/* ==========================================================================
   亿兆指南 · 共享样式 /assets/site.css
   1 重置 · 2 令牌 · 3 排版 · 4 布局 · 5 头部导航 · 6 页脚
   7 按钮 · 8 面包屑 · 9 内容组件 · 10 图片容器 · 11 工具类 · 12 响应式
   ========================================================================== */

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

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

body { margin: 0; }

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

ul, ol { list-style: none; }

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

a { color: inherit; }

button { font: inherit; color: inherit; background: none; border: 0; }

:focus-visible {
  outline: 2px solid #2CE5D2;
  outline-offset: 3px;
}

:focus:not(:focus-visible) { outline: none; }

/* ---------- 2 令牌 ---------- */
:root {
  --ink-deep: #081A2F;
  --indigo: #12294A;
  --cyan: #2CE5D2;
  --cyan-mist: #8BF2E7;
  --orange: #FF7A3D;
  --amber: #FFB37A;
  --jewel: #3B2A6B;
  --wine: #5E2545;
  --paper: #F4F6F8;
  --ink-text: #131E2C;
  --gray: #5A6B7C;
  --line: #D8DEE6;

  --on-dark: #E8F0F7;
  --on-dark-dim: #9CB2C6;
  --on-paper: #131E2C;
  --on-paper-dim: #5A6B7C;

  --hair: rgba(216, 222, 230, 0.16);
  --hair-cyan: rgba(44, 229, 210, 0.28);

  --font-display: "Noto Serif SC", "Source Han Serif SC", "Songti SC", "SimSun", serif;
  --font-sans: "Inter", "Noto Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", system-ui, -apple-system, sans-serif;
  --font-mono: "JetBrains Mono", "SFMono-Regular", "Cascadia Mono", Consolas, "Liberation Mono", monospace;

  --ease: cubic-bezier(0.22, 0.61, 0.36, 1);
}

body {
  font-family: var(--font-sans);
  font-size: 17px;
  line-height: 1.75;
  color: var(--on-dark);
  background-color: var(--ink-deep);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* ---------- 3 排版 ---------- */
.t-display {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(2.5rem, 7vw, 4.5rem);
  line-height: 1.12;
  letter-spacing: -0.02em;
}

.t-h1 {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(2rem, 4.6vw, 3.5rem);
  line-height: 1.16;
  letter-spacing: -0.02em;
}

.t-h2 {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(1.6rem, 3.2vw, 2.5rem);
  line-height: 1.2;
  letter-spacing: -0.02em;
}

.t-h3 {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(1.25rem, 2.2vw, 1.75rem);
  line-height: 1.3;
  letter-spacing: -0.015em;
}

.t-lead {
  font-size: clamp(1.05rem, 1.6vw, 1.25rem);
  line-height: 1.7;
  color: var(--on-dark-dim);
}

.t-body { font-size: 1rem; line-height: 1.75; }

.t-note { font-size: 0.85rem; line-height: 1.7; color: var(--on-dark-dim); }

.t-mono {
  font-family: var(--font-mono);
  font-weight: 600;
  letter-spacing: 0.02em;
  font-variant-numeric: tabular-nums;
}

.measure { max-width: 68ch; }
.measure--tight { max-width: 52ch; }

/* ---------- 4 布局 ---------- */
.wrap {
  width: 100%;
  max-width: 1240px;
  margin-inline: auto;
  padding-inline: clamp(1.1rem, 4vw, 2.5rem);
}

.wrap--narrow { max-width: 880px; }

.section {
  position: relative;
  padding-block: clamp(3rem, 7vw, 6rem);
}

.section--indigo { background-color: var(--indigo); }
.section--jewel { background-color: var(--jewel); }
.section--wine { background-color: var(--wine); }

.section--paper {
  background-color: var(--paper);
  color: var(--on-paper);
}

.section--paper .t-lead,
.section--paper .t-note { color: var(--on-paper-dim); }

.section--paper .t-mono { color: var(--ink-text); }

.section__index {
  display: block;
  font-family: var(--font-mono);
  font-weight: 600;
  font-size: clamp(1.1rem, 2vw, 1.4rem);
  color: rgba(216, 222, 230, 0.28);
  transition: color 0.3s var(--ease);
}

.section.is-current .section__index { color: var(--cyan); }

.section--paper .section__index { color: rgba(19, 30, 44, 0.24); }
.section--paper.is-current .section__index { color: var(--orange); }

.grid {
  display: grid;
  gap: clamp(1rem, 2.5vw, 2rem);
}

.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 头部与导航 ---------- */
.skip-link {
  position: absolute;
  top: 0;
  left: -9999px;
  z-index: 400;
  padding: 0.75rem 1.25rem;
  background-color: var(--cyan);
  color: #04201E;
  font-size: 0.9rem;
  font-weight: 600;
  text-decoration: none;
}

.skip-link:focus { left: 0; }

.site-header {
  position: sticky;
  top: 0;
  z-index: 120;
  background-color: var(--ink-deep);
  background-image: repeating-linear-gradient(90deg, rgba(44, 229, 210, 0.05) 0 1px, transparent 1px 96px);
  border-bottom: 1px solid var(--hair-cyan);
}

/* 上层信息条 */
.header-top {
  overflow: hidden;
  max-height: 96px;
  border-bottom: 1px solid rgba(44, 229, 210, 0.14);
  transition: max-height 0.28s var(--ease), opacity 0.22s var(--ease);
}

.site-header.is-stuck .header-top {
  max-height: 0;
  opacity: 0;
  border-bottom-color: transparent;
}

.header-top__inner {
  display: flex;
  align-items: center;
  gap: clamp(0.85rem, 2.5vw, 2rem);
  padding-block: 0.7rem;
}

.brand {
  display: flex;
  align-items: center;
  gap: 0.7rem;
  flex: 0 0 auto;
  text-decoration: none;
  color: var(--on-dark);
}

.brand__mark {
  display: grid;
  place-items: center;
  width: 38px;
  height: 38px;
  background-color: var(--cyan);
  color: #04201E;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 1.25rem;
  line-height: 1;
}

.brand__text { display: flex; flex-direction: column; }

.brand__name {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 1.05rem;
  line-height: 1.3;
  letter-spacing: 0.01em;
}

.brand__line {
  font-size: 0.72rem;
  line-height: 1.5;
  letter-spacing: 0.06em;
  color: var(--on-dark-dim);
}

.header-top__note {
  flex: 1 1 auto;
  text-align: center;
  font-size: 0.82rem;
  letter-spacing: 0.02em;
  color: var(--on-dark-dim);
}

.header-top__meta {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  flex: 0 0 auto;
  margin-left: auto;
}

.device-chip {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  padding: 0.32rem 0.6rem;
  border: 1px solid var(--hair-cyan);
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.04em;
  color: var(--cyan-mist);
  white-space: nowrap;
}

.device-chip__dot {
  width: 6px;
  height: 6px;
  background-color: var(--cyan);
  animation: yz-pulse 2.6s ease-in-out infinite;
}

@keyframes yz-pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.3; }
}

/* 下层栏目条 */
.header-bottom {
  background-image: linear-gradient(90deg, var(--indigo) 0%, #0B2138 58%, var(--ink-deep) 100%);
}

.header-bottom__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.nav { flex: 1 1 auto; }

.nav__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: clamp(0.2rem, 1.6vw, 1.4rem);
}

.nav__link {
  position: relative;
  display: inline-block;
  padding: 0.85rem 0.3rem;
  color: var(--on-dark-dim);
  font-size: 0.95rem;
  letter-spacing: 0.02em;
  text-decoration: none;
  transition: color 0.2s var(--ease);
}

.nav__link::after {
  content: "";
  position: absolute;
  left: 0.3rem;
  right: 0.3rem;
  bottom: 0.5rem;
  height: 1px;
  background-color: var(--cyan);
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform 0.24s var(--ease);
}

.nav__link:hover { color: var(--on-dark); }
.nav__link:hover::after { transform: scaleX(1); }

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

.nav__link[aria-current="page"]::after { transform: scaleX(1); }

.nav-toggle {
  display: none;
  align-items: center;
  gap: 0.5rem;
  flex: 0 0 auto;
  padding: 0.5rem 0.7rem;
  border: 1px solid var(--hair-cyan);
  color: var(--cyan);
  font-size: 0.8rem;
  letter-spacing: 0.1em;
  cursor: pointer;
}

.nav-toggle__label { font-size: 0.8rem; }

.nav-toggle__bars {
  position: relative;
  display: block;
  width: 18px;
  height: 1.5px;
  background-color: currentColor;
  transition: background-color 0.2s var(--ease);
}

.nav-toggle__bars::before,
.nav-toggle__bars::after {
  content: "";
  position: absolute;
  left: 0;
  width: 18px;
  height: 1.5px;
  background-color: currentColor;
  transition: transform 0.24s var(--ease);
}

.nav-toggle__bars::before { top: -6px; }
.nav-toggle__bars::after { bottom: -6px; }

.nav-toggle[aria-expanded="true"] .nav-toggle__bars { background-color: transparent; }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars::before { transform: translateY(6px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars::after { transform: translateY(-6px) rotate(-45deg); }

/* 阅读进度 */
.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  z-index: 200;
  background-color: rgba(44, 229, 210, 0.14);
  pointer-events: none;
}

.scroll-progress__bar {
  display: block;
  width: 100%;
  height: 100%;
  background-image: linear-gradient(90deg, var(--cyan), var(--orange));
  transform: scaleX(0);
  transform-origin: left center;
}

/* ---------- 6 页脚 ---------- */
.site-footer {
  padding-top: clamp(2.5rem, 5vw, 4.5rem);
  padding-bottom: 0;
  background-color: var(--ink-deep);
  background-image: repeating-linear-gradient(90deg, rgba(44, 229, 210, 0.05) 0 1px, transparent 1px 96px);
  border-top: 1px solid var(--hair-cyan);
  color: var(--on-dark);
}

.footer-grid {
  display: grid;
  grid-template-columns: minmax(220px, 1.5fr) repeat(3, minmax(150px, 1fr));
  gap: clamp(1.5rem, 4vw, 3rem);
}

.footer-brand__name {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(1.5rem, 2.4vw, 1.9rem);
  line-height: 1.25;
  letter-spacing: -0.02em;
}

.footer-brand__mark {
  display: block;
  margin-top: 0.5rem;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  font-weight: 600;
  letter-spacing: 0.2em;
  color: var(--cyan);
}

.footer-brand__text {
  margin-top: 1rem;
  max-width: 30ch;
  font-size: 0.9rem;
  line-height: 1.75;
  color: var(--on-dark-dim);
}

.footer-col__title {
  padding-bottom: 0.65rem;
  border-bottom: 1px solid var(--hair-cyan);
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.18em;
  color: var(--cyan);
}

.footer-list { margin-top: 1rem; }

.footer-list li + li { margin-top: 0.55rem; }

.footer-list a {
  display: inline-block;
  padding-bottom: 1px;
  border-bottom: 1px solid transparent;
  font-size: 0.9rem;
  color: var(--on-dark-dim);
  text-decoration: none;
  transition: color 0.2s var(--ease), border-color 0.2s var(--ease);
}

.footer-list a:hover {
  color: var(--cyan);
  border-bottom-color: var(--cyan);
}

.footer-list--facts li {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 1rem;
  font-size: 0.85rem;
}

.footer-list--facts span { color: var(--gray); }

.footer-list--facts strong {
  font-family: var(--font-mono);
  font-weight: 600;
  font-size: 0.8rem;
  color: var(--amber);
}

.footer-facts { margin-top: 1rem; }

.footer-facts dt {
  margin-top: 1rem;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  font-weight: 600;
  letter-spacing: 0.14em;
  color: var(--cyan-mist);
}

.footer-facts dt:first-of-type { margin-top: 0; }

.footer-facts dd {
  margin-top: 0.3rem;
  font-size: 0.9rem;
  line-height: 1.6;
  color: var(--on-dark);
  word-break: break-word;
}

.footer-note {
  margin-top: 1.1rem;
  padding-left: 0.75rem;
  border-left: 1px solid var(--hair-cyan);
  font-size: 0.78rem;
  line-height: 1.7;
  color: var(--gray);
}

.footer-base {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem 1.5rem;
  margin-top: clamp(2rem, 4vw, 3.5rem);
  padding-block: 1.25rem 1.6rem;
  border-top: 1px solid rgba(216, 222, 230, 0.16);
  font-size: 0.8rem;
  color: var(--gray);
}

.footer-base__links {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem 1.25rem;
}

.footer-base__links a {
  color: var(--on-dark-dim);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color 0.2s var(--ease), border-color 0.2s var(--ease);
}

.footer-base__links a:hover {
  color: var(--cyan);
  border-bottom-color: var(--cyan);
}

/* ---------- 7 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.7rem 1.15rem;
  border: 1px solid transparent;
  font-family: var(--font-sans);
  font-size: 0.9rem;
  font-weight: 600;
  letter-spacing: 0.02em;
  text-decoration: none;
  cursor: pointer;
  transition: background-color 0.2s var(--ease), color 0.2s var(--ease), border-color 0.2s var(--ease);
}

.btn--primary {
  background-color: var(--orange);
  border-color: var(--orange);
  color: #24100A;
}

.btn--primary:hover {
  background-color: var(--amber);
  border-color: var(--amber);
}

.btn--ghost {
  background-color: transparent;
  border-color: var(--hair-cyan);
  color: var(--cyan);
}

.btn--ghost:hover {
  background-color: rgba(44, 229, 210, 0.12);
  border-color: var(--cyan);
}

.btn--onpaper {
  background-color: transparent;
  border-color: rgba(19, 30, 44, 0.35);
  color: var(--ink-text);
}

.btn--onpaper:hover {
  border-color: var(--ink-text);
  background-color: rgba(19, 30, 44, 0.06);
}

.btn--sm { padding: 0.42rem 0.8rem; font-size: 0.8rem; }

.btn--block { width: 100%; }

/* ---------- 8 面包屑 ---------- */
.breadcrumb {
  padding-block: 1.1rem;
  border-bottom: 1px solid var(--hair);
}

.breadcrumb ol {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.55rem;
  font-size: 0.8rem;
  color: var(--on-dark-dim);
}

.breadcrumb li:not(:last-child)::after {
  content: "/";
  margin-left: 0.55rem;
  color: rgba(216, 222, 230, 0.35);
}

.breadcrumb a {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(44, 229, 210, 0.4);
}

.breadcrumb [aria-current="page"] { color: var(--on-dark); }

/* ---------- 9 内容组件 ---------- */
.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.2em;
  color: var(--cyan);
}

.eyebrow::before {
  content: "";
  width: 22px;
  height: 1px;
  background-color: currentColor;
}

.section--paper .eyebrow { color: var(--wine); }

.tag {
  display: inline-block;
  padding: 0.24rem 0.55rem;
  border: 1px solid rgba(255, 179, 122, 0.42);
  background-color: rgba(255, 179, 122, 0.14);
  font-family: var(--font-mono);
  font-size: 0.7rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  color: var(--amber);
}

.card {
  position: relative;
  padding: clamp(1.25rem, 2.5vw, 1.75rem);
  border: 1px solid var(--hair);
  background-color: var(--indigo);
  transition: border-color 0.24s var(--ease), background-color 0.24s var(--ease);
}

.card:hover,
.card:focus-within { border-color: var(--cyan); }

.card__meta {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.16em;
  color: var(--cyan);
}

.card__title {
  margin-top: 0.6rem;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 1.35rem;
  line-height: 1.35;
  letter-spacing: -0.015em;
}

.card__text {
  margin-top: 0.6rem;
  font-size: 0.95rem;
  line-height: 1.75;
  color: var(--on-dark-dim);
}

.card__reveal {
  max-height: 0;
  overflow: hidden;
  opacity: 0;
  transition: max-height 0.3s var(--ease), opacity 0.24s var(--ease), margin-top 0.3s var(--ease);
}

.card:hover .card__reveal,
.card:focus-within .card__reveal {
  max-height: 9rem;
  margin-top: 0.85rem;
  opacity: 1;
}

.card--paper {
  background-color: #FFFFFF;
  border-color: var(--line);
}

.card--paper .card__text { color: var(--on-paper-dim); }
.card--paper .card__title { color: var(--on-paper); }
.card--paper .card__meta { color: var(--wine); }

.card--paper:hover,
.card--paper:focus-within { border-color: var(--orange); }

.stat { display: block; }

.stat__value {
  display: block;
  font-family: var(--font-mono);
  font-weight: 600;
  font-size: clamp(1.75rem, 4vw, 2.5rem);
  line-height: 1.1;
  color: var(--orange);
}

.stat__label {
  display: block;
  margin-top: 0.5rem;
  font-size: 0.85rem;
  color: var(--on-dark-dim);
}

.section--paper .stat__label { color: var(--on-paper-dim); }

.rule {
  width: 100%;
  height: 1px;
  background-color: var(--hair);
  border: 0;
}

/* 标签页（设备切换 / 问答分组 / 专栏筛选） */
.tabs {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  padding-bottom: 1rem;
  border-bottom: 1px solid var(--hair);
}

.tab {
  padding: 0.5rem 0.9rem;
  border: 1px solid var(--hair);
  background-color: transparent;
  font-size: 0.85rem;
  letter-spacing: 0.02em;
  color: var(--on-dark-dim);
  cursor: pointer;
  transition: color 0.2s var(--ease), border-color 0.2s var(--ease), background-color 0.2s var(--ease);
}

.tab:hover { color: var(--on-dark); border-color: var(--hair-cyan); }

.tab[aria-selected="true"] {
  background-color: var(--cyan);
  border-color: var(--cyan);
  color: #04201E;
  font-weight: 600;
}

.panel { padding-top: 1.5rem; }

/* ---------- 10 图片容器 ---------- */
.media {
  position: relative;
  display: block;
  width: 100%;
  overflow: hidden;
  border: 1px solid var(--hair);
  background-image: linear-gradient(135deg, var(--indigo), var(--ink-deep));
}

.media::after {
  content: "";
  position: absolute;
  inset: 0;
  background-image: repeating-linear-gradient(45deg, rgba(44, 229, 210, 0.06) 0 1px, transparent 1px 14px);
  pointer-events: none;
}

.media img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.media--21x9 { aspect-ratio: 21 / 9; }
.media--16x9 { aspect-ratio: 16 / 9; }
.media--4x3 { aspect-ratio: 4 / 3; }
.media--1x1 { aspect-ratio: 1 / 1; }
.media--3x4 { aspect-ratio: 3 / 4; }

.media__caption {
  margin-top: 0.65rem;
  font-size: 0.8rem;
  line-height: 1.7;
  color: var(--on-dark-dim);
}

.section--paper .media__caption { color: var(--on-paper-dim); }

/* ---------- 11 工具类 ---------- */
.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  margin: -1px;
  padding: 0;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
  border: 0;
}

.text-cyan { color: var(--cyan); }
.text-orange { color: var(--orange); }
.text-dim { color: var(--on-dark-dim); }
.stack-sm > * + * { margin-top: 0.75rem; }
.stack-md > * + * { margin-top: 1.25rem; }
.stack-lg > * + * { margin-top: 2rem; }

html.js [data-reveal] {
  opacity: 0;
  transform: translateY(14px);
  transition: opacity 0.5s var(--ease), transform 0.5s var(--ease);
}

html.js [data-reveal].is-visible {
  opacity: 1;
  transform: none;
}

/* ---------- 12 响应式 ---------- */
@media (max-width: 1024px) {
  .grid--4 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .grid--3 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .footer-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .footer-brand { grid-column: 1 / -1; }
}

@media (max-width: 880px) {
  .nav-toggle { display: inline-flex; }

  .header-bottom__inner { padding-block: 0.45rem; }

  .nav {
    position: fixed;
    left: 0;
    right: 0;
    bottom: 0;
    z-index: 130;
    max-height: 74vh;
    overflow-y: auto;
    padding: 1.1rem clamp(1rem, 4vw, 1.5rem) calc(1.4rem + env(safe-area-inset-bottom, 0px));
    background-color: var(--indigo);
    background-image: repeating-linear-gradient(90deg, rgba(44, 229, 210, 0.06) 0 1px, transparent 1px 72px);
    border-top: 1px solid var(--cyan);
    visibility: hidden;
    transform: translateY(105%);
    transition: transform 0.3s var(--ease), visibility 0.3s var(--ease);
  }

  .nav[data-open] {
    visibility: visible;
    transform: translateY(0);
  }

  .nav__list {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 0.2rem 1.25rem;
  }

  .nav__link {
    width: 100%;
    padding: 0.85rem 0.2rem;
    border-bottom: 1px solid rgba(216, 222, 230, 0.14);
    font-size: 1rem;
  }

  .nav__link::after { display: none; }

  .nav__link[aria-current="page"] {
    color: var(--cyan);
    border-bottom-color: var(--cyan);
  }

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

  .breadcrumb { padding-block: 0.9rem; }
}

@media (max-width: 680px) {
  .header-top__note { display: none; }
  .device-chip { display: none; }

  .footer-grid { grid-template-columns: minmax(0, 1fr); }
  .footer-brand { grid-column: auto; }
  .footer-brand__text { max-width: 100%; }

  .footer-base {
    flex-direction: column;
    align-items: flex-start;
  }
}

@media (max-width: 420px) {
  .brand__line { font-size: 0.66rem; letter-spacing: 0.03em; }
  .brand__mark { width: 34px; height: 34px; font-size: 1.1rem; }
  .btn--sm { padding: 0.36rem 0.6rem; font-size: 0.74rem; }
  .nav__list { grid-template-columns: minmax(0, 1fr); }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }

  *,
  *::before,
  *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
  }

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

  .device-chip__dot { animation: none; }
}