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

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  background-color: #0A1628;
  color: #F2EFE9;
  font-family: "Roboto", "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
  font-size: 0.9375rem;
  line-height: 1.7;
  min-height: 100vh;
  overflow-x: hidden;
}

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

ul,
ol {
  list-style: none;
}

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

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

:focus-visible {
  outline: 2px solid #FF6B35;
  outline-offset: 3px;
  border-radius: 2px;
  box-shadow: 0 0 0 6px rgba(255, 107, 53, 0.18);
}

::selection {
  background: #FF6B35;
  color: #0A1628;
}

/* ===== CSS Variables ===== */
:root {
  --color-bg: #0A1628;
  --color-bg-deep: #060D18;
  --color-surface: #13273F;
  --color-accent: #FF6B35;
  --color-silver: #C0C6CF;
  --color-grapes: #4C2A6B;
  --color-moss: #5C7A5B;
  --color-terracotta: #A66D42;
  --color-gray: #8B959E;
  --color-text: #F2EFE9;
  --gradient-dark: linear-gradient(135deg, #4C2A6B 0%, #0A1628 100%);
  --font-heading: "Orbitron", "Rajdhani", "Noto Sans SC", "PingFang SC", sans-serif;
  --font-body: "Roboto", "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-mono: "JetBrains Mono", "SFMono-Regular", "Consolas", monospace;
  --container-width: 1200px;
  --header-height: 72px;
  --space-section: clamp(3rem, 7vw, 6rem);
  --transition-timing: cubic-bezier(0.2, 0.7, 0.2, 1);
}

/* ===== Layout primitives ===== */
.container {
  width: min(92%, var(--container-width));
  margin-inline: auto;
}

#main-content {
  display: block;
  min-height: 70vh;
}

.section {
  padding-block: var(--space-section);
}

/* ===== Skip link ===== */
.skip-link {
  position: fixed;
  top: 10px;
  left: 10px;
  background: #FF6B35;
  color: #0A1628;
  padding: 0.6rem 1.2rem;
  font-weight: 700;
  font-size: 0.875rem;
  border-radius: 0 6px 6px 0;
  z-index: 9999;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.3s;
}

.skip-link:focus {
  opacity: 1;
  pointer-events: auto;
  background: #FF6B35;
}

/* ===== Header ===== */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 1000;
  background: transparent;
  border-bottom: 1px solid transparent;
  transition: background-color 0.4s var(--transition-timing),
              border-color 0.4s var(--transition-timing),
              box-shadow 0.4s var(--transition-timing);
}

.site-header.is-sunken {
  background: rgba(10, 22, 40, 0.92);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-bottom-color: rgba(192, 198, 207, 0.15);
  box-shadow: 0 10px 40px -15px rgba(0, 0, 0, 0.7);
}

.header-inner {
  width: min(94%, var(--container-width));
  margin-inline: auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: var(--header-height);
  gap: 1.5rem;
}

.brand-lockup {
  display: inline-flex;
  align-items: baseline;
  gap: 0.6rem;
  white-space: nowrap;
  line-height: 1.2;
}

.brand-index {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.18em;
  color: var(--color-accent);
  text-transform: uppercase;
  border: 1px solid rgba(255, 107, 53, 0.4);
  padding: 0.15rem 0.4rem;
  border-radius: 3px;
  transform: rotate(-2deg);
}

.brand-name {
  font-family: var(--font-heading);
  font-size: 1.1rem;
  font-weight: 600;
  letter-spacing: 0.03em;
  color: var(--color-text);
}

.site-nav {
  display: flex;
  align-items: center;
}

.site-nav ul {
  display: flex;
  align-items: center;
  gap: 0.25rem;
  margin: 0;
  padding: 0;
}

.nav-link {
  display: inline-block;
  padding: 0.6rem 0.9rem;
  font-size: 0.875rem;
  font-weight: 400;
  color: var(--color-silver);
  position: relative;
  transition: color 0.3s;
  border-radius: 2px;
}

.nav-link::after {
  content: "";
  position: absolute;
  left: 0.9rem;
  right: 0.9rem;
  bottom: 0.3rem;
  height: 2px;
  background: var(--color-accent);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 0.3s var(--transition-timing);
}

.nav-link:hover,
.nav-link:focus-visible {
  color: var(--color-text);
}

.nav-link:hover::after,
.nav-link:focus-visible::after {
  transform: scaleX(1);
}

.nav-link[aria-current="page"] {
  color: var(--color-text);
  background: rgba(255, 107, 53, 0.08);
  box-shadow: inset 2px 0 0 var(--color-accent);
}

.nav-link[aria-current="page"]::after {
  transform: scaleX(1);
  background: var(--color-accent);
}

.header-meta {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.status-pill {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-silver);
  border: 1px solid rgba(192, 198, 207, 0.25);
  padding: 0.35rem 0.8rem;
  border-radius: 100px;
  background: rgba(10, 22, 40, 0.5);
}

.signal-dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--color-moss);
  box-shadow: 0 0 6px var(--color-moss);
  animation: signalPulse 2.4s ease-in-out infinite;
}

@keyframes signalPulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.35; }
}

.menu-toggle {
  display: none;
  align-items: center;
  gap: 0.5rem;
  padding: 0.5rem;
  font-size: 0.875rem;
  color: var(--color-text);
  min-width: 48px;
  min-height: 48px;
  justify-content: center;
  border-radius: 4px;
}

.menu-label {
  font-size: 0.8125rem;
  font-weight: 500;
}

.menu-icon {
  position: relative;
  width: 20px;
  height: 2px;
  background: var(--color-accent);
  border-radius: 2px;
  transition: background-color 0.3s;
}

.menu-icon::before,
.menu-icon::after {
  content: "";
  position: absolute;
  left: 0;
  width: 20px;
  height: 2px;
  background: var(--color-accent);
  border-radius: 2px;
  transition: transform 0.3s var(--transition-timing);
}

.menu-icon::before {
  top: -6px;
}

.menu-icon::after {
  top: 6px;
}

.menu-toggle[aria-expanded="true"] .menu-icon {
  background: transparent;
}

.menu-toggle[aria-expanded="true"] .menu-icon::before {
  top: 0;
  transform: rotate(45deg);
}

.menu-toggle[aria-expanded="true"] .menu-icon::after {
  top: 0;
  transform: rotate(-45deg);
}

/* ===== Mobile nav ===== */
@media (max-width: 960px) {
  .site-nav {
    position: fixed;
    inset: 0;
    background: #0A1628;
    z-index: -1;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 5rem 2rem 2rem;
    clip-path: circle(0% at calc(100% - 60px) 30px);
    transition: clip-path 0.6s var(--transition-timing);
    pointer-events: none;
  }

  .site-nav[data-open] {
    clip-path: circle(150% at calc(100% - 60px) 30px);
    pointer-events: auto;
  }

  .site-nav ul {
    flex-direction: column;
    gap: 0.75rem;
    text-align: center;
    width: 100%;
  }

  .nav-link {
    font-size: 1.125rem;
    padding: 1rem 1.5rem;
    display: block;
    color: var(--color-text);
    border-bottom: 1px solid rgba(192, 198, 207, 0.1);
    width: 100%;
  }

  .nav-link::after {
    display: none;
  }

  .nav-link[aria-current="page"] {
    background: rgba(255, 107, 53, 0.12);
    box-shadow: inset 4px 0 0 var(--color-accent);
    color: var(--color-accent);
  }

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

  .status-pill {
    display: none;
  }
}

@media (max-width: 540px) {
  .brand-index {
    display: none;
  }

  .brand-name {
    font-size: 1rem;
  }
}

/* ===== Footer ===== */
.site-footer {
  background: var(--gradient-dark);
  border-top: 1px solid rgba(192, 198, 207, 0.12);
  padding-top: 3rem;
  font-size: 0.875rem;
}

.footer-inner {
  width: min(92%, var(--container-width));
  margin-inline: auto;
  display: grid;
  grid-template-columns: 1.4fr 1fr 1.2fr;
  gap: 2.5rem;
  padding-bottom: 2.5rem;
}

.footer-brand {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  align-items: flex-start;
}

.footer-logo {
  font-family: var(--font-heading);
  font-size: 1.2rem;
  font-weight: 700;
  letter-spacing: 0.02em;
  color: var(--color-text);
  display: flex;
  align-items: baseline;
  gap: 0.4rem;
}

.footer-logo-tail {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  color: var(--color-accent);
  letter-spacing: 0.15em;
}

.footer-description {
  color: var(--color-gray);
  max-width: 34ch;
  line-height: 1.8;
}

.footer-heading {
  font-family: var(--font-heading);
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.14em;
  color: var(--color-accent);
  text-transform: uppercase;
  margin-bottom: 1rem;
  position: relative;
  padding-bottom: 0.5rem;
}

.footer-heading::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -2px;
  width: 28px;
  height: 2px;
  background: var(--color-accent);
}

.footer-nav ul,
.legal-links {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 0.5rem;
  margin: 0;
  padding: 0;
}

.footer-nav a,
.footer-contact a,
.legal-links a {
  color: var(--color-silver);
  transition: color 0.3s, transform 0.3s var(--transition-timing);
  display: inline-block;
  position: relative;
  padding-left: 0;
}

.footer-nav a::before,
.legal-links a::before {
  content: "▹";
  color: var(--color-accent);
  margin-right: 0.4rem;
  opacity: 0;
  transform: translateX(-4px);
  display: inline-block;
  transition: opacity 0.3s, transform 0.3s var(--transition-timing);
}

.footer-nav a:hover,
.footer-nav a:focus-visible,
.footer-contact a:hover,
.footer-contact a:focus-visible,
.legal-links a:hover,
.legal-links a:focus-visible {
  color: var(--color-text);
  transform: translateX(4px);
}

.footer-nav a:hover::before,
.footer-nav a:focus-visible::before,
.legal-links a:hover::before,
.legal-links a:focus-visible::before {
  opacity: 1;
  transform: translateX(0);
}

.footer-contact p,
.footer-contact a {
  color: var(--color-silver);
  line-height: 1.8;
}

.footer-contact a {
  text-decoration: underline;
  text-decoration-color: rgba(255, 107, 53, 0.4);
  text-underline-offset: 3px;
}

.legal-links {
  flex-direction: row;
  flex-wrap: wrap;
  gap: 0.25rem 0.6rem;
}

.footer-bottom {
  border-top: 1px solid rgba(192, 198, 207, 0.1);
  padding-block: 1.2rem;
  text-align: center;
  color: var(--color-gray);
  font-family: var(--font-mono);
  font-size: 0.75rem;
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
  justify-content: center;
  align-items: center;
}

.footer-divider {
  margin: 0 0.6rem;
  color: var(--color-accent);
}

.footer-trust {
  font-family: var(--font-body);
  font-size: 0.75rem;
  color: var(--color-gray);
  opacity: 0.75;
}

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

@media (max-width: 600px) {
  .footer-inner {
    grid-template-columns: 1fr;
    gap: 2rem;
  }

  .footer-bottom {
    padding-inline: 1rem;
  }
}

/* ===== Common button styles ===== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  min-width: 48px;
  min-height: 48px;
  padding: 0.75rem 1.5rem;
  border-radius: 4px;
  font-size: 0.9375rem;
  font-weight: 500;
  transition: background-color 0.3s, border-color 0.3s, box-shadow 0.3s, transform 0.3s var(--transition-timing);
  border: 1px solid transparent;
}

.btn-primary {
  background: var(--color-accent);
  color: #0A1628;
  font-weight: 700;
}

.btn-primary:hover,
.btn-primary:focus-visible {
  background: #ff8255;
  box-shadow: 0 8px 30px rgba(255, 107, 53, 0.3);
  transform: translateY(-2px);
}

.btn-secondary {
  background: transparent;
  color: var(--color-silver);
  border-color: rgba(192, 198, 207, 0.4);
}

.btn-secondary:hover,
.btn-secondary:focus-visible {
  border-color: var(--color-accent);
  color: var(--color-text);
  background: rgba(255, 107, 53, 0.08);
}

.btn-block {
  width: 100%;
}

.btn-sm {
  min-width: unset;
  min-height: 40px;
  padding: 0.45rem 1rem;
  font-size: 0.8125rem;
}

/* ===== Breadcrumb ===== */
.breadcrumb {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 0.5rem;
  font-size: 0.8125rem;
  color: var(--color-gray);
  padding-block: 1rem;
  border-bottom: 1px solid rgba(192, 198, 207, 0.12);
  margin-bottom: 1.5rem;
}

.breadcrumb a {
  color: var(--color-silver);
  transition: color 0.3s;
}

.breadcrumb a:hover,
.breadcrumb a:focus-visible {
  color: var(--color-accent);
}

.breadcrumb .current {
  color: var(--color-text);
  font-family: var(--font-mono);
}

/* ===== Data chip ===== */
.data-chip {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  color: var(--color-silver);
  border: 1px solid rgba(192, 198, 207, 0.3);
  padding: 0.25rem 0.7rem;
  border-radius: 30px;
  background: rgba(10, 22, 40, 0.6);
}

.data-chip.is-live {
  color: var(--color-accent);
  border-color: rgba(255, 107, 53, 0.4);
}

.data-chip.is-synced {
  color: var(--color-moss);
  border-color: rgba(92, 122, 91, 0.4);
}

/* ===== Reveal on scroll ===== */
.reveal-on-scroll {
  opacity: 0;
  transform: transl(0, 18px);
  transition: opacity 0.7s var(--transition-timing), transform 0.7s var(--transition-timing);
}

.reveal-on-scroll.has-revealed {
  opacity: 1;
  transform: none;
}

/* index lines */
.index-line {
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  color: var(--color-silver);
  letter-spacing: 0.08em;
}

/* ===== media placeholder ratio ===== */
.media-block {
  background: var(--gradient-dark);
  border-radius: 8px;
  min-height: 160px;
  position: relative;
  overflow: hidden;
}

.media-block::after {
  content: "IMG";
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.2em;
  color: rgba(255, 255, 255, 0.2);
  background: linear-gradient(135deg, transparent 30%, rgba(255, 255, 255, 0.03) 50%, transparent 60%);
}

.media-block.small {
  min-height: 90px;
}

.media-block.large {
  min-height: 280px;
}

.media-block.round {
  border-radius: 50%;
  aspect-ratio: 1/1;
  min-height: 0;
  width: 120px;
}

/* ===== Utility + spacing ===== */
.text-center {
  text-align: center;
}

.text-muted {
  color: var(--color-gray);
}

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

.mt-1 {
  margin-top: 0.5rem;
}

.mt-2 {
  margin-top: 1rem;
}

.mt-3 {
  margin-top: 2rem;
}

.mb-2 {
  margin-bottom: 1rem;
}

.space-y {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.mx-auto {
  margin-inline: auto;
}

.w-full {
  width: 100%;
}

/* ===== Corner deco lines ===== */
.corner-band {
  position: relative;
}

.corner-band::before,
.corner-band::after {
  content: "";
  position: absolute;
  width: 22px;
  height: 22px;
  border-color: var(--color-accent);
  z-index: 1;
  pointer-events: none;
}

.corner-band::before {
  top: -2px;
  left: -2px;
  border-top: 2px solid;
  border-left: 2px solid;
}

.corner-band::after {
  bottom: -2px;
  right: -2px;
  border-bottom: 2px solid;
  border-right: 2px solid;
}

/* ===== Section tag ===== */
section[data-section] {
  position: relative;
}

.section-tag {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.15em;
  color: var(--color-accent);
  text-transform: uppercase;
  margin-bottom: 1rem;
}

.section-tag::before {
  content: "";
  width: 24px;
  height: 1px;
  background: var(--color-accent);
}

/* ===== scrollbar ===== */
::-webkit-scrollbar {
  width: 10px;
  height: 10px;
}

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

::-webkit-scrollbar-thumb {
  background: var(--color-surface);
  border-radius: 999px;
  border: 2px solid var(--color-bg);
}

::-webkit-scrollbar-thumb:hover {
  background: var(--color-silver);
}

/* ===== Typography ===== */
h1,
h2,
h3,
h4,
h5,
h6 {
  font-family: var(--font-heading);
  line-height: 1.25;
  font-weight: 600;
  color: var(--color-text);
}

h1 {
  font-size: clamp(1.6rem, 4vw, 3rem);
}

h2 {
  font-size: clamp(1.3rem, 3vw, 2.25rem);
}

h3 {
  font-size: clamp(1.1rem, 2.4vw, 1.5rem);
}

.headline-accent {
  color: var(--color-accent);
}

.mono-num {
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  letter-spacing: 0.06em;
  color: var(--color-silver);
}

.text-mono {
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  letter-spacing: 0.05em;
}

/* ===== Tablet / mobile container adjustments ===== */
@media (max-width: 760px) {
  :root {
    --header-height: 64px;
  }

  .header-inner {
    height: 64px;
  }

  .container {
    width: 100%;
    padding-inline: 1.25rem;
  }
}

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

  .reveal-on-scroll {
    opacity: 1;
    transform: none;
    transition: none;
  }

  .signal-dot {
    animation: none;
  }

  .menu-toggle .menu-icon,
  .menu-toggle .menu-icon::before,
  .menu-toggle .menu-icon::after {
    transition: none;
  }

  .site-header,
  .nav-link,
  .btn,
  .footer-nav a,
  .legal-links a,
  .footer-contact a {
    transition: opacity 0.2s, color 0.2s;
  }
}