/* ============================================================
   币游主站 · 共享站点样式 /assets/site.css
   ============================================================ */

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

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

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

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

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

img { height: auto; }

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

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

a { color: inherit; }

table { width: 100%; border-collapse: collapse; }

[hidden] { display: none !important; }

::selection {
  background: var(--c-sandgold);
  color: var(--c-night);
}

/* ---------- 2. 变量 ---------- */
:root {
  /* 色彩 · 丹霞与绿洲 */
  --c-danxia:     #A33A2B;
  --c-sandgold:   #D9A441;
  --c-dusk:       #473A66;
  --c-turquoise:  #1FA6A0;
  --c-teal:       #0E2F33;
  --c-sand:       #F6EFE2;
  --c-sand-deep:  #EFE4D1;
  --c-terracotta: #C96B3B;
  --c-rock:       #6B6A66;
  --c-night:      #1C1A17;
  --c-paleturq:   #B8E3DF;

  --c-sand-72: rgba(246, 239, 226, 0.72);
  --c-sand-54: rgba(246, 239, 226, 0.54);
  --c-sand-16: rgba(246, 239, 226, 0.16);
  --c-sand-08: rgba(246, 239, 226, 0.08);
  --c-teal-72: rgba(14, 47, 51, 0.72);
  --c-teal-28: rgba(14, 47, 51, 0.28);
  --c-teal-08: rgba(14, 47, 51, 0.06);

  /* 字体 */
  --f-display: "Noto Serif SC", "Source Han Serif SC", "Songti SC", "SimSun", Georgia, serif;
  --f-body: "Noto Sans SC", "HarmonyOS Sans SC", "PingFang SC", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  --f-mono: "JetBrains Mono", "IBM Plex Mono", "Roboto Mono", ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;

  /* 尺度 */
  --w-shell: 1200px;
  --w-narrow: 760px;
  --w-wide: 1440px;
  --gutter: clamp(1.25rem, 4vw, 3.5rem);
  --radius-s: 8px;
  --radius-m: 16px;
  --radius-l: 30px;
  --radius-pill: 999px;

  /* 节奏 */
  --space-1: 0.5rem;
  --space-2: 1rem;
  --space-3: 1.75rem;
  --space-4: 3rem;
  --space-5: clamp(3.5rem, 9vw, 7rem);
  --space-6: clamp(4.5rem, 12vw, 9rem);

  /* 动效 */
  --ease-soft: cubic-bezier(0.22, 0.61, 0.36, 1);
  --dur-fast: 160ms;
  --dur-mid: 320ms;

  --shadow-soft: 0 26px 60px -36px rgba(14, 47, 51, 0.6);
}

/* ---------- 3. 基础排版 ---------- */
body {
  background-color: var(--c-sand);
  color: var(--c-teal);
  font-family: var(--f-body);
  font-size: 1.0625rem;
  font-weight: 400;
  line-height: 1.8;
  letter-spacing: 0.01em;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
}

h1, h2, h3, h4, h5, h6 {
  font-family: var(--f-display);
  font-weight: 900;
  line-height: 1.16;
  letter-spacing: -0.01em;
  color: var(--c-night);
}

h1 { font-size: clamp(2.5rem, 6vw, 4.5rem); }
h2 { font-size: clamp(1.75rem, 3.6vw, 2.75rem); }
h3 { font-size: clamp(1.25rem, 2.2vw, 1.75rem); }
h4 { font-size: 1.125rem; font-weight: 700; }

p { text-wrap: pretty; }

strong { font-weight: 700; color: var(--c-night); }

small { font-size: 0.8125rem; }

code, kbd, samp {
  font-family: var(--f-mono);
  font-size: 0.9em;
}

hr {
  border: 0;
  height: 1px;
  background: var(--c-teal-28);
  margin-block: var(--space-3);
}

#main-content { display: block; scroll-margin-top: 88px; }

/* ---------- 4. 布局骨架 ---------- */
.shell {
  width: min(var(--w-shell), calc(100% - var(--gutter) * 2));
  margin-inline: auto;
}

.shell--narrow {
  width: min(var(--w-narrow), calc(100% - var(--gutter) * 2));
  margin-inline: auto;
}

.shell--wide {
  width: min(var(--w-wide), calc(100% - var(--gutter) * 2));
  margin-inline: auto;
}

.section { padding-block: var(--space-5); }
.section--tight { padding-block: var(--space-4); }
.section--loose { padding-block: var(--space-6); }

.section--dusk {
  background: var(--c-dusk);
  color: var(--c-sand-72);
}
.section--dusk h1,
.section--dusk h2,
.section--dusk h3,
.section--dusk h4 { color: var(--c-sand); }

.section--teal {
  background: var(--c-teal);
  color: var(--c-sand-72);
}
.section--teal h1,
.section--teal h2,
.section--teal h3,
.section--teal h4 { color: var(--c-sand); }

.section--sand { background: var(--c-sand-deep); }

.grid {
  display: grid;
  gap: clamp(1.25rem, 3vw, 2.25rem);
}
.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. 头部 · 紧凑命令栏 ---------- */
.skip-link {
  position: absolute;
  left: 1rem;
  top: -140%;
  z-index: 200;
  padding: 0.75rem 1.35rem;
  background: var(--c-sandgold);
  color: var(--c-night);
  font-size: 0.875rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-decoration: none;
  border-radius: 0 0 var(--radius-m) var(--radius-m);
  transition: top var(--dur-fast) var(--ease-soft);
}
.skip-link:focus { top: 0; }

.site-header {
  position: sticky;
  top: 0;
  z-index: 70;
  background: var(--c-teal);
  color: var(--c-sand);
  border-bottom: 1px solid var(--c-sand-16);
  transition: border-color var(--dur-mid) var(--ease-soft),
              box-shadow var(--dur-mid) var(--ease-soft);
}

.site-header[data-scrolled] {
  border-bottom-color: rgba(217, 164, 65, 0.5);
  box-shadow: 0 20px 44px -34px rgba(0, 0, 0, 0.95);
}

.site-header__inner {
  position: relative;
  width: min(var(--w-shell), calc(100% - var(--gutter) * 2));
  margin-inline: auto;
  min-height: 70px;
  display: flex;
  align-items: center;
  gap: clamp(0.75rem, 2vw, 1.75rem);
}

.site-header__progress {
  position: absolute;
  left: 0;
  right: 0;
  bottom: -1px;
  height: 2px;
  transform: scaleX(0);
  transform-origin: 0 50%;
  background: linear-gradient(90deg, var(--c-danxia), var(--c-sandgold) 52%, var(--c-turquoise));
  pointer-events: none;
}

.brand {
  flex: 0 0 auto;
  display: inline-flex;
  align-items: center;
  gap: 0.65rem;
  padding-block: 0.35rem;
  color: var(--c-sand);
  text-decoration: none;
}

.brand__mark {
  inline-size: 36px;
  block-size: 36px;
  display: grid;
  place-items: center;
  font-family: var(--f-display);
  font-size: 1.05rem;
  font-weight: 900;
  color: var(--c-night);
  background: linear-gradient(150deg, var(--c-sandgold) 0%, var(--c-danxia) 78%);
  border-radius: 58% 42% 46% 54% / 52% 48% 52% 48%;
  transition: border-radius var(--dur-mid) var(--ease-soft);
}
.brand:hover .brand__mark {
  border-radius: 42% 58% 54% 46% / 48% 52% 48% 52%;
}

.brand__text {
  display: grid;
  line-height: 1.2;
}

.brand__name {
  font-family: var(--f-display);
  font-size: 1.0625rem;
  font-weight: 700;
  letter-spacing: 0.05em;
}

.brand__tag {
  font-family: var(--f-mono);
  font-size: 0.625rem;
  letter-spacing: 0.22em;
  color: var(--c-sand-54);
}

.nav-toggle {
  display: none;
  align-items: center;
  gap: 0.5rem;
  margin-inline-start: auto;
  padding: 0.45rem 0.8rem;
  border: 1px solid var(--c-sand-16);
  border-radius: var(--radius-pill);
  color: var(--c-sand);
  font-size: 0.75rem;
  letter-spacing: 0.16em;
  transition: border-color var(--dur-fast) var(--ease-soft),
              background-color var(--dur-fast) var(--ease-soft);
}
.nav-toggle:hover { border-color: var(--c-sand-54); }
.nav-toggle[data-active] {
  border-color: var(--c-turquoise);
  background: rgba(31, 166, 160, 0.18);
}

.nav-toggle__label { letter-spacing: 0.16em; }

.nav-toggle__bars,
.nav-toggle__bars::before,
.nav-toggle__bars::after {
  display: block;
  inline-size: 18px;
  block-size: 2px;
  border-radius: 2px;
  background: currentColor;
  transition: transform var(--dur-mid) var(--ease-soft),
              opacity var(--dur-fast) linear,
              background-color var(--dur-fast) linear;
}
.nav-toggle__bars { position: relative; }
.nav-toggle__bars::before,
.nav-toggle__bars::after {
  content: "";
  position: absolute;
  left: 0;
}
.nav-toggle__bars::before { top: -6px; }
.nav-toggle__bars::after { top: 6px; }

.nav-toggle[data-active] .nav-toggle__bars { background: transparent; }
.nav-toggle[data-active] .nav-toggle__bars::before { transform: translateY(6px) rotate(45deg); }
.nav-toggle[data-active] .nav-toggle__bars::after { transform: translateY(-6px) rotate(-45deg); }

.site-nav { margin-inline-start: auto; }

.site-nav__list {
  display: flex;
  align-items: center;
  gap: clamp(0.25rem, 1.4vw, 1.1rem);
}

.site-nav__link {
  position: relative;
  display: block;
  padding: 0.45rem 0.55rem;
  font-size: 0.875rem;
  letter-spacing: 0.08em;
  white-space: nowrap;
  color: var(--c-sand-72);
  text-decoration: none;
  transition: color var(--dur-fast) var(--ease-soft);
}

.site-nav__link::after {
  content: "";
  position: absolute;
  left: 0.55rem;
  right: 0.55rem;
  bottom: 0.2rem;
  height: 2px;
  background: var(--c-turquoise);
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform var(--dur-mid) var(--ease-soft),
              background-color var(--dur-fast) var(--ease-soft);
}

.site-nav__link:hover { color: var(--c-sand); }
.site-nav__link:hover::after { transform: scaleX(0.55); }

.site-nav__link[aria-current="page"] {
  color: var(--c-sandgold);
  font-weight: 700;
}
.site-nav__link[aria-current="page"]::after {
  transform: scaleX(1);
  background: var(--c-sandgold);
}

.header-actions {
  flex: 0 0 auto;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.header-cta {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  padding: 0.45rem 0.9rem;
  font-size: 0.8125rem;
  letter-spacing: 0.06em;
  text-decoration: none;
  border: 1px solid var(--c-sand-16);
  border-radius: var(--radius-pill);
  color: var(--c-sand-72);
  transition: color var(--dur-fast) var(--ease-soft),
              border-color var(--dur-fast) var(--ease-soft),
              background-color var(--dur-fast) var(--ease-soft);
}
.header-cta:hover { color: var(--c-sand); border-color: var(--c-sand-54); }

.header-cta--solid {
  background: var(--c-turquoise);
  border-color: var(--c-turquoise);
  color: var(--c-night);
  font-weight: 700;
}
.header-cta--solid:hover {
  background: var(--c-paleturq);
  border-color: var(--c-paleturq);
  color: var(--c-night);
}

/* ---------- 6. 页脚 · 暮紫驿站 ---------- */
.site-footer {
  position: relative;
  margin-top: clamp(3.5rem, 10vw, 8rem);
  background: var(--c-dusk);
  color: var(--c-sand-72);
  overflow: hidden;
}

.site-footer::before {
  content: "";
  position: absolute;
  inset-inline: 0;
  top: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--c-danxia), var(--c-sandgold) 48%, var(--c-turquoise));
}

.site-footer::after {
  content: "";
  position: absolute;
  right: -16%;
  top: -28%;
  inline-size: min(560px, 72vw);
  aspect-ratio: 1 / 1;
  border-radius: 46% 54% 38% 62% / 58% 42% 58% 42%;
  background: radial-gradient(circle at 32% 30%, rgba(201, 107, 59, 0.32), transparent 68%);
  pointer-events: none;
}

.site-footer__inner {
  position: relative;
  z-index: 1;
  width: min(var(--w-shell), calc(100% - var(--gutter) * 2));
  margin-inline: auto;
  padding-block: clamp(3rem, 7vw, 5rem) clamp(2rem, 4vw, 3rem);
  display: grid;
  grid-template-columns: minmax(0, 1.5fr) minmax(0, 1fr) minmax(0, 1fr) minmax(0, 1.2fr);
  gap: clamp(1.75rem, 4vw, 3.5rem);
}

.footer-col { min-width: 0; }

.footer-col--brand {
  display: grid;
  align-content: start;
  gap: 0.25rem;
}

.footer-brand {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  color: var(--c-sand);
  text-decoration: none;
}

.footer-brand__mark {
  inline-size: 32px;
  block-size: 32px;
  display: grid;
  place-items: center;
  font-family: var(--f-display);
  font-size: 0.95rem;
  font-weight: 900;
  color: var(--c-sand);
  background: var(--c-danxia);
  border-radius: 54% 46% 42% 58% / 48% 56% 44% 52%;
}

.footer-brand__name {
  font-family: var(--f-display);
  font-size: 1.25rem;
  font-weight: 700;
  letter-spacing: 0.06em;
}

.footer-note {
  margin-top: 1rem;
  max-width: 34ch;
  font-size: 0.875rem;
  line-height: 1.9;
  color: var(--c-sand-54);
}

.footer-note--mono {
  margin-top: 0.5rem;
  max-width: none;
  font-family: var(--f-mono);
  font-size: 0.75rem;
  letter-spacing: 0.12em;
  color: var(--c-sandgold);
}

.footer-col__title {
  margin-bottom: 1rem;
  font-family: var(--f-mono);
  font-size: 0.6875rem;
  font-weight: 500;
  letter-spacing: 0.24em;
  text-transform: uppercase;
  color: var(--c-sandgold);
}

.footer-list {
  display: grid;
  gap: 0.55rem;
}

.footer-list a {
  font-size: 0.9375rem;
  color: var(--c-sand-72);
  text-decoration: none;
  transition: color var(--dur-fast) var(--ease-soft),
              padding-inline-start var(--dur-fast) var(--ease-soft);
}
.footer-list a:hover {
  color: var(--c-sandgold);
  padding-inline-start: 0.3rem;
}

.footer-contact {
  display: grid;
  gap: 0.85rem;
}

.footer-contact__row {
  display: grid;
  gap: 0.15rem;
}

.footer-contact__label {
  font-family: var(--f-mono);
  font-size: 0.625rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--c-sand-54);
}

.footer-contact__value {
  font-size: 0.9375rem;
  color: var(--c-sand);
  word-break: break-word;
}

.site-footer__base {
  position: relative;
  z-index: 1;
  border-top: 1px solid var(--c-sand-08);
  background: rgba(14, 47, 51, 0.42);
}

.site-footer__base-inner {
  width: min(var(--w-shell), calc(100% - var(--gutter) * 2));
  margin-inline: auto;
  padding-block: 1.15rem;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 0.5rem 1.75rem;
  font-family: var(--f-mono);
  font-size: 0.75rem;
  letter-spacing: 0.08em;
  color: var(--c-sand-54);
}

/* ---------- 7. 按钮与标签 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.85rem 1.6rem;
  font-family: var(--f-body);
  font-size: 0.9375rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-decoration: none;
  border: 1px solid transparent;
  border-radius: var(--radius-pill);
  cursor: pointer;
  transition: transform var(--dur-fast) var(--ease-soft),
              background-color var(--dur-fast) var(--ease-soft),
              color var(--dur-fast) var(--ease-soft),
              border-color var(--dur-fast) var(--ease-soft);
}
.btn:hover { transform: translateY(-2px); }
.btn:active { transform: translateY(0); }

.btn--primary {
  background: var(--c-danxia);
  border-color: var(--c-danxia);
  color: var(--c-sand);
}
.btn--primary:hover { background: #8E3124; border-color: #8E3124; }

.btn--gold {
  background: var(--c-sandgold);
  border-color: var(--c-sandgold);
  color: var(--c-night);
}
.btn--gold:hover { background: #C8923A; border-color: #C8923A; }

.btn--ghost {
  background: transparent;
  border-color: var(--c-teal-28);
  color: var(--c-teal);
}
.btn--ghost:hover {
  background: var(--c-teal-08);
  border-color: var(--c-teal);
}

.btn--quiet {
  background: transparent;
  border-color: var(--c-sand-16);
  color: var(--c-sand);
}
.btn--quiet:hover {
  border-color: var(--c-sandgold);
  color: var(--c-sandgold);
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 0.55rem;
  font-family: var(--f-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.26em;
  text-transform: uppercase;
  color: var(--c-rock);
}
.eyebrow::before {
  content: "";
  inline-size: 26px;
  block-size: 1px;
  background: var(--c-terracotta);
}

.tag {
  display: inline-flex;
  align-items: center;
  padding: 0.2rem 0.7rem;
  font-family: var(--f-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.12em;
  border-radius: var(--radius-pill);
  background: rgba(31, 166, 160, 0.14);
  border: 1px solid rgba(31, 166, 160, 0.32);
  color: #14706C;
}
.tag--gold {
  background: rgba(217, 164, 65, 0.18);
  border-color: rgba(217, 164, 65, 0.44);
  color: #8A6412;
}
.tag--red {
  background: rgba(163, 58, 43, 0.14);
  border-color: rgba(163, 58, 43, 0.32);
  color: var(--c-danxia);
}
.tag--dusk {
  background: rgba(71, 58, 102, 0.14);
  border-color: rgba(71, 58, 102, 0.32);
  color: var(--c-dusk);
}

/* ---------- 8. 面包屑 ---------- */
.breadcrumb {
  font-family: var(--f-mono);
  font-size: 0.75rem;
  letter-spacing: 0.1em;
  color: var(--c-rock);
}

.breadcrumb__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.45rem;
}

.breadcrumb__list li + li::before {
  content: "›";
  margin-inline-end: 0.45rem;
  color: rgba(107, 106, 102, 0.45);
}

.breadcrumb a {
  color: var(--c-rock);
  text-decoration: none;
  transition: color var(--dur-fast) var(--ease-soft);
}
.breadcrumb a:hover { color: var(--c-danxia); }

.breadcrumb [aria-current="page"] {
  color: var(--c-teal);
  font-weight: 500;
}

/* ---------- 9. 媒体容器（页面阶段放图片/SVG） ---------- */
.media {
  position: relative;
  overflow: hidden;
  border-radius: var(--radius-l);
  aspect-ratio: 4 / 3;
  background:
    linear-gradient(150deg,
      rgba(217, 164, 65, 0.24) 0%,
      rgba(31, 166, 160, 0.18) 52%,
      rgba(71, 58, 102, 0.26) 100%);
  box-shadow: var(--shadow-soft);
}

.media > img,
.media > svg,
.media > video,
.media > picture > img {
  inline-size: 100%;
  block-size: 100%;
  object-fit: cover;
}

.media--wide { aspect-ratio: 16 / 9; }
.media--tall { aspect-ratio: 3 / 4; }
.media--square { aspect-ratio: 1 / 1; }

.media--soft {
  border-radius: 46% 54% 40% 60% / 52% 44% 56% 48%;
}

.media--tilt { transform: rotate(-1.2deg); }

.media__caption {
  margin-top: 0.75rem;
  font-family: var(--f-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.1em;
  color: var(--c-rock);
}

/* ---------- 10. 文本工具 ---------- */
.lead {
  font-size: clamp(1.0625rem, 1.6vw, 1.25rem);
  line-height: 1.85;
  color: var(--c-teal-72);
}

.mono {
  font-family: var(--f-mono);
  letter-spacing: 0.06em;
}

.muted { color: var(--c-rock); }

.link-underline {
  color: var(--c-danxia);
  text-decoration: none;
  border-bottom: 1px solid rgba(163, 58, 43, 0.35);
  transition: color var(--dur-fast) var(--ease-soft),
              border-color var(--dur-fast) var(--ease-soft);
}
.link-underline:hover {
  color: var(--c-terracotta);
  border-bottom-color: var(--c-terracotta);
}

/* ---------- 11. 显现与筛选协议 ---------- */
[data-reveal] {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity 640ms var(--ease-soft),
              transform 640ms var(--ease-soft);
}
[data-reveal="in"] {
  opacity: 1;
  transform: none;
}

[data-filter-item][data-hidden] { display: none !important; }

[data-filter] {
  cursor: pointer;
  transition: background-color var(--dur-fast) var(--ease-soft),
              color var(--dur-fast) var(--ease-soft),
              border-color var(--dur-fast) var(--ease-soft);
}
[data-filter][aria-pressed="true"] {
  background: var(--c-paleturq);
  border-color: var(--c-turquoise);
  color: var(--c-teal);
}

/* ---------- 12. 焦点可见 ---------- */
:focus-visible {
  outline: 2px solid var(--c-turquoise);
  outline-offset: 3px;
  border-radius: 3px;
}

.section--dusk :focus-visible,
.section--teal :focus-visible,
.site-footer :focus-visible,
.site-header :focus-visible {
  outline-color: var(--c-sandgold);
}

/* ---------- 13. 响应式 ---------- */
@media (max-width: 1080px) {
  .grid--4 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .site-footer__inner {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 900px) {
  .nav-toggle { display: inline-flex; }

  .site-nav {
    position: absolute;
    left: 0;
    right: 0;
    top: 100%;
    margin-inline-start: 0;
    display: none;
    max-height: calc(100vh - 70px);
    overflow-y: auto;
    background: var(--c-teal);
    border-top: 1px solid var(--c-sand-08);
    border-bottom: 2px solid var(--c-sandgold);
    box-shadow: 0 34px 54px -32px rgba(0, 0, 0, 0.85);
  }
  .site-nav[data-open] { display: block; }

  .site-nav__list {
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: 0.75rem var(--gutter) 1.25rem;
  }

  .site-nav__list > li + li { border-top: 1px solid var(--c-sand-08); }

  .site-nav__link {
    padding: 0.95rem 0.25rem;
    font-size: 1rem;
    letter-spacing: 0.1em;
  }
  .site-nav__link::after {
    left: 0.25rem;
    right: auto;
    width: 22px;
    bottom: 0.55rem;
  }

  .header-actions { margin-inline-start: auto; }

  .header-cta--ghost { display: none; }

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

@media (min-width: 901px) {
  .header-actions { margin-inline-start: 0.75rem; }
}

@media (max-width: 680px) {
  body { font-size: 1rem; }

  .grid--2,
  .grid--3,
  .grid--4 { grid-template-columns: minmax(0, 1fr); }

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

  .site-footer__base-inner {
    flex-direction: column;
    align-items: flex-start;
  }

  .media--tilt { transform: none; }
}

@media (max-width: 520px) {
  .brand__tag { display: none; }

  .header-cta--solid {
    padding: 0.4rem 0.7rem;
    font-size: 0.75rem;
    letter-spacing: 0.04em;
  }
}

@media (max-width: 420px) {
  .nav-toggle__label {
    position: absolute;
    inline-size: 1px;
    block-size: 1px;
    overflow: hidden;
    clip-path: inset(50%);
    white-space: nowrap;
  }
  .nav-toggle { padding: 0.5rem 0.6rem; }
}

/* ---------- 14. 动效降级 ---------- */
@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;
    scroll-behavior: auto !important;
  }

  [data-reveal] {
    opacity: 1;
    transform: none;
  }

  .btn:hover { transform: none; }
  .brand:hover .brand__mark { border-radius: 58% 42% 46% 54% / 52% 48% 52% 48%; }
}