/* ============================================================
   手机斗地主 · 共享样式表 /assets/site.css
   包豪斯原色构成 × 深夜牌局档案
   ============================================================ */

:root {
  --color-surface: #fafafa;
  --color-surface-alt: #f0f0f0;
  --color-surface-deep: #e2e2e2;
  --color-ink: #303336;
  --color-ink-soft: #595e63;
  --color-ink-muted: #757a7f;
  --color-line: #d6d6d7;
  --color-primary: #1073da;
  --color-primary-ink: #ffffff;
  --color-primary-soft: #d9e7f6;
  --color-accent: #e80768;
  --color-accent-ink: #ffffff;
  --color-highlight: #f7cee0;
  --color-focus: #e00060;
  --color-contrast-surface: #14212e;
  --color-contrast-ink: #e4e5e7;
  --color-contrast-line: #424c57;
  --color-contrast-accent: #f93489;
  --overlay-scrim: linear-gradient(180deg, rgba(20, 33, 46, 0.35) 0%, rgba(20, 33, 46, 0.72) 55%, rgba(20, 33, 46, 0.92) 100%);
  --font-heading: "Source Han Sans SC", "Noto Sans SC", SimHei, "Microsoft YaHei", sans-serif;
  --font-body: "PingFang SC", "Microsoft YaHei", "Source Han Sans SC", sans-serif;
  --font-mono: ui-monospace, Menlo, Consolas, monospace;
  --text-xs: 9.5px;
  --text-sm: 13.5px;
  --text-base: 16px;
  --text-lg: 22.6px;
  --text-xl: 32.0px;
  --text-2xl: 45.2px;
  --text-3xl: 64.0px;
  --text-4xl: 90.4px;
  --text-display: clamp(44px, 9.1vw, 117px);
  --text-figure: clamp(37px, 6.6vw, 84px);
  --weight-heading: 887;
  --weight-body: 400;
  --leading-body: 1.67;
  --leading-heading: 1.29;
  --tracking-heading: -0.007em;
  --radius-sm: 341px;
  --radius-md: 564px;
  --radius-lg: 786px;
  --radius-pill: 999px;
  --border-thin: 2px;
  --border-thick: 2px;
  --shadow-1: none;
  --shadow-2: none;
  --space-1: 8px;
  --space-2: 16px;
  --space-3: 24px;
  --space-4: 32px;
  --space-6: 48px;
  --space-8: 64px;
  --container: 1240px;
  --measure: 72ch;
  --gutter: 24px;
  --section-y: 92px;
  --section-y-lg: 129px;
}

/* ---------- 1. reset ---------- */
*,
*::before,
*::after { box-sizing: border-box; }

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

body,
h1, h2, h3, h4, h5, h6,
p, figure, blockquote, dl, dd, ul, ol { margin: 0; }

ul, ol { padding: 0; list-style: none; }

img, svg, video { display: block; max-width: 100%; }

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

button { background: none; border: 0; padding: 0; }

table { border-collapse: collapse; border-spacing: 0; }

summary { list-style: none; }
summary::-webkit-details-marker { display: none; }

/* ---------- 2. 基础排版 ---------- */
body {
  font-family: var(--font-body);
  font-size: var(--text-base);
  font-weight: var(--weight-body);
  line-height: var(--leading-body);
  color: var(--color-ink);
  background: var(--color-surface);
  min-height: 100vh;
  overflow-x: hidden;
}

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  line-height: var(--leading-heading);
  letter-spacing: var(--tracking-heading);
  color: var(--color-ink);
  text-wrap: balance;
}

h1 { font-size: var(--text-2xl); }
h2 { font-size: var(--text-xl); }
h3 { font-size: var(--text-lg); }
h4 { font-size: var(--text-base); }

p { text-wrap: pretty; }

a { color: inherit; text-decoration: none; }

strong, b { font-weight: 700; }

::selection {
  background: var(--color-highlight);
  color: var(--color-ink);
}

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

.zone-dark :focus-visible,
.site-footer :focus-visible { outline-color: var(--color-contrast-accent); }

/* ---------- 3. 无障碍工具 ---------- */
.skip-link {
  position: fixed;
  left: var(--space-3);
  top: -140px;
  z-index: 200;
  display: inline-flex;
  align-items: center;
  padding: 10px 20px;
  background: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: var(--text-sm);
  border-radius: var(--radius-pill);
  transition: top 0.18s ease;
}
.skip-link:focus {
  top: var(--space-3);
  outline: 3px solid var(--color-focus);
  outline-offset: 3px;
}

/* ---------- 4. 布局 ---------- */
.container {
  width: 100%;
  max-width: var(--container);
  margin-inline: auto;
  padding-inline: var(--gutter);
}
.container--narrow { max-width: 860px; }

.section { padding-block: var(--section-y); }
.section--lg { padding-block: var(--section-y-lg); }
.section--tight { padding-block: var(--space-6); }

.grid {
  display: grid;
  gap: var(--gutter);
}
.grid--2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid--3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid--6 { grid-template-columns: repeat(6, minmax(0, 1fr)); }

@media (min-width: 981px) {
  .span-2 { grid-column: span 2; }
  .span-3 { grid-column: span 3; }
  .span-4 { grid-column: span 4; }
  .span-6 { grid-column: span 6; }
}

/* ---------- 5. 分区底色 ---------- */
.zone-primary {
  background: var(--color-primary-soft);
  color: var(--color-ink);
}
.zone-accent {
  background: var(--color-highlight);
  color: var(--color-ink);
}
.zone-dark {
  background: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
}
.zone-dark h1,
.zone-dark h2,
.zone-dark h3,
.zone-dark h4 { color: var(--color-contrast-ink); }
.zone-dark a { color: var(--color-contrast-ink); }

.rule-dotted {
  height: 0;
  border-top: var(--border-thin) dotted var(--color-line);
}
.rule-dotted--dark { border-top-color: var(--color-contrast-line); }

/* ---------- 6. 文字工具 ---------- */
.prose {
  max-width: var(--measure);
  font-size: var(--text-base);
  line-height: var(--leading-body);
  color: var(--color-ink);
}
.prose > * + * { margin-top: var(--space-3); }
.prose h2 { font-size: var(--text-xl); margin-top: var(--space-6); }
.prose h3 { font-size: var(--text-lg); margin-top: var(--space-4); }
.prose ul,
.prose ol {
  padding-left: 1.35em;
  list-style: disc;
}
.prose ol { list-style: decimal; }
.prose li + li { margin-top: var(--space-1); }
.prose a {
  color: var(--color-primary);
  text-decoration: underline;
  text-decoration-thickness: 2px;
  text-underline-offset: 3px;
}
.prose a:hover { color: var(--color-accent); }
.zone-dark .prose a { color: var(--color-contrast-accent); }

.tnum {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  letter-spacing: 0.01em;
}

.figure-mark {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: var(--text-figure);
  line-height: 0.94;
  letter-spacing: -0.02em;
  color: var(--color-primary);
  font-variant-numeric: tabular-nums;
}
.zone-dark .figure-mark { color: var(--color-contrast-accent); }

.keyline {
  text-decoration: underline;
  text-decoration-color: var(--color-accent);
  text-decoration-thickness: 4px;
  text-underline-offset: 4px;
}
.zone-dark .keyline { text-decoration-color: var(--color-contrast-accent); }

/* ---------- 7. 标签 ---------- */
.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 5px 13px;
  border: var(--border-thin) solid var(--color-line);
  border-radius: var(--radius-pill);
  background: var(--color-surface);
  color: var(--color-ink-soft);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.1em;
  text-transform: uppercase;
  line-height: 1.6;
  white-space: nowrap;
}
.tag--primary {
  background: var(--color-primary-soft);
  border-color: var(--color-primary);
  color: var(--color-primary);
}
.tag--accent {
  background: var(--color-highlight);
  border-color: var(--color-accent);
  color: var(--color-accent);
}
.tag--dark {
  background: color-mix(in srgb, var(--color-contrast-ink) 12%, var(--color-contrast-surface));
  border-color: var(--color-contrast-line);
  color: var(--color-contrast-ink);
}
.tag--onDark {
  background: transparent;
  border-color: var(--color-contrast-accent);
  color: var(--color-contrast-accent);
}

/* ---------- 8. 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-1);
  padding: 13px 26px;
  border: var(--border-thin) solid transparent;
  border-radius: var(--radius-pill);
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: var(--text-sm);
  line-height: 1.2;
  letter-spacing: 0.01em;
  cursor: pointer;
  transition: background-color 0.18s ease, color 0.18s ease, border-color 0.18s ease;
}
.btn--primary {
  background: var(--color-primary);
  color: var(--color-primary-ink);
}
.btn--primary:hover { background: var(--color-contrast-surface); color: var(--color-contrast-ink); }
.btn--accent {
  background: var(--color-accent);
  color: var(--color-accent-ink);
}
.btn--accent:hover { background: var(--color-contrast-surface); color: var(--color-contrast-ink); }
.btn--ghost {
  border-color: var(--color-ink);
  color: var(--color-ink);
}
.btn--ghost:hover { background: var(--color-contrast-surface); color: var(--color-contrast-ink); border-color: var(--color-contrast-surface); }
.btn--on-dark {
  border-color: var(--color-contrast-line);
  color: var(--color-contrast-ink);
}
.btn--on-dark:hover {
  background: var(--color-contrast-ink);
  color: var(--color-contrast-surface);
  border-color: var(--color-contrast-ink);
}

/* ---------- 9. 面包屑 ---------- */
.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  color: var(--color-ink-muted);
}
.breadcrumb li {
  display: flex;
  align-items: center;
  gap: 10px;
}
.breadcrumb li + li::before {
  content: "/";
  color: var(--color-line);
}
.breadcrumb a {
  color: var(--color-ink-soft);
  border-bottom: 2px solid transparent;
  transition: color 0.18s ease, border-color 0.18s ease;
}
.breadcrumb a:hover {
  color: var(--color-accent);
  border-bottom-color: var(--color-accent);
}
.breadcrumb [aria-current="page"] { color: var(--color-ink); }

/* ---------- 10. 折叠组 ---------- */
.accordion {
  border-top: var(--border-thin) solid var(--color-ink);
}
.accordion__item {
  border-bottom: var(--border-thin) dotted var(--color-line);
}
.accordion__item > summary {
  display: flex;
  align-items: baseline;
  gap: var(--space-2);
  padding: var(--space-3) 0;
  cursor: pointer;
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: var(--text-lg);
  line-height: var(--leading-heading);
  color: var(--color-ink);
}
.accordion__item > summary:hover { color: var(--color-accent); }
.accordion__marker {
  flex: 0 0 auto;
  width: 11px;
  height: 11px;
  background: var(--color-primary);
  transform: translateY(-3px);
  transition: background-color 0.18s ease, border-radius 0.18s ease;
}
.accordion__item[open] .accordion__marker {
  background: var(--color-accent);
  border-radius: 50%;
}
.accordion__body {
  padding: 0 0 var(--space-4) calc(11px + var(--space-2));
  font-size: var(--text-base);
  line-height: var(--leading-body);
  color: var(--color-ink-soft);
  max-width: var(--measure);
}
.accordion__body > * + * { margin-top: var(--space-2); }
.zone-dark .accordion { border-top-color: var(--color-contrast-line); }
.zone-dark .accordion__item { border-bottom-color: var(--color-contrast-line); }
.zone-dark .accordion__item > summary { color: var(--color-contrast-ink); }
.zone-dark .accordion__marker { background: var(--color-contrast-accent); }
.zone-dark .accordion__body { color: color-mix(in srgb, var(--color-contrast-ink) 76%, var(--color-contrast-surface)); }

/* ---------- 11. 对照表 ---------- */
.matrix {
  width: 100%;
  font-size: var(--text-sm);
  line-height: 1.6;
}
.matrix th,
.matrix td {
  text-align: left;
  padding: 13px var(--space-2);
  border-bottom: var(--border-thin) dotted var(--color-line);
  vertical-align: top;
}
.matrix th {
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: var(--text-sm);
  background: var(--color-surface-alt);
  color: var(--color-ink);
  border-bottom: var(--border-thin) solid var(--color-ink);
  white-space: nowrap;
}
.matrix td:first-child,
.matrix th:first-child { border-left: 4px solid transparent; }
.matrix tbody tr:hover td { background: var(--color-primary-soft); }
.matrix tbody tr.is-selected td { background: var(--color-highlight); }
.matrix tbody tr.is-selected td:first-child { border-left-color: var(--color-accent); }
.matrix .tnum { font-family: var(--font-mono); font-variant-numeric: tabular-nums; }

/* ---------- 12. 图片容器 ---------- */
.media {
  position: relative;
  display: block;
  overflow: hidden;
  margin: 0;
  border-radius: var(--radius-md);
  background: var(--color-surface-deep);
}
.media > img,
.media > picture > img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}
.media--4x3 { aspect-ratio: 4 / 3; }
.media--3x2 { aspect-ratio: 3 / 2; }
.media--1x1 { aspect-ratio: 1 / 1; }
.media--16x9 { aspect-ratio: 16 / 9; }
.media__scrim {
  position: absolute;
  inset: 0;
  background: var(--overlay-scrim);
  pointer-events: none;
}
.media__caption {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 1;
  padding: var(--space-3);
  font-size: var(--text-sm);
  line-height: 1.5;
  color: var(--color-contrast-ink);
}
.media__caption .tnum { color: var(--color-contrast-accent); }

/* ---------- 13. 头部 ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: var(--color-surface);
  border-bottom: var(--border-thick) solid var(--color-ink);
}
.site-header__inner {
  position: relative;
  display: flex;
  align-items: center;
  gap: var(--space-4);
  max-width: var(--container);
  min-height: 76px;
  margin-inline: auto;
  padding: 8px var(--gutter);
}

.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  flex: 0 0 auto;
  min-width: 0;
  padding: 6px 0;
}
.brand__mark {
  position: relative;
  flex: 0 0 auto;
  width: 38px;
  height: 38px;
  border-radius: 50%;
  background: var(--color-primary);
  overflow: hidden;
}
.brand__mark::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  width: 50%;
  height: 100%;
  background: var(--color-highlight);
}
.brand__mark::after {
  content: "";
  position: absolute;
  right: 4px;
  bottom: 4px;
  width: 9px;
  height: 9px;
  background: var(--color-contrast-surface);
}
.brand__text {
  display: flex;
  flex-direction: column;
  gap: 1px;
  min-width: 0;
}
.brand__name {
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--text-lg);
  line-height: 1.05;
  letter-spacing: var(--tracking-heading);
  color: var(--color-ink);
}
.brand__line {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.11em;
  text-transform: uppercase;
  color: var(--color-ink-muted);
  white-space: nowrap;
}

.nav-toggle {
  display: none;
  align-items: center;
  gap: 10px;
  margin-left: auto;
  padding: 10px 18px;
  border: var(--border-thin) solid var(--color-ink);
  border-radius: var(--radius-pill);
  background: var(--color-surface);
  color: var(--color-ink);
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: var(--text-sm);
  cursor: pointer;
  transition: background-color 0.18s ease, color 0.18s ease;
}
.nav-toggle:hover { background: var(--color-contrast-surface); color: var(--color-contrast-ink); }
.nav-toggle__bars {
  display: grid;
  gap: 3px;
  width: 16px;
}
.nav-toggle__bars span {
  display: block;
  height: 2px;
  background: currentColor;
  transition: transform 0.18s ease, opacity 0.18s ease;
}
.nav-toggle[aria-expanded="true"] { background: var(--color-focus); border-color: var(--color-focus); color: var(--color-accent-ink); }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars span:nth-child(1) { transform: translateY(5px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars span:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars span:nth-child(3) { transform: translateY(-5px) rotate(-45deg); }

.site-nav { margin-left: auto; }
.site-nav__list {
  display: flex;
  align-items: center;
  gap: 2px;
}
.site-nav__link {
  position: relative;
  display: flex;
  align-items: baseline;
  gap: 7px;
  padding: 11px 14px 13px;
  border-radius: var(--radius-pill);
  color: var(--color-ink-soft);
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: var(--text-sm);
  line-height: 1.2;
  white-space: nowrap;
  transition: color 0.18s ease, background-color 0.18s ease;
}
.site-nav__link::after {
  content: "";
  position: absolute;
  left: 14px;
  right: 14px;
  bottom: 7px;
  height: 3px;
  background: var(--color-accent);
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform 0.2s ease;
}
.site-nav__link:hover {
  color: var(--color-ink);
  background: var(--color-primary-soft);
}
.site-nav__link:hover::after { transform: scaleX(1); }
.site-nav__index {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  font-weight: 400;
  letter-spacing: 0.08em;
  color: var(--color-ink-muted);
}
.site-nav__label { display: inline-block; }
.site-nav__link[aria-current="page"] {
  color: var(--color-ink);
  background: var(--color-primary-soft);
}
.site-nav__link[aria-current="page"]::after { transform: scaleX(1); }
.site-nav__link[aria-current="page"] .site-nav__index { color: var(--color-focus); }

/* ---------- 14. 页脚 ---------- */
.site-footer {
  position: relative;
  background: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  margin-top: var(--section-y);
}
.site-footer::before {
  content: "";
  display: block;
  height: 10px;
  background-image: radial-gradient(circle, var(--color-contrast-line) 1.6px, transparent 1.7px);
  background-size: 13px 10px;
  background-position: left center;
  background-repeat: repeat-x;
}
.site-footer__inner {
  max-width: var(--container);
  margin-inline: auto;
  padding: var(--space-8) var(--gutter) var(--space-4);
}
.site-footer__grid {
  display: grid;
  grid-template-columns: 1.1fr 1fr 0.8fr 1.3fr;
  gap: var(--space-6) var(--space-4);
  padding-bottom: var(--space-6);
  border-bottom: var(--border-thin) dotted var(--color-contrast-line);
}
.footer-intro__brand {
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--text-lg);
  line-height: 1.1;
  letter-spacing: var(--tracking-heading);
  color: var(--color-contrast-ink);
  margin-bottom: var(--space-2);
}
.footer-intro__note {
  font-size: var(--text-sm);
  line-height: 1.65;
  color: color-mix(in srgb, var(--color-contrast-ink) 68%, var(--color-contrast-surface));
}
.footer-intro__note + .footer-intro__note { margin-top: var(--space-2); }

.footer-col__title {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: var(--text-xs);
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--color-contrast-accent);
  margin-bottom: var(--space-3);
}
.footer-col__list li + li { margin-top: 10px; }
.footer-col__list a {
  display: inline-block;
  font-size: var(--text-sm);
  color: var(--color-contrast-ink);
  border-bottom: 2px solid transparent;
  transition: color 0.18s ease, border-color 0.18s ease;
}
.footer-col__list a:hover {
  color: var(--color-contrast-accent);
  border-bottom-color: var(--color-contrast-accent);
}
.footer-col__list--contact li {
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  line-height: 1.6;
  color: color-mix(in srgb, var(--color-contrast-ink) 82%, var(--color-contrast-surface));
  overflow-wrap: anywhere;
}
.footer-col__list--contact li:first-child { color: var(--color-contrast-accent); }

.site-footer__base {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  justify-content: space-between;
  gap: var(--space-2) var(--space-4);
  padding-top: var(--space-3);
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  line-height: 1.6;
  color: color-mix(in srgb, var(--color-contrast-ink) 58%, var(--color-contrast-surface));
}
.footer-record,
.footer-copy { margin: 0; }

/* ---------- 15. 回到顶部 & 显现 ---------- */
.to-top {
  position: fixed;
  right: var(--space-3);
  bottom: var(--space-3);
  z-index: 70;
  display: grid;
  place-items: center;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  font-family: var(--font-mono);
  font-size: var(--text-lg);
  line-height: 1;
  cursor: pointer;
  transition: background-color 0.18s ease, color 0.18s ease;
}
.to-top:hover { background: var(--color-accent); color: var(--color-accent-ink); }
.to-top[hidden] { display: none; }

.has-reveal [data-reveal] {
  opacity: 0;
  transform: translateY(14px);
  transition: opacity 0.2s ease, transform 0.2s ease;
}
.has-reveal [data-reveal][data-revealed] {
  opacity: 1;
  transform: none;
}

/* ---------- 16. 响应式 ---------- */
@media (max-width: 1080px) {
  .site-nav__link { padding: 11px 10px 13px; font-size: var(--text-sm); }
  .site-nav__link::after { left: 10px; right: 10px; }
  .site-nav__list { gap: 0; }
}

@media (max-width: 980px) {
  .brand__line { display: none; }
  .nav-toggle { display: inline-flex; }

  .site-nav {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    margin-left: 0;
    display: none;
    padding: var(--space-2) var(--gutter) var(--space-4);
    background: var(--color-surface);
    border-bottom: var(--border-thick) solid var(--color-ink);
    max-height: calc(100vh - 76px);
    overflow-y: auto;
  }
  .site-nav[data-open] { display: block; }
  .site-nav__list {
    flex-direction: column;
    align-items: stretch;
    gap: 0;
  }
  .site-nav__link {
    display: flex;
    align-items: center;
    gap: var(--space-2);
    padding: 15px 12px;
    border-left: 5px solid transparent;
    border-radius: 0;
    font-size: var(--text-base);
  }
  .site-nav__link::after { display: none; }
  .site-nav__link:hover {
    background: var(--color-surface-alt);
    color: var(--color-ink);
  }
  .site-nav__link[aria-current="page"] {
    background: var(--color-primary-soft);
    border-left-color: var(--color-focus);
  }

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

  .grid--3,
  .grid--6 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 640px) {
  .grid--2,
  .grid--3,
  .grid--6 { grid-template-columns: minmax(0, 1fr); }

  .site-header__inner { min-height: 66px; gap: var(--space-2); }
  .site-nav { max-height: calc(100vh - 66px); }

  .section { padding-block: var(--space-8); }
  .section--lg { padding-block: var(--space-8); }

  .site-footer__grid { grid-template-columns: minmax(0, 1fr); }
  .site-footer__inner { padding-top: var(--space-6); }
  .site-footer__base { flex-direction: column; align-items: flex-start; }
}

@media (max-width: 520px) {
  .brand__mark { width: 32px; height: 32px; }
  .brand__name { font-size: var(--text-base); }
  .nav-toggle__text { display: none; }
  .nav-toggle { padding: 10px 14px; }
  .to-top { right: var(--space-2); bottom: var(--space-2); width: 44px; height: 44px; }
}

/* ---------- 17. 减少动效 ---------- */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
    scroll-behavior: auto !important;
  }
  .has-reveal [data-reveal] {
    opacity: 1;
    transform: none;
  }
}