:root {
  --c-bg: #0a0f2c;
  --c-bg-2: #141a3c;
  --c-accent: #ff5e3a;
  --c-accent-2: #ff9a3d;
  --c-cyan: #00d4ff;
  --c-text: #e8ecff;
  --c-muted: #b0b6cc;
  --c-success: #3ddc84;
  --c-warn: #ffd166;
  --c-line: #2a3358;
  --c-line-strong: #e8ecff;
  --font-sans: "Noto Sans SC", "PingFang SC", "Microsoft YaHei", system-ui, -apple-system, sans-serif;
  --font-mono: "Roboto Mono", "Consolas", "Liberation Mono", ui-monospace, monospace;
  --w-main: 1200px;
  --w-wide: 1440px;
  --pad-x: clamp(16px, 4vw, 32px);
  --gap: clamp(16px, 3vw, 32px);
  --shadow: 6px 6px 0 rgba(0, 0, 0, 0.45);
  --radius: 2px;
}

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

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

body {
  margin: 0;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.65;
  color: var(--c-text);
  background-color: var(--c-bg);
  background-image:
    radial-gradient(circle at 20% 30%, rgba(232, 236, 255, 0.10) 0 1px, transparent 1.6px),
    radial-gradient(circle at 65% 70%, rgba(0, 212, 255, 0.14) 0 1px, transparent 1.6px),
    radial-gradient(circle at 45% 15%, rgba(255, 158, 61, 0.10) 0 1px, transparent 1.6px),
    radial-gradient(circle at 85% 35%, rgba(255, 94, 58, 0.08) 0 1px, transparent 1.6px);
  background-size: 270px 250px, 320px 310px, 220px 260px, 280px 260px;
  background-attachment: fixed;
}

main {
  display: block;
}

#main-content {
  display: block;
  flex: 1 0 auto;
  min-height: 60vh;
  scroll-margin-top: 120px;
}

h1,
h2,
h3,
h4 {
  line-height: 1.15;
  color: var(--c-text);
  margin: 0 0 0.5em;
}

h1 {
  font-size: clamp(36px, 6vw, 72px);
  letter-spacing: -0.02em;
}

h2 {
  font-size: clamp(28px, 4vw, 44px);
}

h3 {
  font-size: clamp(20px, 2.6vw, 28px);
}

p {
  margin-top: 0;
}

a {
  color: var(--c-cyan);
  text-decoration-thickness: 2px;
  text-underline-offset: 4px;
}

a:hover {
  color: var(--c-accent-2);
}

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

::selection {
  background: var(--c-accent);
  color: #fff;
}

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

.site-progress {
  position: fixed;
  top: 0;
  left: 0;
  width: 0%;
  max-width: 100%;
  height: 3px;
  z-index: 3000;
  border: 0;
  pointer-events: none;
  background: linear-gradient(90deg, var(--c-accent) 0%, var(--c-accent-2) 60%, var(--c-cyan) 100%);
  box-shadow: 0 0 12px rgba(255, 94, 58, 0.6);
  transition: width 0.06s linear;
}

.skip-link {
  position: fixed;
  top: 12px;
  left: 12px;
  z-index: 4000;
  padding: 12px 18px;
  background: var(--c-accent);
  color: #fff;
  font-weight: 800;
  text-decoration: none;
  border: 2px solid #0a0f2c;
  box-shadow: 4px 4px 0 rgba(0, 0, 0, 0.5);
  transform: translateY(-160px);
  transition: transform 0.2s ease;
}

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

.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  padding-top: 4px;
  background: rgba(10, 15, 44, 0.94);
  -webkit-backdrop-filter: blur(8px);
  backdrop-filter: blur(8px);
}

.header-top {
  max-width: var(--w-main);
  margin: 0 auto;
  padding: 8px var(--pad-x);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  border-bottom: 1px solid var(--c-line);
}

.site-badge {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-size: 13px;
  font-weight: 600;
  color: var(--c-muted);
  letter-spacing: 0.04em;
  margin: 0;
}

.site-badge__dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--c-accent);
  box-shadow: 0 0 0 3px rgba(255, 94, 58, 0.15), 0 0 10px var(--c-accent);
  flex: none;
}

.site-badge__text {
  color: var(--c-text);
}

.site-badge__divider {
  color: var(--c-muted);
  font-family: var(--font-mono);
}

.site-badge__slogan {
  color: var(--c-accent-2);
  font-weight: 800;
}

.header-meta {
  display: inline-flex;
  align-items: center;
  gap: 12px;
}

.header-meta__note {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--c-cyan);
  letter-spacing: 0.1em;
}

.header-main {
  max-width: var(--w-main);
  margin: 0 auto;
  padding: 12px var(--pad-x) 14px;
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: center;
  gap: 24px;
}

.site-brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: var(--c-text);
  text-decoration: none;
  position: relative;
}

.site-brand:hover {
  color: var(--c-text);
}

.site-brand__mark {
  width: 40px;
  height: 40px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(135deg, var(--c-accent), var(--c-accent-2));
  color: #0a0f2c;
  font-size: 20px;
  font-weight: 900;
  border: 2px solid #0a0f2c;
  box-shadow: 3px 3px 0 var(--c-cyan);
  transform: rotate(-4deg);
  transition: transform 0.2s ease;
  flex: none;
}

.site-brand:hover .site-brand__mark {
  transform: rotate(4deg) scale(1.04);
}

.site-brand__name {
  font-size: 22px;
  font-weight: 900;
  letter-spacing: 0.02em;
  line-height: 1.1;
}

.site-brand__index {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.2em;
  color: var(--c-muted);
  border: 1px solid var(--c-line);
  padding: 2px 6px;
  margin-top: 4px;
}

.nav-toggle {
  display: none;
  align-items: center;
  gap: 8px;
  background: var(--c-bg-2);
  border: 2px solid var(--c-line-strong);
  color: var(--c-text);
  font: inherit;
  font-weight: 800;
  padding: 10px 14px;
  cursor: pointer;
  box-shadow: 3px 3px 0 rgba(0, 0, 0, 0.4);
}

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

.nav-toggle__label {
  font-size: 14px;
}

.nav-toggle__icon {
  width: 18px;
  height: 14px;
  position: relative;
  flex: none;
}

.nav-toggle__icon span {
  position: absolute;
  left: 0;
  width: 100%;
  height: 2px;
  background: var(--c-text);
  transition: transform 0.2s ease, opacity 0.2s ease;
}

.nav-toggle__icon span:nth-child(1) {
  top: 0;
}

.nav-toggle__icon span:nth-child(2) {
  top: 6px;
}

.nav-toggle__icon span:nth-child(3) {
  top: 12px;
}

.nav-toggle.is-open .nav-toggle__icon span:nth-child(1) {
  transform: translateY(6px) rotate(45deg);
}

.nav-toggle.is-open .nav-toggle__icon span:nth-child(2) {
  opacity: 0;
}

.nav-toggle.is-open .nav-toggle__icon span:nth-child(3) {
  transform: translateY(-6px) rotate(-45deg);
}

.site-nav {
  justify-self: end;
  position: relative;
}

.site-nav__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 2px;
}

.site-nav__item {
  margin: 0;
  list-style: none;
}

.site-nav__link {
  display: inline-flex;
  align-items: baseline;
  gap: 6px;
  padding: 8px 10px;
  color: var(--c-text);
  text-decoration: none;
  font-size: 14px;
  font-weight: 700;
  line-height: 1.2;
  border: 1px solid transparent;
  border-bottom: 2px solid transparent;
  border-radius: var(--radius);
  transition: color 0.15s ease, background 0.15s ease, border-color 0.15s ease;
}

.site-nav__link::before {
  content: attr(data-index);
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 500;
  color: var(--c-cyan);
}

.site-nav__link:hover {
  color: var(--c-accent-2);
  border-color: var(--c-line);
  background: rgba(255, 94, 58, 0.06);
}

.site-nav__link[aria-current="page"] {
  color: #fff;
  background: linear-gradient(135deg, rgba(255, 94, 58, 0.92), rgba(255, 158, 61, 0.78));
  border-color: #0a0f2c;
  box-shadow: 3px 3px 0 rgba(0, 0, 0, 0.35);
}

.site-nav__link[aria-current="page"]::before {
  color: #0a0f2c;
}

.site-nav__foot {
  display: none;
}

.site-footer {
  position: relative;
  margin-top: auto;
  background: var(--c-bg-2);
}

.site-footer::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--c-accent) 0%, var(--c-accent-2) 50%, var(--c-cyan) 100%);
  z-index: 1;
}

.footer-banner {
  max-width: var(--w-main);
  margin: 0 auto;
  padding: 48px var(--pad-x) 8px;
  display: grid;
  gap: 8px;
}

.footer-banner__index {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.24em;
  color: var(--c-cyan);
}

.footer-banner__text {
  margin: 0;
  font-size: clamp(20px, 3vw, 30px);
  font-weight: 900;
  line-height: 1.25;
  max-width: 36ch;
}

.footer-banner__tagline {
  margin: 0;
  max-width: 60ch;
  color: var(--c-muted);
  font-size: 14px;
}

.footer-grid {
  max-width: var(--w-main);
  margin: 0 auto;
  padding: 32px var(--pad-x) 24px;
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr;
  gap: 32px;
}

.footer-brand {
  display: grid;
  align-content: start;
  gap: 12px;
}

.footer-brand .site-brand {
  flex-wrap: wrap;
}

.site-brand--footer .site-brand__mark {
  width: 52px;
  height: 52px;
  font-size: 26px;
}

.site-brand--footer .site-brand__name {
  font-size: 26px;
}

.footer-brand__note {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--c-muted);
  letter-spacing: 0.2em;
}

.footer-brand__contact {
  margin: 0;
  font-size: 13px;
  color: var(--c-muted);
  line-height: 1.8;
  max-width: 42ch;
  word-break: break-word;
}

.footer-links {
  display: grid;
  align-content: start;
  gap: 12px;
}

.footer-heading {
  margin: 0;
  font-size: 14px;
  font-weight: 800;
  letter-spacing: 0.12em;
  color: var(--c-accent-2);
  border-bottom: 1px solid var(--c-line);
  padding-bottom: 8px;
}

.footer-links__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 8px;
}

.footer-links__list a {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  color: var(--c-text);
  text-decoration: none;
  font-size: 14px;
  transition: color 0.15s ease, padding-left 0.15s ease;
}

.footer-links__list a::before {
  content: "→";
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--c-accent);
  transition: transform 0.15s ease;
}

.footer-links__list a:hover {
  color: var(--c-accent-2);
  padding-left: 4px;
}

.footer-links__list a:hover::before {
  transform: translateX(3px);
}

.footer-bottom {
  border-top: 1px solid var(--c-line);
}

.footer-bottom__inner {
  max-width: var(--w-main);
  margin: 0 auto;
  padding: 16px var(--pad-x) 20px;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 8px 24px;
  font-size: 12px;
  color: var(--c-muted);
}

.footer-bottom__copy {
  margin: 0;
}

.footer-bottom__icp {
  margin: 0;
  font-family: var(--font-mono);
  letter-spacing: 0.08em;
}

.site-container {
  width: 100%;
  max-width: var(--w-main);
  margin: 0 auto;
  padding: 0 var(--pad-x);
}

.page-main {
  max-width: var(--w-main);
  margin: 0 auto;
  padding: 32px var(--pad-x) 64px;
}

.breadcrumbs {
  display: flex;
  flex-wrap: wrap;
  padding: 16px 0;
  margin: 0 0 24px;
  border-bottom: 1px solid var(--c-line);
  font-size: 13px;
}

.breadcrumbs ol {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.breadcrumbs li + li::before {
  content: "/";
  margin-right: 8px;
  color: var(--c-muted);
}

.breadcrumbs a {
  color: var(--c-muted);
  text-decoration: none;
}

.breadcrumbs a:hover {
  color: var(--c-accent-2);
}

.breadcrumbs [aria-current="page"] {
  color: var(--c-text);
  font-weight: 700;
}

.section {
  margin: 64px 0;
}

.section-head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 8px 16px;
  padding-bottom: 12px;
  border-bottom: 2px solid var(--c-line-strong);
  margin-bottom: 24px;
}

.section-index {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.2em;
  color: var(--c-cyan);
}

.section-title {
  margin: 0;
  font-size: clamp(22px, 3.2vw, 36px);
  line-height: 1.15;
}

.section-more {
  margin-left: auto;
  font-size: 13px;
  color: var(--c-muted);
  text-decoration: none;
}

.section-more:hover {
  color: var(--c-accent);
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 22px;
  font-size: 14px;
  font-weight: 800;
  line-height: 1.2;
  color: var(--c-text);
  text-decoration: none;
  background: transparent;
  border: 2px solid var(--c-line-strong);
  border-radius: var(--radius);
  cursor: pointer;
  box-shadow: 4px 4px 0 rgba(0, 0, 0, 0.4);
  transition: transform 0.12s ease, box-shadow 0.12s ease, background 0.15s ease, border-color 0.15s ease;
}

.btn:hover {
  transform: translate(-1px, -1px);
  box-shadow: 5px 5px 0 rgba(0, 0, 0, 0.45);
  color: var(--c-text);
}

.btn:active {
  transform: translate(1px, 1px);
  box-shadow: 2px 2px 0 rgba(0, 0, 0, 0.5);
}

.btn-primary {
  background: linear-gradient(135deg, var(--c-accent), var(--c-accent-2));
  color: #fff;
  border-color: #0a0f2c;
}

.btn-primary:hover {
  color: #fff;
}

.btn-ghost {
  background: transparent;
}

.btn-sm {
  padding: 8px 14px;
  font-size: 12px;
  box-shadow: 3px 3px 0 rgba(0, 0, 0, 0.4);
}

.card {
  background: var(--c-bg-2);
  border: 2px solid var(--c-line-strong);
  box-shadow: var(--shadow);
  padding: 24px;
  border-radius: var(--radius);
}

.card--accent {
  border-color: var(--c-accent);
}

.card--cyan {
  border-color: var(--c-cyan);
}

.chip {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 10px;
  font-size: 12px;
  font-weight: 700;
  color: var(--c-accent-2);
  background: rgba(255, 94, 58, 0.08);
  border: 1px solid var(--c-line);
  border-radius: var(--radius);
}

.chip--cyan {
  color: var(--c-cyan);
  background: rgba(0, 212, 255, 0.08);
}

.chip--success {
  color: var(--c-success);
  background: rgba(61, 220, 132, 0.08);
}

.grid {
  display: grid;
  gap: var(--grid-gap, 20px);
  grid-template-columns: repeat(var(--grid-cols, 1), 1fr);
}

.grid--1 {
  --grid-cols: 1;
}

.grid--2 {
  --grid-cols: 2;
}

.grid--3 {
  --grid-cols: 3;
}

.grid--4 {
  --grid-cols: 4;
}

.grid--auto {
  grid-template-columns: repeat(auto-fit, minmax(min(100%, 240px), 1fr));
}

.media-frame {
  position: relative;
  margin: 0;
  aspect-ratio: 16 / 9;
  background: var(--c-bg-2);
  border: 2px solid var(--c-line-strong);
  box-shadow: var(--shadow);
  overflow: hidden;
}

.media-frame::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: 1;
  pointer-events: none;
  background:
    radial-gradient(circle at 70% 20%, rgba(0, 212, 255, 0.22), transparent 45%),
    radial-gradient(circle at 15% 80%, rgba(255, 94, 58, 0.20), transparent 45%),
    linear-gradient(120deg, rgba(255, 158, 64, 0.08), transparent 60%);
}

.media-frame img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  z-index: 0;
}

.media-frame figcaption {
  position: absolute;
  left: 0;
  bottom: 0;
  z-index: 2;
  padding: 8px 14px;
  background: rgba(10, 15, 44, 0.9);
  border-top: 2px solid var(--c-line-strong);
  color: var(--c-text);
  font-size: 12px;
  letter-spacing: 0.05em;
}

.media-frame--wide {
  aspect-ratio: 21 / 9;
}

.media-frame--tall {
  aspect-ratio: 4 / 5;
}

.gradient-line {
  height: 3px;
  margin: 32px 0;
  border: 0;
  background: linear-gradient(90deg, var(--c-accent), var(--c-accent-2), var(--c-cyan));
}

.js-enabled [data-reveal] {
  opacity: 0;
  transform: translateY(14px);
  transition: opacity 0.5s ease, transform 0.5s ease;
}

.js-enabled [data-reveal][data-visible] {
  opacity: 1;
  transform: none;
}

.nav-open {
  overflow: hidden;
}

@media (max-width: 900px) {
  .footer-grid {
    grid-template-columns: 1fr 1fr;
  }

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

  .grid--4,
  .grid--3 {
    --grid-cols: 2;
  }
}

@media (max-width: 860px) {
  .nav-toggle {
    display: inline-flex;
  }

  .site-nav {
    position: fixed;
    top: 0;
    right: 0;
    bottom: 0;
    width: min(88vw, 360px);
    height: 100vh;
    overflow-y: auto;
    background: rgba(20, 26, 60, 0.98);
    border-left: 2px solid var(--c-line-strong);
    box-shadow: -8px 0 24px rgba(0, 0, 0, 0.4);
    padding: 88px 24px 32px;
    z-index: 1500;
    transform: translateX(110%);
    transition: transform 0.28s ease;
  }

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

  .site-nav__list {
    display: grid;
    gap: 4px;
    justify-content: stretch;
  }

  .site-nav__link {
    font-size: 18px;
    padding: 12px 8px;
    border-bottom: 1px solid var(--c-line);
    border-radius: 0;
  }

  .site-nav__link[aria-current="page"] {
    background: linear-gradient(135deg, rgba(255, 94, 58, 0.92), rgba(255, 158, 61, 0.78));
  }

  .site-nav__foot {
    display: grid;
    gap: 6px;
    margin-top: 24px;
    padding-top: 16px;
    border-top: 2px solid var(--c-line-strong);
    font-family: var(--font-mono);
    font-size: 12px;
    color: var(--c-muted);
  }
}

@media (max-width: 760px) {
  .header-meta__note {
    display: none;
  }

  .site-badge__divider {
    display: none;
  }
}

@media (max-width: 620px) {
  .site-brand__name {
    font-size: 18px;
  }

  .site-brand__index {
    display: none;
  }

  .section {
    margin: 40px 0;
  }

  .footer-grid {
    grid-template-columns: 1fr;
    gap: 24px;
  }

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

@media (max-width: 560px) {
  .grid--2,
  .grid--3,
  .grid--4 {
    --grid-cols: 1;
  }
}

@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;
  }

  .skip-link,
  .site-progress,
  .site-nav,
  .nav-toggle__icon span {
    transition: none;
  }

  .js-enabled [data-reveal] {
    opacity: 1 !important;
    transform: none !important;
  }
}