/* ============================================================
   博乐主站 · 共享样式 /assets/site.css
   回响语法：深墨蓝结构 + 回响橙节奏 + 声波弧线分割
   ============================================================ */

/* ---------- 1. reset ---------- */
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; text-size-adjust: 100%; }
body, h1, h2, h3, h4, h5, p, ul, ol, figure, blockquote, dl, dd { margin: 0; }
ul, ol { padding: 0; list-style: none; }
img, svg, video { display: block; max-width: 100%; }
img { height: auto; }
button { font: inherit; color: inherit; background: none; border: 0; cursor: pointer; }
a { color: inherit; }
table { border-collapse: collapse; width: 100%; }
:where(html) { scroll-behavior: smooth; }

/* ---------- 2. 变量 ---------- */
:root {
  /* 色彩 */
  --ink: #0B1B33;
  --ink-2: #14305A;
  --echo: #FF6B2C;
  --echo-soft: #FF8347;
  --cyan: #22D3EE;
  --sand: #E8B24A;
  --tide: #17A67A;
  --paper: #F7F5F1;
  --paper-dim: #EDEFF2;
  --mist: #C9D2DC;
  --carbon: #0A0E14;
  --deep-teal: #0E4C57;
  --slate: #46586B;

  --line-dark: rgba(201, 210, 220, .18);
  --line-light: rgba(11, 27, 51, .14);

  /* 字体 */
  --font-display: "HarmonyOS Sans SC", "Source Han Sans SC", "Noto Sans SC", Inter, system-ui, -apple-system, "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-body: "Noto Sans SC", "Source Han Sans SC", system-ui, -apple-system, "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-mono: "JetBrains Mono", "IBM Plex Mono", ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;

  /* 六级字号 */
  --fs-12: .75rem;
  --fs-14: .875rem;
  --fs-18: 1.125rem;
  --fs-28: 1.75rem;
  --fs-44: 2.75rem;
  --fs-76: clamp(3.1rem, 7.2vw, 4.75rem);
  --track-label: .14em;
  --lh-body: 1.75;

  /* 空间与形状 */
  --gutter: clamp(1.125rem, 4vw, 3rem);
  --header-h: 78px;
  --radius-s: 10px;
  --radius-m: 18px;
  --radius-l: 30px;
  --ease: cubic-bezier(.22, .61, .36, 1);
}

/* ---------- 3. 基础排版 ---------- */
body {
  font-family: var(--font-body);
  font-size: clamp(1rem, .95rem + .2vw, 1.125rem);
  line-height: var(--lh-body);
  color: var(--carbon);
  background: var(--paper);
  overflow-x: hidden;
}
h1, h2, h3, h4 {
  font-family: var(--font-display);
  font-weight: 800;
  line-height: 1.18;
  letter-spacing: -.02em;
}
p { text-wrap: pretty; }
strong { font-weight: 700; }
.display-xl { font-family: var(--font-display); font-weight: 900; font-size: var(--fs-76); line-height: 1.02; letter-spacing: -.03em; }
.display-l { font-family: var(--font-display); font-weight: 900; font-size: clamp(1.9rem, 4.4vw, 3rem); line-height: 1.08; letter-spacing: -.03em; }
.display-m { font-family: var(--font-display); font-weight: 800; font-size: clamp(1.3rem, 2.4vw, 1.75rem); line-height: 1.24; }
.eyebrow {
  display: inline-flex; align-items: center; gap: .6rem;
  font-family: var(--font-mono); font-size: var(--fs-12);
  letter-spacing: var(--track-label); text-transform: uppercase;
  color: var(--slate);
}
.eyebrow::before { content: ""; width: 26px; height: 2px; border-radius: 2px; background: var(--echo); }
.eyebrow--on-dark { color: var(--mist); }
.meta {
  font-family: var(--font-mono); font-size: var(--fs-12);
  letter-spacing: .1em; text-transform: uppercase; color: var(--slate);
}
.meta--time { color: #8A6316; }
.sr-only {
  position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px;
  overflow: hidden; clip: rect(0 0 0 0); clip-path: inset(50%); white-space: nowrap; border: 0;
}
.skip-link {
  position: absolute; left: var(--gutter); top: -4.5rem; z-index: 200;
  background: var(--echo); color: var(--ink); font-weight: 700;
  padding: .7rem 1.1rem; border-radius: 0 0 14px 14px; text-decoration: none;
  transition: top .2s var(--ease);
}
.skip-link:focus { top: 0; }
#main-content { scroll-margin-top: calc(var(--header-h) + 1rem); }

/* ---------- 4. 焦点 ---------- */
:where(a, button, [tabindex]):focus-visible {
  outline: 2px solid var(--echo); outline-offset: 3px; border-radius: 6px;
}
.site-header :focus-visible,
.site-footer :focus-visible,
.section--ink :focus-visible,
.section--teal :focus-visible { outline-color: var(--cyan); }

/* ---------- 5. 容器与栅格 ---------- */
.container { width: min(1200px, calc(100% - var(--gutter) * 2)); margin-inline: auto; }
.container--wide { width: min(1400px, calc(100% - var(--gutter) * 2)); margin-inline: auto; }
.section { padding-block: clamp(2.75rem, 7vw, 5.5rem); }
.section--paper { background: var(--paper); }
.section--dim { background: var(--paper-dim); }
.section--ink { background: var(--ink); color: var(--paper); }
.section--teal { background: var(--deep-teal); color: var(--paper); }
.section--echo { background: linear-gradient(140deg, var(--echo) 0%, #FF8A4C 100%); color: var(--ink); }
.top-space { padding-top: calc(var(--header-h) + clamp(2rem, 6vw, 4rem)); }
.grid { display: grid; gap: clamp(1.25rem, 3vw, 2.5rem); }
.grid--2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid--3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid--5-7 { grid-template-columns: 5fr 7fr; }
.grid--7-5 { grid-template-columns: 7fr 5fr; }
.grid--8-4 { grid-template-columns: 8fr 4fr; }
@media (max-width: 940px) {
  .grid--2, .grid--3, .grid--5-7, .grid--7-5, .grid--8-4 { grid-template-columns: minmax(0, 1fr); }
}

/* ---------- 6. 首屏 / 页头 ---------- */
.page-header {
  padding-top: calc(var(--header-h) + clamp(2.5rem, 7vw, 5rem));
  padding-bottom: clamp(1.5rem, 4vw, 2.75rem);
}
.page-title {
  font-family: var(--font-display); font-weight: 900;
  font-size: clamp(2.1rem, 5.4vw, 3.6rem); line-height: 1.05; letter-spacing: -.03em;
}
.prose { max-width: 36em; }
.prose--narrow { max-width: 30em; }
.prose p + p, .prose p + ul, .prose ul + p { margin-top: 1em; }
.prose a { color: var(--ink); text-decoration: underline; text-decoration-color: var(--echo); text-underline-offset: 3px; }
.prose ul { display: grid; gap: .55rem; }
.prose ul li { padding-left: 1.1rem; position: relative; }
.prose ul li::before { content: ""; position: absolute; left: 0; top: .72em; width: 8px; height: 8px; border-radius: 50%; border: 2px solid var(--echo); }

/* ---------- 7. 声波弧线分割 ---------- */
.arc-divider {
  position: relative; height: clamp(44px, 6vw, 92px);
  margin-block: clamp(1.5rem, 4vw, 3rem); overflow: hidden;
}
.arc-divider::before {
  content: ""; position: absolute; left: -12%; right: -12%; top: 55%;
  aspect-ratio: 2.6 / 1; border-top: 1px solid var(--line-light);
  border-radius: 50% 50% 0 0 / 100% 100% 0 0;
}
.arc-divider::after {
  content: ""; position: absolute; left: 8%; right: -20%; top: 30%;
  aspect-ratio: 3.4 / 1; border-top: 1px solid rgba(255, 107, 44, .35);
  border-radius: 50% 50% 0 0 / 100% 100% 0 0;
}
.arc-divider--flip::before { border-top: 0; border-bottom: 1px solid var(--line-light); border-radius: 0 0 50% 50% / 0 0 100% 100%; top: auto; bottom: 55%; }
.arc-divider--flip::after { left: -20%; right: 8%; top: auto; bottom: 30%; border-top: 0; border-bottom: 1px solid rgba(34, 211, 238, .35); border-radius: 0 0 50% 50% / 0 0 100% 100%; }

/* ---------- 8. 按钮、标签、状态 ---------- */
.btn {
  position: relative; overflow: hidden;
  display: inline-flex; align-items: center; gap: .55rem;
  font-family: var(--font-display); font-weight: 700; font-size: var(--fs-14);
  letter-spacing: .04em; text-decoration: none;
  padding: .85rem 1.4rem; border-radius: 999px;
  border: 1px solid transparent; cursor: pointer;
  transition: transform .24s var(--ease), background-color .24s var(--ease), color .24s var(--ease), border-color .24s var(--ease);
}
.btn:hover { transform: translateY(-2px); }
.btn--primary { background: var(--echo); color: var(--ink); }
.btn--primary:hover { background: var(--echo-soft); }
.btn--ghost { background: transparent; border-color: var(--mist); color: var(--ink); }
.btn--ghost:hover { border-color: var(--ink); }
.btn--on-dark { background: transparent; border-color: rgba(247, 245, 241, .4); color: var(--paper); }
.btn--on-dark:hover { border-color: var(--cyan); color: var(--cyan); }
.tag {
  display: inline-flex; align-items: center; gap: .4rem;
  font-family: var(--font-mono); font-size: var(--fs-12);
  letter-spacing: .12em; text-transform: uppercase;
  padding: .28rem .6rem; border-radius: 6px;
}
.tag--sand { background: var(--sand); color: var(--ink); }
.tag--cyan { background: var(--cyan); color: var(--ink); }
.tag--echo { background: var(--echo); color: var(--ink); }
.tag--tide { background: var(--tide); color: var(--paper); }
.tag--outline { border: 1px solid var(--mist); color: var(--slate); }
.status {
  display: inline-flex; align-items: center; gap: .45rem;
  font-family: var(--font-mono); font-size: var(--fs-12); letter-spacing: .1em;
  padding: .3rem .65rem; border-radius: 999px;
  background: rgba(232, 178, 74, .2); border: 1px solid rgba(232, 178, 74, .55); color: #6E4E11;
}
.status-dot { width: 7px; height: 7px; border-radius: 50%; background: var(--sand); flex: none; }
.status--live { background: rgba(23, 166, 122, .16); border-color: rgba(23, 166, 122, .5); color: #0C6647; }
.status--live .status-dot { background: var(--tide); }

/* ---------- 9. 卡片 ---------- */
.card {
  position: relative; overflow: hidden;
  background: #fff; border: 1px solid rgba(201, 210, 220, .7);
  border-radius: var(--radius-m);
  padding: clamp(1.15rem, 2.4vw, 1.75rem);
  transition: transform .28s var(--ease), border-color .28s var(--ease), box-shadow .28s var(--ease);
}
.card:hover { transform: translateY(-3px); box-shadow: 0 16px 34px -26px rgba(11, 27, 51, .5); }
.card--echo { border-top: 3px solid var(--echo); }
.card--cyan { border-top: 3px solid var(--cyan); }
.card--sand { border-top: 3px solid var(--sand); }
.card--tide { border-top: 3px solid var(--tide); }
.card--ink { background: var(--ink); color: var(--paper); border-color: transparent; }
.card--teal { background: var(--deep-teal); color: var(--paper); border-color: transparent; }

/* ---------- 10. 横向主题带 ---------- */
.band { overflow-x: auto; scroll-snap-type: x mandatory; -webkit-overflow-scrolling: touch; scrollbar-width: thin; }
.band-track { display: flex; gap: clamp(.75rem, 2vw, 1.25rem); padding-inline: var(--gutter); padding-block: .35rem; min-width: min-content; }
.band-item {
  scroll-snap-align: start; flex: none;
  min-width: min(300px, 78vw); max-width: 360px;
  border-radius: var(--radius-m); padding: 1.1rem 1.25rem;
  border: 1px solid var(--line-light); background: #fff;
}

/* ---------- 11. 面包屑 ---------- */
.breadcrumb { font-family: var(--font-mono); font-size: var(--fs-12); letter-spacing: .08em; color: var(--slate); }
.breadcrumb ol { display: flex; flex-wrap: wrap; gap: .5rem; }
.breadcrumb li { display: inline-flex; align-items: center; gap: .5rem; }
.breadcrumb li + li::before { content: "/"; color: var(--mist); }
.breadcrumb a { text-decoration: none; border-bottom: 1px solid transparent; transition: color .2s var(--ease), border-color .2s var(--ease); }
.breadcrumb a:hover { color: var(--echo); border-bottom-color: currentColor; }

/* ---------- 12. 图片容器（供页面阶段放置占位） ---------- */
.media {
  position: relative; display: block; overflow: hidden;
  border-radius: var(--radius-m);
  aspect-ratio: var(--ratio, 16 / 9);
  background: linear-gradient(135deg, var(--ink-2) 0%, var(--deep-teal) 100%);
  isolation: isolate;
}
.media::after {
  content: ""; position: absolute; inset: 0; pointer-events: none;
  background: radial-gradient(120% 90% at 12% 110%, rgba(34, 211, 238, .34), transparent 62%),
              radial-gradient(90% 70% at 96% -10%, rgba(255, 107, 44, .28), transparent 66%);
}
.media img { width: 100%; height: 100%; object-fit: cover; }
.media--wide { --ratio: 21 / 9; }
.media--square { --ratio: 1 / 1; }
.media--portrait { --ratio: 3 / 4; }
.media--arc { border-radius: 50% 50% var(--radius-m) var(--radius-m) / 22% 22% var(--radius-m) var(--radius-m); }
.media-frame { border-radius: var(--radius-m); overflow: hidden; border: 1px solid var(--line-light); }
.figure-caption { font-family: var(--font-mono); font-size: var(--fs-12); letter-spacing: .08em; color: var(--slate); margin-top: .6rem; }

/* ---------- 13. 头部 ---------- */
.site-header {
  position: fixed; inset: 0 0 auto 0; z-index: 80;
  padding-block: clamp(.55rem, 1.3vw, .95rem);
  color: var(--paper);
  background: linear-gradient(180deg, rgba(11, 27, 51, .94) 0%, rgba(11, 27, 51, .58) 62%, rgba(11, 27, 51, 0) 100%);
  transition: background-color .34s var(--ease), padding .34s var(--ease), box-shadow .34s var(--ease);
}
.site-header[data-scrolled],
.site-header[data-open] {
  background: var(--ink);
  background-image: none;
  box-shadow: 0 1px 0 rgba(201, 210, 220, .2);
}
.site-header[data-scrolled] { padding-block: .42rem; }
.header-inner {
  width: min(1400px, calc(100% - var(--gutter) * 2));
  margin-inline: auto;
  display: flex; align-items: center; gap: clamp(.75rem, 1.8vw, 1.6rem);
  min-height: calc(var(--header-h) - 1.4rem);
}
.brand { display: inline-flex; align-items: center; gap: .6rem; text-decoration: none; color: inherit; flex: none; }
.brand-mark {
  position: relative; width: 2rem; height: 2rem; flex: none;
  border-radius: 50%; border: 2px solid var(--echo);
}
.brand-mark::before {
  content: ""; position: absolute; inset: 5px; border-radius: 50%;
  border: 2px solid var(--cyan);
  border-right-color: transparent; border-bottom-color: transparent;
  transform: rotate(-45deg);
}
.brand-text { display: flex; flex-direction: column; line-height: 1; }
.brand-name { font-family: var(--font-display); font-weight: 900; font-size: 1.3rem; letter-spacing: .1em; }
.brand-sub { font-family: var(--font-mono); font-size: 9px; letter-spacing: .24em; color: var(--sand); margin-top: .28rem; }

.site-nav { margin-left: auto; }
.nav-list { display: flex; align-items: center; gap: clamp(.35rem, 1.4vw, 1.2rem); }
.nav-link {
  position: relative; display: inline-flex; align-items: center; gap: .3rem;
  padding: .45rem .2rem; text-decoration: none;
  font-size: var(--fs-14); font-weight: 500; letter-spacing: .05em;
  color: rgba(247, 245, 241, .82);
  transition: color .22s var(--ease);
}
.nav-link::after {
  content: ""; position: absolute; left: 50%; right: 50%; bottom: .1rem; height: 2px;
  background: var(--cyan); border-radius: 2px; transition: left .26s var(--ease), right .26s var(--ease);
}
.nav-link:hover { color: var(--paper); }
.nav-link:hover::after { left: 0; right: 0; }
.nav-link[aria-current="page"] { color: var(--cyan); font-weight: 700; }
.nav-link[aria-current="page"]::after { left: 0; right: 0; background: var(--cyan); }
.nav-link.is-entry {
  background: var(--echo); color: var(--ink); font-weight: 700;
  padding: .38rem .7rem; border-radius: 999px 8px 8px 999px;
}
.nav-link.is-entry:hover { background: var(--echo-soft); color: var(--ink); }
.nav-link.is-entry::after { display: none; }
.nav-link.is-entry[aria-current="page"] { color: var(--ink); box-shadow: inset 0 0 0 2px var(--paper); }
.nav-link-arrow { font-size: .95em; line-height: 1; }

.header-actions { margin-left: auto; display: flex; align-items: center; gap: .6rem; flex: none; }
.quick-chip {
  position: relative; overflow: hidden;
  display: inline-flex; align-items: center;
  font-family: var(--font-display); font-weight: 700; font-size: var(--fs-12);
  letter-spacing: .08em; text-decoration: none;
  padding: .5rem .85rem; border-radius: 999px;
  border: 1px solid rgba(34, 211, 238, .6); color: var(--cyan);
  transition: background-color .24s var(--ease), color .24s var(--ease);
}
.quick-chip:hover { background: var(--cyan); color: var(--ink); }
.nav-toggle {
  display: none; align-items: center; justify-content: center; flex-direction: column; gap: 5px;
  width: 44px; height: 44px; border-radius: 12px;
  border: 1px solid rgba(201, 210, 220, .45);
}
.toggle-bar { display: block; width: 20px; height: 2px; background: var(--paper); border-radius: 2px; transition: transform .28s var(--ease), opacity .2s var(--ease); }
.nav-toggle[aria-expanded="true"] .toggle-bar:nth-child(2) { transform: translateY(3.5px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] .toggle-bar:nth-child(3) { transform: translateY(-3.5px) rotate(-45deg); }
.scroll-progress {
  position: absolute; left: 0; bottom: 0; height: 2px; width: 100%;
  transform: scaleX(0); transform-origin: 0 50%;
  background: linear-gradient(90deg, var(--echo) 0%, var(--sand) 55%, var(--cyan) 100%);
}

/* ---------- 14. 页脚 ---------- */
.site-footer {
  position: relative; overflow: hidden;
  background: var(--ink); color: var(--paper);
  padding-top: clamp(2.75rem, 6vw, 5rem);
}
.site-footer::before {
  content: ""; position: absolute; right: -14%; bottom: -34%; width: min(720px, 82vw); aspect-ratio: 1;
  pointer-events: none;
  background: radial-gradient(circle at center,
    transparent 0 33%, rgba(34, 211, 238, .12) 33% 33.6%, transparent 33.6% 51%,
    rgba(255, 107, 44, .12) 51% 51.7%, transparent 51.7% 69%,
    rgba(232, 178, 74, .1) 69% 69.5%, transparent 69.5%);
}
.footer-inner {
  position: relative; z-index: 1;
  width: min(1240px, calc(100% - var(--gutter) * 2));
  margin-inline: auto;
  display: grid; grid-template-columns: minmax(200px, 1fr) minmax(0, 3fr);
  gap: clamp(2rem, 5vw, 4rem);
}
.footer-brand { display: grid; gap: 1rem; align-content: start; }
.brand--footer .brand-name { font-size: 1.5rem; }
.footer-tagline {
  font-family: var(--font-display); font-weight: 800; font-size: var(--fs-18);
  letter-spacing: .04em; color: var(--sand); line-height: 1.5;
  border-left: 2px solid var(--echo); padding-left: .85rem;
}
.footer-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(165px, 1fr)); gap: clamp(1.5rem, 3vw, 2.25rem); }
.footer-col { display: grid; gap: .9rem; align-content: start; }
.footer-heading {
  font-family: var(--font-mono); font-size: var(--fs-12); font-weight: 500;
  letter-spacing: var(--track-label); text-transform: uppercase; color: var(--cyan);
}
.footer-list { display: grid; gap: .6rem; }
.footer-link {
  display: inline-block; text-decoration: none; font-size: var(--fs-14);
  color: rgba(247, 245, 241, .78); border-bottom: 1px solid transparent;
  transition: color .22s var(--ease), border-color .22s var(--ease), transform .22s var(--ease);
}
.footer-link:hover { color: var(--echo); border-bottom-color: currentColor; transform: translateX(3px); }
.contact-list { display: grid; gap: .85rem; }
.contact-item { display: grid; gap: .2rem; }
.contact-label { font-family: var(--font-mono); font-size: var(--fs-12); letter-spacing: .1em; color: var(--mist); }
.contact-value { font-size: var(--fs-14); color: var(--paper); line-height: 1.65; }
.footer-col--contact { grid-column: span 1; }
.footer-arc {
  position: relative; z-index: 1;
  margin-top: clamp(2.25rem, 5vw, 3.75rem);
  height: clamp(34px, 5vw, 64px);
  border-top: 1px solid rgba(201, 210, 220, .26);
  border-top-left-radius: 50% 100%;
  border-top-right-radius: 50% 100%;
  background: linear-gradient(180deg, rgba(34, 211, 238, .07), transparent 78%);
}
.footer-base {
  position: relative; z-index: 1;
  width: min(1240px, calc(100% - var(--gutter) * 2));
  margin-inline: auto;
  display: flex; flex-wrap: wrap; gap: .5rem 1.5rem;
  justify-content: space-between; align-items: center;
  padding-block: 1.1rem 1.5rem;
}
.footer-copy, .footer-meta { font-family: var(--font-mono); font-size: var(--fs-12); letter-spacing: .08em; color: rgba(201, 210, 220, .85); }

/* ---------- 15. 动效与注入组件 ---------- */
[data-reveal] {
  opacity: 0; transform: translate3d(0, 18px, 0);
  transition: opacity .42s var(--ease), transform .42s var(--ease);
}
[data-reveal].is-visible { opacity: 1; transform: none; }
.ripple {
  position: absolute; border-radius: 50%; pointer-events: none;
  background: radial-gradient(circle, rgba(255, 107, 44, .5) 0%, rgba(255, 107, 44, 0) 72%);
  animation: ripple-out .62s var(--ease) forwards;
}
@keyframes ripple-out {
  from { transform: scale(.18); opacity: .95; }
  to { transform: scale(1); opacity: 0; }
}
.back-top {
  position: fixed; right: clamp(1rem, 3vw, 2rem); bottom: clamp(1rem, 3vw, 2rem); z-index: 70;
  width: 46px; height: 46px; border-radius: 50%;
  display: inline-flex; align-items: center; justify-content: center;
  background: var(--ink); color: var(--paper);
  border: 1px solid rgba(201, 210, 220, .45);
  font-size: var(--fs-18); line-height: 1;
  opacity: 0; visibility: hidden; transform: translateY(10px);
  transition: opacity .28s var(--ease), transform .28s var(--ease), visibility .28s var(--ease), border-color .24s var(--ease);
}
.back-top.is-on { opacity: 1; visibility: visible; transform: none; }
.back-top:hover { border-color: var(--echo); color: var(--echo); }

/* ---------- 16. 响应式 ---------- */
@media (max-width: 1180px) {
  :root { --header-h: 72px; }
  .nav-list { gap: .35rem; }
  .nav-link { font-size: 13px; }
}
@media (max-width: 1023px) {
  :root { --header-h: 66px; }
  .nav-toggle { display: inline-flex; }
  .header-actions { margin-left: auto; }
  .site-nav {
    position: fixed; top: 0; right: 0; bottom: 0; z-index: 70;
    width: min(86vw, 360px);
    padding: calc(var(--header-h) + 1.5rem) var(--gutter) 2.5rem;
    background: var(--ink-2);
    border-left: 1px solid var(--line-dark);
    box-shadow: -24px 0 60px -30px rgba(0, 0, 0, .8);
    overflow-y: auto;
    transform: translateX(105%); visibility: hidden;
    transition: transform .36s var(--ease), visibility .36s var(--ease);
  }
  .site-nav[data-open] { transform: translateX(0); visibility: visible; }
  .nav-list { flex-direction: column; align-items: stretch; gap: 0; }
  .nav-item { border-bottom: 1px solid var(--line-dark); }
  .nav-link { padding: 1rem .2rem; font-size: var(--fs-18); }
  .nav-link::after { display: none; }
  .nav-link.is-entry { margin-top: 1.25rem; border-radius: 12px; padding: .85rem 1rem; justify-content: space-between; }
  .footer-inner { grid-template-columns: minmax(0, 1fr); }
  .footer-arc { border-top-left-radius: 50% 60%; border-top-right-radius: 50% 60%; }
}
@media (max-width: 640px) {
  .quick-chip { padding: .45rem .7rem; letter-spacing: .04em; }
  .brand-sub { display: none; }
  .footer-grid { grid-template-columns: minmax(0, 1fr); }
  .footer-col--contact { border-top: 1px solid var(--line-dark); padding-top: 1.1rem; }
  .band-track { padding-inline: var(--gutter); }
}

/* ---------- 17. 降低动态偏好 ---------- */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: .001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .001ms !important;
  }
  [data-reveal] { opacity: 1; transform: none; }
  .ripple { display: none; }
  .btn:hover, .card:hover, .footer-link:hover { transform: none; }
}