/* ==========================================================================
   大红鹰登录网址 · 共享样式 /assets/site.css
   单色排版建筑：只用字号、字重与空间建层级；无边框、无阴影、无圆角
   ========================================================================== */

/* --- 1. 设计定稿变量 ------------------------------------------------ */
:root {
  --color-surface: #f8f8f8;
  --color-surface-alt: #efeff0;
  --color-surface-deep: #e3e3e4;
  --color-ink: #484851;
  --color-ink-soft: #6d6d79;
  --color-ink-muted: #7a7a85;
  --color-line: #d8d8da;
  --color-primary: #747382;
  --color-primary-ink: #ffffff;
  --color-primary-soft: #e6e5e7;
  --color-accent: #221ee1;
  --color-accent-ink: #ffffff;
  --color-highlight: #d1d1f4;
  --color-focus: #1511ee;
  --color-contrast-surface: #17171a;
  --color-contrast-ink: #e4e4e7;
  --color-contrast-line: #444447;
  --color-contrast-accent: #7674ec;
  --overlay-scrim: linear-gradient(180deg, rgba(23, 23, 26, 0.35) 0%, rgba(23, 23, 26, 0.72) 55%, rgba(23, 23, 26, 0.92) 100%);
  --font-heading: STZhongsong, "Source Han Serif SC", "Songti SC", SimSun, serif;
  --font-body: "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-mono: ui-monospace, Menlo, Consolas, monospace;
  --text-xs: 10.7px;
  --text-sm: 15.1px;
  --text-base: 18px;
  --text-lg: 25.5px;
  --text-xl: 36.0px;
  --text-2xl: 50.9px;
  --text-3xl: 72.0px;
  --text-4xl: 101.7px;
  --text-display: clamp(52px, 10.6vw, 136px);
  --text-figure: clamp(43px, 7.7vw, 98px);
  --weight-heading: 508;
  --weight-body: 400;
  --leading-body: 1.76;
  --leading-heading: 1.16;
  --tracking-heading: 0.005em;
  --radius-sm: 0px;
  --radius-md: 0px;
  --radius-lg: 0px;
  --radius-pill: 0px;
  --border-thin: 1px;
  --border-thick: 1px;
  --shadow-1: none;
  --shadow-2: none;
  --space-1: 8px;
  --space-2: 16px;
  --space-3: 24px;
  --space-4: 32px;
  --space-6: 48px;
  --space-8: 64px;
  --container: 1100px;
  --measure: 61ch;
  --gutter: 24px;
  --section-y: 130px;
  --section-y-lg: 182px;
}

/* --- 2. Reset -------------------------------------------------------- */
*,
*::before,
*::after { box-sizing: border-box; }

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
  scroll-padding-top: 112px;
}

body {
  margin: 0;
  background-color: var(--color-surface);
  color: var(--color-ink);
  font-family: var(--font-body);
  font-size: var(--text-base);
  font-weight: var(--weight-body);
  line-height: var(--leading-body);
  letter-spacing: 0.012em;
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3, h4, h5, h6 {
  margin: 0;
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  line-height: var(--leading-heading);
  letter-spacing: var(--tracking-heading);
  color: inherit;
  text-wrap: balance;
}

p { margin: 0; }
ul, ol { margin: 0; padding: 0; list-style: none; }
figure { margin: 0; }
img, svg { max-width: 100%; }
img { height: auto; }
button { font: inherit; color: inherit; }
address { font-style: normal; }
table { border-collapse: collapse; }

a {
  color: var(--color-ink);
  text-decoration: none;
  transition: color 150ms ease, text-decoration-color 150ms ease;
}
a:hover,
a:focus-visible { color: var(--color-accent); }

::selection {
  background-color: var(--color-highlight);
  color: var(--color-ink);
}

:focus-visible {
  outline: 2px solid var(--color-focus);
  outline-offset: 3px;
  border-radius: 0;
}

[hidden] { display: none !important; }

/* --- 3. 布局基础 ----------------------------------------------------- */
.shell {
  width: 100%;
  max-width: var(--container);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.section { padding-block: var(--section-y); }
.section--tight { padding-block: var(--space-8); }
.section--lg { padding-block: var(--section-y-lg); }

.section--alt { background-color: var(--color-surface-alt); }
.section--deep { background-color: var(--color-surface-deep); }

.section--contrast {
  background-color: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
}
.section--contrast a { color: var(--color-contrast-ink); }
.section--contrast a:hover,
.section--contrast a:focus-visible { color: var(--color-contrast-accent); }
.section--contrast :focus-visible { outline-color: var(--color-contrast-accent); }

.section-head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: var(--space-2) var(--space-4);
  margin-bottom: var(--space-6);
}
.section-head .more { margin-left: auto; }

/* 栅格 */
.grid {
  display: grid;
  gap: var(--space-6) var(--gutter);
}
.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)); }

.split {
  display: grid;
  grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
  gap: var(--gutter);
  align-items: start;
}
.split--wide { grid-template-columns: minmax(0, 8fr) minmax(0, 4fr); }
.split--flip { grid-template-columns: minmax(0, 5fr) minmax(0, 7fr); }

.stack { display: grid; gap: var(--space-3); }
.stack--lg { display: grid; gap: var(--space-6); }

/* --- 4. 排版层级 ----------------------------------------------------- */
.eyebrow {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.24em;
  text-transform: uppercase;
  color: var(--color-ink-muted);
}
.section--contrast .eyebrow {
  color: color-mix(in srgb, var(--color-contrast-ink) 58%, var(--color-contrast-surface));
}

.display {
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--text-display);
  line-height: 1.02;
  letter-spacing: -0.005em;
}

.page-title {
  font-size: var(--text-3xl);
  line-height: 1.1;
}

.section-title { font-size: var(--text-xl); }
.sub-title { font-size: var(--text-lg); }

.lede {
  max-width: var(--measure);
  font-size: var(--text-lg);
  line-height: 1.55;
  color: var(--color-ink-soft);
}
.section--contrast .lede {
  color: color-mix(in srgb, var(--color-contrast-ink) 82%, var(--color-contrast-surface));
}

.figure {
  display: block;
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--text-figure);
  line-height: 1;
  letter-spacing: -0.01em;
}

.figure-label {
  display: block;
  margin-top: var(--space-2);
  font-size: var(--text-sm);
  color: var(--color-ink-muted);
}

.prose {
  max-width: var(--measure);
}
.prose > * + * { margin-top: var(--space-3); }
.prose h2 {
  margin-top: var(--space-8);
  font-size: var(--text-xl);
}
.prose h3 {
  margin-top: var(--space-6);
  font-size: var(--text-lg);
}
.prose li {
  position: relative;
  padding-left: var(--space-4);
}
.prose ul > li + li,
.prose ol > li + li { margin-top: var(--space-2); }
.prose ul > li::before {
  content: "—";
  position: absolute;
  left: 0;
  color: var(--color-ink-muted);
}
.prose a {
  color: var(--color-ink);
  text-decoration-line: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 6px;
  text-decoration-color: color-mix(in srgb, var(--color-ink) 35%, transparent);
}
.prose a:hover,
.prose a:focus-visible {
  color: var(--color-accent);
  text-decoration-color: currentColor;
}

.note {
  max-width: 46ch;
  padding-left: var(--space-3);
  font-size: var(--text-sm);
  line-height: 1.72;
  color: var(--color-ink-soft);
}

.quote {
  max-width: var(--measure);
  padding: var(--space-4);
  background-color: var(--color-highlight);
  color: var(--color-ink);
  font-size: var(--text-lg);
  line-height: 1.5;
}

/* --- 5. 链接与行动入口 ----------------------------------------------- */
.link {
  color: var(--color-ink);
  text-decoration-line: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 6px;
  text-decoration-color: color-mix(in srgb, var(--color-ink) 35%, transparent);
}
.link:hover,
.link:focus-visible {
  color: var(--color-accent);
  text-decoration-color: currentColor;
}

.cta,
.more {
  display: inline-flex;
  align-items: baseline;
  gap: 0.4em;
  font-size: var(--text-sm);
  font-weight: 700;
  letter-spacing: 0.06em;
  color: var(--color-ink);
  text-decoration-line: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 6px;
  text-decoration-color: color-mix(in srgb, var(--color-ink) 35%, transparent);
}
.cta:hover,
.cta:focus-visible,
.more:hover,
.more:focus-visible {
  color: var(--color-accent);
  text-decoration-thickness: 2px;
  text-decoration-color: currentColor;
}
.section--contrast .cta,
.section--contrast .more { color: var(--color-contrast-ink); }

/* 面包屑 */
.breadcrumbs {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-1);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.12em;
  color: var(--color-ink-muted);
}
.breadcrumbs li { display: inline-flex; align-items: baseline; gap: var(--space-1); }
.breadcrumbs li::after {
  content: "/";
  color: color-mix(in srgb, var(--color-ink-muted) 55%, transparent);
}
.breadcrumbs li:last-child::after { content: none; }
.breadcrumbs a { color: var(--color-ink-soft); }
.breadcrumbs a:hover,
.breadcrumbs a:focus-visible { color: var(--color-accent); }

/* --- 6. 头部：紧凑命令栏 --------------------------------------------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 60;
  background-color: var(--color-surface);
  color: var(--color-ink);
}

.header-inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: var(--space-4);
  padding-block: var(--space-3);
}

.brand {
  display: inline-flex;
  align-items: baseline;
  gap: var(--space-2);
  flex: 0 0 auto;
  color: var(--color-ink);
}
.brand-name {
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--text-lg);
  letter-spacing: 0.03em;
  line-height: 1;
}
.brand-tag {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.22em;
  color: var(--color-ink-muted);
}
.brand:hover .brand-name,
.brand:focus-visible .brand-name { color: var(--color-accent); }

.site-nav { margin-left: auto; }

.nav-index {
  display: flex;
  align-items: baseline;
  gap: var(--space-4);
}
.nav-index a {
  display: inline-flex;
  align-items: baseline;
  gap: 6px;
  padding-block: 2px;
  font-size: var(--text-sm);
  color: var(--color-ink);
  white-space: nowrap;
}
.nav-index a:hover,
.nav-index a:focus-visible { color: var(--color-accent); }
.nav-index a[aria-current="page"] {
  color: var(--color-accent);
  text-decoration-line: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 6px;
  text-decoration-color: currentColor;
}
.nav-num {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.1em;
  color: var(--color-ink-muted);
}
.nav-index a:hover .nav-num,
.nav-index a[aria-current="page"] .nav-num { color: var(--color-accent); }

.header-cta {
  flex: 0 0 auto;
  font-size: var(--text-sm);
  font-weight: 700;
  letter-spacing: 0.08em;
  color: var(--color-ink);
  text-decoration-line: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 6px;
  text-decoration-color: color-mix(in srgb, var(--color-ink) 35%, transparent);
}
.header-cta:hover,
.header-cta:focus-visible {
  color: var(--color-accent);
  text-decoration-thickness: 2px;
  text-decoration-color: currentColor;
}

.nav-toggle {
  display: none;
  align-items: center;
  margin-left: auto;
  padding: var(--space-1) 0;
  border: 0;
  background: none;
  font-size: var(--text-sm);
  font-weight: 700;
  letter-spacing: 0.1em;
  color: var(--color-ink);
  cursor: pointer;
}
.nav-toggle:hover,
.nav-toggle:focus-visible { color: var(--color-accent); }
.nav-toggle[aria-expanded="true"] {
  color: var(--color-accent);
  text-decoration-line: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 6px;
  text-decoration-color: currentColor;
}

/* 跳转链接 */
.skip-link {
  position: absolute;
  left: var(--space-3);
  top: -6rem;
  z-index: 80;
  padding: var(--space-2) var(--space-3);
  font-size: var(--text-sm);
  background-color: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  transition: top 160ms ease;
}
.skip-link:focus {
  top: var(--space-2);
  color: var(--color-contrast-accent);
}

/* --- 7. 页脚：反色 --------------------------------------------------- */
.site-footer {
  margin-top: var(--section-y);
  padding-block: var(--section-y) var(--space-6);
  background-color: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
}
.site-footer a { color: var(--color-contrast-ink); }
.site-footer a:hover,
.site-footer a:focus-visible { color: var(--color-contrast-accent); }
.site-footer :focus-visible { outline-color: var(--color-contrast-accent); }

.footer-lead {
  display: grid;
  gap: var(--space-3);
  padding-bottom: var(--space-8);
}

.footer-brand {
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--text-2xl);
  line-height: var(--leading-heading);
  letter-spacing: 0.02em;
  color: var(--color-contrast-ink);
}

.footer-line {
  max-width: var(--measure);
  font-size: var(--text-sm);
  line-height: 1.7;
  color: color-mix(in srgb, var(--color-contrast-ink) 62%, var(--color-contrast-surface));
}

.footer-cols {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: var(--space-6) var(--space-4);
  padding-bottom: var(--space-8);
}

.footer-col { display: grid; align-content: start; gap: var(--space-3); }

.footer-col-title {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  font-weight: var(--weight-body);
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: color-mix(in srgb, var(--color-contrast-ink) 52%, var(--color-contrast-surface));
}

.footer-list { display: grid; gap: var(--space-2); }
.footer-list a { font-size: var(--text-sm); }

.footer-text {
  display: block;
  font-size: var(--text-sm);
  line-height: 1.7;
  color: color-mix(in srgb, var(--color-contrast-ink) 72%, var(--color-contrast-surface));
}
.footer-address { display: grid; gap: var(--space-1); }
.footer-note { margin-top: var(--space-2); }

.footer-legal {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2) var(--space-4);
  padding-top: var(--space-4);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.1em;
  color: color-mix(in srgb, var(--color-contrast-ink) 56%, var(--color-contrast-surface));
}

/* --- 8. 条目、筛选与目录 --------------------------------------------- */
.filter-bar {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: var(--space-2) var(--space-3);
  margin-bottom: var(--space-6);
}
.filter-bar__label {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--color-ink-muted);
}
.filter-btn {
  padding: var(--space-1) var(--space-2);
  border: 0;
  border-radius: var(--radius-sm);
  background-color: transparent;
  font-size: var(--text-sm);
  color: var(--color-ink);
  cursor: pointer;
  transition: background-color 150ms ease, color 150ms ease;
}
.filter-btn:hover { color: var(--color-accent); }
.filter-btn.is-active,
.filter-btn[aria-pressed="true"] {
  background-color: var(--color-primary-soft);
  color: var(--color-accent);
}
.filter-count,
.filter-empty {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.12em;
  color: var(--color-ink-muted);
}
.filter-empty { font-family: var(--font-body); font-size: var(--text-sm); color: var(--color-ink-soft); }

.entry-list { display: grid; gap: var(--space-8); }
.entry-list--dense { gap: var(--space-6); }

.entry { display: grid; align-content: start; gap: var(--space-2); }
.entry__title { font-size: var(--text-lg); }
.entry__meta {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.14em;
  color: var(--color-ink-muted);
}
.entry__body { font-size: var(--text-base); color: var(--color-ink-soft); }
.entry a:hover .entry__title,
.entry a:focus-visible .entry__title { color: var(--color-accent); }

.toc { display: grid; gap: var(--space-2); }
.toc-title {
  margin-bottom: var(--space-1);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.2em;
  color: var(--color-ink-muted);
}
.toc a {
  padding-left: var(--space-3);
  font-size: var(--text-sm);
  color: var(--color-ink-soft);
}
.toc a:hover,
.toc a:focus-visible { color: var(--color-accent); }
.toc a.is-current {
  color: var(--color-accent);
  font-weight: 700;
}

/* --- 9. 图片背景与数据条 --------------------------------------------- */
.media {
  position: relative;
  display: block;
  overflow: hidden;
  background-color: var(--color-surface-deep);
}
.media img { display: block; width: 100%; height: 100%; object-fit: cover; }
.media__scrim {
  position: absolute;
  inset: 0;
  background-image: var(--overlay-scrim);
}
.media__body {
  position: absolute;
  inset: auto 0 0 0;
  padding: var(--space-6);
  color: var(--color-contrast-ink);
}
.media__body a { color: var(--color-contrast-ink); }
.media__body a:hover,
.media__body a:focus-visible { color: var(--color-contrast-accent); }

.media--16x9 { aspect-ratio: 16 / 9; }
.media--21x9 { aspect-ratio: 21 / 9; }
.media--1x1 { aspect-ratio: 1 / 1; }
.media--4x5 { aspect-ratio: 4 / 5; }

.data-bar { display: grid; gap: var(--space-3); }
.data-bar__row {
  display: grid;
  grid-template-columns: minmax(0, 7rem) minmax(0, 1fr) auto;
  gap: var(--space-3);
  align-items: center;
  font-size: var(--text-sm);
}
.data-bar__track {
  height: 14px;
  background-color: var(--color-surface-deep);
}
.data-bar__fill {
  display: block;
  height: 100%;
  width: var(--value, 0%);
  background-color: var(--color-primary);
}
.data-bar__value {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.08em;
  color: var(--color-ink-soft);
}
.section--contrast .data-bar__track { background-color: var(--color-contrast-line); }
.section--contrast .data-bar__value { color: var(--color-contrast-ink); }

/* --- 10. 对照表（全站唯一允许细线的位置） ---------------------------- */
.table-scroll { overflow-x: auto; }

.spec-table {
  width: 100%;
  min-width: 620px;
  font-size: var(--text-sm);
}
.spec-table caption {
  margin-bottom: var(--space-3);
  text-align: left;
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.2em;
  color: var(--color-ink-muted);
}
.spec-table th,
.spec-table td {
  padding: var(--space-3) var(--space-3) var(--space-3) 0;
  text-align: left;
  vertical-align: top;
  border-bottom: var(--border-thin) solid var(--color-line);
}
.spec-table thead th {
  padding-left: var(--space-3);
  background-color: var(--color-surface-deep);
  color: var(--color-ink);
  font-weight: 700;
}
.spec-table tbody th { color: var(--color-ink); font-weight: 700; white-space: nowrap; }
.spec-table tbody td { color: var(--color-ink-soft); }

/* --- 11. 显现与工具类 ------------------------------------------------ */
.has-js [data-reveal] {
  opacity: 0;
  transform: translateY(8px);
}
.has-js [data-reveal].is-in {
  opacity: 1;
  transform: none;
  transition: opacity 200ms ease, transform 200ms ease;
}

.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;
}

/* --- 12. 响应式 ------------------------------------------------------ */
@media (max-width: 1024px) {
  :root { --section-y: 104px; --section-y-lg: 138px; }
  .footer-cols { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 900px) {
  .grid-2,
  .grid-3,
  .grid-4,
  .split,
  .split--wide,
  .split--flip { grid-template-columns: minmax(0, 1fr); }

  .header-inner { gap: var(--space-2) var(--space-3); }

  .brand { order: 1; }
  .brand-name { font-size: var(--text-base); }
  .brand-tag { display: none; }

  .header-cta { order: 2; margin-left: auto; }
  .nav-toggle { order: 3; display: inline-flex; }

  .site-nav {
    order: 4;
    display: none;
    flex: 1 0 100%;
    margin-left: 0;
    padding-top: var(--space-2);
    overflow-x: auto;
    overflow-y: hidden;
    -webkit-overflow-scrolling: touch;
    scrollbar-width: none;
    scroll-snap-type: x proximity;
  }
  .site-nav::-webkit-scrollbar { display: none; }
  .site-nav[data-open] { display: block; }

  .nav-index {
    flex-wrap: nowrap;
    width: max-content;
    gap: var(--space-4);
    padding-bottom: var(--space-1);
  }
  .nav-index li { scroll-snap-align: start; }

  .footer-cols { gap: var(--space-6) var(--gutter); }
  .footer-brand { font-size: var(--text-xl); }

  .media--16x9,
  .media--21x9 { aspect-ratio: 4 / 3; }
  .media__body { padding: var(--space-4); }

  .data-bar__row {
    grid-template-columns: minmax(0, 1fr) auto;
    grid-template-areas: "label value" "track track";
    row-gap: var(--space-1);
  }
  .data-bar__row > :first-child { grid-area: label; }
  .data-bar__track { grid-area: track; }
  .data-bar__value { grid-area: value; }
}

@media (max-width: 560px) {
  :root { --section-y: 80px; --section-y-lg: 104px; }
  .footer-cols { grid-template-columns: minmax(0, 1fr); }
  .footer-brand { font-size: var(--text-lg); }
  .header-cta { font-size: var(--text-xs); letter-spacing: 0.04em; }
}

/* --- 13. 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;
  }
  .has-js [data-reveal] {
    opacity: 1;
    transform: none;
  }
}