:root {
  color-scheme: light;
  --paper: #f5f1e9;
  --paper-strong: #fffdf8;
  --ink: #252a25;
  --muted: #6b716a;
  --rule: #d8d6cb;
  --accent: #b54b35;
  --accent-dark: #8f3829;
  --board-light: #eee6d6;
  --board-dark: #9aaf9d;
  --board-shadow: #cad2c7;
  --good: #2c7358;
  --bad: #b54b35;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Arial, sans-serif;
  font-synthesis: none;
}

* { box-sizing: border-box; }
body { margin: 0; background: var(--paper); color: var(--ink); }
button, input { font: inherit; }
button { cursor: pointer; }
button:disabled { cursor: not-allowed; }
a { color: inherit; }
.app-shell { max-width: 1510px; min-height: 100svh; margin: auto; padding: 0 clamp(18px, 4.3vw, 72px); }

.topbar { min-height: 68px; display: flex; align-items: center; justify-content: space-between; gap: 20px; border-bottom: 1px solid var(--rule); }
.brand { display: flex; align-items: center; gap: 13px; }
.brand strong { display: block; font-size: 15px; letter-spacing: .105em; font-weight: 800; white-space: nowrap; }
.brand small { display: block; font-size: 12px; margin-top: 3px; color: var(--muted); }
.brand-symbol { width: 34px; height: 34px; display: grid; grid-template-columns: repeat(2, 1fr); gap: 2px; transform: rotate(-8deg); }
.brand-symbol i { display: block; background: var(--ink); }
.brand-symbol i:nth-child(2), .brand-symbol i:nth-child(3) { background: var(--accent); }
.topbar-meta { display: flex; align-items: center; gap: 15px; color: var(--muted); font-size: 13px; white-space: nowrap; }
.meta-divider { height: 16px; border-left: 1px solid var(--rule); }

.intro { display: flex; justify-content: space-between; align-items: end; gap: 24px; padding: 23px 0 21px; }
.eyebrow { margin: 0 0 10px; color: var(--accent-dark); font-size: 11px; font-weight: 800; letter-spacing: .08em; }
h1 { font-family: Georgia, "Times New Roman", serif; font-size: clamp(38px, 4vw, 54px); line-height: 1; letter-spacing: -.055em; font-weight: 600; margin: 0 0 9px; }
.intro-copy { max-width: 760px; margin: 0; font-size: 13px; color: var(--muted); line-height: 1.45; }
.session-status { text-align: right; flex: none; padding-bottom: 5px; }
.session-status span { display: block; font-size: 28px; line-height: 1; font-weight: 750; font-variant-numeric: tabular-nums; letter-spacing: -.04em; }
.session-status small { display: block; margin-top: 7px; color: var(--muted); font-size: 12px; }

.step-nav { display: grid; grid-template-columns: repeat(5, 1fr); border-top: 1px solid var(--rule); border-bottom: 1px solid var(--rule); }
.step-link { min-height: 60px; appearance: none; border: 0; background: transparent; text-align: left; color: var(--muted); padding: 10px 12px 10px 0; display: flex; align-items: center; gap: 16px; position: relative; }
.step-link:not(:first-child) { padding-left: 26px; border-left: 1px solid var(--rule); }
.step-link .number { font-family: Georgia, serif; font-size: 22px; color: #a4aaa1; }
.step-link .name { font-size: 14px; font-weight: 650; }
.step-link .duration { display: block; font-size: 11px; font-weight: 450; margin-top: 3px; color: var(--muted); }
.step-link.active .number, .step-link.active .name { color: var(--accent-dark); }
.step-link.complete .number { color: var(--good); }
.step-link.active::after { content: ""; position: absolute; height: 3px; background: var(--accent); bottom: -1px; left: 0; right: 0; }
.step-link:disabled { opacity: .55; }
.step-link:focus-visible, button:focus-visible, a:focus-visible { outline: 3px solid var(--accent); outline-offset: 3px; }

.workspace { display: grid; grid-template-columns: minmax(0, min(48vw, calc(100svh - 340px))) minmax(300px, 1fr); gap: clamp(35px, 5vw, 80px); padding: 24px 0 40px; align-items: start; }
.board-region { min-width: 0; }
.board-topline, .board-bottomline { display: flex; justify-content: space-between; align-items: center; gap: 15px; }
.board-topline { min-height: 31px; margin-bottom: 15px; }
.board-topline > span { color: var(--muted); font-size: 12px; font-weight: 700; letter-spacing: .075em; }
.quiet-button { background: none; color: var(--muted); border: 0; padding: 4px 0; font-size: 12px; }
.quiet-button:hover { color: var(--accent-dark); }
.quiet-button span { font-size: 18px; vertical-align: -1px; margin-left: 3px; }
.board-frame { width: 100%; aspect-ratio: 1; padding: 9px; background: var(--paper-strong); box-shadow: 0 17px 48px #2c35231c, 0 0 0 1px #d7d7cd; position: relative; }
.board { display: grid; grid-template-columns: repeat(8, 1fr); grid-template-rows: repeat(8, 1fr); width: 100%; height: 100%; }
.square { position: relative; padding: 0; border: 0; border-radius: 0; display: grid; place-items: center; transition: box-shadow .16s ease, filter .16s ease; }
.square.light { background: var(--board-light); }
.square.dark { background: var(--board-dark); }
.square:not(:disabled):hover { filter: brightness(1.08); box-shadow: inset 0 0 0 3px #fff9; z-index: 1; }
.square:disabled { opacity: 1; }
.square img { width: 88%; height: 88%; object-fit: contain; pointer-events: none; user-select: none; filter: drop-shadow(0 2px 1px #1112); }
.square.selected { box-shadow: inset 0 0 0 4px var(--accent); z-index: 1; }
.square.target { box-shadow: inset 0 0 0 4px var(--accent); z-index: 1; }
.square.last-move::before { content: ""; position: absolute; inset: 0; background: #e2b86755; pointer-events: none; }
.square.last-move img { z-index: 1; }
.square.correct { box-shadow: inset 0 0 0 5px var(--good); z-index: 1; }
.square.incorrect { box-shadow: inset 0 0 0 5px var(--bad); z-index: 1; }
.square.focus-square { box-shadow: inset 0 0 0 4px var(--accent-dark); z-index: 1; }
.board-overlay { position: absolute; inset: 9px; display: flex; align-items: center; justify-content: center; text-align: center; padding: 25px; background: #26382f; color: #f7f2e7; overflow: hidden; }
.board-overlay[hidden] { display: none; }
.board-overlay::before { content: ""; position: absolute; inset: 17px; border: 1px solid #f7f2e72c; pointer-events: none; }
.cover-inner { position: relative; max-width: 360px; }
.cover-eyebrow { display: block; font-size: 12px; font-weight: 700; letter-spacing: .13em; color: #c9d4c9; margin-bottom: 16px; }
.cover-move { display: block; font-family: Georgia, serif; font-size: clamp(45px, 6vw, 88px); line-height: 1; letter-spacing: -.06em; margin-bottom: 20px; }
.cover-caption { font-size: 14px; line-height: 1.45; color: #d2dcd1; }
.board-bottomline { min-height: 34px; margin-top: 10px; color: var(--muted); font-size: 12px; }
.board-bottomline span:first-child { max-width: 75%; }

.task-panel { min-height: 490px; padding-top: 13px; }
.panel-kicker { color: var(--accent-dark); font-size: 11px; font-weight: 800; letter-spacing: .14em; margin: 0 0 14px; }
.task-panel h2 { font-family: Georgia, "Times New Roman", serif; font-size: clamp(33px, 3.1vw, 47px); font-weight: 500; letter-spacing: -.045em; line-height: 1.08; margin: 0 0 18px; }
.panel-copy { max-width: 490px; color: var(--muted); font-size: 15px; line-height: 1.58; margin: 0 0 26px; }
.panel-copy strong { color: var(--ink); }
.timer-line { display: flex; justify-content: space-between; align-items: baseline; padding: 17px 0 12px; border-top: 1px solid var(--rule); font-size: 13px; color: var(--muted); }
.timer-line strong { color: var(--ink); font-size: 25px; font-weight: 650; font-variant-numeric: tabular-nums; letter-spacing: -.04em; }
.timer-track { width: 100%; height: 4px; background: #dbded6; margin-bottom: 27px; }
.timer-track span { display: block; width: 0; height: 100%; background: var(--accent); transition: width .2s linear; }
.large-prompt { display: flex; align-items: baseline; gap: 13px; padding: 20px 0; margin-bottom: 18px; border-top: 1px solid var(--rule); border-bottom: 1px solid var(--rule); }
.large-prompt strong { font-family: Georgia, serif; font-size: 69px; letter-spacing: -.065em; line-height: 1; }
.large-prompt span { font-size: 13px; color: var(--muted); }
.stat-line { display: flex; align-items: baseline; justify-content: space-between; color: var(--muted); font-size: 13px; margin: 12px 0 28px; }
.stat-line strong { color: var(--ink); font-size: 16px; }
.actions { display: flex; align-items: center; flex-wrap: wrap; gap: 13px; margin-top: 23px; }
.primary-button, .secondary-button { min-height: 46px; border-radius: 4px; padding: 11px 20px; font-size: 13px; font-weight: 700; transition: transform .15s ease, background .15s ease; }
.primary-button { border: 1px solid var(--accent); background: var(--accent); color: #fff; }
.primary-button:hover { background: var(--accent-dark); transform: translateY(-2px); }
.secondary-button { border: 1px solid #aeb6aa; background: transparent; color: var(--ink); }
.secondary-button:hover { background: #e8ebe2; transform: translateY(-2px); }
.text-button { border: 0; color: var(--muted); background: none; padding: 9px 0; font-size: 13px; text-decoration: underline; text-underline-offset: 4px; }
.text-button:hover { color: var(--accent-dark); }
.inline-note { color: var(--muted); font-size: 12px; line-height: 1.5; margin: 18px 0 0; }
.feedback { min-height: 23px; margin: 14px 0 0; font-size: 13px; font-weight: 650; }
.feedback.good { color: var(--good); }
.feedback.bad { color: var(--bad); }
.feedback.neutral { color: var(--muted); }

.level-picker { display: flex; flex-wrap: wrap; gap: 7px; margin: 5px 0 26px; }
.option-label { margin: 12px 0 4px; color: var(--muted); font-size: 12px; font-weight: 700; }
.option-label + .level-picker { margin-bottom: 15px; }
.level-picker button { border: 1px solid var(--rule); background: transparent; color: var(--muted); border-radius: 3px; padding: 8px 10px; font-size: 12px; font-weight: 650; }
.level-picker button.active { border-color: var(--ink); background: var(--ink); color: white; }
.visual-tabs { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); border-top: 1px solid var(--rule); border-bottom: 1px solid var(--rule); margin: 3px 0 27px; }
.visual-tabs button { min-height: 46px; padding: 10px 8px 9px 0; border: 0; border-bottom: 2px solid transparent; background: transparent; color: var(--muted); text-align: left; font-size: 12px; font-weight: 650; }
.visual-tabs button:nth-child(even) { padding-left: 14px; border-left: 1px solid var(--rule); }
.visual-tabs button:nth-child(n + 3) { border-top: 1px solid var(--rule); }
.visual-tabs button:hover { color: var(--ink); }
.visual-tabs button.active { color: var(--accent-dark); border-bottom-color: var(--accent); }
.tray-heading { display: flex; justify-content: space-between; align-items: baseline; gap: 12px; border-top: 1px solid var(--rule); padding: 13px 0 6px; color: var(--muted); font-size: 12px; font-weight: 700; }
.tray-heading strong { color: var(--ink); font-variant-numeric: tabular-nums; }
.piece-tray { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); margin-bottom: 14px; }
.piece-token { display: flex; align-items: center; gap: 8px; width: 100%; min-height: 44px; padding: 5px 7px 5px 0; border: 0; border-bottom: 1px solid var(--rule); background: transparent; color: var(--ink); text-align: left; font-size: 11px; }
.piece-token:nth-child(even) { padding-left: 9px; border-left: 1px solid var(--rule); }
.piece-token:hover, .piece-token.active { background: #e8ebe2; }
.piece-token.active { box-shadow: inset 0 0 0 2px var(--accent); }
.piece-token img, .captured-pieces img { width: 31px; height: 31px; object-fit: contain; flex: none; }
.capture-row { display: flex; align-items: stretch; gap: 11px; margin: 5px 0 8px; }
.capture-bin { min-width: 136px; min-height: 45px; border: 1px dashed #879484; background: #edf0e8; border-radius: 3px; color: var(--ink); font-size: 12px; font-weight: 700; }
.capture-bin:disabled { opacity: .65; }
.capture-bin:not(:disabled):hover { background: #e0e8dc; border-color: var(--accent); }
.capture-bin span { color: var(--accent-dark); margin-left: 6px; }
.captured-pieces { display: flex; align-items: center; flex-wrap: wrap; gap: 5px; min-height: 45px; color: var(--muted); font-size: 11px; }
.captured-pieces button { width: 38px; height: 38px; padding: 2px; border: 1px solid var(--rule); background: var(--paper-strong); border-radius: 3px; }
.captured-pieces button:hover { border-color: var(--accent); }
.move-line { display: flex; flex-wrap: wrap; gap: 7px; min-height: 43px; padding: 15px 0; border-top: 1px solid var(--rule); border-bottom: 1px solid var(--rule); margin-top: 19px; }
.move-pill { display: inline-block; background: #e5e7df; padding: 5px 8px; border-radius: 3px; font-size: 12px; font-weight: 650; font-variant-numeric: tabular-nums; }
.move-pill.current { background: var(--ink); color: white; }
.question-count { font-size: 12px; font-weight: 750; color: var(--muted); letter-spacing: .08em; margin-bottom: 12px; }
.choice-list { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 9px; margin-top: 24px; }
.choice-list button { min-height: 52px; text-align: left; padding: 12px 15px; border: 1px solid #b7beb3; background: #fbfaf5; border-radius: 4px; color: var(--ink); font-size: 13px; }
.choice-list button:hover { border-color: var(--accent); background: #fff; }
.review-score { font-family: Georgia, serif; font-size: 70px; line-height: 1; letter-spacing: -.05em; margin-bottom: 17px; }
.review-score span { color: var(--muted); font-size: 28px; }
.review-list { list-style: none; padding: 0; margin: 22px 0 24px; border-top: 1px solid var(--rule); }
.review-list li { display: flex; gap: 12px; align-items: baseline; padding: 10px 0; border-bottom: 1px solid var(--rule); color: var(--muted); font-size: 13px; line-height: 1.35; }
.review-list strong { width: 17px; flex: none; color: var(--good); }
.review-list .miss { color: var(--bad); }
.replay { display: flex; align-items: center; justify-content: space-between; gap: 10px; margin: 14px 0 20px; }
.replay button { background: none; border: 1px solid var(--rule); border-radius: 3px; min-width: 36px; min-height: 32px; }
.replay button:hover { background: #e7e8df; }
.replay span { color: var(--muted); font-size: 12px; }
.summary-grid { display: grid; grid-template-columns: repeat(4, 1fr); border-top: 1px solid var(--rule); border-bottom: 1px solid var(--rule); margin: 30px 0; }
.summary-grid > div { padding: 17px 9px 18px 0; }
.summary-grid > div:not(:first-child) { border-left: 1px solid var(--rule); padding-left: 14px; }
.summary-grid strong { display: block; font-size: 26px; letter-spacing: -.04em; }
.summary-grid span { display: block; color: var(--muted); font-size: 11px; margin-top: 5px; }
.external-link { display: inline-flex; align-items: center; gap: 7px; margin-top: 13px; color: var(--accent-dark); font-size: 13px; font-weight: 700; text-underline-offset: 4px; }
.footer { display: flex; justify-content: space-between; gap: 15px; padding: 22px 0 35px; border-top: 1px solid var(--rule); color: var(--muted); font-size: 11px; }
.footer a:hover { color: var(--accent-dark); }

@media (max-width: 900px) {
  .workspace { grid-template-columns: 1fr; max-width: 670px; margin: auto; gap: 14px; }
  .task-panel { padding-top: 14px; min-height: 0; }
  .intro { align-items: start; }
}
@media (max-width: 600px) {
  .app-shell { padding: 0 16px; }
  .topbar { min-height: 71px; }
  .brand strong { font-size: 12px; letter-spacing: .07em; }
  .brand small { font-size: 10px; }
  .brand-symbol { width: 27px; height: 27px; }
  .topbar-meta { display: block; text-align: right; font-size: 11px; line-height: 1.45; }
  .meta-divider { display: none; }
  .topbar-meta span { display: block; }
  .intro { padding: 26px 0 25px; }
  .intro-copy { font-size: 13px; }
  h1 { font-size: 48px; }
  .session-status { display: none; }
  .step-nav { grid-template-columns: repeat(3, 1fr); }
  .step-link { min-height: 58px; gap: 7px; padding-right: 5px; }
  .step-link:not(:first-child) { padding-left: 9px; }
  .step-link:nth-child(4) { padding-left: 0; border-left: 0; }
  .step-link:nth-child(n + 4) { border-top: 1px solid var(--rule); }
  .step-link .number { font-size: 18px; }
  .step-link .name { font-size: 11px; }
  .step-link .duration { font-size: 10px; }
  .workspace { padding: 20px 0 36px; }
  .board-frame { padding: 5px; }
  .board-overlay { inset: 5px; }
  .board-topline { margin-bottom: 8px; }
  .board-region.coordinates .board-topline > span { color: var(--ink); font-family: Georgia, serif; font-size: 24px; letter-spacing: -.03em; font-weight: 600; }
  .board-bottomline { font-size: 11px; }
  .task-panel h2 { font-size: 36px; }
  .large-prompt strong { font-size: 58px; }
  .summary-grid { grid-template-columns: repeat(2, 1fr); }
  .summary-grid > div:nth-child(3) { border-left: 0; padding-left: 0; }
  .summary-grid > div:nth-child(n + 3) { border-top: 1px solid var(--rule); }
  .footer { display: block; line-height: 1.7; }
  .footer span { display: block; }
}
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { transition: none !important; animation: none !important; }
}