/* ===== Reset & Base ===== */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body { min-height: 100vh; background-color: var(--bg-primary); color: var(--text-primary); font-family: var(--font-body); font-size: var(--fs-body); line-height: 1.6; -webkit-font-smoothing: antialiased; }
img, picture, video, canvas, svg { display: block; max-width: 100%; }
input, button, textarea, select { font: inherit; color: inherit; }
a { color: inherit; text-decoration: none; }
ul, ol { list-style: none; }
:focus-visible { outline: 2px solid var(--color-accent); outline-offset: 2px; }
/* ===== Variables ===== */
:root {
  --color-bg-dark: #0B0D17;
  --color-accent: #FF6B35;
  --color-blue-deep: #1A2B4C;
  --color-gold: #D4A017;
  --color-text-primary: #FFFFFF;
  --color-text-secondary: #A0A8B4;
  --color-glass: rgba(255, 255, 255, 0.08);
  --color-divider: #FF6B3544;
  --bg-primary: var(--color-bg-dark);
  --bg-card: var(--color-blue-deep);
  --text-primary: var(--color-text-primary);
  --text-secondary: var(--color-text-secondary);
  --font-heading: 'Arial Black', 'Impact', sans-serif;
  --font-body: 'Merriweather', 'Noto Serif SC', serif;
  --font-data: 'Source Code Pro', 'Courier New', monospace;
  --fs-h1: clamp(3rem, 6vw, 6rem);
  --fs-h2: clamp(2rem, 4vw, 4rem);
  --fs-body: clamp(1rem, 1.4vw, 1.2rem);
  --fs-small: 0.85rem;
  --header-height: 72px;
  --container-max: 1200px;
  --transition-fast: 300ms ease;
}
[data-theme="light"] {
  --bg-primary: #F4F7FA;
  --bg-card: #FFFFFF;
  --text-primary: #0B0D17;
  --text-secondary: #4A5568;
  --color-glass: rgba(0, 0, 0, 0.06);
  --color-divider: #FF6B3566;
}
/* ===== Skip Link ===== */
.skip-link {
  position: absolute; top: -100%; left: 0; z-index: 1000;
  padding: 0.5rem 1rem; background: var(--color-accent); color: #fff;
  font-family: var(--font-heading); font-size: var(--fs-small);
  transition: top var(--transition-fast);
}
.skip-link:focus { top: 0; }
/* ===== Container ===== */
.container { width: 100%; max-width: var(--container-max); margin: 0 auto; padding: 0 1.5rem; }
/* ===== Header ===== */
.site-header {
  position: sticky; top: 0; z-index: 500;
  background: var(--color-blue-deep);
  border-bottom: 3px solid var(--color-accent);
  box-shadow: 0 4px 20px rgba(0,0,0,0.3);
  min-height: var(--header-height);
}
.site-header::before {
  content: ''; position: absolute; top: 0; left: 0; width: 4px; height: 100%;
  background: linear-gradient(180deg, var(--color-accent), var(--color-gold));
  opacity: 0.7;
}
.site-header__container {
  display: flex; align-items: center; flex-wrap: wrap;
  min-height: var(--header-height); position: relative;
}
.site-header__brand {
  display: flex; align-items: center; gap: 0.25rem;
  margin-right: auto; padding: 0.5rem 0;
  position: relative; z-index: 2;
}
.site-header__brand-icon {
  font-family: var(--font-heading); font-size: 2.8rem; font-weight: 900;
  color: var(--color-accent); line-height: 1; letter-spacing: -0.05em;
}
.site-header__brand-name {
  font-family: var(--font-heading); font-size: 1.2rem; font-weight: 900;
  color: var(--text-primary); letter-spacing: -0.5px; line-height: 1;
}
.site-header__theme-toggle {
  background: none; border: 1px solid var(--color-divider); border-radius: 50%;
  width: 40px; height: 40px; display: flex; align-items: center; justify-content: center;
  cursor: pointer; color: var(--color-gold); font-size: 1.2rem;
  transition: background var(--transition-fast), border-color var(--transition-fast);
  margin-right: 0.75rem; order: 1;
}
.site-header__theme-toggle:hover { background: var(--color-glass); border-color: var(--color-gold); }
.theme-icon { line-height: 1; pointer-events: none; }
.site-header__mobile-toggle {
  display: none; flex-direction: column; justify-content: center; gap: 5px;
  background: none; border: none; cursor: pointer; padding: 8px; order: 2;
  min-width: 44px; min-height: 44px;
}
.hamburger-line {
  display: block; width: 26px; height: 2px; background: var(--text-primary);
  border-radius: 2px; transition: transform var(--transition-fast), opacity var(--transition-fast);
}
.site-header__nav { order: 3; flex: 1 1 100%; }
.site-header__nav-list {
  display: flex; flex-wrap: wrap; gap: 0.25rem;
  justify-content: flex-end; padding: 0.5rem 0;
}
.site-header__nav-item { display: inline-flex; }
.site-header__nav-link {
  display: inline-flex; align-items: center; gap: 0.3rem;
  padding: 0.5rem 1rem; font-family: var(--font-data);
  font-size: var(--fs-small); font-weight: 400;
  color: var(--text-secondary); border-bottom: 2px solid transparent;
  transition: color var(--transition-fast), border-color var(--transition-fast);
  white-space: nowrap;
}
.site-header__nav-link:hover, .site-header__nav-link:focus-visible {
  color: var(--color-accent); border-bottom-color: var(--color-accent);
}
.site-header__nav-link[aria-current="page"] {
  color: var(--color-gold); border-bottom-color: var(--color-gold);
  font-weight: 700;
}
.nav-index {
  font-family: var(--font-data); font-size: 0.7rem; color: var(--color-gold);
  opacity: 0.7; letter-spacing: 0.5px;
}
/* ===== Mobile Nav ===== */
@media (max-width: 767px) {
  .site-header__container { align-items: center; }
  .site-header__brand { flex: 0 0 auto; }
  .site-header__theme-toggle { order: 2; margin-right: 0.5rem; }
  .site-header__mobile-toggle { display: flex; order: 3; }
  .site-header__nav {
    order: 4; flex: 1 1 100%; max-height: 0; overflow: hidden;
    transition: max-height 0.45s ease, opacity 0.3s ease, padding 0.3s ease;
    opacity: 0; padding: 0 var(--container-padding, 1.5rem);
  }
  .site-header__nav[data-open] {
    max-height: 500px; opacity: 1; padding: 1rem var(--container-padding, 1.5rem) 1.2rem;
  }
  .site-header__nav-list {
    flex-direction: column; align-items: stretch; gap: 0.25rem;
  }
  .site-header__nav-link {
    padding: 0.75rem 1rem; font-size: 1rem; border-bottom: none;
    border-left: 3px solid transparent; width: 100%;
  }
  .site-header__nav-link:hover, .site-header__nav-link:focus-visible {
    border-left-color: var(--color-accent); background: var(--color-glass);
  }
  .site-header__nav-link[aria-current="page"] {
    border-left-color: var(--color-gold); background: rgba(212,160,23,0.08);
  }
}
@media (min-width: 768px) {
  .site-header__nav { flex: 0 1 auto; order: 3; }
  .site-header__nav-list { flex-wrap: nowrap; }
  .site-header__mobile-toggle { display: none !important; }
}
/* ===== Footer ===== */
.site-footer {
  background: var(--color-bg-dark); color: var(--text-secondary);
  padding: 2.5rem 0 1.5rem; margin-top: 4rem;
  border-top: 1px solid var(--color-divider);
  position: relative;
}
.site-footer__divider {
  position: absolute; top: -1px; left: 0; width: 100%; height: 4px;
  background: linear-gradient(135deg, var(--color-accent), var(--color-gold), transparent 60%);
  clip-path: polygon(0 0, 100% 0, 100% 100%, 0 100%);
  opacity: 0.6;
}
.site-footer__container {
  display: flex; flex-direction: column; gap: 1.5rem;
}
.site-footer__brand {
  display: flex; align-items: center; gap: 0.25rem;
}
.site-footer__brand-icon {
  font-family: var(--font-heading); font-size: 2rem; font-weight: 900;
  color: var(--color-accent); line-height: 1;
}
.site-footer__brand-name {
  font-family: var(--font-heading); font-size: 1rem; font-weight: 900;
  color: var(--text-primary); letter-spacing: -0.5px;
}
.site-footer__info {
  display: flex; flex-wrap: wrap; gap: 2rem; align-items: flex-start;
  justify-content: space-between;
}
.site-footer__nav-list { display: flex; flex-wrap: wrap; gap: 0.25rem 1.5rem; }
.site-footer__nav-link {
  font-family: var(--font-data); font-size: var(--fs-small);
  color: var(--text-secondary); padding: 0.25rem 0;
  border-bottom: 1px solid transparent;
  transition: color var(--transition-fast), border-color var(--transition-fast);
}
.site-footer__nav-link:hover { color: var(--color-accent); border-bottom-color: var(--color-accent); }
.site-footer__contact {
  display: flex; flex-wrap: wrap; gap: 0.5rem 1.5rem;
  font-size: var(--fs-small);
}
.site-footer__contact-item { color: var(--text-secondary); }
.site-footer__contact-item a { color: var(--color-gold); border-bottom: 1px solid transparent; transition: border-color var(--transition-fast); }
.site-footer__contact-item a:hover { border-bottom-color: var(--color-gold); }
.site-footer__icp {
  display: flex; flex-wrap: wrap; gap: 1rem 2rem;
  padding-top: 1.2rem; border-top: 1px solid var(--color-divider);
  font-size: var(--fs-small); color: var(--text-secondary);
}
.site-footer__trust { color: var(--color-text-secondary); opacity: 0.7; }
@media (max-width: 767px) {
  .site-footer__info { flex-direction: column; gap: 1rem; }
  .site-footer__nav-list { gap: 0.25rem 1rem; }
  .site-footer__contact { flex-direction: column; gap: 0.3rem; }
  .site-footer__icp { flex-direction: column; gap: 0.3rem; }
}
/* ===== Common Components ===== */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 0.5rem;
  padding: 0.75rem 1.8rem; font-family: var(--font-heading);
  font-size: var(--fs-small); font-weight: 900; letter-spacing: 0.5px;
  border: 2px solid transparent; border-radius: 4px;
  cursor: pointer; transition: all var(--transition-fast);
  text-transform: uppercase; min-height: 48px;
}
.btn--primary { background: var(--color-accent); color: #fff; border-color: var(--color-accent); }
.btn--primary:hover { background: transparent; color: var(--color-accent); }
.btn--secondary { background: transparent; color: var(--text-primary); border-color: var(--color-blue-deep); }
.btn--secondary:hover { background: var(--color-blue-deep); color: var(--color-accent); border-color: var(--color-accent); }
.glass-panel {
  background: var(--color-glass); backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px); border-radius: 8px; padding: 1.5rem;
}
.breadcrumb { padding: 0.75rem 0; font-size: var(--fs-small); }
.breadcrumb__list { display: flex; flex-wrap: wrap; gap: 0.3rem 0.5rem; }
.breadcrumb__item { display: inline-flex; align-items: center; color: var(--text-secondary); }
.breadcrumb__item + .breadcrumb__item::before {
  content: '/'; margin-right: 0.5rem; color: var(--color-divider);
  font-family: var(--font-data);
}
.breadcrumb__link { color: var(--text-secondary); transition: color var(--transition-fast); }
.breadcrumb__link:hover { color: var(--color-accent); }
.breadcrumb__item:last-child { color: var(--color-gold); font-weight: 700; }
.section { padding: 2rem 0; }
.section__title {
  font-family: var(--font-heading); font-size: var(--fs-h2);
  color: var(--text-primary); letter-spacing: -0.5px; margin-bottom: 1rem;
}
.section__content { max-width: 800px; }
.scroll-top {
  position: fixed; bottom: 2rem; right: 2rem; z-index: 900;
  width: 48px; height: 48px; border-radius: 50%;
  background: var(--color-accent); color: #fff; border: none;
  font-size: 1.4rem; cursor: pointer; opacity: 0; visibility: hidden;
  transform: translateY(20px); transition: opacity 0.4s ease, transform 0.4s ease, visibility 0.4s;
  box-shadow: 0 4px 15px rgba(255,107,53,0.3); display: flex;
  align-items: center; justify-content: center;
}
.scroll-top[data-visible] { opacity: 1; visibility: visible; transform: translateY(0); }
.scroll-top:hover { background: var(--color-gold); transform: translateY(-4px); box-shadow: 0 8px 25px rgba(212,160,23,0.4); }
/* ===== Reduced Motion ===== */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation-duration: 0.01ms !important; transition-duration: 0.01ms !important; scroll-behavior: auto !important; }
  .scroll-top { transition: none !important; }
  .site-header__nav { transition: none !important; }
}
/* ===== Responsive ===== */
@media (max-width: 479px) {
  .container { padding: 0 1rem; }
  .site-header__brand-icon { font-size: 2.2rem; }
  .site-header__brand-name { font-size: 1rem; }
}
@media (min-width: 768px) and (max-width: 1023px) {
  .site-header__nav-link { padding: 0.5rem 0.6rem; font-size: 0.75rem; }
  .nav-index { font-size: 0.6rem; }
}
@media (min-width: 1024px) {
  .site-header__nav-link { padding: 0.5rem 1.2rem; }
}
/* ===== Focus & Accessibility ===== */
[aria-current="page"] { font-weight: 700; }