flex-direction: column;
}
.tile-label { color: var(--muted); font-size: 0.85rem; }
.tile strong { font-size: 1.5rem; }
.table-wrap { overflow-x: auto; }
.results, .dvs-table { border-collapse: collapse; width: 100%; background: var(--card); border-radius: var(--radius); }
.results th, .results td, .dvs-table th, .dvs-table td { padding: 8px 10px; border-bottom: 1px solid var(--line); text-align: left; }
.results th, .dvs-table th { font-size: 0.85rem; color: var(--muted); }
.review-host { margin-top: 16px; }

/* ------------------------------------------------ exam mode */

.exam-active .site-header nav { visibility: hidden; }
.run-intro { max-width: 820px; }
.exam-rules { padding-left: 22px; }
.exam-rules li { margin-bottom: 6px; }
.exam-hud {
  display: flex; flex-wrap: wrap; align-items: center; justify-content: center; gap: 8px 28px;
  padding: 10px 16px; margin: 0 auto 8px; max-width: 600px;
  border: 1px solid var(--line); border-radius: var(--radius); background: var(--card);
  position: sticky; top: 0; z-index: 5;
}
.exam-hud.is-tutorial { position: static; }
.hud-slot { display: inline-flex; align-items: center; gap: 8px 24px; flex-wrap: wrap; }
.hud-slot .stats { font-size: 1rem; }
.hud-slot .stat-value { font-size: 1.25rem; }
.play-area.is-exam { display: flex; justify-content: center; }
.play-area.is-exam .board-col { max-width: 540px; }
.flash { text-align: center; }

/* ------------------------------------------------ coach */

.coach {
  border: 1px solid var(--line); border-radius: var(--radius); background: var(--card);
  padding: 4px 16px 12px; margin: 16px 0; box-shadow: var(--shadow);
}
.metric-strip { display: flex; flex-wrap: wrap; gap: 8px 24px; margin: 0 0 8px; }
.metric-strip div { display: flex; flex-direction: column; }
.metric-strip dt { color: var(--muted); font-size: 0.8rem; }
.metric-strip dd { margin: 0; font-weight: 700; font-variant-numeric: tabular-nums; }
.findings { list-style: none; padding: 0; margin: 0; display: grid; gap: 10px; }
.finding { display: grid; grid-template-columns: 4.2rem 1fr; gap: 10px; align-items: start; padding: 8px 0; border-top: 1px solid var(--line); }
.finding:first-child { border-top: 0; }
.finding .badge { justify-self: start; margin-top: 2px; }
.finding p { margin: 0 0 2px; }
.finding-detail { color: var(--fg); }
.finding-tip { color: var(--muted); }
.habits { padding-left: 22px; }
.habits li { margin-bottom: 6px; }
.callout-warn { border-left-color: var(--warn); }
.callout-sample { border-left-color: var(--mid); }
.badge-sample { color: var(--mid); border-style: double; border-width: 3px; }

/* ------------------------------------------------ analytics */

.filter { font-weight: 600; display: inline-flex; gap: 8px; align-items: center; }
.filter select { font: inherit; min-height: 40px; padding: 4px 8px; border-radius: 8px; border: 1px solid var(--line); background: var(--card); color: var(--fg); }
.summary ul { margin: 0; padding-left: 20px; }
.summary h2 { margin-top: 4px; }
.viz-board { display: grid; gap: 16px; grid-template-columns: repeat(auto-fit, minmax(min(100%, 440px), 1fr)); }
.viz {
  margin: 0; padding: 12px 16px; border: 1px solid var(--line); border-radius: var(--radius);
  background: var(--card); display: flex; flex-direction: column; gap: 6px;
}
.viz figcaption { display: flex; flex-direction: column; }
.viz-title { font-weight: 700; }
.viz-sub { color: var(--muted); font-size: 0.85rem; }
.viz-plot { position: relative; }
.viz-svg { width: 100%; height: auto; display: block; overflow: visible; }
.viz-svg:focus-visible { outline: 3px solid var(--focus); }
.viz-svg .viz-grid { stroke: var(--viz-grid); stroke-width: 1; }
.viz-svg .viz-axis { stroke: var(--viz-axis); stroke-width: 1; }
.viz-svg .viz-tick { fill: var(--muted); font-size: 12px; font-variant-numeric: tabular-nums; }
.viz-svg .viz-value { fill: var(--fg); font-size: 12px; font-weight: 600; }
.viz-svg .viz-line { fill: none; stroke-width: 2; stroke-linejoin: round; stroke-linecap: round; }
.viz-svg .viz-dot, .viz-svg .viz-hot { stroke: var(--card); stroke-width: 2; }
.viz-svg .viz-cross { stroke: var(--viz-axis); stroke-width: 1; }
.viz-svg .viz-jump-ring { fill: none; stroke: var(--fg); stroke-width: 1.5; }
.viz-svg .viz-jump-label { fill: var(--fg); font-size: 12px; font-weight: 700; }
.viz-svg .viz-bar:focus-visible { outline: none; stroke: var(--focus); stroke-width: 2; }
.viz-legend { list-style: none; display: flex; flex-wrap: wrap; gap: 4px 16px; margin: 0; padding: 0; font-size: 0.85rem; color: var(--muted); }
.viz-legend li { display: inline-flex; align-items: center; gap: 6px; }
.viz-key { display: inline-block; background: var(--key); flex: none; }
.viz-key-line { width: 16px; height: 3px; border-radius: 2px; }
.viz-key-dot { width: 9px; height: 9px; border-radius: 50%; }
.viz-tip {
  position: absolute; top: 4px; min-width: 150px; max-width: 260px; pointer-events: none;
  display: flex; flex-direction: column; gap: 2px; padding: 8px 10px; font-size: 0.85rem;
  background: var(--card); color: var(--fg); border: 1px solid var(--line); border-radius: 8px; box-shadow: var(--shadow);
}
.viz-tip[hidden] { display: none; }
.viz-tip span { display: inline-flex; align-items: center; gap: 6px; }
.viz-tip-flag { font-weight: 700; }
.viz-table summary { cursor: pointer; color: var(--muted); font-size: 0.85rem; }
.viz-table .results td, .viz-table .results th { font-variant-numeric: tabular-nums; }
.backup { margin-top: 8px; }

@media (prefers-reduced-motion: reduce) {
  .piece { transition: none; }
  .piece.is-blocked { animation: none; }
  html:focus-within { scroll-behavior: auto; }
}

.maker-foot { margin-top: .5rem; }
.maker-nudge { display: flex; align-items: center; gap: 8px; margin: 16px 0 0; font-size: 0.9rem; }
.maker-nudge a { display: inline-flex; align-items: center; min-height: 44px; }
.maker-nudge-close { min-width: 44px; min-height: 44px; border: 0; background: transparent; color: var(--muted); font: inherit; font-size: 1.2rem; cursor: pointer; }
.maker-card { justify-content: space-between; padding: 4px 4px 4px 14px; border: 1px solid var(--line); border-radius: 8px; max-width: 520px; }
.maker-about { padding: 4px 14px; border: 1px solid var(--line); border-radius: 8px; max-width: 520px; }
.maker-links { margin: 0 0 12px; padding-left: 18px; }
.study-done { margin: 20px 0 0; font-weight: 600; }

/* ------------------------------------------------ onboarding and plain-language UX */

/* Visible active page: underline bar plus weight, not just a faint background. */
.site-header nav a { min-height: 44px; display: inline-flex; align-items: center; }
.site-header nav a[aria-current] { color: var(--accent); box-shadow: inset 0 -3px 0 var(--accent); border-radius: 6px 6px 0 0; }
.theme-toggle { min-height: 44px; padding: 4px 12px; }

/* 44px touch targets for every small control. */
.chip { min-width: 44px; height: 44px; }
.btn-small { min-height: 44px; }
.tier-chip, .tier-chip-small, .tag-chip { min-height: 44px; }
.toggle { min-height: 44px; }
.toggle input { width: 22px; height: 22px; accent-color: var(--accent); }
summary { min-height: 44px; display: list-item; padding: 10px 0; cursor: pointer; }
select, input[type="text"], input[type="search"], input:not([type]) {
  font: inherit; min-height: 44px; padding: 6px 10px; border-radius: 8px;
  border: 1px solid var(--line); background: var(--card); color: var(--fg);
}
.btn:focus-visible, .mode-card:focus-visible, .chip:focus-visible { outline: 3px solid var(--focus); outline-offset: 3px; }
.btn-outline { background: var(--card); color: var(--accent); border: 2px solid var(--accent); }
.btn-outline:hover:not(:disabled) { background: color-mix(in srgb, var(--accent) 10%, var(--card)); filter: none; }

/* Game start: the mode cards (practice, ranked timed test, fresh timed practice). */
.game-start .page-head { margin-bottom: 8px; }
.mode-choose .section-title { margin-top: 8px; }
.mode-cards { display: grid; gap: 16px; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); margin: 8px 0 12px; }
.mode-card {
  position: relative; display: flex; flex-direction: column; gap: 6px;
  padding: 20px; min-height: 180px; border-radius: var(--radius);
  background: var(--card); color: var(--fg); text-decoration: none;
  border: 2px solid var(--line); box-shadow: var(--shadow);
  transition: border-color 0.15s ease, transform 0.15s ease;
}
.mode-card:hover { border-color: var(--accent); transform: translateY(-1px); }
.mode-practice { border-color: var(--accent); }
.mode-title { font-size: 1.5rem; font-weight: 800; line-height: 1.2; }
.mode-sub { font-weight: 700; color: var(--accent); }
.mode-body { color: var(--muted); }
.mode-cta {
  margin-top: auto; align-self: flex-start; display: inline-flex; align-items: center; min-height: 44px;
  padding: 8px 16px; border-radius: 8px; font-weight: 700;
  background: var(--accent); color: var(--accent-fg);
}
.mode-timed .mode-cta, .mode-fresh .mode-cta { background: var(--card); color: var(--accent); border: 2px solid var(--accent); }
.mode-fresh { border-style: dashed; }
.run-mode { margin: 0 0 12px; }
.badge-start { position: absolute; top: 12px; right: 12px; color: var(--accent-fg); background: var(--ok); border-color: var(--ok); }
.mode-more { display: flex; flex-wrap: wrap; gap: 8px; }
.how-to-play { margin: 16px 0; padding: 0 16px; border: 1px solid var(--line); border-radius: var(--radius); background: var(--card); }
.how-to-play > summary { font-weight: 700; font-size: 1.1rem; }
.how-body { padding-bottom: 12px; }
.how-body h3 { margin-top: 12px; }
.set-buttons { display: flex; flex-wrap: wrap; gap: 8px; width: 100%; }
.chips-label { width: 100%; margin: 4px 0 0; }
.set-card.is-locked { opacity: 1; background: transparent; border-style: dashed; }
.locked-hint { margin: 8px 0 0; }

/* One-time coach marks. */
.coach-mark { margin: 0 0 16px; border-left-color: var(--ok); }
.coach-title { font-size: 1.1rem; margin: 0 0 4px; }
.coach-mark ul { margin: 0 0 8px; padding-left: 20px; }
.coach-mark p { margin: 4px 0 0; }
.brand, .nav-chip a, .game-tabs a { min-height: 44px; }
.game-tabs a { display: inline-flex; align-items: center; }
.filter select { min-height: 44px; }
/* leaderboard */
.lb-controls { display: flex; flex-wrap: wrap; gap: 10px 20px; margin: 12px 0 16px; align-items: center; }
.lb-tabs { display: flex; flex-wrap: wrap; gap: 6px; }
.lb-tab { padding: 6px 12px; border: 1px solid var(--line, #bbb); border-radius: 999px; background: transparent; color: inherit; font: inherit; cursor: pointer; }
.lb-tab.is-on { background: var(--accent, #2b6cb0); border-color: var(--accent, #2b6cb0); color: #fff; }
.lb-grid { display: grid; gap: 16px; grid-template-columns: repeat(auto-fit, minmax(min(100%, 430px), 1fr)); align-items: start; }
.lb-card { border: 1px solid var(--line, #ccc); border-radius: 12px; padding: 12px 14px; background: var(--card, transparent); }
.lb-head { display: flex; justify-content: space-between; align-items: baseline; gap: 8px; flex-wrap: wrap; }
.lb-head h2 { margin: 0 0 6px; font-size: 1.1rem; }
.lb-scroll { overflow-x: auto; }
.lb-table { width: 100%; border-collapse: collapse; font-size: .92rem; }
.lb-table th, .lb-table td { padding: 5px 6px; text-align: left; border-bottom: 1px solid var(--line, rgba(128,128,128,.25)); white-space: nowrap; }
.lb-table th { font-size: .78rem; text-transform: uppercase; letter-spacing: .03em; opacity: .7; }
.lb-table .lb-num { text-align: right; font-variant-numeric: tabular-nums; }
.lb-rank { width: 2.2em; }
.lb-score { font-weight: 700; }
.lb-table tr.is-me { background: rgba(43, 108, 176, .16); font-weight: 600; }
.lb-you { margin-left: 6px; padding: 1px 6px; border-radius: 6px; font-size: .7rem; background: var(--accent, #2b6cb0); color: #fff; }
.lb-foot { margin: 8px 0 0; font-size: .9rem; }
.lb-empty { margin: 8px 0; }
.lb-settings { margin-top: 20px; }
.lb-settings summary { cursor: pointer; font-weight: 600; }
@media (max-width: 520px) { .lb-hide { display: none; } }