/* =========================================================
   博业主站 · /assets/site.css
   共享外壳：reset / 变量 / 中文排版 / 框架导航 / 页脚 / 通用组件
   ========================================================= */

/* ---------- 01 Reset ---------- */
*,
*::before,
*::after { box-sizing: border-box; }

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

body,
h1, h2, h3, h4, p, ul, ol, li, figure, blockquote { margin: 0; padding: 0; }

ul, ol { list-style: none; }

a { color: inherit; text-decoration: none; }

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

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

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

:where(a, button, [tabindex], input):focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 2px;
}

/* ---------- 02 变量 ---------- */
:root {
  --ink: #06080C;
  --navy: #0B1420;
  --slate: #16222F;
  --line: #2A3746;
  --white: #F4F7FA;
  --fog: #93A3B2;
  --cyan: #21E6D6;
  --orange: #FF7A29;
  --gold: #E4B23C;
  --cold: #3D7BFF;
  --hot: #FF4D5F;
  --paper: rgba(233, 237, 242, 0.06);
  --paper-strong: rgba(233, 237, 242, 0.10);

  --rail: 88px;
  --maxw: 1360px;
  --gutter: clamp(20px, 4vw, 56px);

  --font-head: "Noto Sans SC", "Source Han Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-body: "Noto Sans SC", "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", sans-serif;
  --font-mono: "JetBrains Mono", "IBM Plex Mono", ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;

  --step: 160ms;
  --ease: cubic-bezier(0.2, 0.6, 0.2, 1);
}

/* ---------- 03 中文排版与页面基底 ---------- */
body {
  background: var(--ink);
  color: var(--white);
  font-family: var(--font-body);
  font-size: 17px;
  font-weight: 400;
  line-height: 1.9;
  letter-spacing: 0.01em;
  padding-left: var(--rail);
  padding-bottom: 0;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

h1, h2, h3, h4 {
  font-family: var(--font-head);
  font-weight: 900;
  line-height: 1.28;
  letter-spacing: 0.01em;
}

.mono {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  letter-spacing: 0.06em;
}

.hairline {
  height: 1px;
  border: 0;
  background: var(--line);
  margin: 0;
}

/* ---------- 04 跳转链接 ---------- */
.skip-link {
  position: fixed;
  top: 8px;
  left: calc(var(--rail) + 12px);
  z-index: 200;
  padding: 9px 16px;
  background: var(--cyan);
  color: var(--ink);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.12em;
  transform: translateY(-260%);
  transition: transform var(--step) var(--ease);
}

.skip-link:focus {
  transform: translateY(0);
}

/* ---------- 05 框架式页头（桌面竖栏） ---------- */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  bottom: 0;
  width: var(--rail);
  z-index: 90;
  background: var(--ink);
  border-right: 1px solid var(--line);
  display: flex;
  flex-direction: column;
}

.header-rail {
  flex: 1;
  min-height: 0;
  display: flex;
  flex-direction: column;
  overflow-y: auto;
  overscroll-behavior: contain;
}

.rail-top {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 18px;
  padding: 28px 0 20px;
  border-bottom: 1px solid var(--line);
}

.brand {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
}

.brand__mark {
  writing-mode: vertical-rl;
  font-family: var(--font-head);
  font-size: 21px;
  font-weight: 900;
  letter-spacing: 0.16em;
  line-height: 1;
  color: var(--white);
}

.brand__tagline {
  writing-mode: vertical-rl;
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.2em;
  line-height: 1;
  color: var(--fog);
}

.nav-toggle {
  display: none;
  align-items: center;
  gap: 9px;
  padding: 8px 4px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--fog);
}

.nav-toggle__icon {
  display: block;
  width: 15px;
  height: 1px;
  background: currentColor;
  box-shadow: 0 4px 0 currentColor;
}

.nav-toggle[aria-expanded="true"] {
  color: var(--cyan);
}

.rail-panel {
  flex: 1;
  min-height: 0;
  display: flex;
  flex-direction: column;
}

.rail-nav {
  padding: 26px 0;
}

.rail-nav__list {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 13px;
}

.rail-nav__link {
  position: relative;
  display: inline-block;
  writing-mode: vertical-rl;
  padding: 6px 9px;
  font-family: var(--font-body);
  font-size: 12.5px;
  font-weight: 500;
  letter-spacing: 0.16em;
  color: var(--fog);
  transition: color var(--step) var(--ease), background-color var(--step) var(--ease);
}

.rail-nav__link:hover {
  color: var(--white);
  background: rgba(244, 247, 250, 0.03);
}

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

.rail-nav__link[aria-current="page"]::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 2px;
  background: var(--cyan);
}

.rail-foot {
  margin-top: auto;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 18px;
  padding: 18px 0 22px;
  border-top: 1px solid var(--line);
}

.rail-cta {
  writing-mode: vertical-rl;
  padding: 12px 7px;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.16em;
  color: var(--cyan);
  border: 1px solid rgba(33, 230, 214, 0.42);
  transition: background-color var(--step) var(--ease), border-color var(--step) var(--ease);
}

.rail-cta:hover {
  background: rgba(33, 230, 214, 0.08);
  border-color: var(--cyan);
}

.rail-utility {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
}

.rail-utility__link {
  writing-mode: vertical-rl;
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: 0.16em;
  color: var(--fog);
  transition: color var(--step) var(--ease);
}

.rail-utility__link:hover { color: var(--white); }

.rail-status {
  width: 100%;
  padding: 0 10px;
  font-family: var(--font-mono);
  font-size: 9px;
  line-height: 1.75;
  letter-spacing: 0.08em;
  text-align: center;
  color: rgba(147, 163, 178, 0.68);
}

/* 阅读进度条 */
.scroll-progress {
  position: fixed;
  top: 0;
  left: var(--rail);
  right: 0;
  height: 2px;
  z-index: 120;
  background: var(--cyan);
  transform: scaleX(0);
  transform-origin: left center;
  pointer-events: none;
}

/* 移动端快捷条（桌面隐藏） */
.quickbar { display: none; }

/* ---------- 06 页脚 ---------- */
.site-footer {
  background: var(--navy);
  border-top: 1px solid var(--line);
  color: var(--fog);
  font-size: 15px;
}

.footer-inner {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: clamp(40px, 6vw, 76px) var(--gutter) 0;
}

.footer-top {
  display: grid;
  grid-template-columns: 1.1fr 3fr;
  gap: clamp(24px, 4vw, 64px);
  padding-bottom: clamp(32px, 4vw, 48px);
  border-bottom: 1px solid var(--line);
}

.footer-brand__mark {
  font-family: var(--font-head);
  font-size: 24px;
  font-weight: 900;
  letter-spacing: 0.08em;
  color: var(--white);
  line-height: 1.2;
}

.footer-brand__tagline {
  margin-top: 10px;
  font-size: 13px;
  line-height: 1.8;
  letter-spacing: 0.04em;
  color: var(--fog);
}

.footer-brand__ver {
  margin-top: 14px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  color: var(--cyan);
}

.footer-cols {
  display: grid;
  grid-template-columns: repeat(3, 1fr) 1.7fr;
  gap: clamp(18px, 3vw, 42px);
}

.footer-col__title {
  margin-bottom: 14px;
  font-family: var(--font-mono);
  font-size: 11.5px;
  font-weight: 500;
  letter-spacing: 0.14em;
  color: var(--fog);
}

.footer-links {
  display: flex;
  flex-direction: column;
  gap: 9px;
}

.footer-link {
  font-size: 14.5px;
  letter-spacing: 0.03em;
  color: var(--white);
  transition: color var(--step) var(--ease);
}

.footer-link:hover { color: var(--cyan); }

.footer-contact {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.footer-contact__row {
  display: grid;
  grid-template-columns: 46px 1fr;
  gap: 10px;
  align-items: baseline;
}

.footer-contact__label {
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: 0.14em;
  color: var(--fog);
}

.footer-contact__value {
  font-size: 14px;
  line-height: 1.75;
  color: var(--white);
}

.copy-btn {
  justify-self: start;
  padding: 0 0 2px;
  font-family: var(--font-mono);
  font-size: 13.5px;
  letter-spacing: 0.04em;
  color: var(--white);
  text-align: left;
  border-bottom: 1px solid var(--line);
  transition: color var(--step) var(--ease), border-color var(--step) var(--ease);
}

.copy-btn:hover {
  color: var(--cyan);
  border-color: rgba(33, 230, 214, 0.5);
}

.copy-btn[data-copied] {
  color: var(--cyan);
  border-color: var(--cyan);
}

.footer-note {
  padding: 24px 0;
  max-width: 74ch;
  font-size: 13.5px;
  line-height: 1.9;
  color: var(--fog);
  border-bottom: 1px solid var(--line);
}

.footer-bottom {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px 28px;
  margin: 0 calc(-1 * var(--gutter));
  padding: 20px var(--gutter) 26px;
  background: var(--paper);
  border-top: 1px solid var(--line);
}

.footer-legal {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--fog);
}

.footer-copy {
  font-size: 12.5px;
  color: var(--fog);
}

.footer-year {
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.12em;
  color: rgba(147, 163, 178, 0.82);
}

/* ---------- 07 通用组件 ---------- */
.wrap {
  width: 100%;
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 0 var(--gutter);
}

.section {
  padding: clamp(48px, 7vw, 96px) 0;
}

.section--navy { background: var(--navy); }
.section--slate { background: var(--slate); }

.section-head {
  display: flex;
  align-items: baseline;
  gap: 16px;
  padding-bottom: 14px;
  margin-bottom: clamp(28px, 4vw, 44px);
  border-bottom: 1px solid var(--line);
}

.section-index {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--cyan);
}

.section-title {
  font-size: clamp(22px, 2.4vw, 26px);
  font-weight: 900;
}

.lede {
  max-width: 62ch;
  font-size: 18px;
  line-height: 1.9;
  color: var(--fog);
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 13px 22px;
  border: 1px solid var(--line);
  font-size: 14px;
  font-weight: 500;
  letter-spacing: 0.08em;
  color: var(--white);
  background: transparent;
  transition: color var(--step) var(--ease), border-color var(--step) var(--ease), background-color var(--step) var(--ease);
}

.btn:hover {
  border-color: var(--fog);
  background: rgba(244, 247, 250, 0.03);
}

.btn--primary {
  color: var(--cyan);
  border-color: rgba(33, 230, 214, 0.5);
}

.btn--primary:hover {
  border-color: var(--cyan);
  background: rgba(33, 230, 214, 0.08);
}

.tag {
  display: inline-block;
  padding: 4px 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--fog);
  background: var(--paper);
  border: 1px solid var(--line);
}

.tag--cyan { color: var(--cyan); border-color: rgba(33, 230, 214, 0.45); }
.tag--orange { color: var(--orange); border-color: rgba(255, 122, 41, 0.45); }
.tag--gold { color: var(--gold); border-color: rgba(228, 178, 60, 0.45); }

.breadcrumb {
  padding: 16px 0;
  border-bottom: 1px solid var(--line);
}

.breadcrumb__list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--fog);
}

.breadcrumb__item {
  display: flex;
  align-items: center;
  gap: 8px;
}

.breadcrumb__item + .breadcrumb__item::before {
  content: "/";
  color: var(--line);
}

.breadcrumb__link {
  transition: color var(--step) var(--ease);
}

.breadcrumb__link:hover { color: var(--white); }

.breadcrumb__current { color: var(--fog); }

.prose {
  max-width: 62ch;
  font-size: 17px;
  line-height: 1.9;
}

.prose > * + * { margin-top: 1.5em; }

.prose h2 {
  font-size: clamp(20px, 2vw, 24px);
  font-weight: 900;
}

.prose h3 {
  font-size: 17px;
  font-weight: 700;
}

.prose a {
  color: var(--cyan);
  border-bottom: 1px solid rgba(33, 230, 214, 0.4);
}

.prose strong { font-weight: 700; color: var(--white); }

.grid {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: 24px;
}

.col-3 { grid-column: span 3; }
.col-4 { grid-column: span 4; }
.col-5 { grid-column: span 5; }
.col-7 { grid-column: span 7; }
.col-8 { grid-column: span 8; }
.col-9 { grid-column: span 9; }
.col-12 { grid-column: span 12; }

.media-frame {
  position: relative;
  width: 100%;
  aspect-ratio: 16 / 9;
  background: var(--slate);
  border: 1px solid var(--line);
  overflow: hidden;
}

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

.media-frame__label {
  position: absolute;
  left: 0;
  bottom: 0;
  padding: 6px 10px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--fog);
  background: rgba(6, 8, 12, 0.76);
  border-top: 1px solid var(--line);
  border-right: 1px solid var(--line);
}

.media-frame--wide { aspect-ratio: 21 / 9; }
.media-frame--square { aspect-ratio: 1 / 1; }
.media-frame--tall { aspect-ratio: 3 / 4; }

/* 显现：无 JS 时保持完全可见 */
.js [data-reveal] {
  opacity: 0;
  transform: translateY(10px);
  transition: opacity var(--step) var(--ease), transform var(--step) var(--ease);
}

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

/* ---------- 08 平板与移动 ---------- */
@media (max-width: 1079px) {
  body {
    padding-left: 0;
    padding-bottom: 62px;
    font-size: 16.5px;
  }

  .skip-link {
    left: 12px;
  }

  .site-header {
    position: sticky;
    top: 0;
    left: auto;
    bottom: auto;
    width: 100%;
    height: 56px;
    z-index: 100;
    border-right: 0;
    border-bottom: 1px solid var(--line);
  }

  .header-rail {
    flex: 0 0 auto;
    height: 56px;
    overflow: visible;
  }

  .rail-top {
    flex-direction: row;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
    height: 56px;
    padding: 0 16px;
    border-bottom: 0;
  }

  .brand {
    flex-direction: row;
    align-items: baseline;
    gap: 10px;
  }

  .brand__mark {
    writing-mode: horizontal-tb;
    font-size: 17px;
    letter-spacing: 0.08em;
  }

  .brand__tagline {
    writing-mode: horizontal-tb;
    font-size: 10px;
    letter-spacing: 0.18em;
  }

  .nav-toggle { display: inline-flex; }

  .rail-panel {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    display: none;
    max-height: calc(100vh - 56px);
    overflow-y: auto;
    background: var(--navy);
    border-bottom: 1px solid var(--line);
    padding-bottom: 18px;
  }

  .site-header[data-open] .rail-panel { display: block; }

  .rail-nav { padding: 0; }

  .rail-nav__list {
    align-items: stretch;
    gap: 0;
  }

  .rail-nav__link {
    writing-mode: horizontal-tb;
    display: block;
    padding: 15px 20px;
    font-size: 16px;
    letter-spacing: 0.06em;
    color: var(--white);
    border-bottom: 1px solid var(--line);
  }

  .rail-nav__link[aria-current="page"] {
    color: var(--cyan);
    box-shadow: inset 2px 0 0 var(--cyan);
  }

  .rail-nav__link[aria-current="page"]::before { display: none; }

  .rail-foot {
    margin-top: 0;
    align-items: stretch;
    gap: 14px;
    padding: 18px 20px 0;
    border-top: 0;
  }

  .rail-cta {
    writing-mode: horizontal-tb;
    padding: 13px 16px;
    text-align: center;
  }

  .rail-utility {
    flex-direction: row;
    gap: 20px;
  }

  .rail-utility__link {
    writing-mode: horizontal-tb;
    font-size: 12px;
  }

  .rail-status {
    width: auto;
    padding: 0;
    font-size: 11px;
    line-height: 1.7;
    text-align: left;
  }

  .scroll-progress {
    position: absolute;
    top: auto;
    bottom: -1px;
    left: 0;
    right: 0;
    height: 2px;
  }

  .quickbar {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    position: fixed;
    left: 0;
    right: 0;
    bottom: 0;
    z-index: 95;
    background: var(--navy);
    border-top: 1px solid var(--line);
    padding-bottom: env(safe-area-inset-bottom, 0);
  }

  .quickbar__link {
    padding: 13px 6px;
    text-align: center;
    font-size: 13px;
    letter-spacing: 0.06em;
    color: var(--fog);
    border-right: 1px solid var(--line);
    transition: color var(--step) var(--ease);
  }

  .quickbar__link:last-child { border-right: 0; }

  .quickbar__link[aria-current="page"] {
    color: var(--cyan);
    box-shadow: inset 0 2px 0 var(--cyan);
  }

  .footer-top {
    grid-template-columns: 1fr;
  }

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

  .col-3, .col-4, .col-5 { grid-column: span 6; }
  .col-7, .col-8, .col-9 { grid-column: span 12; }
}

@media (max-width: 719px) {
  .footer-cols {
    grid-template-columns: 1fr;
    gap: 28px;
  }

  .footer-year { margin-left: 0; }

  .grid { gap: 20px; }

  .col-3, .col-4, .col-5, .col-7, .col-8, .col-9 { grid-column: span 12; }

  .footer-bottom {
    gap: 8px 18px;
  }
}

/* 桌面短视口：压缩竖栏节奏 */
@media (min-width: 1080px) and (max-height: 880px) {
  .rail-top { padding: 18px 0 14px; gap: 12px; }
  .brand__mark { font-size: 19px; }
  .brand__tagline { font-size: 9.5px; }
  .rail-nav { padding: 18px 0; }
  .rail-nav__list { gap: 10px; }
  .rail-nav__link { font-size: 12px; padding: 5px 8px; }
  .rail-foot { padding: 14px 0 16px; gap: 12px; }
  .rail-status { display: none; }
}

/* ---------- 09 降低动态效果 ---------- */
@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;
  }

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