:root {
  --bg: #0A0E14;
  --bg-panel: #111722;
  --accent: #00C8FF;
  --accent-2: #39FF14;
  --title: #E0F7FF;
  --text: #9BA8B8;
  --border: rgba(0, 200, 255, 0.3);
  --warning: #FFB020;
  --grad: linear-gradient(135deg, #00C8FF 0%, #39FF14 100%);
  --font-head: 'Oswald', 'Arial Narrow', 'PingFang SC', 'Microsoft YaHei', sans-serif;
  --font-body: 'Inter', 'PingFang SC', 'Microsoft YaHei', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-data: 'Barlow Condensed', 'Arial Narrow', 'Roboto Condensed', 'DIN Alternate', sans-serif;
  --header-h: 72px;
  --radius: 2px;
}

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

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
  scrollbar-color: var(--bg-panel) var(--bg);
}

body {
  margin: 0;
  background-color: var(--bg);
  background-image:
    radial-gradient(circle at 85% 8%, rgba(0, 200, 255, 0.07) 0%, transparent 30%),
    radial-gradient(circle at 12% 82%, rgba(57, 255, 20, 0.05) 0%, transparent 26%);
  background-attachment: fixed;
  color: var(--text);
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3, h4 {
  margin: 0;
  color: var(--title);
  font-family: var(--font-head);
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.02em;
  line-height: 1.15;
}

p { margin: 0 0 1.2em; }

a {
  color: var(--accent);
  text-decoration: none;
}

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

ul, ol { list-style: none; margin: 0; padding: 0; }

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

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

::selection { background: rgba(0, 200, 255, 0.28); color: #fff; }

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

::-webkit-scrollbar { width: 10px; height: 10px; }
::-webkit-scrollbar-track { background: var(--bg); }
::-webkit-scrollbar-thumb { background: var(--bg-panel); border: 1px solid var(--border); border-radius: 4px; }

#main-content {
  display: block;
  padding-top: var(--header-h);
}

.container {
  max-width: 1280px;
  margin: 0 auto;
  padding-left: 24px;
  padding-right: 24px;
}

.skip-link {
  position: fixed;
  top: -100px;
  left: 16px;
  z-index: 300;
  padding: 10px 18px;
  background: var(--accent);
  color: #081016;
  font-weight: 700;
  font-size: 14px;
  border-radius: 0 0 6px 6px;
  text-decoration: none;
  transition: top 0.2s;
}

.skip-link:focus { top: 0; }

.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 200;
  background: rgba(10, 14, 20, 0.92);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
}

.site-header::before {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image: repeating-linear-gradient(115deg, transparent 0 22px, rgba(0, 200, 255, 0.025) 22px 23px, transparent 23px 44px);
}

.header-frame {
  position: relative;
  height: var(--header-h);
  display: flex;
  align-items: center;
  gap: 32px;
  border-left: 1px solid var(--border);
  border-right: 1px solid var(--border);
}

.header-frame::before {
  content: "";
  position: absolute;
  left: -1px;
  top: -1px;
  width: 12px;
  height: 12px;
  background: var(--accent-2);
  clip-path: polygon(0 0, 100% 0, 0 100%);
}

.header-frame::after {
  content: "";
  position: absolute;
  right: -1px;
  bottom: -1px;
  width: 12px;
  height: 12px;
  background: var(--accent);
  clip-path: polygon(100% 100%, 0 100%, 100% 0);
}

.brand {
  position: relative;
  display: flex;
  align-items: baseline;
  gap: 10px;
  flex-shrink: 0;
  padding-left: 18px;
  font-family: var(--font-head);
  font-size: 20px;
  font-weight: 800;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--title);
  text-decoration: none;
  line-height: 1;
  white-space: nowrap;
}

.brand::before {
  content: "";
  position: absolute;
  left: 0;
  top: 2px;
  bottom: 2px;
  width: 6px;
  background: var(--grad);
  transform: skewX(-18deg);
}

.brand span {
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.22em;
  color: var(--accent);
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 24px;
  margin-left: auto;
}

.site-links {
  display: flex;
  gap: 2px;
}

.site-links a {
  display: block;
  padding: 10px 12px;
  color: var(--text);
  font-size: 14px;
  font-weight: 600;
  letter-spacing: 0.05em;
  text-decoration: none;
  position: relative;
  transition: color 0.2s;
}

.site-links a::after {
  content: "";
  position: absolute;
  left: 12px;
  right: 12px;
  bottom: 4px;
  height: 2px;
  background: var(--grad);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 0.25s;
}

.site-links a:hover,
.site-links a:focus-visible {
  color: var(--title);
}

.site-links a:hover::after,
.site-links a:focus-visible::after,
.site-links a[aria-current="page"]::after {
  transform: scaleX(1);
}

.site-links a[aria-current="page"] {
  color: var(--accent);
}

.header-tools {
  display: flex;
  align-items: center;
  gap: 8px;
}

.lang-switch {
  display: inline-flex;
  border: 1px solid var(--border);
  border-radius: 4px;
  overflow: hidden;
}

.lang-switch button {
  padding: 6px 12px;
  background: transparent;
  border: none;
  color: var(--text);
  font-size: 13px;
  font-weight: 600;
  line-height: 1;
  transition: background 0.2s, color 0.2s;
}

.lang-switch button[aria-pressed="true"] {
  background: rgba(0, 200, 255, 0.14);
  color: var(--accent);
}

.lang-switch button:hover {
  color: var(--title);
}

.quick-fav {
  padding: 7px 12px;
  border: 1px solid var(--border);
  border-radius: 4px;
  background: transparent;
  color: var(--accent);
  font-size: 13px;
  font-weight: 600;
  line-height: 1;
  transition: background 0.2s, border-color 0.2s;
}

.quick-fav:hover {
  background: rgba(0, 200, 255, 0.1);
  border-color: var(--accent);
  color: var(--accent);
}

.nav-toggle {
  display: none;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 0;
  width: 42px;
  height: 42px;
  padding: 8px;
  border: 1px solid var(--border);
  border-radius: 4px;
  background: transparent;
  color: var(--title);
  transition: border-color 0.2s, background 0.2s;
}

.nav-toggle:hover {
  background: rgba(0, 200, 255, 0.08);
  border-color: var(--accent);
}

.nav-toggle .icon-bar {
  display: block;
  width: 18px;
  height: 2px;
  margin: 3px 0;
  background: currentColor;
}

.scroll-progress {
  position: absolute;
  left: 0;
  bottom: -1px;
  width: 0;
  height: 3px;
  background: var(--accent-2);
  box-shadow: 0 0 12px rgba(57, 255, 20, 0.8);
  z-index: 2;
}

.top-button {
  position: fixed;
  right: 24px;
  bottom: 24px;
  z-index: 260;
  width: 46px;
  height: 46px;
  border: 1px solid var(--accent);
  border-radius: 4px;
  background: var(--bg-panel);
  color: var(--accent);
  font-size: 20px;
  line-height: 1;
  opacity: 0;
  pointer-events: none;
  transform: translateY(10px);
  transition: opacity 0.3s, transform 0.3s, background 0.2s;
}

.top-button:hover {
  background: rgba(0, 200, 255, 0.12);
}

.top-button[data-visible] {
  opacity: 1;
  pointer-events: auto;
  transform: translateY(0);
}

.fav-toast {
  position: fixed;
  right: 24px;
  bottom: 84px;
  z-index: 270;
  padding: 12px 18px;
  background: var(--bg-panel);
  border: 1px solid var(--accent);
  border-radius: 4px;
  color: var(--title);
  font-size: 14px;
  box-shadow: 0 12px 32px rgba(0, 0, 0, 0.4);
  opacity: 0;
  pointer-events: none;
  transform: translateY(8px);
  transition: opacity 0.3s, transform 0.3s;
}

.fav-toast[data-show] {
  opacity: 1;
  transform: translateY(0);
}

.site-footer {
  position: relative;
  background: linear-gradient(180deg, var(--bg-panel) 0%, #0C111A 100%);
  border-top: 1px solid var(--border);
  overflow: hidden;
}

.site-footer::before {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  opacity: 0.45;
  background-image: repeating-linear-gradient(115deg, transparent 0 18px, rgba(0, 200, 255, 0.03) 18px 19px, transparent 19px 38px);
}

.footer-accent {
  height: 8px;
  background: var(--grad);
  clip-path: polygon(0 0, 88% 0, 62% 100%, 0 100%);
  position: relative;
  z-index: 1;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr 1.2fr;
  gap: 48px;
  padding-top: 64px;
  padding-bottom: 48px;
  position: relative;
  z-index: 1;
}

.footer-brand .brand {
  font-size: 22px;
}

.footer-desc {
  max-width: 42ch;
  margin: 18px 0 14px;
  font-size: 14px;
  line-height: 1.7;
}

.footer-tag {
  display: inline-block;
  padding-left: 10px;
  border-left: 3px solid var(--accent-2);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.2em;
  color: var(--accent);
}

.footer-col h3 {
  font-size: 14px;
  letter-spacing: 0.12em;
  margin-bottom: 16px;
  padding-bottom: 8px;
  position: relative;
}

.footer-col h3::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: 24px;
  height: 2px;
  background: var(--grad);
}

.footer-col ul {
  display: grid;
  gap: 8px;
}

.footer-col a {
  color: var(--text);
  font-size: 14px;
  text-decoration: none;
  transition: color 0.2s, padding-left 0.2s;
}

.footer-col a:hover,
.footer-col a:focus-visible {
  color: var(--accent);
  padding-left: 6px;
}

.footer-note {
  margin-top: 16px;
  padding-left: 10px;
  border-left: 2px solid var(--border);
  font-size: 13px;
  color: var(--text);
  max-width: 34ch;
}

.footer-contact p {
  margin: 6px 0;
  font-size: 14px;
}

.footer-bottom {
  position: relative;
  z-index: 1;
  padding: 20px 0;
  border-top: 1px solid var(--border);
}

.footer-bottom .container {
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 8px;
  color: var(--text);
  font-size: 13px;
}

.section {
  padding: 72px 0;
}

.section--tight {
  padding: 36px 0;
}

.section--loose {
  padding: 104px 0;
}

.section--divide {
  border-top: 1px solid var(--border);
}

.section-head {
  display: flex;
  align-items: baseline;
  gap: 20px;
  margin-bottom: 36px;
}

.section-no {
  font-family: var(--font-head);
  font-size: clamp(40px, 6vw, 72px);
  font-weight: 800;
  line-height: 1;
  color: var(--bg);
  -webkit-text-stroke: 1px var(--accent);
  letter-spacing: 0.02em;
  flex-shrink: 0;
}

.section-title {
  font-size: clamp(22px, 3vw, 34px);
  margin: 0;
}

.section-title::after {
  content: "";
  display: inline-block;
  width: 42px;
  height: 4px;
  margin-left: 18px;
  background: var(--grad);
  transform: skewX(-20deg);
  vertical-align: middle;
}

.page-head {
  padding: 64px 0 44px;
  margin-bottom: 40px;
  border-bottom: 1px solid var(--border);
  position: relative;
}

.page-head::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -1px;
  width: 72px;
  height: 2px;
  background: var(--grad);
}

.page-title {
  margin: 0 0 12px;
  font-size: clamp(36px, 6vw, 64px);
  line-height: 1.02;
  letter-spacing: 0.01em;
  background: linear-gradient(120deg, var(--title) 30%, var(--accent) 100%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.page-subtitle {
  max-width: 56ch;
  color: var(--text);
  font-size: 17px;
  margin: 0;
}

.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin-bottom: 32px;
  padding: 0;
  font-size: 13px;
  color: var(--text);
}

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

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

.bc-sep {
  color: var(--border);
  pointer-events: none;
}

.panel {
  background: var(--bg-panel);
  border: 1px solid var(--border);
  padding: 28px;
  clip-path: polygon(0 0, calc(100% - 22px) 0, 100% 22px, 100% 100%, 22px 100%, 0 calc(100% - 22px));
}

.panel--accent {
  border-color: var(--accent);
  box-shadow: 0 0 0 1px rgba(0, 200, 255, 0.12), 0 16px 32px rgba(0, 0, 0, 0.3);
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 13px 24px;
  background: var(--grad);
  color: #081016;
  font-family: var(--font-head);
  font-size: 14px;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  text-decoration: none;
  border: none;
  border-radius: 0;
  clip-path: polygon(0 0, calc(100% - 14px) 0, 100% 14px, 100% 100%, 14px 100%, 0 calc(100% - 14px));
  transition: filter 0.2s, transform 0.2s;
}

.btn:hover {
  filter: brightness(1.15);
  transform: translateY(-2px);
  color: #081016;
}

.btn:focus-visible {
  box-shadow: inset 0 0 0 3px rgba(0, 0, 0, 0.3);
}

.btn--ghost {
  background: transparent;
  color: var(--accent);
  border: 1px solid currentColor;
}

.btn--ghost:hover {
  background: rgba(0, 200, 255, 0.08);
  color: var(--accent);
}

.tag {
  display: inline-block;
  padding: 4px 10px;
  background: rgba(0, 200, 255, 0.12);
  color: var(--accent);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  border-left: 2px solid var(--accent);
}

.tag--green {
  background: rgba(57, 255, 20, 0.1);
  color: var(--accent-2);
  border-left-color: var(--accent-2);
}

.media {
  position: relative;
  background: var(--bg-panel);
  border: 1px solid var(--border);
  overflow: hidden;
}

.media::before {
  content: "";
  display: block;
  padding-top: 56.25%;
}

.media img,
.media .media-inner {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.media--portrait::before { padding-top: 130%; }
.media--square::before { padding-top: 100%; }
.media--wide::before { padding-top: 42%; }

.preview-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.preview-card {
  display: block;
  position: relative;
  padding: 28px;
  background: var(--bg-panel);
  border: 1px solid var(--border);
  color: var(--text);
  text-decoration: none;
  clip-path: polygon(0 0, calc(100% - 26px) 0, 100% 26px, 100% 100%, 26px 100%, 0 calc(100% - 26px));
  transition: transform 0.25s, border-color 0.25s, box-shadow 0.25s;
}

.preview-card:hover {
  transform: translate(-4px, -4px);
  border-color: var(--accent);
  box-shadow: 10px 10px 0 rgba(0, 200, 255, 0.06);
  color: var(--text);
}

.preview-card:focus-visible {
  box-shadow: inset 0 0 0 3px rgba(0, 200, 255, 0.7);
}

.preview-card-index {
  font-family: var(--font-head);
  font-size: 56px;
  font-weight: 800;
  line-height: 1;
  color: var(--bg);
  -webkit-text-stroke: 1px var(--accent);
  margin-bottom: 16px;
}

.preview-card-title {
  color: var(--title);
  font-family: var(--font-head);
  font-size: 20px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.03em;
  margin-bottom: 8px;
}

.preview-card-text {
  font-size: 14px;
  line-height: 1.6;
  margin-bottom: 0;
}

.text-accent { color: var(--accent); }
.text-muted { color: var(--text); }
.text-warn { color: var(--warning); }

.num {
  font-family: var(--font-data);
  font-weight: 600;
  letter-spacing: 0.01em;
  color: var(--accent);
}

@media (max-width: 1024px) {
  .container {
    padding-left: 20px;
    padding-right: 20px;
  }

  .footer-grid {
    grid-template-columns: 1fr 1fr;
    gap: 40px 32px;
  }

  .site-links a {
    padding: 8px 10px;
  }

  .header-frame {
    gap: 18px;
  }

  .header-tools {
    gap: 6px;
  }

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

@media (max-width: 920px) {
  :root {
    --header-h: 64px;
  }

  .nav-toggle {
    display: flex;
  }

  .site-nav {
    position: fixed;
    top: var(--header-h);
    left: 0;
    right: 0;
    z-index: 190;
    flex-direction: column;
    align-items: stretch;
    gap: 18px;
    margin: 0;
    padding: 16px 20px 24px;
    background: rgba(10, 14, 20, 0.98);
    border-bottom: 1px solid var(--border);
    box-shadow: 0 24px 48px rgba(0, 0, 0, 0.5);
    transform: translateY(-10px);
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.25s ease, transform 0.25s ease;
  }

  .site-nav[data-open] {
    transform: translateY(0);
    opacity: 1;
    pointer-events: auto;
  }

  .site-links {
    flex-direction: column;
    gap: 2px;
  }

  .site-links a {
    padding: 12px 10px;
    font-size: 16px;
    border-left: 3px solid transparent;
  }

  .site-links a::after {
    display: none;
  }

  .site-links a:hover,
  .site-links a[aria-current="page"] {
    border-left-color: var(--accent);
    background: rgba(0, 200, 255, 0.06);
    color: var(--accent);
  }

  .header-tools {
    display: flex;
  }

  .brand span {
    letter-spacing: 0.16em;
    font-size: 10px;
  }
}

@media (max-width: 640px) {
  .container {
    padding-left: 16px;
    padding-right: 16px;
  }

  .header-frame {
    border-left: none;
    border-right: none;
    gap: 10px;
  }

  .header-frame::before,
  .header-frame::after {
    display: none;
  }

  .brand {
    font-size: 18px;
    padding-left: 14px;
  }

  .brand span {
    display: none;
  }

  .footer-grid {
    grid-template-columns: 1fr;
    gap: 36px;
    padding-top: 48px;
    padding-bottom: 36px;
  }

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

  .section {
    padding: 48px 0;
  }

  .section--loose {
    padding: 72px 0;
  }

  .section-head {
    gap: 14px;
    margin-bottom: 24px;
  }

  .section-title::after {
    width: 28px;
    height: 3px;
    margin-left: 10px;
  }

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

  .top-button {
    right: 16px;
    bottom: 16px;
  }

  .fav-toast {
    right: 16px;
  }

  .page-head {
    padding: 40px 0 28px;
    margin-bottom: 28px;
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    animation: none !important;
    transition: none !important;
  }
}