/* ===== RESET ===== */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { font-size: 16px; scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body { font-family: "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif; font-weight: 300; line-height: 1.7; color: #1A1A1A; background: #F2F2F2; min-height: 100vh; }
ul, ol { list-style: none; }
a { text-decoration: none; color: inherit; }
img, svg { display: block; max-width: 100%; }
button { font: inherit; border: none; background: none; cursor: pointer; color: inherit; }
input { font: inherit; border: none; background: none; color: inherit; }
:focus-visible { outline: 2px solid #D4AF37; outline-offset: 2px; }
@media (prefers-reduced-motion: reduce) { *, *::before, *::after { transition-duration: 0.01ms !important; animation-duration: 0.01ms !important; } }

/* ===== CSS VARIABLES ===== */
:root {
  --color-primary: #E60012;
  --color-gold: #D4AF37;
  --color-black: #1A1A1A;
  --color-deep-teal: #0D3B4F;
  --color-wine: #7B241C;
  --color-indigo: #4B0082;
  --color-light-gray: #F2F2F2;
  --color-white: #FFFFFF;
  --rail-width: 80px;
  --header-top-height: 60px;
  --font-body: "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-headline: "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
  --scale-ratio: 1.25;
  --space-xs: 0.25rem;
  --space-sm: 0.5rem;
  --space-md: 1rem;
  --space-lg: 2rem;
  --space-xl: 3rem;
  --max-width: 1200px;
  --transition-fast: 0.2s ease;
  --transition-smooth: 0.35s ease;
}

/* ===== SKIP LINK ===== */
.skip-link {
  position: absolute;
  top: -100%;
  left: var(--space-md);
  background: var(--color-gold);
  color: var(--color-black);
  padding: var(--space-sm) var(--space-md);
  font-weight: 700;
  font-size: 0.875rem;
  z-index: 10000;
  border-radius: 0 0 4px 4px;
  transition: top var(--transition-fast);
}
.skip-link:focus { top: 0; }

/* ===== SCROLL PROGRESS ===== */
.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  width: 0%;
  height: 3px;
  background: linear-gradient(90deg, var(--color-gold), var(--color-primary));
  z-index: 9999;
  transition: width 0.05s linear;
  pointer-events: none;
}
@media (prefers-reduced-motion: reduce) {
  .scroll-progress { display: none; }
}

/* ===== SITE HEADER ===== */
.site-header {
  position: relative;
  display: flex;
  flex-direction: column;
  width: 100%;
  background: var(--color-black);
}

/* ===== NAV RAIL ===== */
.nav-rail {
  position: fixed;
  top: 0;
  left: 0;
  width: var(--rail-width);
  height: 100vh;
  background: var(--color-black);
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: var(--space-md) 0;
  z-index: 1000;
  border-right: 1px solid rgba(212, 175, 55, 0.15);
  transition: transform var(--transition-smooth);
}
.rail-brand {
  font-size: 1.4rem;
  font-weight: 700;
  color: var(--color-gold);
  letter-spacing: 0.1em;
  writing-mode: vertical-rl;
  text-orientation: upright;
  margin-bottom: var(--space-lg);
  line-height: 1.2;
  opacity: 0.9;
}
.rail-track {
  position: absolute;
  left: 50%;
  top: 100px;
  bottom: 80px;
  width: 1px;
  background: linear-gradient(to bottom, transparent, var(--color-gold), transparent);
  transform: translateX(-50%);
  opacity: 0.25;
  pointer-events: none;
}
.nav-list {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.25rem;
  width: 100%;
  flex: 1;
  justify-content: center;
}
.nav-item {
  width: 100%;
  display: flex;
  justify-content: center;
}
.nav-link {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.15rem;
  padding: 0.5rem 0.25rem;
  width: 100%;
  text-align: center;
  transition: background var(--transition-fast), color var(--transition-fast);
  border-radius: 4px;
  position: relative;
}
.nav-dot {
  display: block;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: rgba(212, 175, 55, 0.4);
  transition: background var(--transition-fast), transform var(--transition-fast);
  flex-shrink: 0;
}
.nav-label {
  font-size: 0.625rem;
  font-weight: 300;
  color: rgba(255, 255, 255, 0.6);
  letter-spacing: 0.04em;
  transition: color var(--transition-fast), font-weight var(--transition-fast);
  line-height: 1.2;
}
.nav-link:hover .nav-dot {
  background: var(--color-gold);
  transform: scale(1.3);
}
.nav-link:hover .nav-label {
  color: var(--color-gold);
}
.nav-link[aria-current="page"] .nav-dot {
  background: var(--color-primary);
  transform: scale(1.4);
  box-shadow: 0 0 8px rgba(230, 0, 18, 0.5);
}
.nav-link[aria-current="page"] .nav-label {
  color: var(--color-white);
  font-weight: 700;
}
/* ===== HEADER TOP ===== */
.header-top {
  margin-left: var(--rail-width);
  background: var(--color-primary);
  padding: 0 var(--space-lg);
  height: var(--header-top-height);
  display: flex;
  align-items: center;
  justify-content: space-between;
  position: relative;
  z-index: 900;
  box-shadow: 0 2px 12px rgba(0, 0, 0, 0.15);
}
.header-brand {
  display: flex;
  align-items: center;
}
.brand-full {
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--color-white);
  letter-spacing: 0.06em;
}
.brand-sub {
  font-size: 0.7rem;
  font-weight: 300;
  color: var(--color-gold);
  margin-left: var(--space-sm);
  letter-spacing: 0.12em;
  opacity: 0.85;
}
.header-actions {
  display: flex;
  align-items: center;
  gap: var(--space-md);
}
.search-toggle {
  width: 36px;
  height: 36px;
  display: flex;
  align-items: center;
  justify-content: center;
  border: 1px solid rgba(255, 255, 255, 0.25);
  border-radius: 50%;
  color: var(--color-white);
  font-size: 1.3rem;
  transition: background var(--transition-fast), border-color var(--transition-fast);
}
.search-toggle:hover {
  background: rgba(255, 255, 255, 0.1);
  border-color: var(--color-gold);
}
.search-box {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  overflow: hidden;
  max-width: 0;
  opacity: 0;
  transition: max-width var(--transition-smooth), opacity var(--transition-smooth);
  background: rgba(255, 255, 255, 0.12);
  border-radius: 24px;
}
.search-box[aria-hidden="false"] {
  max-width: 240px;
  opacity: 1;
  padding: 0.2rem 0.2rem 0.2rem var(--space-md);
}
.search-input {
  width: 100%;
  background: transparent;
  color: var(--color-white);
  font-size: 0.85rem;
  padding: 0.35rem 0;
  min-width: 100px;
}
.search-input::placeholder { color: rgba(255, 255, 255, 0.5); }
.search-close {
  width: 28px;
  height: 28px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-white);
  font-size: 0.85rem;
  border-radius: 50%;
  transition: background var(--transition-fast);
}
.search-close:hover { background: rgba(255, 255, 255, 0.15); }

.btn-gold {
  display: inline-flex;
  align-items: center;
  padding: 0.4rem 1.2rem;
  border: 1px solid var(--color-gold);
  color: var(--color-gold);
  font-size: 0.8rem;
  font-weight: 600;
  border-radius: 24px;
  transition: background var(--transition-fast), color var(--transition-fast);
  letter-spacing: 0.04em;
}
.btn-gold:hover {
  background: var(--color-gold);
  color: var(--color-black);
}

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 4px;
  width: 36px;
  height: 36px;
  align-items: center;
  justify-content: center;
  border: 1px solid rgba(255, 255, 255, 0.25);
  border-radius: 4px;
  padding: 6px;
}
.hamburger-line {
  display: block;
  width: 20px;
  height: 2px;
  background: var(--color-white);
  border-radius: 2px;
  transition: transform var(--transition-fast), opacity var(--transition-fast);
}

/* ===== MAIN CONTENT ===== */
#main-content {
  margin-left: var(--rail-width);
  min-height: 60vh;
  background: var(--color-light-gray);
  position: relative;
  z-index: 1;
}

/* ===== SITE FOOTER ===== */
.site-footer {
  margin-left: var(--rail-width);
  background: var(--color-black);
  color: rgba(255, 255, 255, 0.7);
  padding: var(--space-xl) var(--space-lg) var(--space-lg);
  border-top: 2px solid var(--color-gold);
}
.footer-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: var(--space-lg);
}
.footer-brand {
  display: flex;
  flex-direction: column;
  gap: var(--space-sm);
  align-items: flex-start;
}
.footer-logo {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--color-white);
  letter-spacing: 0.06em;
}
.footer-tagline {
  font-size: 0.85rem;
  color: var(--color-gold);
  font-weight: 300;
  letter-spacing: 0.04em;
}
.footer-links {
  display: flex;
  gap: var(--space-lg);
  flex-wrap: wrap;
  border-top: 1px solid rgba(255, 255, 255, 0.08);
  padding-top: var(--space-md);
}
.footer-link {
  font-size: 0.85rem;
  color: rgba(255, 255, 255, 0.5);
  transition: color var(--transition-fast);
  position: relative;
}
.footer-link::after {
  content: "";
  position: absolute;
  bottom: -2px;
  left: 0;
  width: 0;
  height: 1px;
  background: var(--color-gold);
  transition: width var(--transition-fast);
}
.footer-link:hover { color: var(--color-gold); }
.footer-link:hover::after { width: 100%; }
.footer-contact {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-md) var(--space-lg);
  font-size: 0.8rem;
  color: rgba(255, 255, 255, 0.35);
  border-top: 1px solid rgba(255, 255, 255, 0.06);
  padding-top: var(--space-md);
}
.contact-item { line-height: 1.6; }
.contact-item.icp { font-weight: 300; letter-spacing: 0.04em; }
.footer-copy {
  font-size: 0.75rem;
  color: rgba(255, 255, 255, 0.2);
  border-top: 1px solid rgba(255, 255, 255, 0.04);
  padding-top: var(--space-md);
  text-align: center;
}

/* ===== RESPONSIVE ===== */
@media (max-width: 1023px) {
  :root { --rail-width: 0px; --header-top-height: 56px; }
  .nav-rail {
    transform: translateX(-100%);
    width: 280px;
    box-shadow: 4px 0 32px rgba(0,0,0,0.5);
    padding: var(--space-lg) var(--space-md);
    border-right: none;
  }
  .nav-rail[data-open] {
    transform: translateX(0);
  }
  .rail-brand {
    writing-mode: horizontal-tb;
    text-orientation: mixed;
    font-size: 1.6rem;
    margin-bottom: var(--space-md);
    align-self: flex-start;
  }
  .rail-track { display: none; }
  .nav-list {
    gap: 0.5rem;
    align-items: stretch;
    justify-content: flex-start;
    margin-top: var(--space-md);
  }
  .nav-item { width: 100%; }
  .nav-link {
    flex-direction: row;
    gap: var(--space-md);
    padding: 0.75rem var(--space-md);
    border-radius: 6px;
    justify-content: flex-start;
  }
  .nav-dot { width: 8px; height: 8px; flex-shrink: 0; }
  .nav-label { font-size: 0.9rem; font-weight: 400; color: rgba(255,255,255,0.7); }
  .nav-link[aria-current="page"] { background: rgba(230,0,18,0.15); }
  .nav-link[aria-current="page"] .nav-label { color: var(--color-white); }
  .header-top {
    margin-left: 0;
    padding: 0 var(--space-md);
  }
  .brand-full { font-size: 1rem; }
  .brand-sub { font-size: 0.6rem; }
  .nav-toggle { display: flex; }
  .action-download { display: none; }
  #main-content { margin-left: 0; }
  .site-footer { margin-left: 0; padding: var(--space-lg) var(--space-md); }
  .search-box[aria-hidden="false"] { max-width: 180px; }
  .header-actions { gap: var(--space-sm); }
}

@media (max-width: 600px) {
  .header-top { padding: 0 var(--space-sm); }
  .brand-full { font-size: 0.85rem; }
  .brand-sub { display: none; }
  .footer-links { gap: var(--space-md); }
  .footer-contact { flex-direction: column; gap: var(--space-sm); }
  .search-box[aria-hidden="false"] {
    position: absolute;
    top: calc(100% + 4px);
    left: var(--space-sm);
    right: var(--space-sm);
    max-width: none;
    background: var(--color-black);
    border: 1px solid var(--color-gold);
  }
  .search-input { color: var(--color-white); }
}

/* ===== UTILITY ===== */
.section-title { font-size: clamp(1.6rem, 4vw, 2.4rem); font-weight: 200; letter-spacing: 0.06em; color: var(--color-black); margin-bottom: var(--space-lg); }
.section-title strong { font-weight: 700; color: var(--color-primary); }
.container { max-width: var(--max-width); margin: 0 auto; padding: 0 var(--space-md); }
.text-gold { color: var(--color-gold); }
.text-primary { color: var(--color-primary); }
.bg-black { background: var(--color-black); }
.bg-primary { background: var(--color-primary); }

/* ===== PRINT ===== */
@media print {
  .nav-rail, .nav-toggle, .scroll-progress, .search-toggle, .search-box { display: none !important; }
  .header-top { margin-left: 0; background: #fff; color: #000; border-bottom: 1px solid #ccc; }
  .site-footer { margin-left: 0; }
  #main-content { margin-left: 0; }
  .skip-link { display: none; }
}