:root {
  --bg: #f5f1ea;
  --bg-soft: #fbf8f2;
  --surface: rgba(255, 255, 255, 0.74);
  --surface-strong: #fffdf9;
  --ink: #171717;
  --muted: #6a665d;
  --line: rgba(23, 23, 23, 0.1);
  --accent: #4e6b73;
  --accent-soft: rgba(78, 107, 115, 0.12);
  --warning: #b97839;
  --warning-soft: rgba(185, 120, 57, 0.12);
  --success: #2d5a4f;
  --success-soft: rgba(45, 90, 79, 0.12);
  --shadow: 0 28px 90px rgba(26, 25, 22, 0.12);
  --radius-xl: 34px;
  --radius-lg: 24px;
  --radius-md: 18px;
  --radius-sm: 14px;
}

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  min-width: 320px;
  min-height: 100dvh;
  background: linear-gradient(180deg, #f6f2eb 0%, #f2ede4 100%);
  color: var(--ink);
  font-family: "Avenir Next", "SF Pro Display", "PingFang SC", "Hiragino Sans GB", "Noto Sans CJK SC", sans-serif;
  line-height: 1.6;
}

button,
input,
select,
textarea {
  font: inherit;
}

button {
  cursor: pointer;
}

a {
  color: inherit;
}

.skip-link {
  position: absolute;
  top: -3rem;
  left: 1rem;
  z-index: 100;
  padding: 0.8rem 1rem;
  border-radius: 999px;
  background: var(--ink);
  color: #fff;
  text-decoration: none;
}

.skip-link:focus {
  top: 1rem;
}

.page-backdrop {
  position: fixed;
  inset: 0;
  overflow: hidden;
  pointer-events: none;
}

.page-grid {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(23, 23, 23, 0.03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(23, 23, 23, 0.03) 1px, transparent 1px);
  background-size: 36px 36px;
  mask-image: linear-gradient(180deg, rgba(0, 0, 0, 0.55), transparent 88%);
}

.page-orb {
  position: absolute;
  border-radius: 50%;
  filter: blur(2px);
}

.page-orb-a {
  width: 16rem;
  height: 16rem;
  top: -5rem;
  right: -3rem;
  background: radial-gradient(circle, rgba(78, 107, 115, 0.3), rgba(78, 107, 115, 0.02) 72%);
}

.page-orb-b {
  width: 18rem;
  height: 18rem;
  bottom: -7rem;
  left: -7rem;
  background: radial-gradient(circle, rgba(185, 120, 57, 0.24), rgba(185, 120, 57, 0.02) 70%);
}

.app-shell {
  position: relative;
  z-index: 1;
  display: flex;
  justify-content: center;
  min-height: 100dvh;
  padding: 1rem;
}

.phone-stage {
  width: min(100%, 430px);
  min-height: calc(100dvh - 2rem);
  display: flex;
  flex-direction: column;
  gap: 1rem;
  padding: 1rem;
  border: 1px solid rgba(23, 23, 23, 0.08);
  border-radius: calc(var(--radius-xl) + 8px);
  background: rgba(250, 247, 241, 0.76);
  box-shadow: var(--shadow);
  backdrop-filter: blur(16px);
}

.chrome,
.hud,
.screen,
.panel,
.node-card,
.option-card,
.feedback-card,
.summary-step,
.summary-card,
.helper-card,
.notice {
  border: 1px solid var(--line);
  background: var(--surface);
  backdrop-filter: blur(14px);
}

.chrome {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 0.9rem 1rem;
  border-radius: var(--radius-lg);
}

.brand-kicker,
.eyebrow,
.micro-label,
.meta-label {
  margin: 0;
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--muted);
}

.chrome h1 {
  margin: 0.25rem 0 0;
  font-family: "Iowan Old Style", "Palatino Linotype", "Book Antiqua", "Songti SC", "STSong", serif;
  font-size: 1.2rem;
  font-weight: 400;
}

.ghost-button,
.shortcut-button,
.primary-button,
.secondary-button,
.option-card,
.node-card {
  min-height: 44px;
  border-radius: 999px;
  transition:
    background-color 180ms ease,
    border-color 180ms ease,
    color 180ms ease,
    transform 180ms ease,
    box-shadow 180ms ease;
}

.ghost-button,
.shortcut-button,
.primary-button,
.secondary-button {
  padding: 0.85rem 1rem;
  border: 1px solid var(--line);
}

.ghost-button {
  background: transparent;
  color: var(--muted);
}

.shortcut-button {
  background: var(--warning-soft);
  color: #7b4f20;
  border-color: rgba(185, 120, 57, 0.22);
}

.shortcut-button[hidden] {
  display: none;
}

.primary-button {
  background: var(--ink);
  color: #fff;
}

.secondary-button {
  background: transparent;
  color: var(--ink);
}

.ghost-button:hover,
.ghost-button:focus-visible,
.secondary-button:hover,
.secondary-button:focus-visible {
  background: rgba(23, 23, 23, 0.04);
}

.shortcut-button:hover,
.shortcut-button:focus-visible {
  background: rgba(185, 120, 57, 0.18);
}

.primary-button:hover,
.primary-button:focus-visible {
  transform: translateY(-1px);
  box-shadow: 0 12px 20px rgba(23, 23, 23, 0.16);
}

.ghost-button:focus-visible,
.shortcut-button:focus-visible,
.primary-button:focus-visible,
.secondary-button:focus-visible,
.option-card:focus-visible,
.node-card:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

.hud {
  display: grid;
  gap: 0.9rem;
  padding: 1rem;
  border-radius: var(--radius-lg);
}

.hud-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.9rem;
}

.hud-row-secondary {
  align-items: flex-end;
}

.hud-label {
  margin: 0;
  font-size: 0.78rem;
  color: var(--muted);
}

.hud-value {
  margin: 0.2rem 0 0;
  font-weight: 700;
  letter-spacing: -0.01em;
}

.score-pill {
  flex-shrink: 0;
  min-width: 7.8rem;
  padding: 0.8rem 0.9rem;
  border-radius: var(--radius-md);
  background: rgba(23, 23, 23, 0.04);
  text-align: right;
}

.score-pill span {
  display: block;
  font-size: 0.75rem;
  color: var(--muted);
}

.score-pill strong {
  display: block;
  margin-top: 0.15rem;
  font-size: 1.2rem;
  letter-spacing: -0.03em;
}

.progress-track {
  overflow: hidden;
  height: 8px;
  border-radius: 999px;
  background: rgba(23, 23, 23, 0.08);
}

.progress-track span {
  display: block;
  height: 100%;
  width: 0;
  border-radius: inherit;
  background: linear-gradient(90deg, var(--accent), #7fa0a7);
  transition: width 260ms ease;
}

.live-region {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  clip-path: inset(50%);
  white-space: nowrap;
}

.game-stage {
  flex: 1;
  display: flex;
}

.screen {
  width: 100%;
  display: grid;
  gap: 1rem;
  padding: 1.25rem;
  border-radius: var(--radius-xl);
  animation: screen-enter 320ms ease;
}

.screen-head {
  display: grid;
  gap: 0.45rem;
}

.screen-head h2,
.summary-card h2 {
  margin: 0;
  font-family: "Iowan Old Style", "Palatino Linotype", "Book Antiqua", "Songti SC", "STSong", serif;
  font-size: clamp(2rem, 10vw, 3.1rem);
  line-height: 0.96;
  letter-spacing: -0.04em;
  font-weight: 400;
}

.screen-head h3,
.feedback-card h3,
.summary-step h3,
.option-card strong,
.node-card strong {
  margin: 0;
}

.screen-head p,
.summary-card p,
.panel p,
.feedback-card p,
.helper-card p,
.note-line,
.method-list li,
.tiny-list li {
  margin: 0;
  color: #2b2a27;
}

.meta-strip {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
}

.meta-chip {
  padding: 0.45rem 0.8rem;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.44);
  color: var(--muted);
  font-size: 0.82rem;
}

.panel,
.feedback-card,
.summary-card,
.helper-card,
.notice {
  display: grid;
  gap: 0.8rem;
  padding: 1rem;
  border-radius: var(--radius-lg);
}

.panel-quiet {
  background: rgba(255, 255, 255, 0.5);
}

.notice {
  color: #71491d;
  background: var(--warning-soft);
  border-color: rgba(185, 120, 57, 0.2);
}

.method-list,
.tiny-list,
.summary-steps,
.summary-grid {
  display: grid;
  gap: 0.75rem;
  padding: 0;
  margin: 0;
  list-style: none;
}

.method-list li,
.tiny-list li {
  padding-left: 1.05rem;
  position: relative;
}

.method-list li::before,
.tiny-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.65rem;
  width: 0.45rem;
  height: 0.45rem;
  border-radius: 50%;
  background: var(--accent);
}

.option-grid,
.node-grid {
  display: grid;
  gap: 0.75rem;
}

.node-grid {
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.option-card,
.node-card {
  width: 100%;
  display: grid;
  gap: 0.45rem;
  padding: 1rem;
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  background: rgba(255, 255, 255, 0.45);
  color: var(--ink);
  text-align: left;
}

.option-card span,
.node-card span {
  color: var(--muted);
  font-size: 0.92rem;
  line-height: 1.5;
}

.option-card.is-selected,
.node-card.is-selected,
.node-card.is-open {
  border-color: rgba(78, 107, 115, 0.38);
  background: rgba(78, 107, 115, 0.12);
}

.option-card.is-warning {
  border-color: rgba(185, 120, 57, 0.3);
}

.node-detail {
  padding: 0.75rem 0.85rem;
  border-radius: var(--radius-sm);
  background: rgba(23, 23, 23, 0.03);
  color: var(--muted);
  font-size: 0.86rem;
}

.action-bar {
  display: grid;
  gap: 0.75rem;
}

.action-bar .secondary-button,
.action-bar .primary-button {
  width: 100%;
}

.feedback-card {
  border-color: rgba(78, 107, 115, 0.18);
}

.feedback-card.is-warning {
  border-color: rgba(185, 120, 57, 0.24);
  background: rgba(255, 249, 243, 0.88);
}

.feedback-title {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
}

.feedback-tag,
.mini-badge {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.35rem 0.7rem;
  border-radius: 999px;
  background: var(--accent-soft);
  color: var(--accent);
  font-size: 0.78rem;
  font-weight: 700;
}

.feedback-card.is-warning .feedback-tag {
  background: var(--warning-soft);
  color: #7b4f20;
}

.theory-note {
  padding: 0.9rem 1rem;
  border-radius: var(--radius-md);
  background: rgba(23, 23, 23, 0.04);
}

.theory-note strong,
.summary-step strong,
.summary-card strong {
  font-weight: 800;
}

.ai-panel {
  border-color: rgba(185, 120, 57, 0.22);
  background: rgba(255, 250, 244, 0.94);
}

.ai-panel .tiny-list li::before {
  background: var(--warning);
}

.summary-card {
  gap: 1rem;
}

.summary-grid {
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.summary-metric {
  padding: 0.9rem 1rem;
  border-radius: var(--radius-md);
  background: rgba(23, 23, 23, 0.04);
}

.summary-metric strong {
  display: block;
  margin-top: 0.25rem;
  font-size: 1.15rem;
}

.summary-step {
  padding: 1rem;
  border-radius: var(--radius-lg);
}

.step-index {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 2rem;
  height: 2rem;
  border-radius: 50%;
  background: var(--ink);
  color: #fff;
  font-size: 0.84rem;
  font-weight: 800;
}

.summary-actions {
  display: grid;
  gap: 0.75rem;
}

.helper-card {
  background: rgba(255, 255, 255, 0.54);
}

.noscript-card {
  margin: 1rem;
  padding: 1rem;
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  background: var(--surface-strong);
}

.micro-copy {
  color: var(--muted);
  font-size: 0.88rem;
}

@keyframes screen-enter {
  from {
    opacity: 0;
    transform: translateY(12px);
  }

  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@media (max-width: 479px) {
  .app-shell {
    padding: 0;
  }

  .phone-stage {
    width: 100%;
    min-height: 100dvh;
    border-radius: 0;
    border-left: none;
    border-right: none;
    box-shadow: none;
  }

  .screen,
  .hud,
  .chrome {
    padding: 1rem;
  }

  .node-grid,
  .summary-grid {
    grid-template-columns: 1fr;
  }

  .hud-row {
    align-items: flex-start;
    flex-direction: column;
  }

  .score-pill,
  .shortcut-button {
    width: 100%;
  }
}

@media (min-width: 700px) {
  .app-shell {
    padding: 2.25rem;
  }

  .phone-stage {
    min-height: min(860px, calc(100dvh - 4.5rem));
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  .screen,
  .progress-track span,
  .ghost-button,
  .shortcut-button,
  .primary-button,
  .secondary-button,
  .option-card,
  .node-card {
    animation: none;
    transition: none;
  }
}