/* ==================================================
   9棋牌 · 四季中文官网 — 全站共享样式 /assets/site.css
   设计语言：四季牌桌 · 深绿绒面 / 鎏金收边 / 纸张叠层
   ================================================== */

/* ---------- 1. 设计变量与 Reset ---------- */
:root {
  --deep-green: #0B3D2E;
  --forest-green: #145C43;
  --moss-green: #2B7A5E;
  --gold: #D4AF37;
  --light-gold: #F2D276;
  --ivory: #F7F2E9;
  --warm-gray: #E8E0D2;
  --ink: #0A0B0A;
  --jade: #3AA899;

  --font-serif: "Noto Serif SC", "Songti SC", "STSong", "SimSun", serif;
  --font-sans: "Noto Sans SC", "Source Han Sans SC", "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", sans-serif;
  --font-mono: "SF Mono", "Cascadia Code", "Consolas", "Liberation Mono", monospace;

  --header-height: 84px;
  --container-max: 1200px;
  --gap: 24px;
  --gap-lg: 48px;
  --radius-sm: 6px;
  --radius-md: 14px;
  --radius-lg: 24px;

  --shadow-soft: 0 8px 28px rgba(3, 15, 11, 0.35);
  --shadow-gold: 0 4px 20px rgba(212, 175, 55, 0.18);
  --transition-fast: 160ms ease;
  --transition: 300ms cubic-bezier(0.22, 0.61, 0.36, 1);

  --text-strong: var(--ivory);
  --text-regular: var(--warm-gray);
  --line-soft: rgba(212, 175, 55, 0.14);
}

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

html {
  scroll-padding-top: calc(var(--header-height) + 16px);
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  min-height: 100vh;
  background: linear-gradient(180deg, #0B3D2E 0%, #0A2D23 45%, #081F18 100%);
  color: var(--text-regular);
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-serif);
  font-weight: 700;
  line-height: 1.25;
  color: var(--text-strong);
  margin: 0 0 0.5em;
}

p, ul, ol, dl, blockquote, figure {
  margin: 0 0 1em;
}

ul[class], ol[class] {
  list-style: none;
  padding-left: 0;
  margin: 0;
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

a {
  color: var(--gold);
  text-decoration-thickness: 1px;
  text-underline-offset: 4px;
  transition: color var(--transition-fast);
}
a:hover {
  color: var(--light-gold);
}

button {
  font: inherit;
}

::selection {
  background: var(--gold);
  color: var(--deep-green);
}

/* ---------- 2. 焦点与无障碍 ---------- */
:focus-visible {
  outline: 3px solid var(--light-gold);
  outline-offset: 3px;
  border-radius: 2px;
}

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

.skip-link {
  position: fixed;
  top: -100px;
  left: 16px;
  z-index: 9999;
  background: var(--gold);
  color: var(--deep-green);
  font-weight: 700;
  padding: 10px 24px;
  border-radius: 0 0 var(--radius-md) var(--radius-md);
  text-decoration: none;
  box-shadow: var(--shadow-soft);
  transition: top var(--transition-fast);
}
.skip-link:focus-visible {
  top: 0;
}

/* ---------- 3. 布局容器 ---------- */
.container {
  width: min(100% - 48px, var(--container-max));
  margin-inline: auto;
}

.site-main {
  min-height: 60vh;
}
#main-content:focus {
  outline: none;
}

.section {
  padding: 104px 0;
}
.section--tight {
  padding: 64px 0;
}
.section--alt {
  background: linear-gradient(180deg, rgba(20, 92, 67, 0.22), rgba(11, 61, 46, 0.02));
  border-block: 1px solid var(--line-soft);
}
.section--light {
  --text-strong: var(--ink);
  --text-regular: #4A4434;
  --line-soft: rgba(11, 61, 46, 0.14);
  background: var(--ivory);
  color: var(--text-regular);
  border-block: 1px solid var(--line-soft);
}
.section--light a {
  color: var(--forest-green);
}
.section--light a:hover {
  color: var(--deep-green);
}

/* ---------- 4. 网格 ---------- */
.grid-2,
.grid-3,
.grid-4 {
  display: grid;
  gap: var(--gap);
}
.grid-2 {
  grid-template-columns: repeat(2, minmax(0, 1fr));
}
.grid-3 {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}
.grid-4 {
  grid-template-columns: repeat(4, minmax(0, 1fr));
}

/* ---------- 5. 页头 ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(11, 61, 46, 0.88);
  -webkit-backdrop-filter: blur(12px);
  backdrop-filter: blur(12px);
  box-shadow: none;
  transition: background var(--transition), box-shadow var(--transition);
}
.site-header.is-scrolled {
  background: rgba(8, 40, 31, 0.97);
  box-shadow: 0 6px 24px rgba(3, 15, 11, 0.45);
}
.site-header::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent 0%, rgba(212, 175, 55, 0.45) 18%, rgba(212, 175, 55, 0.45) 82%, transparent 100%);
  pointer-events: none;
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  height: var(--header-height);
  max-width: 1440px;
  margin-inline: auto;
  padding-inline: clamp(20px, 4vw, 48px);
}

/* 品牌 */
.brand-link {
  display: flex;
  align-items: center;
  gap: 14px;
  flex-shrink: 0;
  text-decoration: none;
  color: var(--ivory);
}
.brand-link:hover {
  color: var(--ivory);
}
.brand-emblem {
  position: relative;
  width: 52px;
  height: 52px;
  border-radius: 50%;
  background: linear-gradient(145deg, var(--gold) 0%, #B8952E 100%);
  color: var(--deep-green);
  font-family: var(--font-serif);
  font-size: 29px;
  font-weight: 900;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: inset 0 -2px 0 rgba(10, 11, 10, 0.18);
  flex-shrink: 0;
}
.brand-emblem::after {
  content: "";
  position: absolute;
  inset: 5px;
  border: 1px solid rgba(11, 61, 46, 0.35);
  border-radius: 50%;
  pointer-events: none;
}
.brand-copy {
  display: flex;
  flex-direction: column;
  line-height: 1.25;
}
.brand-name {
  font-family: var(--font-serif);
  font-size: 23px;
  font-weight: 900;
  letter-spacing: 0.06em;
  white-space: nowrap;
}
.brand-tagline {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--warm-gray);
  white-space: nowrap;
}
.brand-tagline::before {
  content: "";
  width: 6px;
  height: 6px;
  background: var(--gold);
  transform: rotate(45deg);
  flex-shrink: 0;
}

/* 导航 */
.site-nav {
  margin-left: auto;
}
.nav-list {
  display: flex;
  align-items: center;
  gap: 2px;
}
.nav-link {
  position: relative;
  display: block;
  padding: 10px 16px;
  color: var(--ivory);
  font-size: 15px;
  font-weight: 500;
  letter-spacing: 0.1em;
  text-decoration: none;
  transition: color var(--transition-fast);
}
.nav-link::after {
  content: "";
  position: absolute;
  left: 50%;
  bottom: 4px;
  width: 20px;
  height: 2px;
  border-radius: 2px;
  background: var(--gold);
  transform: translateX(-50%) scaleX(0);
  transform-origin: center;
  transition: transform var(--transition-fast);
}
.nav-link:hover {
  color: var(--light-gold);
}
.nav-link:hover::after,
.nav-link[aria-current="page"]::after {
  transform: translateX(-50%) scaleX(1);
}
.nav-link[aria-current="page"] {
  color: var(--gold);
}

/* 移动导航按钮 */
.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 5px;
  width: 44px;
  height: 44px;
  padding: 0;
  background: transparent;
  border: 1px solid rgba(212, 175, 55, 0.4);
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: border-color var(--transition-fast), background var(--transition-fast);
}
.nav-toggle:hover {
  border-color: var(--gold);
  background: rgba(212, 175, 55, 0.08);
}
.nav-toggle-line {
  width: 20px;
  height: 2px;
  border-radius: 2px;
  background: var(--gold);
  transition: transform var(--transition-fast), opacity var(--transition-fast);
}
.nav-toggle.is-active .nav-toggle-line:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}
.nav-toggle.is-active .nav-toggle-line:nth-child(2) {
  opacity: 0;
}
.nav-toggle.is-active .nav-toggle-line:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* ---------- 6. 页脚 ---------- */
.site-footer {
  position: relative;
  margin-top: 96px;
  background: linear-gradient(180deg, #071F18 0%, #041410 100%);
  border-top: 1px solid rgba(212, 175, 55, 0.28);
  color: var(--warm-gray);
  overflow: hidden;
}
.site-footer::before {
  content: "季";
  position: absolute;
  right: 3%;
  bottom: -14%;
  font-family: var(--font-serif);
  font-size: clamp(160px, 26vw, 340px);
  line-height: 1;
  color: rgba(43, 122, 94, 0.07);
  pointer-events: none;
  user-select: none;
}

.footer-inner {
  position: relative;
  z-index: 1;
  width: min(100% - 48px, var(--container-max));
  margin-inline: auto;
  padding: 72px 0 32px;
}

.footer-top {
  display: grid;
  grid-template-columns: minmax(260px, 1.4fr) 0.7fr 0.7fr 1.1fr;
  gap: var(--gap-lg);
  padding-bottom: 56px;
  border-bottom: 1px solid rgba(212, 175, 55, 0.14);
}

.footer-brand-link {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-bottom: 18px;
  color: var(--ivory);
  text-decoration: none;
}
.footer-brand-link:hover {
  color: var(--ivory);
}
.footer-brand-badge {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: linear-gradient(145deg, var(--gold) 0%, #B8952E 100%);
  color: var(--deep-green);
  font-family: var(--font-serif);
  font-size: 25px;
  font-weight: 900;
  flex-shrink: 0;
  box-shadow: inset 0 -2px 0 rgba(10, 11, 10, 0.18);
}
.footer-brand-name {
  display: block;
  font-family: var(--font-serif);
  font-size: 21px;
  font-weight: 700;
  letter-spacing: 0.06em;
  line-height: 1.3;
}
.footer-brand-tag {
  display: block;
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--warm-gray);
}

.footer-desc {
  max-width: 340px;
  font-size: 14px;
  line-height: 1.85;
  color: var(--warm-gray);
}

.season-dots {
  display: inline-flex;
  gap: 8px;
  margin-top: 16px;
}
.season-dot {
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--gold);
}
.season-dot--spring {
  background: var(--jade);
}
.season-dot--summer {
  background: var(--moss-green);
}
.season-dot--autumn {
  background: var(--gold);
}
.season-dot--winter {
  background: var(--warm-gray);
}

.footer-heading {
  margin-bottom: 18px;
  padding-bottom: 8px;
  border-bottom: 1px solid rgba(212, 175, 55, 0.16);
  color: var(--gold);
  font-family: var(--font-serif);
  font-size: 16px;
  font-weight: 700;
  letter-spacing: 0.1em;
}

.footer-list a {
  color: var(--warm-gray);
  font-size: 14px;
  text-decoration: none;
  transition: color var(--transition-fast), padding-left var(--transition-fast);
}
.footer-list a:hover {
  color: var(--light-gold);
  padding-left: 6px;
}
.footer-list li + li {
  margin-top: 8px;
}

.footer-contact-list {
  font-size: 14px;
  line-height: 1.9;
}
.footer-contact-list li {
  position: relative;
  padding-left: 18px;
}
.footer-contact-list li::before {
  content: "";
  position: absolute;
  left: 1px;
  top: 0.9em;
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background: var(--moss-green);
}
.footer-contact-list strong {
  color: var(--ivory);
  font-weight: 600;
}

.footer-bottom {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  align-items: center;
  gap: 10px 28px;
  padding-top: 24px;
  font-size: 13px;
  color: rgba(232, 224, 210, 0.58);
}
.footer-bottom p {
  margin: 0;
}
.legal-sep {
  display: inline-block;
  margin: 0 8px;
  color: var(--gold);
}

/* 返回顶部 */
.back-top {
  position: fixed;
  right: 28px;
  bottom: 28px;
  z-index: 90;
  width: 52px;
  height: 52px;
  border: none;
  border-radius: 50%;
  background: linear-gradient(145deg, var(--gold) 0%, #B8952E 100%);
  color: var(--deep-green);
  font-size: 22px;
  font-weight: 700;
  line-height: 1;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: var(--shadow-gold);
  opacity: 0;
  visibility: hidden;
  transform: translateY(16px) scale(0.92);
  transition: transform var(--transition), opacity var(--transition), visibility 0s linear 300ms;
}
.back-top.is-visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0) scale(1);
  transition: transform var(--transition), opacity var(--transition);
}
.back-top:hover {
  background: var(--light-gold);
}

/* ---------- 7. 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 13px 30px;
  border: 2px solid transparent;
  border-radius: 999px;
  font-family: var(--font-sans);
  font-size: 16px;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-decoration: none;
  cursor: pointer;
  transition: background var(--transition-fast), border-color var(--transition-fast), color var(--transition-fast), transform var(--transition-fast), box-shadow var(--transition-fast);
}
.btn-primary {
  background: var(--gold);
  color: var(--deep-green);
}
.btn-primary:hover {
  background: var(--light-gold);
  color: var(--deep-green);
  transform: translateY(-2px);
  box-shadow: var(--shadow-gold);
}
.btn-ghost {
  background: transparent;
  color: var(--gold);
  border-color: var(--gold);
}
.btn-ghost:hover {
  background: rgba(212, 175, 55, 0.12);
  border-color: var(--light-gold);
  color: var(--light-gold);
  transform: translateY(-2px);
}
.btn-lg {
  padding: 17px 42px;
  font-size: 18px;
}

/* ---------- 8. 面包屑 ---------- */
.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
  margin: 24px 0 8px;
  padding: 0;
  list-style: none;
  font-size: 14px;
  color: var(--text-regular);
}
.breadcrumb li + li::before {
  content: "·";
  margin-right: 10px;
  color: var(--gold);
}
.breadcrumb a {
  color: inherit;
  text-decoration: none;
  transition: color var(--transition-fast);
}
.breadcrumb a:hover {
  color: var(--light-gold);
}
.breadcrumb [aria-current="page"] {
  color: var(--gold);
}
.section--light .breadcrumb [aria-current="page"] {
  color: var(--forest-green);
}

/* ---------- 9. 章节标题 ---------- */
.section-heading {
  max-width: 760px;
  margin-bottom: 48px;
}
.section-eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 10px;
  color: var(--gold);
  font-size: 14px;
  font-weight: 600;
  letter-spacing: 0.16em;
}
.section-eyebrow::before {
  content: "";
  display: inline-block;
  width: 28px;
  height: 1px;
  background: linear-gradient(90deg, var(--gold), transparent);
}
.section--light .section-eyebrow {
  color: var(--forest-green);
}
.section--light .section-eyebrow::before {
  background: linear-gradient(90deg, var(--forest-green), transparent);
}
.section-title {
  font-family: var(--font-serif);
  font-size: clamp(32px, 4.6vw, 52px);
  line-height: 1.2;
  color: var(--text-strong);
  margin: 0 0 12px;
}
.section-title em {
  font-style: normal;
  color: var(--gold);
}
.section--light .section-title em {
  color: var(--forest-green);
}
.section-lead {
  max-width: 640px;
  margin-top: 14px;
  color: var(--text-regular);
  font-size: 17px;
}

/* ---------- 10. 正文容器 ---------- */
.text-block {
  max-width: 720px;
  color: var(--text-regular);
  font-size: 16px;
  line-height: 1.85;
}
.text-block > * + * {
  margin-top: 16px;
}
.text-block h2 {
  font-size: 28px;
  color: var(--text-strong);
}
.text-block h3 {
  font-size: 21px;
  color: var(--text-strong);
}
.text-block a {
  color: var(--gold);
}
.section--light .text-block a {
  color: var(--forest-green);
}
.text-block ul,
.text-block ol {
  padding-left: 1.4em;
}
.text-block blockquote {
  margin: 24px 0;
  padding: 16px 24px;
  border-left: 3px solid var(--gold);
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  background: rgba(212, 175, 55, 0.08);
  color: var(--text-strong);
}
.text-block code {
  padding: 2px 8px;
  border-radius: 4px;
  background: rgba(242, 210, 118, 0.1);
  font-family: var(--font-mono);
  font-size: 0.9em;
}

/* ---------- 11. 卡片 ---------- */
.card {
  position: relative;
  padding: 32px;
  border: 1px solid var(--moss-green);
  border-radius: var(--radius-lg);
  background: linear-gradient(160deg, rgba(20, 92, 67, 0.55) 0%, rgba(11, 61, 46, 0.92) 100%);
  box-shadow: var(--shadow-soft);
  transition: transform var(--transition), border-color var(--transition), box-shadow var(--transition);
}
.card::before {
  content: "";
  position: absolute;
  inset: 10px;
  border: 1px solid rgba(212, 175, 55, 0.09);
  border-radius: calc(var(--radius-lg) - 8px);
  pointer-events: none;
}
.card:hover {
  transform: translateY(-4px);
  border-color: rgba(212, 175, 55, 0.55);
  box-shadow: 0 16px 36px rgba(3, 15, 11, 0.42);
}

/* ---------- 12. 标签 ---------- */
.tag {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  padding: 5px 14px;
  border: 1px solid rgba(212, 175, 55, 0.35);
  border-radius: 999px;
  background: rgba(212, 175, 55, 0.1);
  color: var(--light-gold);
  font-size: 13px;
  letter-spacing: 0.06em;
  white-space: nowrap;
}
.tag::before {
  content: "";
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background: currentColor;
  flex-shrink: 0;
}
.tag--jade {
  border-color: rgba(58, 168, 153, 0.35);
  background: rgba(58, 168, 153, 0.1);
  color: var(--jade);
}

/* ---------- 13. 图片容器基础 ---------- */
.figure {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 200px;
  overflow: hidden;
  border: 1px solid rgba(43, 122, 94, 0.45);
  border-radius: var(--radius-lg);
  background:
    radial-gradient(circle at 72% 28%, rgba(212, 175, 55, 0.12) 0%, transparent 46%),
    linear-gradient(145deg, rgba(43, 122, 94, 0.36), rgba(11, 61, 46, 0.88));
}
.figure::before {
  content: attr(data-placeholder);
  padding: 8px 18px;
  border: 1px dashed rgba(212, 175, 55, 0.4);
  border-radius: 999px;
  background: rgba(11, 61, 46, 0.35);
  color: var(--warm-gray);
  font-size: 14px;
  letter-spacing: 0.18em;
}
.figure:not([data-placeholder])::before {
  display: none;
}
.figure img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
}
.figure--ratio-4-3 {
  aspect-ratio: 4 / 3;
}
.figure--ratio-1-1 {
  aspect-ratio: 1 / 1;
}
.figure--ratio-21-9 {
  aspect-ratio: 21 / 9;
}

/* ---------- 14. 滚动显现 ---------- */
.js [data-reveal] {
  opacity: 0;
  transform: translateY(28px);
  transition:
    opacity 520ms cubic-bezier(0.22, 0.61, 0.36, 1),
    transform 520ms cubic-bezier(0.22, 0.61, 0.36, 1);
}
.js [data-reveal].is-visible {
  opacity: 1;
  transform: translateY(0);
}

/* ---------- 15. 响应式 ---------- */
@media (max-width: 1024px) {
  :root {
    --gap-lg: 36px;
  }
  .grid-4 {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
  .footer-top {
    grid-template-columns: 1fr 1fr;
    gap: 40px;
  }
}

@media (max-width: 900px) {
  :root {
    --header-height: 68px;
  }
  .grid-3 {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .nav-toggle {
    display: flex;
  }

  .site-nav {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    z-index: 1;
    margin-left: 0;
    padding: 16px 24px 24px;
    background: linear-gradient(180deg, #0D4433 0%, #0A2D23 100%);
    box-shadow: var(--shadow-soft);
    transform: translateY(-12px);
    opacity: 0;
    visibility: hidden;
    transition:
      transform 300ms cubic-bezier(0.22, 0.61, 0.36, 1),
      opacity 300ms cubic-bezier(0.22, 0.61, 0.36, 1),
      visibility 0s linear 300ms;
  }
  .site-nav[data-open] {
    transform: translateY(0);
    opacity: 1;
    visibility: visible;
    transition:
      transform 300ms cubic-bezier(0.22, 0.61, 0.36, 1),
      opacity 300ms cubic-bezier(0.22, 0.61, 0.36, 1);
  }

  .nav-list {
    flex-direction: column;
    align-items: stretch;
    gap: 0;
  }
  .nav-item + .nav-item {
    border-top: 1px solid rgba(212, 175, 55, 0.12);
  }
  .nav-link {
    padding: 15px 8px;
    font-size: 17px;
    text-align: left;
  }
  .nav-link::after {
    left: 0;
    bottom: auto;
    top: 50%;
    width: 2px;
    height: 20px;
    transform: translateY(-50%) scaleY(0);
  }
  .nav-link:hover::after,
  .nav-link[aria-current="page"]::after {
    transform: translateY(-50%) scaleY(1);
  }
}

@media (max-width: 640px) {
  :root {
    --gap: 16px;
  }
  .container {
    width: min(100% - 32px, var(--container-max));
  }
  .section {
    padding: 64px 0;
  }
  .section--tight {
    padding: 40px 0;
  }
  .grid-2,
  .grid-3,
  .grid-4 {
    grid-template-columns: minmax(0, 1fr);
  }
  .footer-inner {
    width: min(100% - 32px, var(--container-max));
  }
  .footer-top {
    grid-template-columns: 1fr;
    gap: 32px;
  }
  .footer-bottom {
    flex-direction: column;
    align-items: flex-start;
  }
  .back-top {
    right: 20px;
    bottom: 20px;
  }
}

/* ---------- 16. 减少动效偏好 ---------- */
@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    transition-delay: 0s !important;
  }
  .js [data-reveal] {
    opacity: 1 !important;
    transform: none !important;
    transition: none !important;
  }
  .back-top,
  .site-header,
  .site-nav,
  .nav-toggle {
    transition: none !important;
  }
}