:root {
  --color-primary: #FF4D00;
  --color-primary-bright: #FF8A00;
  --color-dark: #0A1B3D;
  --color-silver: #B0B5BD;
  --color-light-blue: #4A6FA5;
  --color-white: #FFFFFF;
  --color-dark-gray: #1A1A1A;
  --color-off-white: #F5F5F5;
  --font-heading: 'Impact', 'Arial Black', 'PingFang SC', 'Microsoft YaHei', sans-serif;
  --font-number: 'Roboto Mono', 'Consolas', 'Courier New', monospace;
  --font-body: 'Noto Sans SC', 'Microsoft YaHei', 'PingFang SC', sans-serif;
  --side-space: 120px;
  --content-pad: 48px;
  --content-max: 1440px;
  --transition-speed: 0.2s;
}

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

html {
  font-size: 16px;
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-body);
  background-color: var(--color-off-white);
  background-image:
    linear-gradient(rgba(10, 27, 61, 0.04) 1px, transparent 1px),
    linear-gradient(90deg, rgba(10, 27, 61, 0.04) 1px, transparent 1px);
  background-size: 32px 32px;
  color: var(--color-dark-gray);
  line-height: 1.75;
  min-height: 100vh;
  overflow-x: hidden;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
}

#main-content {
  margin-left: var(--side-space);
  min-height: 60vh;
}

h1, h2, h3, h4 {
  font-family: var(--font-heading);
  font-weight: 900;
  letter-spacing: -0.02em;
  line-height: 1.2;
  color: var(--color-dark);
}

h1 { font-size: 44px; }
h2 { font-size: 32px; }
h3 { font-size: 22px; }
h4 { font-size: 18px; }

p { margin-bottom: 1em; }

a {
  color: var(--color-light-blue);
  transition: color var(--transition-speed) ease;
}

a:hover { color: var(--color-primary); }

ul, ol { list-style: none; }

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

button {
  font-family: var(--font-body);
  cursor: pointer;
}

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

::selection {
  background: var(--color-primary);
  color: var(--color-white);
}

/* ===== 页面通用组件 ===== */

.page-container {
  max-width: var(--content-max);
  margin: 0 auto;
  padding: 32px var(--content-pad);
}

.content-section {
  padding: 48px 0;
}

.content-section + .content-section {
  border-top: 1px solid rgba(26, 26, 26, 0.08);
}

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

.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  gap: 6px 12px;
  padding: 16px 0;
  font-size: 13px;
  color: var(--color-silver);
}

.breadcrumb a {
  color: var(--color-light-blue);
  text-decoration: none;
}

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

.breadcrumb-item[aria-current="page"] {
  color: var(--color-dark);
  font-weight: 600;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 10px 24px;
  font-family: var(--font-body);
  font-weight: 600;
  font-size: 14px;
  line-height: 1.5;
  border: 1px solid transparent;
  cursor: pointer;
  text-decoration: none;
  color: var(--color-white);
  clip-path: polygon(0 0, calc(100% - 12px) 0, 100% 12px, 100% 100%, 12px 100%, 0 calc(100% - 12px));
  transition: background var(--transition-speed) ease, color var(--transition-speed) ease, border-color var(--transition-speed) ease;
}

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

.btn-primary:hover {
  background: var(--color-primary-bright);
  color: var(--color-white);
}

.btn-outline {
  background: transparent;
  border-color: var(--color-primary);
  color: var(--color-primary);
}

.btn-outline:hover {
  background: var(--color-primary);
  color: var(--color-white);
}

.img-frame {
  position: relative;
  overflow: hidden;
  background: var(--color-dark);
  clip-path: polygon(0 0, calc(100% - 20px) 0, 100% 20px, 100% 100%, 20px 100%, 0 calc(100% - 20px));
}

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

.img-frame::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(10, 27, 61, 0.35) 0%, transparent 60%);
  pointer-events: none;
}

/* ===== Skip Link ===== */

.skip-link {
  position: fixed;
  top: -100px;
  left: 16px;
  z-index: 9999;
  padding: 12px 24px;
  background: var(--color-primary);
  color: var(--color-white);
  font-family: var(--font-body);
  font-weight: 600;
  font-size: 14px;
  text-decoration: none;
  clip-path: polygon(0 0, calc(100% - 12px) 0, 100% 12px, 100% 100%, 12px 100%, 0 calc(100% - 12px));
}

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

/* ===== Site Header ===== */

.site-header {
  position: fixed;
  inset: 0;
  z-index: 2000;
  pointer-events: none;
}

.site-header > * {
  pointer-events: auto;
}

.scroll-track {
  position: absolute;
  top: 0;
  left: 0;
  height: 3px;
  width: 0;
  background: linear-gradient(90deg, var(--color-primary), var(--color-primary-bright));
  z-index: 10;
  box-shadow: 0 0 8px rgba(255, 77, 0, 0.5);
}

.brand {
  position: absolute;
  top: 24px;
  left: 24px;
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 8px 16px;
  background: var(--color-dark);
  text-decoration: none;
  clip-path: polygon(0 0, calc(100% - 12px) 0, 100% 12px, 100% 100%, 12px 100%, 0 calc(100% - 12px));
  transition: background var(--transition-speed) ease;
}

.brand:hover {
  background: #0F2854;
}

.brand-mark {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  background: var(--color-primary);
  color: var(--color-white);
  font-family: var(--font-heading);
  font-size: 22px;
  line-height: 1;
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 8px), calc(100% - 8px) 100%, 0 100%);
}

.brand-word {
  font-family: var(--font-heading);
  font-size: 20px;
  color: var(--color-white);
  letter-spacing: 0.06em;
  line-height: 1.1;
  white-space: nowrap;
}

.brand-cn {
  font-style: normal;
  font-size: 12px;
  color: var(--color-primary);
  vertical-align: super;
  margin-left: 4px;
}

.side-nav {
  position: absolute;
  left: 12px;
  top: 50%;
  transform: translateY(-50%);
  min-width: 96px;
  background: rgba(10, 27, 61, 0.92);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  border: 1px solid rgba(176, 181, 189, 0.25);
  padding: 12px 0;
  clip-path: polygon(0 0, calc(100% - 16px) 0, 100% 16px, 100% calc(100% - 16px), calc(100% - 16px) 100%, 0 100%);
}

.nav-list {
  display: flex;
  flex-direction: column;
}

.nav-item + .nav-item {
  position: relative;
}

.nav-item + .nav-item::before {
  content: "";
  position: absolute;
  top: 0;
  left: 16px;
  right: 16px;
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(176, 181, 189, 0.3), transparent);
}

.nav-link {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 2px;
  padding: 10px 8px;
  text-decoration: none;
  position: relative;
  transition: background var(--transition-speed) ease;
}

.nav-link::after {
  content: "";
  position: absolute;
  left: 0;
  top: 22%;
  bottom: 22%;
  width: 3px;
  background: var(--color-primary);
  opacity: 0;
  transition: opacity var(--transition-speed) ease;
}

.nav-link:hover {
  background: rgba(255, 255, 255, 0.05);
}

.nav-link:hover::after,
.nav-link[aria-current="page"]::after {
  opacity: 1;
}

.nav-index {
  font-family: var(--font-number);
  font-size: 10px;
  color: var(--color-silver);
  letter-spacing: 0.12em;
}

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

.nav-label {
  font-size: 13px;
  color: var(--color-white);
  letter-spacing: 0.08em;
  line-height: 1.4;
}

.nav-link:hover .nav-label,
.nav-link[aria-current="page"] .nav-label {
  color: var(--color-primary-bright);
}

.header-tools {
  position: absolute;
  top: 20px;
  right: 24px;
  display: flex;
  align-items: center;
  gap: 12px;
}

.clock-panel {
  background: var(--color-dark);
  padding: 8px 16px;
  display: flex;
  align-items: baseline;
  gap: 10px;
  clip-path: polygon(0 0, calc(100% - 10px) 0, 100% 10px, 100% 100%, 10px 100%, 0 calc(100% - 10px));
  border: 1px solid rgba(176, 181, 189, 0.3);
}

.clock-time {
  font-family: var(--font-number);
  font-size: 18px;
  font-weight: 700;
  color: var(--color-white);
  font-variant-numeric: tabular-nums;
  line-height: 1;
}

.clock-time.tick {
  animation: clock-tick 0.5s ease;
}

.clock-zone {
  font-size: 10px;
  color: var(--color-silver);
  letter-spacing: 0.08em;
  line-height: 1;
}

.quick-box {
  position: relative;
}

.score-badge {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 8px 14px;
  background: rgba(255, 77, 0, 0.15);
  border: 1px solid rgba(255, 77, 0, 0.4);
  color: var(--color-white);
  font-size: 13px;
  font-family: var(--font-body);
  cursor: pointer;
  clip-path: polygon(8px 0, 100% 0, 100% calc(100% - 8px), calc(100% - 8px) 100%, 0 100%, 0 8px);
  transition: background var(--transition-speed) ease;
}

.score-badge:hover {
  background: rgba(255, 77, 0, 0.3);
}

.score-badge[aria-expanded="true"] {
  background: rgba(255, 77, 0, 0.35);
}

.score-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--color-primary);
  animation: dot-pulse 1.4s ease-in-out infinite;
}

.score-text {
  font-family: var(--font-number);
  letter-spacing: 0.02em;
  white-space: nowrap;
}

.score-arrow {
  font-size: 10px;
  color: var(--color-silver);
  transition: transform var(--transition-speed) ease;
}

.score-badge[aria-expanded="true"] .score-arrow {
  transform: rotate(180deg);
}

.quick-panel {
  position: absolute;
  right: 0;
  top: calc(100% + 8px);
  min-width: 180px;
  background: var(--color-dark);
  border: 1px solid rgba(176, 181, 189, 0.25);
  padding: 14px;
  clip-path: polygon(0 0, calc(100% - 14px) 0, 100% 14px, 100% 100%, 14px 100%, 0 calc(100% - 14px));
  display: none;
  z-index: 20;
  box-shadow: 0 12px 32px rgba(0, 0, 0, 0.35);
}

.quick-panel[data-open] {
  display: block;
  animation: panel-in 0.2s ease;
}

.quick-title {
  font-family: var(--font-number);
  font-size: 10px;
  color: var(--color-silver);
  letter-spacing: 0.14em;
  margin-bottom: 8px;
  padding-bottom: 6px;
  border-bottom: 1px solid rgba(176, 181, 189, 0.15);
}

.quick-link {
  display: block;
  padding: 6px 4px;
  color: var(--color-white);
  text-decoration: none;
  font-size: 13px;
  transition: color var(--transition-speed) ease, padding-left var(--transition-speed) ease;
}

.quick-link:hover {
  color: var(--color-primary-bright);
  padding-left: 8px;
}

.nav-toggle {
  display: none;
  position: absolute;
  top: 16px;
  left: 16px;
  flex-direction: column;
  align-items: center;
  gap: 4px;
  padding: 10px 12px;
  background: var(--color-dark);
  border: 1px solid rgba(176, 181, 189, 0.3);
  color: var(--color-white);
  clip-path: polygon(0 0, calc(100% - 8px) 0, 100% 8px, 100% 100%, 0 100%);
  z-index: 20;
}

.toggle-line {
  display: block;
  width: 18px;
  height: 2px;
  background: var(--color-white);
}

.toggle-label {
  font-size: 10px;
  letter-spacing: 0.08em;
  color: var(--color-silver);
}

/* ===== Site Footer ===== */

.site-footer {
  background: var(--color-dark);
  color: var(--color-white);
  position: relative;
  overflow: hidden;
}

.site-footer::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--color-primary) 0%, var(--color-primary-bright) 60%, transparent 100%);
}

.site-footer::after {
  content: "";
  position: absolute;
  right: -80px;
  bottom: -80px;
  width: 260px;
  height: 260px;
  border: 1px solid rgba(176, 181, 189, 0.15);
  transform: rotate(45deg);
  pointer-events: none;
}

.footer-top {
  max-width: calc(var(--content-max) + var(--side-space));
  margin: 0 auto;
  padding: 56px var(--content-pad) 40px calc(var(--side-space) + var(--content-pad));
  display: grid;
  grid-template-columns: 1.4fr 1fr 1.2fr;
  gap: 48px;
  position: relative;
  z-index: 1;
}

.footer-slogan {
  font-family: var(--font-heading);
  font-size: 32px;
  font-weight: 900;
  line-height: 1.2;
  color: var(--color-white);
  letter-spacing: 0.02em;
  margin-bottom: 20px;
  position: relative;
}

.footer-slogan::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -4px;
  width: 48px;
  height: 3px;
  background: var(--color-primary);
}

.footer-desc {
  color: var(--color-silver);
  font-size: 14px;
  max-width: 420px;
  margin-bottom: 16px;
}

.footer-trust {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 12px;
  background: rgba(74, 111, 165, 0.15);
  border: 1px solid rgba(74, 111, 165, 0.3);
  font-size: 12px;
  color: var(--color-light-blue);
  line-height: 1.6;
}

.footer-title {
  font-size: 14px;
  font-weight: 600;
  color: var(--color-silver);
  letter-spacing: 0.12em;
  margin-bottom: 16px;
  padding-bottom: 8px;
  border-bottom: 1px solid rgba(176, 181, 189, 0.2);
}

.footer-list {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.footer-list li {
  font-size: 14px;
  color: var(--color-silver);
  line-height: 1.6;
  overflow-wrap: break-word;
}

.footer-list a {
  color: var(--color-white);
  text-decoration: none;
  font-size: 14px;
  transition: color var(--transition-speed) ease, padding-left var(--transition-speed) ease;
}

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

.footer-contact-label {
  display: inline-block;
  width: 36px;
  color: var(--color-light-blue);
  font-size: 12px;
  font-family: var(--font-number);
  letter-spacing: 0.04em;
}

.footer-legal {
  margin-top: 20px;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 6px;
  font-size: 12px;
}

.footer-legal a {
  color: var(--color-silver);
  text-decoration: none;
  padding: 4px 8px;
  border: 1px solid rgba(176, 181, 189, 0.2);
  transition: border-color var(--transition-speed) ease, color var(--transition-speed) ease;
}

.footer-legal a:hover {
  border-color: var(--color-primary);
  color: var(--color-primary-bright);
}

.legal-sep {
  color: rgba(176, 181, 189, 0.4);
}

.footer-bottom {
  max-width: calc(var(--content-max) + var(--side-space));
  margin: 0 auto;
  padding: 16px var(--content-pad) 16px calc(var(--side-space) + var(--content-pad));
  border-top: 1px solid rgba(176, 181, 189, 0.15);
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
  flex-wrap: wrap;
  position: relative;
  z-index: 1;
}

.footer-axis,
.footer-icp,
.footer-year {
  color: var(--color-silver);
  font-size: 12px;
  font-family: var(--font-number);
}

.footer-axis {
  letter-spacing: 0.04em;
}

/* ===== Animation Keyframes ===== */

@keyframes dot-pulse {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.45; transform: scale(0.78); }
}

@keyframes clock-tick {
  0% { color: var(--color-white); }
  25% { color: var(--color-primary); }
  100% { color: var(--color-white); }
}

@keyframes panel-in {
  from { opacity: 0; transform: translateY(-6px); }
  to { opacity: 1; transform: translateY(0); }
}

/* ===== Responsive ===== */

@media (max-width: 1199px) {
  .footer-top {
    grid-template-columns: 1fr 1fr;
  }

  .footer-brand-col {
    grid-column: 1 / -1;
  }

  .footer-slogan {
    font-size: 28px;
  }
}

@media (max-width: 1023px) {
  :root {
    --side-space: 0px;
  }

  #main-content {
    margin-left: 0;
  }

  .brand {
    top: 16px;
    left: 64px;
    padding: 6px 12px;
  }

  .brand-mark {
    width: 30px;
    height: 30px;
    font-size: 18px;
  }

  .brand-word {
    font-size: 17px;
  }

  .side-nav {
    position: fixed;
    left: 0;
    top: 0;
    bottom: 0;
    width: 240px;
    min-width: 240px;
    height: 100vh;
    transform: translateX(-100%);
    border-radius: 0;
    border-left: none;
    border-top: none;
    border-bottom: none;
    padding-top: 72px;
    clip-path: none;
    transition: transform 0.28s ease;
    z-index: 10;
    overflow-y: auto;
    background: rgba(10, 27, 61, 0.98);
  }

  .side-nav[data-open] {
    transform: translateX(0);
  }

  .nav-link {
    align-items: flex-start;
    padding: 12px 24px;
    gap: 4px;
  }

  .nav-link::after {
    left: auto;
    right: 12px;
    width: 3px;
    top: 15%;
    bottom: 15%;
  }

  .nav-label {
    font-size: 15px;
  }

  .nav-toggle {
    display: flex;
  }

  .header-tools {
    top: 16px;
    right: 16px;
    gap: 8px;
  }

  .clock-panel {
    padding: 6px 12px;
  }

  .clock-time {
    font-size: 15px;
  }

  .footer-top {
    padding: 48px var(--content-pad) 32px;
    grid-template-columns: 1fr;
  }

  .footer-brand-col {
    grid-column: auto;
  }

  .footer-bottom {
    padding: 16px var(--content-pad);
  }
}

@media (max-width: 767px) {
  .content-section {
    padding: 32px 0;
  }

  .page-container {
    padding: 24px 20px;
  }

  .grid-base {
    grid-template-columns: repeat(4, 1fr);
    gap: 16px;
  }

  .score-badge {
    display: none;
  }

  .clock-zone {
    display: none;
  }

  .brand {
    top: 14px;
    left: 58px;
    padding: 4px 10px;
  }

  .brand-mark {
    width: 26px;
    height: 26px;
    font-size: 15px;
  }

  .brand-word {
    font-size: 15px;
  }

  .brand-cn {
    font-size: 10px;
  }

  .clock-time {
    font-size: 14px;
  }

  .clock-panel {
    padding: 4px 10px;
  }

  .footer-slogan {
    font-size: 24px;
  }

  .footer-top {
    padding: 40px 20px 28px;
    gap: 32px;
  }

  .footer-bottom {
    padding: 14px 20px;
    flex-direction: column;
    align-items: flex-start;
  }
}

/* ===== Reduced Motion ===== */

@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;
  }

  .side-nav {
    transition: none;
  }
}