/* =========================================================
   亿百CN 共享样式 / assets/site.css
   ========================================================= */

*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
body, h1, h2, h3, h4, h5, p, ul, ol, dl, dd, figure, blockquote { margin: 0; }
ul, ol { padding: 0; list-style: none; }
img, svg { display: block; max-width: 100%; }
button { font: inherit; color: inherit; background: none; border: 0; cursor: pointer; }
a { color: inherit; text-decoration: none; }
details summary { list-style: none; }

:root {
  --ink: #0C1B20;
  --mist: #F5F8F8;
  --haze: #D7E1E4;
  --teal: #0F6B7A;
  --teal-deep: #0A4E59;
  --teal-soft: #4FA3AE;
  --sand: #E27A3F;
  --sand-deep: #CF6A2F;
  --flag: #C24A3F;
  --gray: #7C8B8F;
  --white: #FFFFFF;

  --ink-80: rgba(12, 27, 32, 0.8);
  --ink-60: rgba(12, 27, 32, 0.62);
  --hair: rgba(12, 27, 32, 0.14);
  --hair-soft: rgba(12, 27, 32, 0.08);

  --shell: 1180px;
  --gutter: clamp(1.15rem, 3.6vw, 3rem);

  --font-head: "Noto Sans SC", "Source Han Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-body: "Noto Serif SC", "Source Han Serif SC", "Songti SC", "SimSun", serif;
  --font-mono: "JetBrains Mono", "IBM Plex Mono", "SFMono-Regular", Consolas, monospace;

  --r-lg: 28px;
  --r-md: 18px;
  --r-sm: 12px;
  --r-pill: 999px;

  --shadow-card: 0 18px 40px -32px rgba(12, 27, 32, 0.55);
  --ease: cubic-bezier(0.2, 0.7, 0.3, 1);
}

/* ---------- 中文排版基座 ---------- */
body {
  font-family: var(--font-body);
  font-size: 17px;
  line-height: 1.85;
  letter-spacing: 0.01em;
  color: var(--ink);
  background: var(--mist);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}
@media (min-width: 900px) { body { font-size: 18px; } }

h1, h2, h3, h4, h5 {
  font-family: var(--font-head);
  font-weight: 900;
  line-height: 1.12;
  letter-spacing: -0.03em;
  text-wrap: balance;
}

.display { font-size: clamp(3.2rem, 6vw, 5.4rem); line-height: 0.98; letter-spacing: -0.05em; }
.h1, .page-title { font-size: clamp(2rem, 3vw, 2.8rem); }
.h2, .section-title { font-size: clamp(1.4rem, 2vw, 1.75rem); letter-spacing: -0.02em; }

.mono { font-family: var(--font-mono); font-size: 0.74rem; letter-spacing: 0.14em; text-transform: uppercase; }

.path-term {
  font-family: var(--font-mono);
  font-size: 0.9em;
  color: var(--teal-deep);
  text-decoration: underline;
  text-decoration-color: var(--sand);
  text-decoration-thickness: 2px;
  text-underline-offset: 0.28em;
}

.prose { max-width: 72ch; }
.prose > * + * { margin-top: 1.05em; }
.prose strong { font-weight: 700; color: var(--teal-deep); }

/* ---------- 焦点 ---------- */
:focus-visible {
  outline: 3px solid var(--teal);
  outline-offset: 3px;
  border-radius: 4px;
}
.site-footer :focus-visible { outline-color: var(--sand); }

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

.section { padding-block: clamp(2.8rem, 6vw, 5.5rem); }
.section--tint { background: var(--haze); }
.section--paper { background: var(--white); }

.section-head {
  display: flex;
  flex-wrap: wrap;
  align-items: flex-end;
  justify-content: space-between;
  gap: 1rem;
  margin-bottom: clamp(1.6rem, 3vw, 2.6rem);
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 0.55rem;
  font-family: var(--font-mono);
  font-size: 0.74rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--teal-deep);
}
.eyebrow::before { content: ""; width: 1.6rem; height: 2px; background: var(--sand); }

.grid-12 {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: clamp(1rem, 2vw, 1.6rem);
}
.col-main { grid-column: 1 / 8; min-width: 0; }
.col-side { grid-column: 9 / 13; min-width: 0; }
@media (max-width: 900px) {
  .col-main, .col-side { grid-column: 1 / -1; }
}

/* ---------- 跳过链接 ---------- */
.skip-link {
  position: fixed;
  top: 0.6rem;
  left: 0.6rem;
  z-index: 200;
  transform: translateY(-180%);
  padding: 0.62rem 1.1rem;
  border-radius: var(--r-pill);
  background: var(--ink);
  color: var(--mist);
  font-family: var(--font-head);
  font-size: 0.88rem;
  font-weight: 700;
  transition: transform 0.22s var(--ease);
}
.skip-link:focus { transform: translateY(0); }

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.55rem;
  padding: 0.72rem 1.35rem;
  border-radius: var(--r-pill);
  border: 1px solid transparent;
  font-family: var(--font-head);
  font-weight: 800;
  font-size: 0.94rem;
  letter-spacing: 0.01em;
  transition: background 0.2s var(--ease), color 0.2s var(--ease),
              border-color 0.2s var(--ease), transform 0.2s var(--ease);
}
.btn--primary { background: var(--teal); color: var(--white); }
.btn--primary:hover { background: var(--teal-deep); transform: translateY(-1px); }
.btn--action { background: var(--sand); color: var(--ink); }
.btn--action:hover { background: var(--sand-deep); transform: translateY(-1px); }
.btn--ghost { border-color: rgba(12, 27, 32, 0.28); color: var(--ink); }
.btn--ghost:hover { border-color: var(--teal); color: var(--teal-deep); background: rgba(15, 107, 122, 0.06); }
.btn--on-dark { border-color: rgba(245, 248, 248, 0.4); color: var(--mist); }
.btn--on-dark:hover { background: rgba(245, 248, 248, 0.12); border-color: var(--sand); color: var(--sand); }

/* ---------- 胶囊 / 标签 ---------- */
.pill {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  padding: 0.3rem 0.78rem;
  border-radius: var(--r-pill);
  border: 1px solid rgba(15, 107, 122, 0.28);
  background: rgba(255, 255, 255, 0.72);
  color: var(--teal-deep);
  font-family: var(--font-head);
  font-size: 0.74rem;
  font-weight: 700;
  letter-spacing: 0.02em;
  white-space: nowrap;
}
.pill--quiet { background: var(--white); border-color: var(--hair); color: var(--ink-80); font-weight: 600; }
.pill--sand { background: var(--sand); border-color: transparent; color: var(--ink); }
.pill--flag { background: var(--flag); border-color: transparent; color: var(--white); }
.pill--footer {
  background: rgba(245, 248, 248, 0.08);
  border-color: rgba(245, 248, 248, 0.2);
  color: rgba(245, 248, 248, 0.88);
}
.pill__dot {
  width: 0.42rem;
  height: 0.42rem;
  border-radius: 50%;
  background: var(--teal);
  box-shadow: 0 0 0 3px rgba(15, 107, 122, 0.16);
}

.tag {
  display: inline-flex;
  align-items: center;
  padding: 0.22rem 0.6rem;
  border-radius: var(--r-pill);
  background: var(--haze);
  color: var(--teal-deep);
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.06em;
}

/* =========================================================
   页头
   ========================================================= */
.site-header {
  position: relative;
  z-index: 60;
  background: var(--mist);
}

.header-utility { background: var(--ink); color: rgba(245, 248, 248, 0.86); }
.header-utility__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 0.5rem 0;
  font-size: 0.74rem;
  letter-spacing: 0.06em;
}
.header-utility__place { display: flex; align-items: center; gap: 0.6rem; }
.header-utility__place .mono { color: var(--teal-soft); font-size: 0.7rem; }
.header-utility__meta { color: rgba(245, 248, 248, 0.66); }

.masthead {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto minmax(0, 1fr);
  align-items: center;
  gap: 1.5rem;
  padding: clamp(1.3rem, 3vw, 2.1rem) 0 clamp(1rem, 2.4vw, 1.6rem);
}
.masthead__aside {
  display: flex;
  flex-direction: column;
  gap: 0.55rem;
  font-size: 0.72rem;
  color: var(--gray);
}
.masthead__aside--start { align-items: flex-start; text-align: left; }
.masthead__aside--end { align-items: flex-end; text-align: right; }
.masthead__mark { color: var(--teal-deep); font-size: 0.7rem; }

.masthead__brand { display: block; text-align: center; }
.masthead__brand-name {
  display: block;
  font-family: var(--font-head);
  font-weight: 900;
  font-size: clamp(2rem, 5vw, 2.9rem);
  line-height: 1;
  letter-spacing: -0.05em;
  color: var(--ink);
}
.masthead__brand-name::after {
  content: "";
  display: inline-block;
  width: 0.3em;
  height: 0.3em;
  margin-left: 0.16em;
  border-radius: 2px;
  background: var(--flag);
  vertical-align: baseline;
}
.masthead__brand-sub {
  display: block;
  margin-top: 0.55rem;
  font-family: var(--font-head);
  font-weight: 600;
  font-size: 0.72rem;
  letter-spacing: 0.42em;
  text-indent: 0.42em;
  color: var(--gray);
}

/* 目录条 */
.nav-bar {
  background: var(--white);
  border-top: 1px solid var(--hair);
  border-bottom: 1px solid var(--hair);
}
.nav-bar__inner {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto minmax(0, 1fr);
  align-items: center;
  gap: 1rem;
  padding: 0.5rem 0;
}
.nav-bar__index {
  justify-self: start;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.16em;
  color: var(--gray);
}

.primary-nav { display: block; }
.primary-nav__list {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: clamp(0.9rem, 2.4vw, 2rem);
}
.primary-nav__list a {
  position: relative;
  display: inline-block;
  padding: 0.5rem 0.1rem;
  font-family: var(--font-head);
  font-weight: 700;
  font-size: 0.92rem;
  letter-spacing: 0.01em;
  color: var(--ink-80);
  transition: color 0.2s var(--ease);
}
.primary-nav__list a::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0.14rem;
  height: 2px;
  background: var(--teal);
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform 0.28s var(--ease), background 0.2s var(--ease);
}
.primary-nav__list a:hover { color: var(--teal-deep); }
.primary-nav__list a:hover::after { transform: scaleX(1); }
.primary-nav__list a[aria-current="page"] { color: var(--teal-deep); }
.primary-nav__list a[aria-current="page"]::after { transform: scaleX(1); background: var(--sand); }

.nav-bar__entry {
  justify-self: end;
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.46rem 0.98rem;
  border-radius: var(--r-pill);
  background: var(--sand);
  color: var(--ink);
  font-family: var(--font-head);
  font-weight: 800;
  font-size: 0.8rem;
  letter-spacing: 0.02em;
  white-space: nowrap;
  transition: background 0.2s var(--ease), transform 0.2s var(--ease);
}
.nav-bar__entry::after { content: "→"; font-family: var(--font-mono); }
.nav-bar__entry:hover { background: var(--sand-deep); transform: translateY(-1px); }

/* 移动导航按钮 */
.nav-toggle {
  display: none;
  align-items: center;
  gap: 0.55rem;
  padding: 0.5rem 0.95rem;
  border-radius: var(--r-pill);
  border: 1px solid var(--hair);
  background: var(--mist);
  color: var(--ink);
  font-family: var(--font-head);
  font-weight: 700;
  font-size: 0.82rem;
}
.nav-toggle__bars {
  position: relative;
  width: 18px;
  height: 2px;
  background: currentColor;
  transition: background 0.2s var(--ease);
}
.nav-toggle__bars::before,
.nav-toggle__bars::after {
  content: "";
  position: absolute;
  left: 0;
  width: 18px;
  height: 2px;
  background: currentColor;
  transition: transform 0.22s var(--ease), top 0.22s var(--ease);
}
.nav-toggle__bars::before { top: -6px; }
.nav-toggle__bars::after { top: 6px; }
.nav-toggle[aria-expanded="true"] { background: var(--teal); border-color: var(--teal); color: var(--white); }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars { background: transparent; }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars::before { top: 0; transform: rotate(45deg); }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars::after { top: 0; transform: rotate(-45deg); }
.nav-toggle__label { line-height: 1; }

@keyframes navIn {
  from { opacity: 0; transform: translateY(-6px); }
  to { opacity: 1; transform: none; }
}

@media (max-width: 900px) {
  .masthead {
    grid-template-columns: minmax(0, 1fr);
    justify-items: center;
    gap: 0.85rem;
    padding: 1.1rem 0 1.2rem;
  }
  .masthead__aside--start { display: none; }
  .masthead__aside--end {
    flex-direction: row;
    flex-wrap: wrap;
    justify-content: center;
    align-items: center;
    text-align: center;
  }

  .nav-bar__inner {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    justify-content: space-between;
    gap: 0.6rem;
    padding: 0.6rem 0;
  }
  .nav-bar__index { display: none; }
  .nav-toggle { display: inline-flex; order: 1; }
  .nav-bar__entry { order: 2; font-size: 0.76rem; padding: 0.42rem 0.85rem; }

  .primary-nav {
    order: 3;
    flex: 1 0 100%;
    display: none;
    margin-top: 0.15rem;
    padding-top: 0.35rem;
    border-top: 1px solid var(--hair);
  }
  .primary-nav[data-open] { display: block; animation: navIn 0.24s var(--ease); }
  .primary-nav__list { flex-direction: column; align-items: stretch; gap: 0; }
  .primary-nav__list a {
    display: block;
    padding: 0.7rem 0.3rem;
    font-size: 0.95rem;
    border-bottom: 1px dashed var(--hair-soft);
  }
  .primary-nav__list a::after { display: none; }
  .primary-nav__list a[aria-current="page"] {
    padding-left: 0.7rem;
    border-left: 3px solid var(--sand);
    background: rgba(15, 107, 122, 0.08);
    border-radius: 0 6px 6px 0;
  }
}

/* =========================================================
   页脚
   ========================================================= */
.site-footer {
  position: relative;
  overflow: hidden;
  padding: clamp(2.6rem, 5vw, 4rem) 0 1.4rem;
  background: var(--ink);
  color: rgba(245, 248, 248, 0.82);
}
.site-footer::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(245, 248, 248, 0.055) 1px, transparent 1px),
    linear-gradient(90deg, rgba(245, 248, 248, 0.055) 1px, transparent 1px);
  background-size: 64px 64px;
  -webkit-mask-image: linear-gradient(to bottom, rgba(0, 0, 0, 0.9), transparent 78%);
  mask-image: linear-gradient(to bottom, rgba(0, 0, 0, 0.9), transparent 78%);
  pointer-events: none;
}

.footer-top {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: 1.5fr 0.8fr 0.9fr 1.1fr;
  gap: clamp(1.6rem, 4vw, 3rem);
}

.footer-brand__eyebrow {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--teal-soft);
}
.footer-brand__name {
  margin-top: 0.8rem;
  font-family: var(--font-head);
  font-weight: 900;
  font-size: clamp(1.35rem, 2.4vw, 1.85rem);
  letter-spacing: -0.03em;
  color: var(--mist);
}
.footer-brand__summary {
  margin-top: 0.75rem;
  max-width: 34ch;
  font-size: 0.94rem;
  line-height: 1.8;
  color: rgba(245, 248, 248, 0.66);
}
.footer-brand__status {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-top: 1.1rem;
}

.footer-col__title {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  font-weight: 600;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: rgba(245, 248, 248, 0.5);
}
.footer-col__list { display: grid; gap: 0.55rem; margin-top: 1rem; }
.footer-col__list a {
  display: inline-block;
  font-family: var(--font-head);
  font-size: 0.92rem;
  color: rgba(245, 248, 248, 0.86);
  transition: color 0.2s var(--ease), padding-left 0.2s var(--ease);
}
.footer-col__list a:hover { color: var(--sand); padding-left: 0.25rem; }

.footer-contact__list { display: grid; gap: 0.85rem; margin-top: 1rem; }
.footer-contact__item { display: grid; gap: 0.15rem; }
.footer-contact__label {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--teal-soft);
}
.footer-contact__value {
  font-size: 0.92rem;
  color: rgba(245, 248, 248, 0.86);
  overflow-wrap: anywhere;
}
.footer-contact__note {
  margin-top: 1rem;
  padding-left: 0.75rem;
  border-left: 2px solid var(--sand);
  font-size: 0.8rem;
  line-height: 1.7;
  color: rgba(245, 248, 248, 0.52);
}

.footer-base {
  position: relative;
  z-index: 1;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 0.8rem 1.6rem;
  margin-top: clamp(2rem, 4vw, 3rem);
  padding-top: 1.1rem;
  border-top: 1px solid rgba(245, 248, 248, 0.16);
  font-size: 0.78rem;
  color: rgba(245, 248, 248, 0.55);
}
.footer-base__copy { letter-spacing: 0.04em; }
.footer-base__icp { font-family: var(--font-mono); font-size: 0.72rem; letter-spacing: 0.08em; }
.footer-legal { display: flex; flex-wrap: wrap; gap: 0.9rem; }
.footer-legal a {
  color: rgba(245, 248, 248, 0.72);
  border-bottom: 1px solid rgba(245, 248, 248, 0.25);
  padding-bottom: 1px;
  transition: color 0.2s var(--ease), border-color 0.2s var(--ease);
}
.footer-legal a:hover { color: var(--sand); border-color: var(--sand); }

@media (max-width: 1000px) {
  .footer-top { grid-template-columns: 1.4fr 1fr 1fr; }
  .footer-contact { grid-column: 1 / -1; }
}
@media (max-width: 680px) {
  .footer-top { grid-template-columns: 1fr 1fr; }
  .footer-brand { grid-column: 1 / -1; }
  .footer-base { flex-direction: column; align-items: flex-start; gap: 0.6rem; }
}

/* =========================================================
   通用内容组件（页面阶段复用）
   ========================================================= */
.breadcrumb { margin-block: 1.4rem 0.2rem; }
.breadcrumb__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.35rem;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.08em;
  color: var(--gray);
}
.breadcrumb__item { display: inline-flex; align-items: center; }
.breadcrumb__item:not(:last-child)::after {
  content: "/";
  margin-left: 0.35rem;
  color: rgba(12, 27, 32, 0.22);
}
.breadcrumb__item a { color: var(--teal-deep); border-bottom: 1px dotted rgba(15, 107, 122, 0.5); }
.breadcrumb__item a:hover { border-color: var(--sand); }
.breadcrumb__item[aria-current="page"] { color: var(--ink); }

.archive-card {
  position: relative;
  padding: clamp(1.1rem, 2.2vw, 1.6rem);
  border: 1px solid var(--hair);
  border-radius: var(--r-md);
  background: var(--white);
  box-shadow: var(--shadow-card);
  transition: border-color 0.2s var(--ease), transform 0.2s var(--ease);
}
.archive-card:hover { border-color: rgba(15, 107, 122, 0.42); transform: translateY(-2px); }
.archive-card__num {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.14em;
  color: var(--flag);
}
.archive-card__title {
  margin-top: 0.5rem;
  font-family: var(--font-head);
  font-size: 1.12rem;
  font-weight: 800;
  letter-spacing: -0.02em;
}
.archive-card__text {
  margin-top: 0.5rem;
  font-size: 0.94rem;
  line-height: 1.8;
  color: var(--ink-80);
}
.archive-card__foot {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.5rem;
  margin-top: 1rem;
  padding-top: 0.8rem;
  border-top: 1px dashed var(--hair);
}

.record-list { display: grid; gap: 0.6rem; }
.record-row {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr) auto auto;
  align-items: center;
  gap: 1rem;
  padding: 0.85rem 1rem;
  border: 1px solid var(--hair);
  border-radius: var(--r-sm);
  background: var(--white);
  font-size: 0.94rem;
}
.record-row:hover { border-color: rgba(15, 107, 122, 0.34); }
@media (max-width: 640px) {
  .record-row { grid-template-columns: minmax(0, 1fr) auto; gap: 0.4rem 0.8rem; }
}

.compare { display: grid; grid-template-columns: 1fr 1fr; gap: clamp(0.7rem, 1.6vw, 1.2rem); }
.compare__side {
  padding: clamp(1rem, 2vw, 1.5rem);
  border: 1px solid var(--hair);
  border-radius: var(--r-md);
  background: var(--white);
}
.compare__side--before { background: var(--haze); border-color: var(--hair-soft); }
.compare__side--after { border-color: rgba(15, 107, 122, 0.3); }
.compare__label {
  display: block;
  margin-bottom: 0.5rem;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.14em;
  color: var(--teal-deep);
}
.compare__side--before .compare__label { color: var(--gray); }
@media (max-width: 720px) { .compare { grid-template-columns: 1fr; } }

.fold { border-bottom: 1px solid var(--hair); }
.fold__summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 1.05rem 0.2rem;
  cursor: pointer;
  font-family: var(--font-head);
  font-weight: 800;
  font-size: 1rem;
  color: var(--ink);
}
.fold__summary::-webkit-details-marker { display: none; }
.fold__summary::after {
  content: "+";
  font-family: var(--font-mono);
  font-size: 1.1rem;
  color: var(--teal);
  transition: color 0.2s var(--ease);
}
.fold[open] .fold__summary::after { content: "–"; color: var(--sand); }
.fold__body {
  padding: 0 0.2rem 1.2rem;
  font-size: 0.98rem;
  line-height: 1.85;
  color: var(--ink-80);
}

.tabs__list {
  display: flex;
  flex-wrap: wrap;
  gap: 0.35rem;
  width: max-content;
  max-width: 100%;
  padding: 0.3rem;
  border-radius: var(--r-pill);
  background: var(--haze);
}
.tabs__tab {
  padding: 0.5rem 1.1rem;
  border-radius: var(--r-pill);
  font-family: var(--font-head);
  font-weight: 700;
  font-size: 0.88rem;
  color: var(--ink-60);
  transition: background 0.2s var(--ease), color 0.2s var(--ease);
}
.tabs__tab:hover { color: var(--teal-deep); }
.tabs__tab[aria-selected="true"] {
  background: var(--white);
  color: var(--teal-deep);
  box-shadow: 0 4px 12px -8px rgba(12, 27, 32, 0.5);
}
.tabs__panel { margin-top: 1.4rem; }
.tabs__panel[hidden] { display: none; }

.media-frame {
  position: relative;
  isolation: isolate;
  overflow: hidden;
  border-radius: var(--r-md);
  background: var(--haze);
}
.media-frame::after {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(12, 27, 32, 0.07) 1px, transparent 1px),
    linear-gradient(90deg, rgba(12, 27, 32, 0.07) 1px, transparent 1px);
  background-size: 40px 40px;
  mix-blend-mode: multiply;
  pointer-events: none;
}
.media-frame img,
.media-frame svg {
  width: 100%;
  height: 100%;
  object-fit: cover;
}
.media-frame--band { aspect-ratio: 21 / 9; }
.media-frame--wide { aspect-ratio: 16 / 9; }
.media-frame--portrait { aspect-ratio: 4 / 5; }
.media-caption {
  margin-top: 0.6rem;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.08em;
  color: var(--gray);
}

.toc {
  position: sticky;
  top: 1.2rem;
  padding-left: 1rem;
  border-left: 2px solid var(--haze);
}
.toc__title {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.16em;
  color: var(--gray);
}
.toc__list { display: grid; gap: 0.45rem; margin-top: 0.8rem; }
.toc__link {
  display: block;
  padding: 0.15rem 0;
  font-family: var(--font-head);
  font-size: 0.86rem;
  font-weight: 600;
  color: var(--ink-60);
  transition: color 0.2s var(--ease);
}
.toc__link:hover { color: var(--teal-deep); }
.toc__link[aria-current] { color: var(--teal-deep); font-weight: 800; }
.toc__link[aria-current]::before { content: "▸ "; color: var(--sand); }

/* 滚动进度 */
.read-progress {
  position: fixed;
  top: 0;
  left: 0;
  z-index: 120;
  width: 100%;
  height: 3px;
  background: linear-gradient(90deg, var(--teal), var(--sand));
  transform: scaleX(0);
  transform-origin: 0 50%;
  pointer-events: none;
}

/* 渐显 */
[data-reveal] {
  opacity: 0;
  transform: translateY(14px);
  transition: opacity 0.6s var(--ease), transform 0.6s var(--ease);
}
[data-reveal].is-visible { opacity: 1; transform: none; }

/* ---------- 减少动效 ---------- */
@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;
  }
  [data-reveal] { opacity: 1; transform: none; }
}