/* =====================================================
   THEME - 川三亨科技 赛博科技主题
   ===================================================== */

:root {
  /* 背景层 */
  --bg-base:     #0A0E1A;
  --bg-elevated: #0F1525;
  --bg-card:     rgba(20, 27, 45, 0.55);
  --bg-card-hi:  rgba(28, 38, 60, 0.7);

  /* 主色 */
  --cyan:   #00E5FF;
  --blue:   #3B82F6;
  --violet: #8B5CF6;
  --grad:   linear-gradient(135deg, #00E5FF 0%, #3B82F6 100%);
  --grad-v: linear-gradient(135deg, #3B82F6 0%, #8B5CF6 100%);

  /* 文本 */
  --text:      #E8EEF9;
  --text-soft: #9AA7C2;
  --text-mute: #5C6A8A;

  /* 线条/边框 */
  --line:        rgba(0, 229, 255, 0.18);
  --line-soft:   rgba(154, 167, 194, 0.12);
  --line-strong: rgba(0, 229, 255, 0.4);

  /* 阴影/光晕 */
  --glow-cyan: 0 0 24px rgba(0, 229, 255, 0.45);
  --glow-blue: 0 0 24px rgba(59, 130, 246, 0.45);
  --shadow-card: 0 8px 32px rgba(0, 0, 0, 0.4);

  /* 圆角 */
  --r-sm: 6px;
  --r-md: 12px;
  --r-lg: 18px;
  --r-xl: 28px;

  /* 字体 */
  --font-display: 'Orbitron', 'Noto Sans SC', 'PingFang SC', sans-serif;
  --font-body: 'Noto Sans SC', 'PingFang SC', 'HarmonyOS Sans', 'Microsoft YaHei', system-ui, sans-serif;
  --font-mono: 'JetBrains Mono', 'Cascadia Code', Consolas, monospace;
}

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

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

body {
  font-family: var(--font-body);
  background: var(--bg-base);
  color: var(--text);
  line-height: 1.7;
  font-size: 15px;
  overflow-x: hidden;
  position: relative;
  min-height: 100vh;
}

/* 背景层 - 渐变光斑 */
body::before {
  content: '';
  position: fixed;
  inset: 0;
  background:
    radial-gradient(circle at 15% 20%, rgba(0, 229, 255, 0.08), transparent 40%),
    radial-gradient(circle at 85% 80%, rgba(139, 92, 246, 0.07), transparent 45%),
    radial-gradient(circle at 50% 50%, rgba(59, 130, 246, 0.04), transparent 60%);
  pointer-events: none;
  z-index: 0;
}

a { color: inherit; text-decoration: none; transition: color .25s ease; }
a:hover { color: var(--cyan); }

img { max-width: 100%; height: auto; display: block; }
ul { list-style: none; }
button { font-family: inherit; cursor: pointer; border: none; background: none; color: inherit; }

/* ===== 通用容器 ===== */
.container {
  width: 100%;
  max-width: 1240px;
  margin: 0 auto;
  padding: 0 24px;
  position: relative;
  z-index: 2;
}

.main-content {
  position: relative;
  z-index: 2;
}

/* ===== 粒子背景 ===== */
.particles-canvas {
  position: fixed;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  opacity: 0.7;
}

/* 网格底纹 */
.grid-overlay {
  position: fixed;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  background-image:
    linear-gradient(rgba(0, 229, 255, 0.04) 1px, transparent 1px),
    linear-gradient(90deg, rgba(0, 229, 255, 0.04) 1px, transparent 1px);
  background-size: 60px 60px;
  mask-image: radial-gradient(circle at 50% 30%, black 0%, transparent 80%);
  -webkit-mask-image: radial-gradient(circle at 50% 30%, black 0%, transparent 80%);
}

/* 扫描线 */
.scanline {
  position: fixed;
  left: 0; right: 0;
  top: 0;
  height: 2px;
  background: linear-gradient(90deg, transparent, var(--cyan), transparent);
  z-index: 1;
  pointer-events: none;
  opacity: 0.4;
  animation: scan 8s linear infinite;
}
@keyframes scan {
  0%   { transform: translateY(0); opacity: 0; }
  10%  { opacity: 0.4; }
  90%  { opacity: 0.4; }
  100% { transform: translateY(100vh); opacity: 0; }
}

/* ===== 顶栏 ===== */
.topbar {
  background: rgba(10, 14, 26, 0.85);
  border-bottom: 1px solid var(--line-soft);
  font-size: 12px;
  color: var(--text-soft);
  font-family: var(--font-mono);
  letter-spacing: 0.5px;
  backdrop-filter: blur(8px);
  position: relative;
  z-index: 50;
}
.topbar-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-top: 8px;
  padding-bottom: 8px;
}
.topbar-left { display: flex; align-items: center; gap: 8px; }
.topbar-right { display: flex; gap: 20px; }

.dot-pulse {
  width: 8px; height: 8px; border-radius: 50%;
  background: var(--cyan);
  box-shadow: 0 0 10px var(--cyan);
  animation: pulse 1.6s ease-in-out infinite;
}
@keyframes pulse {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.4; transform: scale(0.85); }
}

/* ===== 导航 ===== */
.navbar {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(10, 14, 26, 0.75);
  backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--line);
  transition: all .3s ease;
}
.navbar.scrolled {
  background: rgba(10, 14, 26, 0.95);
  box-shadow: 0 4px 30px rgba(0, 0, 0, 0.5);
}
.navbar-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: 16px;
  padding-bottom: 16px;
  gap: 24px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  flex-shrink: 0;
}
.brand-mark { display: block; filter: drop-shadow(0 0 8px rgba(0, 229, 255, 0.5)); }
.brand-text { display: flex; flex-direction: column; line-height: 1.1; }
.brand-text strong {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 16px;
  letter-spacing: 1.5px;
  color: var(--text);
}
.brand-text small {
  font-family: var(--font-mono);
  font-size: 10px;
  color: var(--cyan);
  letter-spacing: 2px;
}

.nav-menu {
  display: flex;
  align-items: center;
  gap: 4px;
}
.nav-link {
  position: relative;
  padding: 10px 16px;
  font-size: 14px;
  color: var(--text-soft);
  font-weight: 500;
  border-radius: var(--r-sm);
  transition: all .25s ease;
}
.nav-link span { position: relative; z-index: 1; }
.nav-link::before {
  content: '';
  position: absolute;
  left: 50%; bottom: 4px;
  width: 0; height: 2px;
  background: var(--grad);
  transition: all .3s ease;
  transform: translateX(-50%);
}
.nav-link:hover { color: var(--text); }
.nav-link:hover::before { width: 60%; }
.nav-link.active { color: var(--cyan); }
.nav-link.active::before { width: 60%; box-shadow: var(--glow-cyan); }

.nav-cta { margin-left: 16px; }

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: 6px;
}
.nav-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--cyan);
  transition: all .3s ease;
  border-radius: 2px;
}
.nav-toggle.active span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav-toggle.active span:nth-child(2) { opacity: 0; }
.nav-toggle.active span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* ===== 按钮 ===== */
.btn-primary {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 24px;
  background: var(--grad);
  color: #0A0E1A;
  font-weight: 700;
  font-size: 14px;
  border-radius: var(--r-sm);
  letter-spacing: 0.5px;
  transition: all .3s ease;
  position: relative;
  overflow: hidden;
}
.btn-primary::before {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, transparent 30%, rgba(255,255,255,0.4) 50%, transparent 70%);
  transform: translateX(-100%);
  transition: transform .6s ease;
}
.btn-primary:hover {
  color: #0A0E1A;
  transform: translateY(-2px);
  box-shadow: var(--glow-cyan);
}
.btn-primary:hover::before { transform: translateX(100%); }

.btn-ghost {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 10px 20px;
  background: transparent;
  color: var(--cyan);
  border: 1px solid var(--line-strong);
  border-radius: var(--r-sm);
  font-weight: 500;
  font-size: 13px;
  letter-spacing: 0.5px;
  transition: all .3s ease;
}
.btn-ghost:hover {
  background: rgba(0, 229, 255, 0.08);
  border-color: var(--cyan);
  box-shadow: var(--glow-cyan);
  color: var(--cyan);
}
.btn-small { padding: 8px 16px; font-size: 12px; }

/* ===== 标题区 ===== */
.section {
  padding: 100px 0;
  position: relative;
}
.section-tight { padding: 64px 0; }

.section-head {
  text-align: center;
  margin-bottom: 56px;
  position: relative;
}
.section-eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 6px 14px;
  background: rgba(0, 229, 255, 0.08);
  border: 1px solid var(--line);
  border-radius: 100px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 2px;
  color: var(--cyan);
  text-transform: uppercase;
  margin-bottom: 18px;
}
.section-eyebrow::before {
  content: '';
  width: 6px; height: 6px; border-radius: 50%;
  background: var(--cyan);
  box-shadow: 0 0 8px var(--cyan);
}
.section-title {
  font-family: var(--font-display);
  font-size: clamp(28px, 4vw, 44px);
  font-weight: 700;
  letter-spacing: 1px;
  margin-bottom: 16px;
  background: linear-gradient(120deg, #fff 30%, var(--cyan) 100%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  line-height: 1.2;
}
.section-subtitle {
  font-size: 15px;
  color: var(--text-soft);
  max-width: 680px;
  margin: 0 auto;
  line-height: 1.8;
}

/* ===== 页脚 ===== */
.footer {
  background: linear-gradient(180deg, transparent, rgba(15, 21, 37, 0.7));
  border-top: 1px solid var(--line);
  padding-top: 64px;
  position: relative;
  z-index: 2;
  margin-top: 80px;
}
.footer-grid {
  display: grid;
  grid-template-columns: 1.5fr 1fr 1fr 1.2fr;
  gap: 40px;
  padding-bottom: 40px;
}
.footer-brand .brand { margin-bottom: 18px; }
.footer-slogan {
  color: var(--text-soft);
  font-size: 14px;
  line-height: 1.8;
  margin-bottom: 18px;
}
.footer-social { display: flex; gap: 10px; }
.social-ic {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 36px; height: 36px;
  border-radius: 50%;
  border: 1px solid var(--line);
  color: var(--text-soft);
  font-size: 16px;
  transition: all .3s ease;
}
.social-ic:hover {
  border-color: var(--cyan);
  color: var(--cyan);
  background: rgba(0, 229, 255, 0.06);
  box-shadow: var(--glow-cyan);
}
.footer-col h4 {
  font-family: var(--font-display);
  font-size: 14px;
  color: var(--text);
  margin-bottom: 18px;
  letter-spacing: 1.5px;
  position: relative;
  padding-left: 12px;
}
.footer-col h4::before {
  content: '';
  position: absolute;
  left: 0; top: 50%;
  width: 3px; height: 14px;
  background: var(--grad);
  transform: translateY(-50%);
  border-radius: 2px;
}
.footer-col ul li {
  margin-bottom: 10px;
  font-size: 13px;
  color: var(--text-soft);
}
.footer-col ul li a:hover { color: var(--cyan); padding-left: 4px; }
.footer-col ul li .ic {
  display: inline-block;
  width: 20px;
  color: var(--cyan);
}
.footer-contact .btn-ghost { margin-top: 12px; }

.footer-bottom {
  border-top: 1px solid var(--line-soft);
  padding: 18px 0;
  font-size: 12px;
  color: var(--text-mute);
  font-family: var(--font-mono);
}
.footer-bottom-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 10px;
}
.footer-links { display: flex; gap: 18px; }
.footer-links a:hover { color: var(--cyan); }
.admin-link { color: var(--text-mute); }
.admin-link:hover { color: var(--cyan); }

/* ===== 返回顶部 ===== */
.back-top {
  position: fixed;
  right: 24px; bottom: 24px;
  width: 44px; height: 44px;
  background: var(--bg-card);
  border: 1px solid var(--line);
  backdrop-filter: blur(8px);
  border-radius: 50%;
  color: var(--cyan);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 90;
  opacity: 0;
  transform: translateY(20px);
  pointer-events: none;
  transition: all .3s ease;
}
.back-top.show {
  opacity: 1;
  transform: translateY(0);
  pointer-events: auto;
}
.back-top:hover {
  border-color: var(--cyan);
  box-shadow: var(--glow-cyan);
  transform: translateY(-2px);
}