/* ==========================================================================
   卡卡湾电投指南 · /assets/site.css
   共享外壳：重置 / 变量 / 中文排版 / 头部 / 页脚 / 通用组件
   ========================================================================== */

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

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

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

ul[class],
ol[class] {
  list-style: none;
  padding: 0;
}

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

button, input, select, textarea {
  font: inherit;
  color: inherit;
}

a { color: inherit; }

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

/* ---------- 2. Tokens ---------- */
:root {
  /* 色彩体系 */
  --abyss: #061726;
  --deep: #0B2C46;
  --hull: #14405F;
  --cyan: #2FE3D2;
  --coral: #FF6B4A;
  --amber: #FFC24B;
  --mist: #C7D3DC;
  --paper: #F6F4EF;
  --line: #DDE3E6;
  --graphite: #1B2A36;

  --rule-dark: rgba(199, 211, 220, 0.16);
  --rule-dark-soft: rgba(199, 211, 220, 0.08);
  --mist-70: rgba(199, 211, 220, 0.7);

  /* 骨架尺寸 */
  --rail: 96px;
  --status-h: 40px;
  --bar-h: 66px;
  --max: 1200px;
  --gutter: clamp(16px, 3vw, 40px);

  /* 字体栈 */
  --sans: "Noto Sans SC", "Source Han Sans SC", "Alibaba PuHuiTi",
          "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei",
          system-ui, -apple-system, sans-serif;
  --display: "Helvetica Neue", "Arial Narrow", "Noto Sans SC",
             "Alibaba PuHuiTi", "PingFang SC", "Microsoft YaHei", sans-serif;
  --mono: "JetBrains Mono", "IBM Plex Mono", ui-monospace, SFMono-Regular,
          Menlo, Consolas, "Courier New", monospace;
}

/* ---------- 3. 中文排版基线 ---------- */
body {
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.85;
  letter-spacing: 0.01em;
  color: var(--paper);
  background-color: var(--abyss);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  min-height: 100vh;
}

@media (min-width: 768px) {
  body { font-size: 17px; }
}

h1, h2, h3, h4 {
  font-family: var(--sans);
  font-weight: 700;
  line-height: 1.25;
  letter-spacing: -0.005em;
}

p { max-width: 38em; }

.mono {
  font-family: var(--mono);
  font-variant-numeric: tabular-nums;
  letter-spacing: 0.08em;
}

/* ---------- 4. 布局工具 ---------- */
.wrap {
  width: 100%;
  max-width: var(--max);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.section { padding-block: clamp(56px, 9vw, 120px); }
.section--tight { padding-block: clamp(32px, 5vw, 64px); }

.grid { display: grid; gap: clamp(20px, 3vw, 40px); }
.grid--7-5 { grid-template-columns: 7fr 5fr; }
.grid--5-7 { grid-template-columns: 5fr 7fr; }

@media (max-width: 860px) {
  .grid--7-5,
  .grid--5-7 { grid-template-columns: 1fr; }
}

.u-rule {
  border: 0;
  border-top: 1px solid var(--rule-dark);
  margin: 0;
}

.prose { max-width: 36em; }
.prose p + p { margin-top: 1.1em; }
.prose h3 { margin-top: 2em; margin-bottom: 0.6em; }

/* ---------- 5. 可访问性 ---------- */
.skip-link {
  position: fixed;
  top: 10px;
  left: 10px;
  z-index: 300;
  padding: 10px 18px;
  background: var(--cyan);
  color: var(--abyss);
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  text-decoration: none;
  transform: translateY(-180%);
  transition: transform 160ms ease;
}

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

@media (min-width: 1024px) {
  .skip-link { left: calc(var(--rail) + 12px); }
}

:where(a, button, [tabindex], summary):focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 3px;
}

/* ---------- 6. 品牌轨道（桌面常驻） ---------- */
.brand-rail { display: none; }

@media (min-width: 1024px) {
  body { padding-left: var(--rail); }

  .brand-rail {
    display: flex;
    position: fixed;
    inset: 0 auto 0 0;
    width: var(--rail);
    z-index: 90;
    flex-direction: column;
    align-items: center;
    justify-content: space-between;
    padding: 18px 0 22px;
    background: var(--abyss);
    border-right: 1px solid var(--rule-dark);
  }
}

.brand-rail__mark {
  display: grid;
  place-items: center;
  width: 34px;
  height: 34px;
  border: 1px solid var(--cyan);
  color: var(--cyan);
  font-family: var(--mono);
  font-size: 14px;
  font-weight: 700;
  letter-spacing: 0;
}

.brand-rail__text {
  writing-mode: vertical-rl;
  text-orientation: mixed;
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.32em;
  color: var(--paper);
}

.brand-rail__meta {
  writing-mode: vertical-rl;
  text-orientation: mixed;
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: 0.24em;
  color: var(--mist-70);
}

/* ---------- 7. 站点头部 ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 80;
  background: transparent;
}

/* 状态栏 */
.status-bar {
  background: var(--abyss);
  border-bottom: 1px solid var(--rule-dark);
}

.status-bar__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  height: var(--status-h);
  max-width: calc(var(--max) + 2 * var(--gutter));
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.status-bar__section,
.status-bar__meta {
  display: flex;
  align-items: center;
  gap: 8px;
  margin: 0;
  font-family: var(--mono);
  font-size: 10.5px;
  letter-spacing: 0.12em;
  color: var(--mist);
  white-space: nowrap;
}

.status-bar__idx {
  color: var(--cyan);
  font-weight: 700;
}

.status-bar__sep { color: rgba(199, 211, 220, 0.4); }

.status-bar__light {
  display: inline-block;
  width: 6px;
  height: 6px;
  flex: 0 0 auto;
  background: var(--amber);
  box-shadow: 0 0 0 3px rgba(255, 194, 75, 0.14);
}

.status-bar__meta span:last-child {
  overflow: hidden;
  text-overflow: ellipsis;
}

/* 顶栏主体 */
.header-bar {
  position: relative;
  background: rgba(6, 23, 38, 0.42);
  -webkit-backdrop-filter: blur(10px);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid transparent;
  transition: background-color 160ms linear, border-color 160ms linear;
}

.site-header[data-scrolled] .header-bar {
  background: var(--abyss);
  -webkit-backdrop-filter: none;
  backdrop-filter: none;
  border-bottom-color: var(--rule-dark);
}

.header-bar__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: clamp(12px, 2vw, 28px);
  height: var(--bar-h);
  max-width: calc(var(--max) + 2 * var(--gutter));
  margin-inline: auto;
  padding-inline: var(--gutter);
}

/* 品牌 */
.brand {
  display: inline-flex;
  align-items: center;
  gap: 11px;
  text-decoration: none;
  color: var(--paper);
  flex: 0 0 auto;
}

.brand__mark {
  display: grid;
  place-items: center;
  width: 34px;
  height: 34px;
  border: 1px solid var(--cyan);
  color: var(--cyan);
  font-size: 15px;
  font-weight: 800;
  letter-spacing: 0;
  line-height: 1;
}

.brand__text { display: block; }

.brand__name {
  display: block;
  font-size: 15px;
  font-weight: 700;
  line-height: 1.25;
  letter-spacing: 0.02em;
}

.brand__tag {
  display: block;
  font-family: var(--mono);
  font-size: 9.5px;
  letter-spacing: 0.2em;
  line-height: 1.5;
  color: var(--mist-70);
}

/* 移动按钮 */
.nav-toggle {
  display: none;
  align-items: center;
  gap: 10px;
  padding: 8px 12px;
  background: transparent;
  border: 1px solid rgba(199, 211, 220, 0.32);
  color: var(--paper);
  cursor: pointer;
  transition: border-color 180ms ease, background-color 180ms ease;
}

.nav-toggle:hover { border-color: var(--cyan); }

.nav-toggle__box {
  display: grid;
  gap: 4px;
  width: 18px;
}

.nav-toggle__box i {
  display: block;
  height: 2px;
  width: 100%;
  background: var(--cyan);
  transition: transform 220ms ease, opacity 180ms ease;
}

.nav-toggle[aria-expanded="true"] .nav-toggle__box i:nth-child(1) {
  transform: translateY(6px) rotate(45deg);
}
.nav-toggle[aria-expanded="true"] .nav-toggle__box i:nth-child(2) {
  opacity: 0;
}
.nav-toggle[aria-expanded="true"] .nav-toggle__box i:nth-child(3) {
  transform: translateY(-6px) rotate(-45deg);
}

.nav-toggle__text {
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: 0.16em;
  color: var(--mist);
}

/* 导航 */
.site-nav {
  display: flex;
  align-items: center;
  gap: clamp(6px, 1vw, 14px);
  min-width: 0;
}

.site-nav__list {
  display: flex;
  align-items: center;
  gap: clamp(4px, 1vw, 16px);
  margin: 0;
}

.site-nav__link {
  position: relative;
  display: inline-flex;
  align-items: baseline;
  gap: 6px;
  padding: 6px 2px;
  font-size: 14px;
  font-weight: 500;
  color: var(--mist);
  text-decoration: none;
  white-space: nowrap;
  transition: color 180ms ease;
}

.site-nav__link::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: -1px;
  height: 2px;
  background: var(--coral);
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform 180ms ease;
}

.site-nav__link:hover { color: var(--paper); }

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

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

.site-nav__num {
  font-family: var(--mono);
  font-size: 9.5px;
  letter-spacing: 0.06em;
  color: rgba(199, 211, 220, 0.5);
  transition: color 180ms ease;
}

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

.site-nav__cta {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  margin-left: clamp(4px, 1vw, 14px);
  padding: 9px 15px;
  background: var(--coral);
  color: var(--abyss);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.02em;
  text-decoration: none;
  white-space: nowrap;
  transition: background-color 180ms ease;
}

.site-nav__cta:hover { background: #ff8469; }

/* 滚动进度线 */
.scroll-meter {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 2px;
  pointer-events: none;
  background: transparent;
}

.scroll-meter__fill {
  display: block;
  height: 100%;
  width: 0;
  background: var(--cyan);
}

/* ---------- 8. 移动 / 平板导航 ---------- */
@media (max-width: 1023px) {
  .nav-toggle { display: inline-flex; }

  .site-nav {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    display: block;
    max-height: 0;
    overflow: hidden;
    padding-inline: var(--gutter);
    background: var(--abyss);
    border-top: 1px solid var(--rule-dark);
    border-bottom: 1px solid var(--rule-dark);
    transition: max-height 220ms ease;
  }

  .site-nav[data-open="true"] {
    max-height: min(72vh, 540px);
    overflow-y: auto;
  }

  .site-nav__list {
    display: block;
    padding: 6px 0;
  }

  .site-nav__item + .site-nav__item {
    border-top: 1px solid var(--rule-dark-soft);
  }

  .site-nav__link {
    display: flex;
    align-items: baseline;
    gap: 14px;
    padding: 15px 2px;
    font-size: 16px;
  }

  .site-nav__link::after {
    top: 50%;
    bottom: auto;
    left: auto;
    right: 2px;
    width: 22px;
    height: 1px;
    transform: scaleX(0);
  }

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

  .site-nav__num {
    min-width: 22px;
    font-size: 11px;
  }

  .site-nav__cta {
    display: flex;
    margin: 8px 0 18px;
    padding: 13px 18px;
    font-size: 14px;
  }
}

@media (max-width: 560px) {
  .brand__tag { letter-spacing: 0.14em; }
  .status-bar__meta span:last-child { font-size: 9.5px; }
}

/* ---------- 9. 页脚 ---------- */
.site-footer {
  position: relative;
  margin-top: clamp(48px, 8vw, 96px);
  padding: clamp(44px, 6vw, 88px) var(--gutter) 0;
  background: var(--abyss);
  border-top: 1px solid var(--rule-dark);
  color: var(--mist);
  overflow: hidden;
}

.site-footer::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image: linear-gradient(to right, rgba(199, 211, 220, 0.055) 1px, transparent 1px);
  background-size: 25% 100%;
  pointer-events: none;
}

.footer-grid {
  position: relative;
  display: grid;
  grid-template-columns: 1fr 0.85fr 1.2fr;
  gap: clamp(28px, 4vw, 64px);
  max-width: var(--max);
  margin-inline: auto;
}

@media (max-width: 980px) {
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .footer-col--contact { grid-column: 1 / -1; }
}

@media (max-width: 640px) {
  .footer-grid { grid-template-columns: 1fr; }
  .footer-col--contact { grid-column: auto; }
}

.footer-col { min-width: 0; }

.footer-brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  color: var(--paper);
  margin-bottom: 12px;
}

.footer-brand__mark {
  display: grid;
  place-items: center;
  width: 30px;
  height: 30px;
  border: 1px solid var(--cyan);
  color: var(--cyan);
  font-size: 13px;
  font-weight: 800;
  letter-spacing: 0;
  line-height: 1;
}

.footer-brand__name {
  font-size: 15px;
  font-weight: 700;
  letter-spacing: 0.03em;
}

.footer-brand__note {
  margin: 0 0 20px;
  max-width: 32em;
  font-size: 12.5px;
  line-height: 1.9;
  color: var(--mist-70);
}

.footer-title {
  margin: 0 0 14px;
  font-family: var(--mono);
  font-size: 10.5px;
  font-weight: 500;
  letter-spacing: 0.18em;
  color: var(--cyan);
}

.footer-links {
  display: grid;
  gap: 0;
  margin: 0;
}

.footer-links__link {
  display: block;
  padding: 8px 0;
  font-size: 14px;
  color: var(--mist);
  text-decoration: none;
  border-bottom: 1px solid var(--rule-dark-soft);
  transition: color 160ms ease, padding-left 160ms ease;
}

.footer-links__link:hover {
  color: var(--paper);
  padding-left: 6px;
}

.footer-steps {
  display: grid;
  gap: 2px;
  margin: 0 0 18px;
}

.footer-steps__item {
  display: flex;
  align-items: baseline;
  gap: 14px;
  padding: 11px 0;
  border-bottom: 1px solid var(--rule-dark-soft);
}

.footer-steps__num {
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--cyan);
  flex: 0 0 auto;
}

.footer-steps__item a {
  font-size: 14px;
  color: var(--mist);
  text-decoration: none;
  transition: color 160ms ease;
}

.footer-steps__item a:hover { color: var(--paper); }

.footer-contact {
  display: grid;
  gap: 14px;
  margin: 0 0 18px;
}

.footer-contact__item {
  display: grid;
  grid-template-columns: 46px minmax(0, 1fr) auto;
  align-items: baseline;
  gap: 10px;
}

.footer-contact__item--wide {
  grid-template-columns: 46px minmax(0, 1fr);
}

.footer-contact__label {
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: 0.14em;
  color: var(--mist-70);
}

.footer-contact__value {
  font-size: 13.5px;
  line-height: 1.7;
  color: var(--paper);
  word-break: break-word;
}

.copy-btn {
  padding: 3px 8px;
  background: transparent;
  border: 1px solid rgba(47, 227, 210, 0.45);
  color: var(--cyan);
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: 0.12em;
  cursor: pointer;
  transition: background-color 160ms ease, color 160ms ease, border-color 160ms ease;
}

.copy-btn:hover {
  background: var(--cyan);
  color: var(--abyss);
}

.copy-btn[data-copied="true"] {
  background: var(--amber);
  border-color: var(--amber);
  color: var(--abyss);
}

.footer-bottom {
  position: relative;
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  justify-content: space-between;
  gap: 14px 28px;
  max-width: var(--max);
  margin: clamp(36px, 5vw, 64px) auto 0;
  padding: 20px 0 32px;
  border-top: 1px solid var(--rule-dark);
}

.footer-legal {
  margin: 0;
  max-width: none;
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--mist-70);
}

.footer-bottom__links {
  display: flex;
  flex-wrap: wrap;
  gap: 6px 20px;
  margin: 0;
}

.footer-bottom__links a {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--mist);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color 160ms ease, border-color 160ms ease;
}

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

/* ---------- 10. 通用组件 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 13px 22px;
  border: 1px solid transparent;
  font-size: 14px;
  font-weight: 700;
  letter-spacing: 0.02em;
  text-decoration: none;
  cursor: pointer;
  transition: background-color 180ms ease, color 180ms ease, border-color 180ms ease;
}

.btn--primary {
  background: var(--coral);
  color: var(--abyss);
}

.btn--primary:hover { background: #ff8469; }

.btn--ghost {
  background: transparent;
  border-color: rgba(199, 211, 220, 0.4);
  color: var(--paper);
}

.btn--ghost:hover {
  border-color: var(--cyan);
  color: var(--cyan);
}

.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 9px;
  border: 1px solid rgba(199, 211, 220, 0.3);
  font-family: var(--mono);
  font-size: 10.5px;
  letter-spacing: 0.1em;
  color: var(--mist);
}

.tag--cyan {
  color: var(--cyan);
  border-color: rgba(47, 227, 210, 0.45);
}

.tag--amber {
  color: var(--amber);
  border-color: rgba(255, 194, 75, 0.45);
}

.crumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-family: var(--mono);
  font-size: 10.5px;
  letter-spacing: 0.1em;
  color: var(--mist-70);
}

.crumbs a {
  color: var(--mist);
  text-decoration: none;
  transition: color 160ms ease;
}

.crumbs a:hover { color: var(--cyan); }

.crumbs__sep {
  color: rgba(199, 211, 220, 0.4);
}

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

.section-head {
  display: flex;
  align-items: baseline;
  gap: 16px;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--rule-dark);
  margin-bottom: clamp(24px, 4vw, 48px);
}

.sec-num {
  font-family: var(--display);
  font-weight: 800;
  font-size: clamp(28px, 4vw, 44px);
  line-height: 1;
  letter-spacing: -0.02em;
  color: transparent;
  -webkit-text-stroke: 1px var(--cyan);
  text-stroke: 1px var(--cyan);
  flex: 0 0 auto;
}

/* 图片槽位基础规则 */
.media {
  position: relative;
  overflow: hidden;
  width: 100%;
  background: var(--hull);
  border: 1px solid var(--rule-dark);
}

.media > img,
.media > picture > img,
.media > svg {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

.media--wide { aspect-ratio: 16 / 9; }
.media--tall { aspect-ratio: 3 / 4; }
.media--square { aspect-ratio: 1 / 1; }

.media--slant {
  clip-path: polygon(0 0, 100% 0, 100% 90%, 0 100%);
}

.media__caption {
  display: block;
  padding: 10px 0 0;
  font-family: var(--mono);
  font-size: 10.5px;
  letter-spacing: 0.1em;
  color: var(--mist-70);
}

/* ---------- 11. 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;
    scroll-behavior: auto !important;
  }
}