:root {
  --paper: #f5f0e5;
  --paper-light: #fffdf8;
  --ink: #173d35;
  --ink-soft: #36544c;
  --vermilion: #b5432f;
  --vermilion-dark: #90301f;
  --line: #cfc7b8;
  --muted: #6f736c;
  --shadow: 0 14px 32px rgb(31 49 42 / 8%);
  color: var(--ink);
  background: var(--paper);
  font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", "Microsoft YaHei", "PingFang SC", sans-serif;
  line-height: 1.7;
  text-rendering: optimizeLegibility;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  min-width: 0;
  margin: 0;
  background:
    linear-gradient(rgb(255 253 248 / 84%), rgb(255 253 248 / 84%)),
    repeating-linear-gradient(0deg, rgb(23 61 53 / 2%) 0, rgb(23 61 53 / 2%) 1px, transparent 1px, transparent 5px),
    var(--paper);
  color: var(--ink);
}

body > a:first-child {
  position: fixed;
  z-index: 10;
  top: 0.75rem;
  left: 0.75rem;
  padding: 0.5rem 0.75rem;
  transform: translateY(-180%);
  border: 1px solid var(--ink);
  background: var(--paper-light);
  color: var(--ink);
  text-decoration: none;
}

body > a:first-child:focus {
  transform: translateY(0);
}

a {
  color: var(--ink);
  text-decoration-thickness: 0.08em;
  text-underline-offset: 0.18em;
}

a:hover {
  color: var(--vermilion-dark);
}

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

.site-header,
main,
footer {
  width: min(1120px, calc(100% - 2rem));
  margin-inline: auto;
}

.site-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem 2rem;
  min-height: 4.75rem;
  border-bottom: 1px solid var(--line);
}

.site-header > a {
  font-family: ui-serif, Georgia, "Songti SC", SimSun, serif;
  font-size: 1.08rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  text-decoration: none;
}

.site-header nav,
.case-tabs,
.stepper-controls {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.4rem 0.85rem;
}

.site-header nav a {
  color: var(--ink-soft);
  font-size: 0.92rem;
}

.hero {
  display: grid;
  grid-template-columns: minmax(0, 1.35fr) minmax(15rem, 0.65fr);
  column-gap: clamp(2rem, 8vw, 8rem);
  align-items: end;
  min-height: 31rem;
  padding-block: clamp(5rem, 12vw, 9rem) clamp(3rem, 7vw, 5.75rem);
  border-bottom: 1px solid var(--line);
}

.hero > * {
  grid-column: 1;
}

.hero::after {
  grid-column: 2;
  grid-row: 1 / span 4;
  align-self: stretch;
  content: "教招\A 出题官";
  white-space: pre-line;
  padding: 1.25rem;
  border-top: 5px solid var(--vermilion);
  border-bottom: 1px solid var(--line);
  color: var(--ink-soft);
  font-family: ui-serif, Georgia, "Songti SC", SimSun, serif;
  font-size: clamp(2rem, 5vw, 4.5rem);
  font-weight: 700;
  line-height: 1.08;
  letter-spacing: 0.12em;
}

.eyebrow {
  margin: 0 0 0.85rem;
  color: var(--vermilion-dark);
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0.14em;
}

h1,
h2,
h3,
h4,
h5 {
  font-family: ui-serif, Georgia, "Songti SC", SimSun, serif;
  line-height: 1.25;
}

h1,
h2,
h3,
h4,
h5,
p {
  overflow-wrap: anywhere;
}

h1 {
  max-width: 11.5em;
  margin: 0;
  font-size: clamp(2.35rem, 5.8vw, 5.15rem);
  letter-spacing: -0.04em;
}

h2 {
  max-width: 18em;
  margin: 0 0 2.4rem;
  font-size: clamp(1.8rem, 4vw, 3.2rem);
  letter-spacing: -0.025em;
}

h3 {
  margin: 0 0 0.65rem;
  font-size: 1.22rem;
}

h4 {
  margin: 1.7rem 0 0.65rem;
  font-size: 1.08rem;
}

h5 {
  margin: 0 0 0.5rem;
  font-size: 1rem;
}

h6 {
  margin: 1.1rem 0 0.45rem;
  color: var(--vermilion-dark);
  font-size: 0.92rem;
}

.hero > p:not(.eyebrow) {
  max-width: 39rem;
  margin: 1.25rem 0 2rem;
  color: var(--ink-soft);
  font-size: 1.08rem;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.65rem;
}

.section {
  padding-block: clamp(3.5rem, 9vw, 7rem);
  border-bottom: 1px solid var(--line);
}

.section > .eyebrow {
  margin-bottom: 0.55rem;
}

.ability-grid,
.boundary-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 0;
  margin: 0;
  padding: 0;
  list-style: none;
  border-top: 1px solid var(--line);
  border-left: 1px solid var(--line);
}

.ability-grid > li,
.boundary-grid > li {
  min-width: 0;
  padding: 1.4rem;
  border-right: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  background: rgb(255 253 248 / 46%);
}

.ability-grid h3 {
  color: var(--ink);
}

.ability-grid p,
.boundary-grid > li {
  margin: 0;
  color: var(--ink-soft);
}

.demo-shell {
  position: relative;
}

.demo-shell > p:not(.eyebrow) {
  max-width: 46rem;
  margin: -1.55rem 0 2rem;
  color: var(--ink-soft);
}

.demo-content {
  display: grid;
  grid-template-columns: minmax(13rem, 0.72fr) minmax(0, 1.28fr);
  gap: 1.15rem;
  align-items: start;
}

.safety-note {
  grid-column: 1 / -1;
  margin: 0;
  padding: 0.9rem 1rem;
  border-left: 4px solid var(--vermilion);
  background: #f0e5d7;
  color: #563227;
  font-size: 0.92rem;
}

.safety-note::before {
  content: "提示：";
  font-weight: 700;
}

.case-tabs,
.stepper,
.candidate-list,
.demo-content > section:not(.stepper):not(.candidate-list),
.fallback-card {
  min-width: 0;
  border: 1px solid var(--line);
  background: var(--paper-light);
  box-shadow: var(--shadow);
}

.case-tabs {
  padding: 0.8rem;
}

.stepper {
  padding: clamp(1.25rem, 3vw, 2.15rem);
}

.stepper > p:nth-of-type(2) {
  color: var(--vermilion-dark);
  font-size: 0.9rem;
  font-weight: 700;
}

.stepper-controls {
  grid-column: 2;
  justify-content: flex-end;
  padding: 0.35rem 0;
}

.candidate-list,
.demo-content > section:not(.stepper):not(.candidate-list),
.fallback-card {
  grid-column: 1 / -1;
  padding: clamp(1.25rem, 3vw, 2.15rem);
}

.candidate-list > article,
.demo-content > section:not(.stepper):not(.candidate-list) > article {
  margin-top: 1rem;
  padding: 1.15rem;
  border-top: 3px solid var(--ink);
  background: #f7f2e9;
}

.candidate-list ul,
.demo-content ol,
#standards ol {
  padding-left: 1.35rem;
}

.candidate-list li,
.demo-content li,
#standards li {
  overflow-wrap: anywhere;
}

.answer-distribution {
  padding: 0.8rem 0.9rem;
  border-left: 3px solid var(--ink);
  background: #eee7da;
  color: var(--ink-soft);
  font-weight: 650;
}

.fallback-card {
  border-top: 4px solid var(--vermilion);
}

.fallback-card > section {
  margin-top: 1.2rem;
  padding-top: 0.2rem;
  border-top: 1px solid var(--line);
}

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

.button {
  display: inline-flex;
  min-height: 2.55rem;
  align-items: center;
  justify-content: center;
  max-width: 100%;
  padding: 0.56rem 0.8rem;
  border: 1px solid var(--ink);
  border-radius: 0;
  background: transparent;
  color: var(--ink);
  font: inherit;
  font-size: 0.92rem;
  line-height: 1.35;
  text-align: center;
  text-decoration: none;
  cursor: pointer;
  overflow-wrap: anywhere;
  transition: background-color 160ms ease, border-color 160ms ease, color 160ms ease, transform 160ms ease;
}

.button:hover {
  border-color: var(--vermilion-dark);
  background: var(--vermilion-dark);
  color: var(--paper-light);
}

.button:active {
  transform: translateY(1px);
}

.button:disabled,
.button:disabled:hover {
  border-color: var(--line);
  background: #e8e2d7;
  color: #6a6b66;
  cursor: not-allowed;
  transform: none;
}

.button[aria-pressed="true"] {
  border-color: var(--vermilion-dark);
  background: #f1dbd1;
  color: #6e2519;
  font-weight: 700;
}

.button[aria-pressed="true"]::before {
  content: "✓ ";
}

.button-primary {
  border-color: var(--vermilion);
  background: var(--vermilion);
  color: var(--paper-light);
  font-weight: 700;
}

.button-primary:hover {
  border-color: var(--vermilion-dark);
  background: var(--vermilion-dark);
  color: var(--paper-light);
}

#results p,
#standards ol {
  max-width: 47rem;
  color: var(--ink-soft);
  font-size: 1.06rem;
}

#standards ol {
  display: grid;
  gap: 0.8rem;
  margin: 0;
  padding: 0;
  list-style: none;
  counter-reset: standard;
}

#standards li {
  counter-increment: standard;
  display: grid;
  grid-template-columns: 2.2rem minmax(0, 1fr);
  gap: 0.65rem;
  padding-top: 0.8rem;
  border-top: 1px solid var(--line);
}

#standards li::before {
  content: "0" counter(standard);
  color: var(--vermilion-dark);
  font-family: ui-monospace, SFMono-Regular, Consolas, monospace;
  font-size: 0.9rem;
  font-weight: 700;
}

.boundary-grid h3 {
  color: var(--vermilion-dark);
}

.boundary-grid ul {
  margin: 0;
  padding-left: 1.15rem;
}

.boundary-grid ul li + li {
  margin-top: 0.45rem;
}

footer {
  display: grid;
  grid-template-columns: minmax(0, 1.35fr) minmax(14rem, 0.65fr);
  gap: 1.5rem 3rem;
  padding-block: 1.75rem 2.3rem;
  color: var(--ink-soft);
  font-size: 0.9rem;
}

footer p {
  margin: 0.35rem 0 0;
}

footer h2 {
  margin: 0 0 0.65rem;
  font-size: 1.15rem;
}

.footer-meta {
  padding-left: 1.2rem;
  border-left: 1px solid var(--line);
}

.footer-meta .button {
  margin-top: 0.8rem;
}

::selection {
  background: #e8b8a9;
  color: #352018;
}

@media (max-width: 760px) {
  .site-header {
    align-items: flex-start;
    flex-direction: column;
    justify-content: center;
    padding-block: 0.85rem;
  }

  .hero,
  .demo-content,
  footer {
    grid-template-columns: minmax(0, 1fr);
  }

  .hero {
    min-height: 0;
    padding-block: 4rem 3.5rem;
  }

  .hero::after {
    grid-column: 1;
    grid-row: auto;
    min-height: 8rem;
    margin-top: 1rem;
    font-size: 2.4rem;
  }

  .ability-grid,
  .boundary-grid {
    grid-template-columns: minmax(0, 1fr);
  }

  .stepper-controls,
  .candidate-list,
  .demo-content > section:not(.stepper):not(.candidate-list) {
    grid-column: 1;
  }

  .stepper-controls {
    justify-content: flex-start;
  }

  .button {
    flex: 1 1 8rem;
  }

  .footer-meta {
    padding-top: 1.2rem;
    padding-left: 0;
    border-top: 1px solid var(--line);
    border-left: 0;
  }
}

@media (max-width: 360px) {
  .site-header,
  main,
  footer {
    width: min(100% - 1.25rem, 1120px);
  }

  h1 {
    font-size: 2.25rem;
  }

  .case-tabs,
  .stepper-controls {
    gap: 0.45rem;
  }

  .button {
    flex-basis: 100%;
  }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    scroll-behavior: auto !important;
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}