/* =====================================================
   Tech Theme v2 — 3D打印分享站
   深色科技风  主色 #38bdf8 / 青色 #22d3ee / 紫色 #a78bfa
   ===================================================== */

/* ---------- 设计令牌 ---------- */
:root {
  --bg:          #060d1f;
  --bg2:         #080f22;
  --surface:     #0d1730;
  --surface2:    #111e38;
  --muted:       #8899b4;
  --text:        #e8edf5;
  --text-dim:    #c0cce0;
  --brand:       #38bdf8;
  --brand-2:     #22d3ee;
  --accent:      #a78bfa;
  --accent-2:    #818cf8;
  --success:     #34d399;
  --warn:        #fbbf24;

  --brand-glow:  rgba(56,189,248,.40);
  --border:      rgba(148,163,184,.12);
  --border-hi:   rgba(56,189,248,.45);
  --shadow-sm:   0 4px 16px rgba(0,0,0,.45);
  --shadow:      0 10px 32px rgba(0,0,0,.60), 0 4px 12px rgba(2,132,199,.10);
  --shadow-lg:   0 20px 60px rgba(0,0,0,.70), 0 8px 24px rgba(2,132,199,.16);

  --radius-sm:   8px;
  --radius:      14px;
  --radius-lg:   20px;

  --ease-out-expo: cubic-bezier(0.16,1,0.3,1);
  --ease-spring:   cubic-bezier(0.34,1.56,0.64,1);
}

/* ---------- Reset ---------- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; -webkit-font-smoothing: antialiased; }
body {
  font-family: "Inter","Noto Sans SC",system-ui,-apple-system,"Segoe UI",Roboto,
    "PingFang SC","Hiragino Sans GB","Microsoft YaHei",sans-serif;
  line-height: 1.7;
  color: var(--text);
  background: var(--bg);
  overflow-x: hidden;
}
img { max-width: 100%; display: block; }
a { color: var(--brand); text-decoration: none; }
a:hover { color: var(--brand-2); }
ul, ol { list-style: none; }
button { cursor: pointer; font-family: inherit; }

/* ---------- 容器 ---------- */
.container {
  max-width: 1180px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ---------- 滚动入场动画基类 ---------- */
[data-anim] {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity .7s var(--ease-out-expo), transform .7s var(--ease-out-expo);
}
[data-anim].in-view {
  opacity: 1;
  transform: none;
}
[data-anim="fade-left"]  { transform: translateX(-40px); }
[data-anim="fade-right"] { transform: translateX(40px); }
[data-anim="scale"]      { transform: scale(.92); }
[data-anim="fade-left"].in-view,
[data-anim="fade-right"].in-view,
[data-anim="scale"].in-view { transform: none; opacity: 1; }

/* 延迟 */
[data-delay="1"] { transition-delay: .10s; }
[data-delay="2"] { transition-delay: .20s; }
[data-delay="3"] { transition-delay: .30s; }
[data-delay="4"] { transition-delay: .40s; }
[data-delay="5"] { transition-delay: .50s; }
[data-delay="6"] { transition-delay: .60s; }

/* ---------- 顶部导航 ---------- */
.site-header {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 200;
  transition: background .4s, border-color .4s, box-shadow .4s;
}
.site-header.scrolled {
  background: rgba(6,13,31,.85);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--border);
  box-shadow: 0 2px 20px rgba(0,0,0,.4);
}
.site-nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 18px 0;
  transition: padding .4s;
}
.site-header.scrolled .site-nav { padding: 12px 0; }

.site-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  font-size: 17px;
  color: var(--text);
  letter-spacing: .3px;
}
.site-logo img { height: 34px; border-radius: 8px; }
.site-logo .logo-text { background: linear-gradient(90deg, var(--brand), var(--brand-2)); -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text; }
.site-logo:hover { color: var(--text); }

.nav-links {
  display: flex;
  align-items: center;
  gap: 4px;
}
.nav-links a {
  padding: 8px 16px;
  border-radius: var(--radius-sm);
  color: var(--muted);
  font-size: 14px;
  font-weight: 500;
  border: 1px solid transparent;
  transition: color .2s, background .2s, border-color .2s;
  position: relative;
}
.nav-links a::after {
  content: '';
  position: absolute;
  bottom: 4px; left: 50%; right: 50%;
  height: 2px;
  background: linear-gradient(90deg, var(--brand), var(--brand-2));
  border-radius: 2px;
  transition: left .3s var(--ease-out-expo), right .3s var(--ease-out-expo);
}
.nav-links a:hover { color: var(--text); background: rgba(56,189,248,.07); }
.nav-links a:hover::after { left: 16px; right: 16px; }
.nav-links a.active { color: var(--brand); }
.nav-links a.active::after { left: 16px; right: 16px; }

/* ---------- 渐变分割线 ---------- */
.gradient-line {
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--border-hi), transparent);
  margin: 60px 0;
}

/* ---------- 节标题 ---------- */
.section-label {
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 2px;
  text-transform: uppercase;
  color: var(--brand);
  margin-bottom: 10px;
}
.section-title {
  font-size: 34px;
  font-weight: 800;
  color: var(--text);
  line-height: 1.25;
  margin-bottom: 10px;
}
.section-title span {
  background: linear-gradient(90deg, var(--brand), var(--brand-2));
  -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text;
}
.section-sub {
  font-size: 15px;
  color: var(--muted);
  line-height: 1.7;
  max-width: 580px;
}

/* ---------- 卡片 ---------- */
.card {
  background: linear-gradient(145deg, var(--surface), var(--surface2));
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  box-shadow: var(--shadow);
  transition: transform .3s var(--ease-out-expo), box-shadow .3s, border-color .3s;
}
.card:hover {
  transform: translateY(-5px);
  border-color: rgba(56,189,248,.30);
  box-shadow: var(--shadow-lg);
}

/* ---------- 徽章/标签 ---------- */
.badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 12px;
  border-radius: 99px;
  font-size: 11px;
  font-weight: 700;
  letter-spacing: .5px;
  text-transform: uppercase;
  background: rgba(56,189,248,.10);
  color: var(--brand);
  border: 1px solid rgba(56,189,248,.22);
}
.badge-accent {
  background: rgba(167,139,250,.10);
  color: var(--accent);
  border-color: rgba(167,139,250,.22);
}
.badge-success {
  background: rgba(52,211,153,.10);
  color: var(--success);
  border-color: rgba(52,211,153,.22);
}

/* ---------- 主按钮 ---------- */
.btn-primary {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 26px;
  border-radius: var(--radius-sm);
  font-size: 14px;
  font-weight: 700;
  background: linear-gradient(135deg, var(--brand), var(--brand-2));
  color: #03111f;
  border: none;
  box-shadow: 0 6px 22px rgba(56,189,248,.30);
  transition: transform .2s var(--ease-spring), box-shadow .2s;
  letter-spacing: .2px;
}
.btn-primary:hover {
  transform: translateY(-2px) scale(1.02);
  box-shadow: 0 10px 32px rgba(56,189,248,.50);
  color: #03111f;
}
.btn-ghost {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 11px 24px;
  border-radius: var(--radius-sm);
  font-size: 14px;
  font-weight: 600;
  background: transparent;
  color: var(--text-dim);
  border: 1px solid var(--border);
  transition: border-color .2s, color .2s, background .2s;
}
.btn-ghost:hover {
  border-color: var(--border-hi);
  color: var(--brand);
  background: rgba(56,189,248,.06);
}

/* ---------- 公告条 ---------- */
.notice-bar {
  padding: 10px 16px;
  border: 1px solid rgba(56,189,248,.15);
  border-radius: 10px;
  background: rgba(56,189,248,.04);
  color: var(--muted);
  font-size: 12.5px;
  line-height: 1.8;
}
.notice-bar p { margin: 0; }

/* ---------- 页脚 ---------- */
.site-footer {
  border-top: 1px solid var(--border);
  padding: 32px 0 40px;
  color: var(--muted);
  font-size: 13px;
  margin-top: 80px;
}
.site-footer .inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
}
.site-footer .beian {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 10px;
}
.site-footer .beian a { color: var(--muted); transition: color .2s; }
.site-footer .beian a:hover { color: var(--brand); }
.site-footer .beian img { width: 16px; height: 16px; border-radius: 3px; }

/* ---------- 响应式 ---------- */
@media (max-width: 768px) {
  .nav-links { display: none; }
  .section-title { font-size: 26px; }
}
@media (max-width: 480px) {
  .site-logo .logo-text { display: none; }
  .container { padding: 0 16px; }
}