/* ============ CSS Variables ============ */
:root {
  --color-bg: #0a0e17;
  --color-panel: #12161f;
  --color-glass: rgba(15, 32, 39, 0.72);
  --color-deep: #0f2027;
  --color-cyan: #00e5ff;
  --color-gold: #ffc857;
  --color-red: #e63946;
  --color-silver: #b8c0cc;
  --color-snow: #f2f4f8;

  --font-display: 'DIN Condensed', Impact, 'Arial Narrow', sans-serif;
  --font-body: 'IBM Plex Sans', 'PingFang SC', 'Microsoft YaHei', sans-serif;
  --font-number: 'IBM Plex Mono', 'DIN Alternate', monospace;

  --container-width: 75rem;
  --radius: 8px;
  --transition: 0.25s ease;
}

/* ============ Reset & Base ============ */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

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

body {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  background-color: var(--color-bg);
  background-image:
    linear-gradient(120deg, rgba(0, 229, 255, 0.03) 0%, transparent 40%, transparent 60%, rgba(255, 200, 87, 0.02) 100%),
    radial-gradient(ellipse at 85% -10%, rgba(0, 229, 255, 0.06), transparent 55%),
    radial-gradient(ellipse at 10% 120%, rgba(255, 200, 87, 0.04), transparent 50%);
  background-attachment: fixed;
  color: var(--color-snow);
  font-family: var(--font-body);
  font-size: 1rem;
  line-height: 1.75;
  overflow-x: hidden;
}

body.nav-open {
  overflow: hidden;
}

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

ul, ol {
  list-style: none;
}

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

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

input, select, textarea {
  font: inherit;
}

main {
  display: block;
  flex: 1 0 auto;
  width: 100%;
}

#main-content {
  display: block;
  min-height: 60vh;
}

::selection {
  background: var(--color-cyan);
  color: var(--color-bg);
}

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

::-webkit-scrollbar {
  width: 8px;
  height: 8px;
}

::-webkit-scrollbar-track {
  background: var(--color-bg);
}

::-webkit-scrollbar-thumb {
  background: rgba(184, 192, 204, 0.25);
  border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
  background: rgba(0, 229, 255, 0.5);
}

/* ============ Typography ============ */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-display);
  font-weight: 700;
  line-height: 1.1;
  letter-spacing: 0.02em;
  color: var(--color-snow);
}

p {
  text-wrap: pretty;
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
  border: 0;
}

/* ============ Layout Utilities ============ */
.content-wrap,
.container {
  width: min(var(--container-width), 100% - 2.5rem);
  margin-inline: auto;
}

.section {
  padding-block: 3rem;
}

.section + .section {
  padding-block: 2.5rem;
}

/* ============ Buttons ============ */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.625rem 1.5rem;
  font-family: var(--font-display);
  font-size: 0.9375rem;
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  border-radius: 2px;
  border: 1px solid transparent;
  transition: background var(--transition), color var(--transition), border-color var(--transition), box-shadow var(--transition);
  cursor: pointer;
  text-align: center;
}

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

.btn-primary:hover,
.btn-primary:focus-visible {
  background: var(--color-cyan);
  box-shadow: 0 0 24px rgba(0, 229, 255, 0.3);
}

.btn-ghost {
  border-color: rgba(184, 192, 204, 0.4);
  color: var(--color-snow);
  background: transparent;
}

.btn-ghost:hover,
.btn-ghost:focus-visible {
  border-color: var(--color-cyan);
  color: var(--color-cyan);
}

/* ============ Breadcrumbs ============ */
.breadcrumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.375rem;
  padding-block: 1rem;
  font-size: 0.8125rem;
  color: var(--color-silver);
}

.breadcrumbs a {
  color: var(--color-cyan);
  transition: color var(--transition);
}

.breadcrumbs a:hover,
.breadcrumbs a:focus-visible {
  color: var(--color-snow);
}

.breadcrumbs .sep {
  color: rgba(184, 192, 204, 0.4);
}

.breadcrumbs [aria-current="page"] {
  color: var(--color-gold);
}

/* ============ Editorial Blocks ============ */
.section-label {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-family: var(--font-display);
  font-size: 0.8125rem;
  font-weight: 600;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--color-cyan);
}

.section-label::before {
  content: '';
  width: 1.5rem;
  height: 1px;
  background: var(--color-cyan);
}

.section-title {
  font-family: var(--font-display);
  font-size: clamp(2rem, 5vw, 4rem);
  font-weight: 700;
  line-height: 0.95;
  letter-spacing: 0.02em;
  color: var(--color-snow);
  margin-top: 0.375rem;
}

.section-subtitle {
  color: var(--color-silver);
  font-size: 1rem;
  max-width: 38rem;
  margin-top: 0.75rem;
  line-height: 1.8;
}

/* ============ Cards ============ */
.card {
  background: var(--color-panel);
  border: 1px solid rgba(184, 192, 204, 0.1);
  border-radius: var(--radius);
  padding: 1.5rem;
  transition: border-color 0.3s, box-shadow 0.3s, transform 0.3s;
}

.card:hover,
.card:focus-within {
  border-color: rgba(0, 229, 255, 0.4);
  box-shadow: 0 8px 32px rgba(0, 229, 255, 0.08);
  transform: translateY(-2px);
}

.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(16rem, 1fr));
  gap: 1.25rem;
}

/* ============ Image Frames ============ */
.image-frame {
  position: relative;
  overflow: hidden;
  background: var(--color-panel);
  border: 1px solid rgba(184, 192, 204, 0.15);
  border-radius: var(--radius);
  aspect-ratio: 16 / 9;
}

.image-frame::before {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(0, 229, 255, 0.08), rgba(255, 200, 87, 0.06));
  z-index: 1;
  pointer-events: none;
}

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

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

.image-frame-tall {
  aspect-ratio: 3 / 4;
}

/* ============ Data & Decor ============ */
.data-number {
  font-family: var(--font-number);
  font-size: 2.5rem;
  font-weight: 500;
  line-height: 1;
  color: var(--color-gold);
}

.speed-line {
  background: repeating-linear-gradient(
    -45deg,
    transparent 0,
    transparent 8px,
    rgba(0, 229, 255, 0.12) 8px,
    rgba(0, 229, 255, 0.12) 9px
  );
}

/* ============ Skip Link ============ */
.skip-link {
  position: fixed;
  top: -100%;
  left: 1rem;
  z-index: 300;
  padding: 0.625rem 1.25rem;
  background: var(--color-gold);
  color: var(--color-bg);
  font-weight: 700;
  border-radius: 0 0 4px 4px;
  transition: top 0.2s ease;
}

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

/* ============ Scroll Progress ============ */
.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  width: 0%;
  height: 3px;
  background: linear-gradient(90deg, var(--color-cyan) 0%, var(--color-gold) 70%);
  z-index: 400;
  pointer-events: none;
  transition: width 0.05s linear;
}

/* ============ Header ============ */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(10, 14, 23, 0.97);
  border-bottom: 1px solid rgba(0, 229, 255, 0.12);
  box-shadow: 0 4px 24px rgba(0, 0, 0, 0.35);
  flex-shrink: 0;
}

.site-header::before {
  content: '';
  display: block;
  height: 3px;
  background: linear-gradient(90deg, var(--color-cyan) 0%, var(--color-gold) 55%, var(--color-red) 100%);
}

.header-mast {
  position: relative;
  background: linear-gradient(90deg, rgba(0, 229, 255, 0.04) 0%, transparent 30%, transparent 70%, rgba(255, 200, 87, 0.03) 100%);
}

.header-mast::after {
  content: '';
  position: absolute;
  left: 0;
  right: 0;
  bottom: -1px;
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(0, 229, 255, 0.35), transparent);
  pointer-events: none;
}

.header-inner {
  width: min(var(--container-width), 100% - 2.5rem);
  margin-inline: auto;
  min-height: 4.25rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding-block: 0.625rem;
}

/* ---- Brand ---- */
.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.75rem;
  flex-shrink: 0;
}

.brand-mark {
  width: 2.5rem;
  height: 2.5rem;
  background: linear-gradient(135deg, var(--color-cyan), var(--color-deep));
  clip-path: polygon(50% 0%, 100% 25%, 100% 75%, 50% 100%, 0% 75%, 0% 25%);
  flex-shrink: 0;
  position: relative;
}

.brand-mark::after {
  content: '';
  position: absolute;
  inset: 3px;
  background: var(--color-bg);
  clip-path: polygon(50% 0%, 100% 25%, 100% 75%, 50% 100%, 0% 75%, 0% 25%);
}

.brand-mark::before {
  content: '';
  position: absolute;
  inset: 8px;
  background: var(--color-gold);
  clip-path: polygon(50% 0%, 100% 25%, 100% 75%, 50% 100%, 0% 75%, 0% 25%);
  z-index: 1;
}

.brand-text {
  display: flex;
  flex-direction: column;
  line-height: 1.2;
}

.brand-name {
  font-family: var(--font-display);
  font-size: 1.25rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  color: var(--color-snow);
  white-space: nowrap;
}

.brand-sub {
  font-size: 0.6875rem;
  letter-spacing: 0.12em;
  color: var(--color-cyan);
  text-transform: uppercase;
  white-space: nowrap;
}

/* ---- Header Status ---- */
.header-status {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.3125rem 0.75rem;
  background: rgba(0, 229, 255, 0.06);
  border: 1px solid rgba(0, 229, 255, 0.18);
  border-radius: 2px;
  font-family: var(--font-number);
  font-size: 0.71875rem;
  color: var(--color-silver);
  letter-spacing: 0.06em;
  text-transform: uppercase;
  white-space: nowrap;
}

.status-dot {
  width: 0.5rem;
  height: 0.5rem;
  border-radius: 50%;
  background: var(--color-cyan);
  box-shadow: 0 0 8px rgba(0, 229, 255, 0.8);
  animation: status-pulse 2s ease-in-out infinite;
}

@keyframes status-pulse {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.5; transform: scale(0.75); }
}

/* ---- Quick Tags ---- */
.quick-tags {
  display: flex;
  align-items: center;
  gap: 0.375rem;
  overflow-x: auto;
  scrollbar-width: none;
  -webkit-overflow-scrolling: touch;
  padding: 0.125rem;
}

.quick-tags::-webkit-scrollbar {
  display: none;
}

.tag-link {
  flex-shrink: 0;
  display: inline-flex;
  align-items: center;
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  color: var(--color-silver);
  border: 1px solid rgba(184, 192, 204, 0.2);
  padding: 0.3125rem 0.75rem;
  clip-path: polygon(6px 0, 100% 0, 100% calc(100% - 6px), calc(100% - 6px) 100%, 0 100%, 0 6px);
  background: rgba(18, 22, 31, 0.6);
  transition: color var(--transition), border-color var(--transition), background var(--transition);
}

.tag-link:hover,
.tag-link:focus-visible {
  color: var(--color-gold);
  border-color: var(--color-gold);
  background: rgba(255, 200, 87, 0.08);
}

/* ---- Nav Toggle ---- */
.nav-toggle {
  display: none;
  width: 2.5rem;
  height: 2.5rem;
  flex-shrink: 0;
  border: 1px solid rgba(184, 192, 204, 0.2);
  border-radius: 4px;
  transition: border-color var(--transition), background var(--transition);
}

.nav-toggle:hover,
.nav-toggle:focus-visible {
  border-color: var(--color-cyan);
  background: rgba(0, 229, 255, 0.06);
}

.nav-toggle-line {
  display: block;
  width: 1.25rem;
  height: 2px;
  background: var(--color-snow);
  margin: 3px auto;
  transition: transform 0.3s ease, opacity 0.3s ease;
}

.nav-toggle[aria-expanded="true"] .nav-toggle-line:nth-child(1) {
  transform: translateY(5px) rotate(45deg);
}

.nav-toggle[aria-expanded="true"] .nav-toggle-line:nth-child(2) {
  opacity: 0;
}

.nav-toggle[aria-expanded="true"] .nav-toggle-line:nth-child(3) {
  transform: translateY(-5px) rotate(-45deg);
}

/* ============ Navigation ============ */
.site-nav {
  border-top: 1px solid rgba(184, 192, 204, 0.08);
  background: transparent;
}

.nav-list {
  width: min(var(--container-width), 100% - 2.5rem);
  margin-inline: auto;
  display: flex;
  justify-content: center;
  align-items: stretch;
}

.nav-list a {
  display: block;
  position: relative;
  padding: 0.75rem 1.125rem;
  font-size: 0.875rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  color: var(--color-silver);
  transition: color var(--transition), background var(--transition);
}

.nav-list a:hover,
.nav-list a:focus-visible {
  color: var(--color-snow);
}

.nav-list a::after {
  content: '';
  position: absolute;
  left: 1.125rem;
  right: 1.125rem;
  bottom: 0;
  height: 2px;
  background: var(--color-gold);
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform 0.3s ease;
}

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

.nav-list a[aria-current="page"] {
  color: var(--color-snow);
  background: linear-gradient(to top, rgba(0, 229, 255, 0.08), transparent);
}

/* ============ Footer ============ */
.site-footer {
  position: relative;
  background: linear-gradient(to bottom, var(--color-panel), var(--color-bg));
  border-top: 1px solid rgba(0, 229, 255, 0.12);
  margin-top: 5rem;
  padding-top: 3.5rem;
  flex-shrink: 0;
}

.site-footer::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--color-cyan), var(--color-gold), var(--color-red));
  opacity: 0.7;
}

.footer-inner {
  width: min(var(--container-width), 100% - 2.5rem);
  margin-inline: auto;
  padding-bottom: 2rem;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1.5fr;
  gap: 3rem;
}

.footer-logo {
  display: inline-flex;
  flex-direction: column;
  gap: 0.125rem;
}

.footer-logo-text {
  font-family: var(--font-display);
  font-size: 2rem;
  font-weight: 700;
  line-height: 1;
  letter-spacing: 0.06em;
  color: var(--color-snow);
}

.footer-logo-sub {
  font-size: 0.75rem;
  letter-spacing: 0.14em;
  color: var(--color-cyan);
  text-transform: uppercase;
}

.footer-desc {
  margin-top: 1rem;
  color: var(--color-silver);
  font-size: 0.875rem;
  line-height: 1.8;
  max-width: 30rem;
}

.footer-trust {
  margin-top: 1.25rem;
  font-size: 0.8125rem;
  color: rgba(184, 192, 204, 0.75);
  border-left: 2px solid var(--color-gold);
  padding-left: 0.875rem;
  line-height: 1.7;
}

.footer-heading {
  font-family: var(--font-display);
  font-size: 1.125rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--color-gold);
  padding-bottom: 0.625rem;
  position: relative;
}

.footer-heading::after {
  content: '';
  position: absolute;
  left: 0;
  bottom: 0;
  width: 1.75rem;
  height: 2px;
  background: var(--color-cyan);
}

.footer-col ul {
  margin-top: 1rem;
}

.footer-col ul li {
  margin-bottom: 0.625rem;
  font-size: 0.875rem;
  color: var(--color-silver);
  line-height: 1.6;
}

.footer-col ul li a {
  color: var(--color-silver);
  transition: color var(--transition), padding-left var(--transition);
}

.footer-col ul li a:hover,
.footer-col ul li a:focus-visible {
  color: var(--color-cyan);
  padding-left: 0.375rem;
}

.contact-label {
  display: inline-block;
  width: 3rem;
  margin-right: 0.5rem;
  font-family: var(--font-number);
  font-size: 0.75rem;
  color: rgba(184, 192, 204, 0.6);
  text-transform: uppercase;
  letter-spacing: 0.08em;
}

.footer-bottom {
  border-top: 1px solid rgba(184, 192, 204, 0.1);
  margin-top: 2.5rem;
  padding-top: 1.25rem;
  text-align: center;
}

.footer-bottom p {
  font-size: 0.75rem;
  color: rgba(184, 192, 204, 0.55);
  line-height: 1.8;
}

/* ============ Back Top ============ */
.back-top {
  position: fixed;
  right: 1.25rem;
  bottom: 1.25rem;
  width: 2.75rem;
  height: 2.75rem;
  border-radius: 4px;
  border: 1px solid rgba(0, 229, 255, 0.35);
  background: rgba(10, 14, 23, 0.85);
  color: var(--color-cyan);
  font-size: 1.25rem;
  line-height: 1;
  display: grid;
  place-items: center;
  z-index: 90;
  opacity: 0;
  transform: translateY(1rem);
  pointer-events: none;
  transition: opacity 0.3s, transform 0.3s, border-color 0.3s, color 0.3s;
}

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

.back-top:hover,
.back-top:focus-visible {
  border-color: var(--color-gold);
  color: var(--color-gold);
}

/* ============ Responsive ============ */
@media (max-width: 63.998rem) {
  .header-status {
    display: none;
  }

  .nav-list a {
    padding: 0.75rem 0.875rem;
    font-size: 0.8125rem;
  }

  .footer-grid {
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
  }

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

@media (max-width: 47.998rem) {
  .header-inner {
    flex-wrap: wrap;
    min-height: 0;
    padding-block: 0.625rem;
  }

  .quick-tags {
    order: 2;
    flex: 0 0 100%;
    margin-top: 0.125rem;
  }

  .nav-toggle {
    display: block;
    order: 1;
  }

  .site-nav {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    max-height: 0;
    overflow: hidden;
    opacity: 0;
    visibility: hidden;
    background: rgba(10, 14, 23, 0.97);
    border-top: 1px solid rgba(0, 229, 255, 0.15);
    border-bottom: 1px solid rgba(0, 229, 255, 0.2);
    box-shadow: 0 16px 32px rgba(0, 0, 0, 0.4);
    transition: max-height 0.3s ease, opacity 0.25s ease, visibility 0.3s;
  }

  .site-nav[data-open="true"] {
    max-height: 26rem;
    opacity: 1;
    visibility: visible;
  }

  .nav-list {
    flex-direction: column;
    width: 100%;
    padding: 0.5rem 0;
  }

  .nav-list a {
    padding: 1rem 1.5rem;
    font-size: 1rem;
    border-bottom: 1px solid rgba(184, 192, 204, 0.07);
  }

  .nav-list a::after {
    left: 1.5rem;
    right: 1.5rem;
    top: auto;
    bottom: -1px;
    height: 2px;
  }

  .nav-list a[aria-current="page"] {
    background: linear-gradient(90deg, rgba(0, 229, 255, 0.12), transparent);
  }

  .nav-list a[aria-current="page"]::after {
    right: auto;
    width: 3px;
    height: auto;
    bottom: 0;
    top: 0;
    transform: none;
  }

  .site-footer {
    margin-top: 3rem;
    padding-top: 2.5rem;
  }

  .footer-grid {
    grid-template-columns: 1fr;
    gap: 1.75rem;
  }

  .section {
    padding-block: 2.5rem;
  }
}

@media (min-width: 48rem) {
  .site-nav[data-open="true"] {
    max-height: none;
    opacity: 1;
    visibility: visible;
  }
}

/* ============ 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;
  }

  .status-dot {
    animation: none;
  }
}