:root {
  --deep-ink: #0A1F44;
  --reduced-ink: #14294D;
  --paper: #F5F2EC;
  --paper-deep: #EBE6DD;
  --accent: #FF6B35;
  --accent-light: #FFB28A;
  --neutral-mist: #D8DCE3;
  --muted-text: #5A6A80;
  --white: #FFFFFF;
  --black-smoke: #111827;
  --font-heading: 'Anton', 'Noto Sans SC', 'PingFang SC', sans-serif;
  --font-body: 'Inter', 'Noto Sans SC', 'Helvetica Neue', sans-serif;
  --font-label: 'Noto Sans SC', 'Inter', monospace;
  --shell-max: 1440px;
  --header-h: 72px;
  --gap: 24px;
}

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

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

body {
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 26px;
  color: var(--deep-ink);
  background-color: var(--paper);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

ul,
ol {
  list-style: none;
}

address {
  font-style: normal;
}

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

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

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

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

:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
}

#main-content {
  flex: 1 0 auto;
  width: 100%;
}

h1,
h2,
h3,
h4 {
  font-family: var(--font-heading);
  color: var(--deep-ink);
}

h1 {
  font-size: 40px;
  line-height: 48px;
  letter-spacing: 1px;
}

h2 {
  font-size: 28px;
  line-height: 36px;
}

h3 {
  font-size: 20px;
  line-height: 28px;
}

/* ====================== 可访问性 ====================== */
.skip-link {
  position: fixed;
  top: -100px;
  left: 16px;
  z-index: 1000;
  display: inline-block;
  background: var(--accent);
  color: var(--deep-ink);
  font-family: var(--font-label);
  font-size: 14px;
  font-weight: 700;
  padding: 12px 20px;
  border-radius: 2px;
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.2);
  transition: top 0.2s ease;
}

.skip-link:focus,
.skip-link:focus-visible {
  top: 16px;
}

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  clip-path: inset(50%);
  white-space: nowrap;
}

/* ====================== 阅读进度 ====================== */
.reading-progress {
  position: fixed;
  top: 0;
  left: 0;
  width: 0;
  height: 3px;
  background: var(--accent);
  z-index: 500;
  pointer-events: none;
}

/* ====================== 头部命令栏 ====================== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 200;
  background: var(--deep-ink);
  color: var(--white);
  flex-shrink: 0;
}

.site-header::after {
  content: '';
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 2px;
  background: var(--accent);
}

.header-shell {
  max-width: var(--shell-max);
  margin: 0 auto;
  min-height: var(--header-h);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 0 24px;
}

.brand-lockup {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  flex-shrink: 0;
}

.brand-lockup-mark {
  width: 38px;
  height: 38px;
  display: grid;
  place-items: center;
  background: var(--accent);
  color: var(--deep-ink);
  font-family: var(--font-label);
  font-size: 19px;
  font-weight: 700;
  line-height: 1;
  border-radius: 2px;
}

.brand-lockup-name {
  display: block;
  font-family: var(--font-heading);
  font-size: 18px;
  line-height: 1;
  letter-spacing: 2px;
  color: var(--white);
}

.brand-lockup-sub {
  display: block;
  margin-top: 4px;
  font-family: var(--font-label);
  font-size: 10px;
  letter-spacing: 2px;
  text-transform: uppercase;
  color: var(--neutral-mist);
}

.header-nav {
  display: flex;
  align-items: center;
  flex: 1;
  justify-content: flex-end;
}

.nav-rail {
  display: flex;
  align-items: stretch;
  gap: 2px;
}

.nav-rail-item {
  display: flex;
}

.nav-rail-link {
  position: relative;
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 22px 12px;
  font-family: var(--font-body);
  font-size: 14px;
  font-weight: 500;
  line-height: 1;
  color: rgba(255, 255, 255, 0.82);
  transition: color 0.2s ease, background-color 0.2s ease;
}

.nav-rail-link:hover {
  color: var(--accent-light);
}

.nav-rail-link[aria-current="page"] {
  color: var(--accent);
}

.nav-rail-link[aria-current="page"]::after {
  content: '';
  position: absolute;
  left: 12px;
  right: 12px;
  bottom: -2px;
  height: 3px;
  background: var(--accent);
}

.nav-rail-index {
  font-family: var(--font-label);
  font-size: 10px;
  letter-spacing: 1px;
  color: var(--accent);
}

.header-aside {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-shrink: 0;
}

.header-login {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  min-height: 40px;
  padding: 0 16px;
  background: var(--accent);
  color: var(--deep-ink);
  font-family: var(--font-label);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.5px;
  white-space: nowrap;
  border-radius: 2px;
  transition: background-color 0.2s ease, color 0.2s ease;
}

.header-login:hover {
  background: var(--accent-light);
  color: var(--deep-ink);
}

.header-login-dot {
  width: 8px;
  height: 8px;
  flex-shrink: 0;
  border-radius: 50%;
  background: var(--deep-ink);
  animation: dot-pulse 2.4s ease-out infinite;
}

@keyframes dot-pulse {
  0%, 100% {
    box-shadow: 0 0 0 0 rgba(10, 31, 68, 0.35);
  }
  50% {
    box-shadow: 0 0 0 6px rgba(10, 31, 68, 0);
  }
}

.header-login-long {
  display: inline;
}

.header-login-short {
  display: none;
}

.nav-toggle {
  display: none;
  width: 44px;
  height: 44px;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 5px;
  border: 1px solid rgba(255, 255, 255, 0.22);
  border-radius: 2px;
  transition: border-color 0.2s ease;
}

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

.nav-toggle-bar {
  display: block;
  width: 20px;
  height: 2px;
  background: var(--white);
  transition: transform 0.25s ease, opacity 0.25s ease;
}

.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(1) {
  transform: translateY(7px) 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(-7px) rotate(-45deg);
}

/* ====================== 页脚 ====================== */
.site-footer {
  position: relative;
  background: var(--deep-ink);
  color: var(--white);
  flex-shrink: 0;
  margin-top: auto;
}

.site-footer::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 3px;
  background: repeating-linear-gradient(90deg, var(--accent) 0 56px, transparent 56px 112px);
}

.footer-shell {
  position: relative;
  max-width: var(--shell-max);
  margin: 0 auto;
  padding: 48px 24px 20px;
}

.footer-vertical-rail {
  writing-mode: vertical-rl;
  position: absolute;
  right: 24px;
  top: 60px;
  bottom: 60px;
  font-family: var(--font-label);
  font-size: 10px;
  letter-spacing: 6px;
  color: rgba(255, 255, 255, 0.18);
  text-transform: uppercase;
  pointer-events: none;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 0.8fr 0.8fr 1.2fr;
  gap: 28px 32px;
}

.footer-card {
  padding-top: 4px;
}

.footer-brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
}

.footer-brand-mark {
  width: 38px;
  height: 38px;
  display: grid;
  place-items: center;
  border: 2px solid var(--accent);
  color: var(--accent);
  font-family: var(--font-label);
  font-size: 18px;
  font-weight: 700;
  border-radius: 2px;
}

.footer-brand-name {
  display: block;
  font-family: var(--font-heading);
  font-size: 18px;
  line-height: 1.1;
  letter-spacing: 2px;
  color: var(--white);
}

.footer-brand-sub {
  display: block;
  margin-top: 3px;
  font-family: var(--font-label);
  font-size: 10px;
  letter-spacing: 2px;
  text-transform: uppercase;
  color: rgba(255, 255, 255, 0.5);
}

.footer-trust {
  margin-top: 20px;
  max-width: 48ch;
  font-size: 12px;
  line-height: 20px;
  color: rgba(255, 255, 255, 0.55);
  border-left: 2px solid var(--accent);
  padding-left: 12px;
}

.footer-heading {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 12px;
  font-family: var(--font-label);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 2px;
  text-transform: uppercase;
  color: var(--accent);
}

.footer-heading::after {
  content: '';
  height: 1px;
  flex: 1;
  background: rgba(255, 255, 255, 0.15);
}

.footer-list {
  display: grid;
  gap: 2px;
}

.footer-list a {
  display: inline-block;
  padding: 4px 0;
  font-size: 14px;
  color: rgba(255, 255, 255, 0.72);
  transition: color 0.2s ease, padding-left 0.2s ease;
}

.footer-list a:hover {
  color: var(--accent-light);
  padding-left: 4px;
}

.footer-address {
  display: grid;
  gap: 2px;
}

.footer-address-row {
  display: block;
  font-size: 13px;
  line-height: 22px;
  color: rgba(255, 255, 255, 0.72);
}

.footer-service {
  margin-top: 12px;
  font-size: 12px;
  line-height: 18px;
  color: rgba(255, 255, 255, 0.45);
}

.footer-meta {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 8px 16px;
  margin-top: 40px;
  padding-top: 16px;
  border-top: 1px solid rgba(255, 255, 255, 0.12);
  font-family: var(--font-label);
  font-size: 12px;
  color: rgba(255, 255, 255, 0.5);
}

/* ====================== 通用组件 ====================== */
.shell {
  max-width: var(--shell-max);
  margin: 0 auto;
  padding-left: 24px;
  padding-right: 24px;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  min-height: 44px;
  padding: 0 22px;
  font-family: var(--font-label);
  font-size: 14px;
  font-weight: 600;
  line-height: 1;
  border-radius: 2px;
  border: 1px solid transparent;
  cursor: pointer;
  white-space: nowrap;
  transition: background-color 0.2s ease, border-color 0.2s ease, color 0.2s ease;
}

.button-primary {
  background: var(--accent);
  color: var(--deep-ink);
  border-color: var(--accent);
}

.button-primary:hover {
  background: var(--accent-light);
  border-color: var(--accent-light);
}

.button-outline {
  background: transparent;
  color: var(--deep-ink);
  border-color: var(--deep-ink);
}

.button-outline:hover {
  background: var(--deep-ink);
  color: var(--paper);
}

.button-ghost {
  background: transparent;
  color: var(--paper);
  border-color: rgba(255, 255, 255, 0.35);
}

.button-ghost:hover {
  background: var(--paper);
  color: var(--deep-ink);
  border-color: var(--paper);
}

.card {
  position: relative;
  background: var(--white);
  border: 1px solid var(--neutral-mist);
  padding: 20px;
}

.card-stack {
  box-shadow: 8px 8px 0 var(--paper-deep);
}

.card-ink {
  background: var(--deep-ink);
  border-color: var(--deep-ink);
  color: var(--white);
}

.panel {
  position: relative;
  background: var(--white);
  border: 1px solid var(--deep-ink);
  padding: 24px;
}

.panel-stack {
  box-shadow: 10px 10px 0 var(--deep-ink);
}

.display-title {
  font-family: var(--font-heading);
  font-size: clamp(40px, 6vw, 72px);
  line-height: 0.95;
  letter-spacing: 1px;
  color: var(--deep-ink);
}

.index-label {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-label);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 2px;
  text-transform: uppercase;
  color: var(--accent);
}

.index-label::before {
  content: '';
  width: 20px;
  height: 2px;
  background: var(--accent);
  flex-shrink: 0;
}

.vertical-label {
  writing-mode: vertical-rl;
  font-family: var(--font-label);
  font-size: 11px;
  letter-spacing: 3px;
  text-transform: uppercase;
  color: var(--muted-text);
}

.coordinate {
  display: inline-block;
  padding: 2px 6px;
  font-family: var(--font-label);
  font-size: 10px;
  letter-spacing: 1px;
  color: var(--muted-text);
  border: 1px solid var(--neutral-mist);
  background: var(--white);
  white-space: nowrap;
}

.legend {
  display: flex;
  flex-wrap: wrap;
  gap: 12px 20px;
  font-family: var(--font-label);
  font-size: 11px;
  color: var(--muted-text);
}

.legend-item {
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

.legend-key {
  width: 12px;
  height: 12px;
  flex-shrink: 0;
  border: 1px solid var(--deep-ink);
  background: transparent;
}

.legend-key-accent {
  background: var(--accent);
  border-color: var(--accent);
}

.legend-key-ink {
  background: var(--deep-ink);
  border-color: var(--deep-ink);
}

.legend-key-mist {
  background: var(--neutral-mist);
  border-color: var(--neutral-mist);
}

.chip {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 12px;
  font-family: var(--font-label);
  font-size: 12px;
  line-height: 18px;
  border: 1px solid var(--neutral-mist);
  border-radius: 999px;
  background: var(--white);
  color: var(--muted-text);
}

.chip-accent {
  background: var(--accent);
  border-color: var(--accent);
  color: var(--deep-ink);
  font-weight: 600;
}

.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 6px 8px;
  font-family: var(--font-label);
  font-size: 12px;
  color: var(--muted-text);
}

.breadcrumb a {
  color: var(--muted-text);
  transition: color 0.2s ease;
}

.breadcrumb a:hover {
  color: var(--accent);
}

.breadcrumb-current {
  color: var(--deep-ink);
  font-weight: 600;
}

.prose {
  max-width: 78ch;
  line-height: 28px;
}

.prose h1,
.prose h2,
.prose h3 {
  margin-top: 32px;
  margin-bottom: 16px;
  line-height: 1.2;
}

.prose p {
  margin-bottom: 16px;
}

.prose a {
  color: var(--accent);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.grid {
  display: grid;
  gap: var(--gap);
}

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

.grid-3 {
  grid-template-columns: repeat(3, 1fr);
}

.grid-4 {
  grid-template-columns: repeat(4, 1fr);
}

/* ====================== 图片容器 ====================== */
.image-container {
  position: relative;
  background: var(--paper-deep);
  border: 1px solid var(--neutral-mist);
  overflow: hidden;
}

.image-container::before {
  content: 'IMG';
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  font-family: var(--font-label);
  font-size: 11px;
  letter-spacing: 2px;
  color: var(--muted-text);
  opacity: 0.5;
  pointer-events: none;
}

.image-container img,
.image-container picture,
.image-container video {
  position: relative;
  z-index: 1;
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

.ratio-16x9 {
  aspect-ratio: 16 / 9;
}

.ratio-4x3 {
  aspect-ratio: 4 / 3;
}

.ratio-3x2 {
  aspect-ratio: 3 / 2;
}

.ratio-1x1 {
  aspect-ratio: 1 / 1;
}

/* ====================== 首屏框景 ====================== */
.hero-frame {
  position: relative;
  border: 1px solid var(--deep-ink);
  background: var(--white);
  padding: clamp(24px, 4vw, 48px);
}

.hero-frame[data-frame-label]::before {
  content: attr(data-frame-label);
  position: absolute;
  top: -11px;
  right: 16px;
  padding: 0 8px;
  background: var(--paper);
  font-family: var(--font-label);
  font-size: 11px;
  letter-spacing: 2px;
  text-transform: uppercase;
  color: var(--muted-text);
}

.hero-frame::after {
  content: '';
  position: absolute;
  top: -1px;
  left: -1px;
  width: 36px;
  height: 4px;
  background: var(--accent);
}

/* ====================== 滚动显现 ====================== */
[data-reveal] {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.5s ease, transform 0.5s ease;
}

[data-reveal].is-revealed {
  opacity: 1;
  transform: translateY(0);
}

[data-reveal][data-reveal-delay="1"] {
  transition-delay: 80ms;
}

[data-reveal][data-reveal-delay="2"] {
  transition-delay: 160ms;
}

[data-reveal][data-reveal-delay="3"] {
  transition-delay: 240ms;
}

[data-reveal][data-reveal-delay="4"] {
  transition-delay: 320ms;
}

[data-reveal][data-reveal-delay="5"] {
  transition-delay: 400ms;
}

[data-reveal][data-reveal-delay="6"] {
  transition-delay: 480ms;
}

[data-reveal][data-reveal-delay="7"] {
  transition-delay: 560ms;
}

/* ====================== 响应式 ====================== */
@media (max-width: 1280px) {
  .header-login-long {
    display: none;
  }

  .header-login-short {
    display: inline;
  }

  .footer-vertical-rail {
    display: none;
  }

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

@media (max-width: 1024px) {
  :root {
    --header-h: 60px;
  }

  .header-nav {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--deep-ink);
    border-bottom: 3px solid var(--accent);
    box-shadow: 0 24px 48px rgba(0, 0, 0, 0.35);
    max-height: calc(100vh - var(--header-h));
    overflow-y: auto;
  }

  .header-nav[data-open="true"] {
    display: block;
  }

  .nav-rail {
    flex-direction: column;
    padding: 8px 0 16px;
  }

  .nav-rail-link {
    padding: 14px 24px;
    border-left: 3px solid transparent;
  }

  .nav-rail-link:hover {
    background: rgba(255, 255, 255, 0.04);
  }

  .nav-rail-link[aria-current="page"] {
    color: var(--accent-light);
    border-left-color: var(--accent);
    background: rgba(255, 255, 255, 0.05);
  }

  .nav-rail-link[aria-current="page"]::after {
    display: none;
  }

  .nav-rail-index {
    width: 24px;
  }

  .nav-toggle {
    display: inline-flex;
    align-items: center;
    justify-content: center;
  }

  .header-aside {
    margin-left: auto;
  }
}

@media (max-width: 640px) {
  .header-shell {
    padding: 0 16px;
    min-height: 56px;
  }

  .brand-lockup-mark {
    width: 30px;
    height: 30px;
    font-size: 15px;
  }

  .brand-lockup-name {
    font-size: 15px;
    letter-spacing: 1px;
  }

  .brand-lockup-sub {
    font-size: 9px;
    letter-spacing: 1px;
  }

  .header-login {
    min-height: 36px;
    padding: 0 10px;
    font-size: 12px;
  }

  .header-login-dot {
    width: 6px;
    height: 6px;
  }

  .footer-shell {
    padding: 36px 16px 16px;
  }

  .footer-grid {
    grid-template-columns: 1fr;
    gap: 28px;
  }

  .footer-meta {
    flex-direction: column;
    align-items: flex-start;
  }

  .grid-2,
  .grid-3,
  .grid-4 {
    grid-template-columns: 1fr;
  }
}

/* ====================== 减少动效 ====================== */
@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    animation-duration: 0.001s !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001s !important;
  }

  .header-login-dot {
    animation: none;
  }

  [data-reveal] {
    opacity: 1;
    transform: none;
    transition: none;
  }
}