/* ==========================================================================
   36官网旧版 — 共享样式 /assets/site.css
   01 reset · 02 tokens · 03 基础排版 · 04 头部 · 05 页脚 · 06 通用组件
   ========================================================================== */

/* 01 reset ---------------------------------------------------------------- */
*,
*::before,
*::after { box-sizing: border-box; margin: 0; padding: 0; }

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

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

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

a { color: inherit; text-decoration: none; }
ul, ol { list-style: none; }
p, h1, h2, h3, h4 { overflow-wrap: break-word; }

/* 02 tokens --------------------------------------------------------------- */
:root {
  --ink-900: #0B1B2B;
  --ink-800: #12293D;
  --paper: #F2E8D5;
  --paper-2: #E4D5B8;
  --paper-hi: #F7F3EA;
  --signal: #FF6B35;
  --terminal: #3DDC97;
  --terminal-deep: #1F7A57;
  --slate: #8FA3B0;
  --grid: #2F4A5E;
  --warn: #B23A1F;

  --font-display: "Barlow Condensed", "Arial Narrow", "Noto Sans SC", sans-serif;
  --font-body: "Noto Sans SC", "Source Han Sans SC", system-ui, -apple-system, "Segoe UI", sans-serif;
  --font-mono: "IBM Plex Mono", "JetBrains Mono", Menlo, Consolas, monospace;

  --shell: 1180px;
  --shell-narrow: 780px;
  --pad: 1.25rem;
  --dur: .22s;
  --line: 1px solid var(--grid);
}

/* 03 基础排版 ------------------------------------------------------------- */
body {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  font-family: var(--font-body);
  font-size: 17px;
  line-height: 1.75;
  color: var(--paper);
  background-color: var(--ink-900);
  background-image:
    linear-gradient(rgba(47, 74, 94, .16) 1px, transparent 1px),
    linear-gradient(90deg, rgba(47, 74, 94, .16) 1px, transparent 1px);
  background-size: 72px 72px, 72px 72px;
  -webkit-font-smoothing: antialiased;
}

#main-content { display: block; flex: 1 0 auto; }

h1, h2, h3, h4 {
  font-family: var(--font-display);
  font-weight: 800;
  line-height: 1.06;
  letter-spacing: .01em;
  color: var(--paper-hi);
}

h1 { font-size: clamp(2.6rem, 6vw, 5.2rem); line-height: 1.02; }
h2 { font-size: clamp(1.8rem, 3.4vw, 2.6rem); line-height: 1.08; }
h3 { font-size: 1.2rem; font-weight: 700; line-height: 1.24; }
h4 { font-size: 1rem; font-weight: 700; line-height: 1.3; }

p { max-width: 74ch; }

strong { font-weight: 700; color: var(--paper-hi); }

::selection { background: var(--signal); color: var(--ink-900); }

:focus-visible {
  outline: 2px solid var(--signal);
  outline-offset: 2px;
}

/* 04 头部 ----------------------------------------------------------------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 60;
  background: rgba(11, 27, 43, .96);
  border-bottom: var(--line);
  backdrop-filter: blur(6px);
}

.skip-link {
  position: absolute;
  left: 1rem;
  top: -200%;
  z-index: 99;
  padding: .6rem 1rem;
  background: var(--signal);
  color: var(--ink-900);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .1em;
  text-transform: uppercase;
  transition: top var(--dur) ease;
}
.skip-link:focus { top: .8rem; }

/* 状态条 */
.header-rail {
  background: var(--ink-800);
  border-bottom: var(--line);
}
.rail-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  width: 100%;
  max-width: var(--shell);
  margin-inline: auto;
  padding: .4rem var(--pad);
}
.rail-text {
  display: flex;
  align-items: center;
  min-width: 0;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .09em;
  text-transform: uppercase;
  color: var(--slate);
}
.rail-tag {
  flex: 0 0 auto;
  margin-right: .6rem;
  padding: 0 .35rem;
  border: 1px solid rgba(255, 107, 53, .5);
  color: var(--signal);
  font-size: 10px;
}
.brand-line {
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.rail-status {
  display: flex;
  align-items: center;
  gap: .45rem;
  flex: 0 0 auto;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .09em;
  text-transform: uppercase;
  color: var(--slate);
}
.status-dot {
  width: 6px;
  height: 6px;
  background: var(--terminal);
  box-shadow: 0 0 0 3px rgba(61, 220, 151, .16);
}
.status-text { color: var(--slate); }

/* 命令栏主体 */
.header-command { position: relative; }
.command-inner {
  display: flex;
  align-items: center;
  gap: 1rem;
  width: 100%;
  max-width: var(--shell);
  margin-inline: auto;
  padding: .7rem var(--pad);
}

.brand-lockup {
  display: flex;
  align-items: center;
  gap: .7rem;
  flex: 0 0 auto;
}
.brand-mark {
  display: grid;
  place-items: center;
  width: 44px;
  height: 44px;
  background: var(--signal);
  border: 1px solid rgba(11, 27, 43, .4);
  color: var(--ink-900);
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 1.35rem;
  line-height: 1;
  letter-spacing: -.02em;
  transition: background var(--dur) ease, color var(--dur) ease;
}
.brand-lockup:hover .brand-mark,
.brand-lockup:focus-visible .brand-mark {
  background: var(--paper);
  color: var(--ink-900);
}
.brand-text { display: block; }
.brand-name {
  display: block;
  font-family: var(--font-display);
  font-size: 1.15rem;
  font-weight: 800;
  line-height: 1.1;
  letter-spacing: .02em;
  color: var(--paper-hi);
}
.brand-sub {
  display: block;
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: .14em;
  text-transform: uppercase;
  color: var(--slate);
}

/* 导航 */
.site-nav { margin-left: auto; }
.nav-list { display: flex; align-items: stretch; }

.nav-link {
  position: relative;
  display: flex;
  align-items: baseline;
  gap: .4rem;
  padding: .55rem .7rem;
  font-size: .95rem;
  color: var(--paper);
  transition: color var(--dur) ease, background var(--dur) ease;
}
.nav-link::after {
  content: "";
  position: absolute;
  left: .7rem;
  right: .7rem;
  bottom: .25rem;
  height: 1px;
  background: var(--signal);
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform var(--dur) ease;
}
.nav-index {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: .1em;
  color: var(--grid);
  transition: color var(--dur) ease;
}
.nav-label { white-space: nowrap; }

.nav-link:hover,
.nav-link:focus-visible { color: var(--signal); }
.nav-link:hover::after,
.nav-link:focus-visible::after { transform: scaleX(1); }
.nav-link:hover .nav-index,
.nav-link:focus-visible .nav-index { color: var(--signal); }

.nav-link[aria-current="page"] {
  color: var(--paper-hi);
  background: rgba(61, 220, 151, .08);
}
.nav-link[aria-current="page"] .nav-index { color: var(--terminal); }
.nav-link[aria-current="page"]::after {
  background: var(--terminal);
  transform: scaleX(1);
}

.header-actions { flex: 0 0 auto; }

/* 移动端按钮 */
.nav-toggle {
  display: none;
  align-items: center;
  gap: .5rem;
  order: 4;
  padding: .5rem .6rem;
  border: var(--line);
  color: var(--paper);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .12em;
  text-transform: uppercase;
  transition: border-color var(--dur) ease, color var(--dur) ease;
}
.nav-toggle:hover,
.nav-toggle:focus-visible { border-color: var(--terminal); color: var(--terminal); }
.nav-toggle-box { display: grid; gap: 3px; width: 16px; }
.nav-toggle-bar {
  display: block;
  height: 2px;
  background: currentColor;
  transition: transform var(--dur) ease, opacity var(--dur) ease;
}
.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(1) { transform: translateY(5px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(3) { transform: translateY(-5px) rotate(-45deg); }

/* 检索进度扫描线 */
.scroll-progress {
  position: absolute;
  left: 0;
  right: 0;
  bottom: -1px;
  height: 2px;
  background: rgba(47, 74, 94, .55);
  overflow: hidden;
  pointer-events: none;
}
.scroll-progress-bar {
  display: block;
  width: 0;
  height: 100%;
  background: linear-gradient(90deg, var(--signal), var(--terminal));
}

/* 05 页脚 ----------------------------------------------------------------- */
.site-footer {
  position: relative;
  background: var(--ink-900);
  border-top: var(--line);
}

.footer-top {
  padding: clamp(2.2rem, 4vw, 3.4rem) 0 2.6rem;
  background-image:
    linear-gradient(rgba(47, 74, 94, .14) 1px, transparent 1px),
    linear-gradient(90deg, rgba(47, 74, 94, .14) 1px, transparent 1px);
  background-size: 48px 48px, 48px 48px;
}
.footer-grid {
  display: grid;
  grid-template-columns: 1.7fr 1fr 1fr 1fr;
  gap: 2rem 1.75rem;
  width: 100%;
  max-width: var(--shell);
  margin-inline: auto;
  padding-inline: var(--pad);
}
.footer-mark {
  display: inline-grid;
  place-items: center;
  width: 38px;
  height: 38px;
  margin-bottom: .9rem;
  border: 1px solid var(--signal);
  color: var(--signal);
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 1.1rem;
  line-height: 1;
}
.footer-title {
  font-family: var(--font-display);
  font-size: 1.55rem;
  font-weight: 800;
  line-height: 1.1;
  letter-spacing: .02em;
  color: var(--paper-hi);
}
.footer-desc {
  margin-top: .55rem;
  max-width: 34ch;
  font-size: .95rem;
  line-height: 1.7;
  color: var(--slate);
}
.footer-meta {
  display: flex;
  flex-wrap: wrap;
  gap: .4rem;
  margin-top: 1rem;
}
.meta-tag {
  padding: .18rem .45rem;
  border: var(--line);
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--slate);
}

.footer-col-title {
  margin-bottom: .9rem;
  padding-bottom: .5rem;
  border-bottom: var(--line);
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 400;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--terminal);
}
.footer-list { display: grid; gap: .5rem; }
.footer-link {
  display: inline-block;
  font-size: .95rem;
  color: var(--paper);
  background-image: linear-gradient(var(--signal), var(--signal));
  background-repeat: no-repeat;
  background-position: 0 100%;
  background-size: 0% 1px;
  transition: color var(--dur) ease, background-size var(--dur) ease;
}
.footer-link:hover,
.footer-link:focus-visible {
  color: var(--signal);
  background-size: 100% 1px;
}

/* 旧纸联络带 */
.footer-contact-band {
  background: var(--paper);
  color: var(--ink-900);
  border-top: 1px solid var(--paper-2);
  border-bottom: 1px solid var(--paper-2);
}
.contact-inner {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 1rem 2rem;
  width: 100%;
  max-width: var(--shell);
  margin-inline: auto;
  padding: 1.4rem var(--pad);
}
.contact-item {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: .4rem .6rem;
  font-size: .95rem;
}
.contact-label {
  display: block;
  width: 100%;
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: .14em;
  text-transform: uppercase;
  color: #5B6B75;
}
.contact-value {
  color: var(--ink-900);
  font-weight: 600;
  line-height: 1.5;
}
.copy-btn {
  padding: .08rem .4rem;
  border: 1px solid rgba(11, 27, 43, .28);
  color: #3C4A55;
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: .1em;
  text-transform: uppercase;
  transition: background var(--dur) ease, color var(--dur) ease, border-color var(--dur) ease;
}
.copy-btn:hover,
.copy-btn:focus-visible {
  background: var(--ink-900);
  border-color: var(--ink-900);
  color: var(--paper);
}
.copy-status {
  grid-column: 1 / -1;
  min-height: 1.2em;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .08em;
  color: var(--terminal-deep);
}

.footer-legal {
  background: var(--ink-900);
  border-top: var(--line);
}
.legal-inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: .8rem 1.5rem;
  width: 100%;
  max-width: var(--shell);
  margin-inline: auto;
  padding: 1.1rem var(--pad);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .07em;
  color: var(--slate);
}
.legal-note { max-width: 56ch; }
.legal-line {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: .6rem;
}
.legal-icp {
  padding: .15rem .45rem;
  border: var(--line);
  color: var(--paper-2);
}
.legal-sep { color: var(--grid); }

/* 06 通用组件 ------------------------------------------------------------- */
/* 容器与分节 */
.container {
  width: 100%;
  max-width: var(--shell);
  margin-inline: auto;
  padding-inline: var(--pad);
}
.container-narrow {
  width: 100%;
  max-width: var(--shell-narrow);
  margin-inline: auto;
  padding-inline: var(--pad);
}
.section { padding-block: clamp(2.4rem, 5vw, 4.5rem); }
.section-head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: .6rem 1rem;
  margin-bottom: 1.5rem;
}
.section-index {
  padding: .1rem .42rem;
  border: 1px solid rgba(255, 107, 53, .45);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--signal);
}
.section-title {
  font-family: var(--font-display);
  font-size: clamp(1.8rem, 3.2vw, 2.6rem);
  font-weight: 800;
  line-height: 1.06;
  color: var(--paper-hi);
}
.section-note {
  max-width: 62ch;
  font-size: .95rem;
  color: var(--slate);
}

/* 按钮 */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: .45rem;
  padding: .6rem 1rem;
  border: 1px solid transparent;
  font-family: var(--font-mono);
  font-size: 12px;
  line-height: 1.2;
  letter-spacing: .1em;
  text-transform: uppercase;
  white-space: nowrap;
  transition: background var(--dur) ease, color var(--dur) ease, border-color var(--dur) ease;
}
.btn-primary {
  background: var(--signal);
  border-color: var(--signal);
  color: #14100C;
  font-weight: 700;
}
.btn-primary:hover,
.btn-primary:focus-visible {
  background: var(--paper);
  border-color: var(--paper);
  color: var(--ink-900);
}
.btn-ghost {
  background: transparent;
  border-color: var(--grid);
  color: var(--paper);
}
.btn-ghost:hover,
.btn-ghost:focus-visible {
  border-color: var(--terminal);
  color: var(--terminal);
}

/* 标签 */
.tag {
  display: inline-flex;
  align-items: center;
  gap: .3rem;
  padding: .16rem .45rem;
  border: var(--line);
  font-family: var(--font-mono);
  font-size: 10px;
  font-weight: 400;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--slate);
}
.tag-signal { border-color: rgba(255, 107, 53, .55); color: var(--signal); }
.tag-terminal { border-color: rgba(61, 220, 151, .55); color: var(--terminal); }
.tag-paper {
  background: var(--paper-2);
  border-color: var(--paper-2);
  color: var(--ink-900);
}

/* 面板 */
.panel {
  position: relative;
  background: var(--ink-800);
  border: var(--line);
  transition: border-color var(--dur) ease;
}
.panel--interactive:hover,
.panel--interactive:focus-within { border-color: rgba(61, 220, 151, .6); }
.panel-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: .7rem 1rem;
  border-bottom: var(--line);
  background: rgba(47, 74, 94, .2);
}
.panel-index {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .12em;
  color: var(--terminal);
}
.panel-title {
  font-family: var(--font-display);
  font-size: 1.1rem;
  font-weight: 700;
  letter-spacing: .02em;
  color: var(--paper-hi);
}
.panel-tags { display: flex; flex-wrap: wrap; gap: .35rem; }
.panel-body { padding: 1.1rem 1rem; }

/* 面包屑 */
.breadcrumb { font-family: var(--font-mono); font-size: 11px; letter-spacing: .08em; text-transform: uppercase; }
.breadcrumb-list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: .4rem;
  color: var(--slate);
}
.breadcrumb-item { display: inline-flex; align-items: center; gap: .4rem; }
.breadcrumb-link {
  color: var(--slate);
  transition: color var(--dur) ease;
}
.breadcrumb-link:hover,
.breadcrumb-link:focus-visible { color: var(--signal); }
.breadcrumb-sep { color: var(--grid); }
.breadcrumb-current { color: var(--paper); }

/* 栅格 */
.grid { display: grid; gap: var(--gap, 1.25rem); }
.grid--2, .grid--3, .grid--4 { grid-template-columns: minmax(0, 1fr); }

/* 图片取景框（页面阶段放置 <img>） */
.media-frame {
  position: relative;
  overflow: hidden;
  aspect-ratio: 16 / 10;
  background: var(--ink-800);
  border: var(--line);
}
.media-frame img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  filter: saturate(.85) contrast(1.04);
}
.media-frame::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image: repeating-linear-gradient(
    to bottom,
    rgba(47, 74, 94, .32) 0,
    rgba(47, 74, 94, .32) 1px,
    transparent 1px,
    transparent 5px
  );
  opacity: .5;
}
.media-frame--wide { aspect-ratio: 21 / 9; }
.media-frame--tall { aspect-ratio: 3 / 4; }
.media-caption {
  display: flex;
  align-items: baseline;
  gap: .5rem;
  margin-top: .5rem;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .06em;
  color: var(--slate);
}

/* 断点 ------------------------------------------------------------------- */
@media (min-width: 720px) {
  .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(2, minmax(0, 1fr)); }
}

@media (min-width: 1024px) {
  .grid--4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }
}

@media (max-width: 1100px) {
  .nav-link { padding: .5rem .5rem; font-size: .9rem; }
  .nav-link::after { left: .5rem; right: .5rem; }
}

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

@media (max-width: 960px) {
  .nav-toggle { display: inline-flex; }
  .header-actions { margin-left: auto; }
  .site-nav {
    position: absolute;
    left: 0;
    right: 0;
    top: calc(100% + 1px);
    margin-left: 0;
    background: var(--ink-800);
    border-bottom: var(--line);
    max-height: 0;
    overflow: hidden;
    visibility: hidden;
    transition: max-height .28s ease, visibility .28s ease;
  }
  .site-nav[data-open] {
    max-height: 78vh;
    overflow-y: auto;
    visibility: visible;
  }
  .nav-list { flex-direction: column; }
  .nav-item { border-bottom: 1px solid rgba(47, 74, 94, .6); }
  .nav-item:last-child { border-bottom: 0; }
  .nav-link {
    padding: .85rem var(--pad);
    font-size: 1rem;
    justify-content: flex-start;
  }
  .nav-link::after {
    left: var(--pad);
    right: auto;
    width: 28px;
    bottom: .55rem;
  }
  .nav-link[aria-current="page"] { background: rgba(61, 220, 151, .1); }
  .nav-index { font-size: 11px; }
}

@media (max-width: 560px) {
  body { font-size: 16px; }
  .rail-status { display: none; }
  .rail-inner { padding: .35rem var(--pad); }
  .command-inner { gap: .6rem; padding: .6rem var(--pad); }
  .brand-mark { width: 36px; height: 36px; font-size: 1.1rem; }
  .brand-name { font-size: 1rem; }
  .brand-sub { display: none; }
  .btn { padding: .5rem .7rem; font-size: 10px; letter-spacing: .08em; }
  .nav-toggle { padding: .45rem .5rem; font-size: 10px; }
  .footer-grid { grid-template-columns: minmax(0, 1fr); gap: 1.8rem; }
  .contact-inner { grid-template-columns: minmax(0, 1fr); gap: .9rem 1rem; }
  .legal-inner { flex-direction: column; align-items: flex-start; }
}

/* 可访问性：动效降级 ------------------------------------------------------ */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *,
  *::before,
  *::after {
    animation-duration: .001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .001ms !important;
    scroll-behavior: auto !important;
  }
  .nav-link::after { transition: none; }
  .site-nav { transition: none; }
}