:root {
  --primary-900: #0A1E3C;
  --primary-700: #0D3B6E;
  --primary-500: #1B4D8E;
  --accent-500: #F25C05;
  --accent-300: #FF7A50;
  --neutral-100: #FFFFFF;
  --neutral-200: #F1F4F8;
  --neutral-400: #A5B1C2;
  --neutral-600: #4E5D6E;
  --neutral-800: #1E2A36;
  --success: #2ECC71;
  --warning: #F1C40F;
  --font-heading: "Noto Sans SC", "PingFang SC", sans-serif;
  --font-body: "Noto Sans SC", "Microsoft YaHei", sans-serif;
  --font-mono: "JetBrains Mono", "Roboto Mono", monospace;
  --header-height: 72px;
  --container-max: 1200px;
}

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

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-height) + 1rem);
}

body {
  padding-top: var(--header-height);
  font-family: var(--font-body);
  font-weight: 400;
  font-size: 1rem;
  line-height: 1.7;
  color: var(--neutral-600);
  background: var(--neutral-200);
}

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

a {
  color: var(--primary-500);
  text-decoration: none;
  transition: color 0.2s ease;
}

a:hover {
  color: var(--accent-500);
}

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

ul, ol {
  list-style: none;
}

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  font-weight: 900;
  line-height: 1.3;
  color: var(--neutral-800);
}

.container {
  width: 100%;
  max-width: var(--container-max);
  margin-inline: auto;
  padding-inline: 2rem;
}

body {
  background-image:
    linear-gradient(135deg, rgba(10, 30, 60, 0.03) 25%, transparent 25%),
    linear-gradient(225deg, rgba(10, 30, 60, 0.03) 25%, transparent 25%);
  background-size: 24px 24px;
}

#main-content {
  min-height: 60vh;
  scroll-margin-top: calc(var(--header-height) + 1rem);
}

.skip-link {
  position: fixed;
  top: 0.5rem;
  left: 0.5rem;
  z-index: 3000;
  background: var(--accent-500);
  color: #fff;
  font-weight: 700;
  font-size: 0.9rem;
  padding: 0.6rem 1.2rem;
  clip-path: polygon(8px 0, 100% 0, calc(100% - 8px) 100%, 0 100%);
  transform: translateY(-180%);
  transition: transform 0.2s ease;
}

.skip-link:focus {
  transform: translateY(0);
  outline: none;
}

.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  height: 3px;
  width: 0;
  z-index: 2500;
  background: linear-gradient(90deg, var(--accent-300), var(--accent-500));
  box-shadow: 0 0 8px rgba(242, 92, 5, 0.45);
  transition: width 0.1s linear;
}

.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1800;
  background: rgba(10, 30, 60, 0.94);
  -webkit-backdrop-filter: blur(12px);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.18);
}

.site-header__stripe {
  position: absolute;
  top: 0;
  left: 0;
  width: 52%;
  height: 4px;
  background: var(--accent-500);
  transform: skewX(-30deg);
  transform-origin: left top;
  z-index: 1;
}

.site-header__inner {
  position: relative;
  z-index: 2;
  display: flex;
  align-items: center;
  gap: 2rem;
  height: var(--header-height);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  color: #fff;
  font-family: var(--font-heading);
  font-weight: 900;
  font-size: 1.25rem;
  line-height: 1;
  white-space: nowrap;
}

.brand:hover {
  color: var(--accent-300);
}

.brand__mark {
  width: 34px;
  height: 34px;
  padding: 4px;
  color: #fff;
  background: var(--accent-500);
  border-radius: 50%;
  box-shadow: 0 0 0 2px rgba(255, 255, 255, 0.25);
  flex-shrink: 0;
}

.brand__name {
  display: inline-block;
}

.nav-toggle {
  display: none;
  flex-direction: column;
  align-items: center;
  gap: 0.25rem;
  margin-left: auto;
  padding: 0.4rem;
  color: #fff;
}

.nav-toggle__box {
  width: 22px;
  height: 16px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.nav-toggle__bar {
  height: 2px;
  width: 100%;
  background: currentColor;
  border-radius: 2px;
  transition: transform 0.2s ease, opacity 0.2s 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);
}

.nav-toggle__text {
  font-size: 0.7rem;
  letter-spacing: 0.08em;
}

.site-nav {
  margin-left: auto;
}

.site-nav__list {
  display: flex;
  align-items: center;
  gap: 0.25rem;
}

.site-nav__item {
  margin: 0;
}

.site-nav__link {
  position: relative;
  display: inline-block;
  padding: 0.5rem 0.85rem;
  font-family: var(--font-body);
  font-weight: 700;
  font-size: 0.95rem;
  line-height: 1.4;
  color: rgba(255, 255, 255, 0.9);
  white-space: nowrap;
}

.site-nav__link::after {
  content: "";
  position: absolute;
  left: 0.85rem;
  right: 0.85rem;
  bottom: 0;
  height: 2px;
  background: var(--accent-500);
  transform: scaleX(0) skewX(-30deg);
  transform-origin: right center;
  transition: transform 0.22s ease;
}

.site-nav__link:hover {
  color: #fff;
}

.site-nav__link:hover::after,
.site-nav__link[aria-current="page"]::after {
  transform: scaleX(1) skewX(-30deg);
  transform-origin: left center;
}

.site-nav__link[aria-current="page"] {
  color: #fff;
}

.site-footer {
  position: relative;
  background: var(--primary-900);
  color: rgba(255, 255, 255, 0.78);
  margin-top: 5rem;
  overflow: hidden;
}

.site-footer::before {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(13, 59, 110, 0.5) 0%, transparent 55%);
  pointer-events: none;
}

.site-footer__stripe {
  position: absolute;
  top: 0;
  right: 0;
  width: 48%;
  height: 4px;
  background: var(--accent-500);
  transform: skewX(30deg);
  transform-origin: right top;
  z-index: 1;
}

.site-footer__inner {
  position: relative;
  z-index: 2;
  display: grid;
  grid-template-columns: 1.6fr 1fr 1.2fr 1fr;
  gap: 2.5rem;
  padding-block: 3.5rem 2.5rem;
}

.site-footer__col--brand {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
}

.site-footer__heading {
  position: relative;
  color: #fff;
  font-size: 1rem;
  font-weight: 700;
  margin-bottom: 1.1rem;
  padding-bottom: 0.5rem;
  letter-spacing: 0.04em;
}

.site-footer__heading::before {
  content: "";
  display: inline-block;
  width: 16px;
  height: 4px;
  background: var(--accent-500);
  margin-right: 0.5rem;
  transform: skewX(-30deg);
  vertical-align: middle;
}

.site-footer ul.footer-nav,
.site-footer ul.contact-list {
  margin: 0;
  padding: 0;
}

.footer-nav {
  display: grid;
  gap: 0.4rem;
}

.footer-nav__link {
  display: inline-block;
  padding-block: 0.15rem;
  color: rgba(255, 255, 255, 0.8);
  font-size: 0.95rem;
}

.footer-nav__link:hover {
  color: var(--accent-300);
}

.contact-list {
  display: grid;
  gap: 0.55rem;
}

.contact-list__item {
  display: block;
  color: rgba(255, 255, 255, 0.72);
  font-size: 0.92rem;
  line-height: 1.55;
}

.contact-list__link {
  color: var(--accent-300);
  font-weight: 700;
}

.contact-list__link:hover {
  color: var(--accent-500);
}

.site-footer__desc {
  margin-top: 1rem;
  font-size: 0.95rem;
  line-height: 1.7;
  color: rgba(255, 255, 255, 0.72);
}

.site-footer__trust {
  margin-top: 0.75rem;
  font-size: 0.85rem;
  color: var(--neutral-400);
}

.site-footer__bottom {
  position: relative;
  z-index: 2;
  font-family: var(--font-mono);
  font-size: 0.85rem;
}

.site-footer__bottom-inner {
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 0.5rem;
  border-top: 1px solid rgba(255, 255, 255, 0.12);
  padding-block: 1.5rem;
}

.site-footer__copyright,
.site-footer__icp {
  margin: 0;
  color: rgba(255, 255, 255, 0.6);
}

.page-title {
  font-family: var(--font-heading);
  font-weight: 900;
  font-size: clamp(2rem, 4vw, 3rem);
  line-height: 1.15;
  color: var(--neutral-800);
  letter-spacing: -0.02em;
}

.page-lead {
  font-size: 1.125rem;
  line-height: 1.8;
  color: var(--neutral-600);
  max-width: 60ch;
  margin-top: 0.6rem;
}

.hero-title {
  font-family: var(--font-heading);
  font-weight: 900;
  font-size: clamp(2.5rem, 6vw, 4.5rem);
  line-height: 1.05;
  letter-spacing: -0.02em;
  color: var(--neutral-800);
}

.section-heading {
  font-family: var(--font-heading);
  font-weight: 900;
  font-size: clamp(1.5rem, 3vw, 2rem);
  line-height: 1.2;
  color: var(--neutral-800);
}

.breadcrumbs {
  margin-bottom: 1.5rem;
}

.breadcrumbs__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.5rem;
  margin: 0;
  padding: 0;
}

.breadcrumbs__item {
  display: inline-flex;
  align-items: center;
  font-family: var(--font-mono);
  font-size: 0.85rem;
  color: var(--neutral-400);
}

.breadcrumbs__item + .breadcrumbs__item::before {
  content: "/";
  margin-right: 0.5rem;
  color: var(--neutral-400);
}

.breadcrumbs__link {
  color: var(--primary-500);
  font-weight: 700;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  background: var(--accent-500);
  color: #fff;
  font-family: var(--font-body);
  font-weight: 700;
  font-size: 0.95rem;
  padding: 0.8rem 1.6rem;
  border: 2px solid transparent;
  cursor: pointer;
  text-decoration: none;
  clip-path: polygon(12px 0, 100% 0, 100% calc(100% - 12px), calc(100% - 12px) 100%, 0 100%, 0 12px);
  transition: background 0.2s ease, transform 0.2s ease;
}

.btn:hover {
  background: var(--accent-300);
  color: #fff;
}

.btn:active {
  transform: translateY(1px);
}

.btn--dark {
  background: var(--primary-900);
}

.btn--dark:hover {
  background: var(--primary-700);
  color: #fff;
}

.btn--ghost {
  background: transparent;
  border-color: var(--primary-500);
  color: var(--primary-500);
  clip-path: polygon(12px 0, 100% 0, 100% calc(100% - 12px), calc(100% - 12px) 100%, 0 100%, 0 12px);
}

.btn--ghost:hover {
  background: var(--primary-500);
  color: #fff;
}

.card {
  position: relative;
  background: var(--neutral-100);
  border: 1px solid rgba(10, 30, 60, 0.08);
  padding: 1.5rem;
  box-shadow: 0 8px 24px rgba(10, 30, 60, 0.05);
}

.card--dark {
  background: var(--primary-900);
  border-color: var(--primary-700);
  color: rgba(255, 255, 255, 0.85);
}

.card--dark h1,
.card--dark h2,
.card--dark h3,
.card--dark h4,
.card--dark .card__title {
  color: #fff;
}

.card__title {
  font-family: var(--font-heading);
  font-weight: 900;
  font-size: 1.2rem;
  color: var(--neutral-800);
  margin-bottom: 0.5rem;
}

.glass {
  background: rgba(255, 255, 255, 0.78);
  -webkit-backdrop-filter: blur(12px);
  backdrop-filter: blur(12px);
  border: 1px solid rgba(255, 255, 255, 0.5);
  box-shadow: 0 10px 32px rgba(10, 30, 60, 0.08);
}

.grid {
  display: grid;
  gap: 1.5rem;
}

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

.grid--3 {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

.section-label {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  background: var(--primary-700);
  color: #fff;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.08em;
  padding: 0.35rem 0.8rem 0.35rem 0.4rem;
  clip-path: polygon(10px 0, 100% 0, calc(100% - 10px) 100%, 0 100%);
  line-height: 1.4;
}

.index-num {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--accent-500);
}

.section-label .index-num {
  color: var(--accent-300);
  font-size: 0.7rem;
}

.stripe {
  height: 4px;
  background: var(--accent-500);
  transform: skewX(-30deg);
  transform-origin: left center;
}

.image-placeholder {
  --aspect-ratio: 4 / 3;
  position: relative;
  display: flex;
  align-items: flex-end;
  aspect-ratio: var(--aspect-ratio);
  background:
    linear-gradient(135deg, rgba(13, 59, 110, 0.85), rgba(10, 30, 60, 0.95)),
    repeating-linear-gradient(45deg, rgba(255, 255, 255, 0.06) 0 1px, transparent 1px 8px);
  color: #fff;
  overflow: hidden;
}

.image-placeholder::after {
  content: attr(data-caption);
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  padding: 1.5rem 1rem 0.75rem;
  background: linear-gradient(transparent, rgba(10, 30, 60, 0.72));
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: rgba(255, 255, 255, 0.85);
}

.data-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.95rem;
  background: var(--neutral-100);
}

.data-table th,
.data-table td {
  padding: 0.75rem 1rem;
  text-align: left;
  border-bottom: 1px solid var(--neutral-200);
}

.data-table th {
  background: var(--primary-900);
  color: #fff;
  font-family: var(--font-mono);
  font-size: 0.85rem;
  letter-spacing: 0.04em;
}

.data-table tbody tr:nth-child(even) {
  background: var(--neutral-200);
}

.tabbed__list {
  display: flex;
  flex-wrap: wrap;
  gap: 0.25rem;
  border-bottom: 2px solid var(--neutral-200);
  margin-bottom: -1px;
}

.tabbed__trigger {
  padding: 0.65rem 1.4rem;
  background: var(--neutral-200);
  color: var(--neutral-600);
  font-weight: 700;
  font-size: 0.95rem;
  border: 0;
  cursor: pointer;
}

.tabbed__trigger[aria-selected="true"] {
  background: var(--primary-900);
  color: #fff;
}

.tabbed__panel {
  padding: 2rem;
  background: var(--neutral-100);
  border: 1px solid var(--neutral-200);
  border-top: 0;
}

:focus-visible {
  outline: 3px solid var(--accent-300);
  outline-offset: 2px;
}

@media (max-width: 960px) {
  .site-nav {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    margin-left: 0;
    background: var(--primary-900);
    padding: 0 1.25rem 1.25rem;
    border-top: 2px solid var(--accent-500);
    opacity: 0;
    visibility: hidden;
    transform: translateY(-10px);
    transition: opacity 0.22s ease, transform 0.22s ease, visibility 0.22s;
    max-height: calc(100vh - var(--header-height));
    overflow-y: auto;
  }

  .site-nav[data-open="true"] {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
  }

  .site-nav__list {
    flex-direction: column;
    align-items: stretch;
    gap: 0;
  }

  .site-nav__item {
    border-bottom: 1px solid rgba(255, 255, 255, 0.08);
  }

  .site-nav__item:last-child {
    border-bottom: 0;
  }

  .site-nav__link {
    display: block;
    width: 100%;
    padding: 0.85rem 0;
    color: #fff;
  }

  .site-nav__link::after {
    display: none;
  }

  .site-nav__link[aria-current="page"] {
    color: var(--accent-300);
    border-left: 3px solid var(--accent-500);
    padding-left: 0.85rem;
  }

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

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

@media (max-width: 768px) {
  .container {
    padding-inline: 1.25rem;
  }

  .site-header__inner {
    gap: 1rem;
  }

  .brand {
    font-size: 1.1rem;
  }

  .brand__mark {
    width: 30px;
    height: 30px;
  }

  .tabbed__panel {
    padding: 1.25rem;
  }
}

@media (max-width: 640px) {
  .site-footer__inner {
    grid-template-columns: 1fr;
    gap: 1.5rem;
  }

  .site-footer__bottom-inner {
    flex-direction: column;
    align-items: flex-start;
  }

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

  .data-table th,
  .data-table td {
    padding: 0.55rem 0.7rem;
  }
}

@media (max-width: 480px) {
  .nav-toggle__text {
    display: none;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    scroll-behavior: auto !important;
  }

  .scroll-progress {
    transition: none;
  }

  .site-nav {
    transition: none;
  }
}