:root {
  --bg: #05060c;
  --bg-2: #0a0e1a;
  --panel: rgba(255, 255, 255, 0.04);
  --panel-border: rgba(120, 180, 255, 0.14);
  --text: #e8eefc;
  --muted: #8a96b4;
  --cyan: #4fd6ff;
  --blue: #5b8cff;
  --orange: #ff8a4c;
  --grad: linear-gradient(100deg, #4fd6ff 0%, #5b8cff 45%, #ff8a4c 100%);
  --maxw: 1120px;
}

* { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: smooth; }

body {
  font-family: "Segoe UI", "PingFang SC", "Microsoft YaHei", system-ui, sans-serif;
  background: radial-gradient(1200px 800px at 70% -10%, #16213f 0%, var(--bg) 55%) fixed;
  color: var(--text);
  line-height: 1.65;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

#plasma {
  position: fixed;
  inset: 0;
  z-index: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  opacity: 0.55;
}

/* 内容层级在画布之上 */
.nav, main, .footer { position: relative; z-index: 1; }

.grad {
  background: var(--grad);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.eyebrow {
  display: inline-block;
  font-size: 0.78rem;
  letter-spacing: 0.28em;
  text-transform: uppercase;
  color: var(--cyan);
  margin-bottom: 1rem;
  font-weight: 600;
}

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.8rem 1.5rem;
  border-radius: 999px;
  font-size: 0.95rem;
  font-weight: 600;
  text-decoration: none;
  cursor: pointer;
  border: 1px solid transparent;
  transition: transform 0.2s ease, box-shadow 0.3s ease, background 0.3s ease;
}
.btn-primary {
  background: var(--grad);
  color: #04101e;
  box-shadow: 0 8px 30px rgba(79, 214, 255, 0.28);
}
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 12px 40px rgba(91, 140, 255, 0.45); }
.btn-ghost {
  background: rgba(255, 255, 255, 0.03);
  border-color: var(--panel-border);
  color: var(--text);
  backdrop-filter: blur(8px);
}
.btn-ghost:hover { border-color: var(--cyan); transform: translateY(-2px); }

/* ---------- 导航 ---------- */
.nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem 2rem;
  backdrop-filter: blur(12px);
  background: rgba(5, 6, 12, 0.5);
  border-bottom: 1px solid transparent;
  transition: background 0.3s ease, border-color 0.3s ease;
}
.nav.scrolled {
  background: rgba(5, 6, 12, 0.82);
  border-bottom: 1px solid var(--panel-border);
}
.brand {
  font-weight: 800;
  letter-spacing: 0.16em;
  font-size: 1.1rem;
  color: var(--text);
  text-decoration: none;
}
.brand-mark {
  color: var(--cyan);
  text-shadow: 0 0 14px var(--cyan);
  margin-right: 0.35rem;
}
.nav-links { display: flex; gap: 1.8rem; }
.nav-links a {
  color: var(--muted);
  text-decoration: none;
  font-size: 0.92rem;
  transition: color 0.2s ease;
}
.nav-links a:hover { color: var(--text); }
.nav-cta { padding: 0.5rem 1.1rem; font-size: 0.85rem; }

/* ---------- HERO ---------- */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 8rem 1.5rem 4rem;
}
.hero-inner { max-width: 880px; }
.hero-title {
  font-size: clamp(2.8rem, 8vw, 5.5rem);
  line-height: 1.05;
  font-weight: 800;
  letter-spacing: -0.02em;
  margin-bottom: 1.5rem;
}
.hero-sub {
  font-size: clamp(1rem, 2.2vw, 1.25rem);
  color: var(--muted);
  max-width: 640px;
  margin: 0 auto 2.2rem;
}
.hero-actions { display: flex; gap: 1rem; justify-content: center; flex-wrap: wrap; }

.metrics {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1rem;
  margin-top: 4rem;
  padding-top: 2.5rem;
  border-top: 1px solid var(--panel-border);
}
.metric-val {
  font-size: clamp(1.5rem, 4vw, 2.4rem);
  font-weight: 800;
  background: var(--grad);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}
.metric-label { font-size: 0.82rem; color: var(--muted); margin-top: 0.3rem; }

/* ---------- 通用 section ---------- */
.section {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 6rem 1.5rem;
}
.section-head { max-width: 720px; margin-bottom: 3rem; }
.section-head h2 {
  font-size: clamp(1.8rem, 5vw, 3rem);
  font-weight: 800;
  letter-spacing: -0.01em;
  margin-bottom: 1rem;
}
.section-head p { color: var(--muted); font-size: 1.05rem; }

/* ---------- 概念卡片 ---------- */
.concept-grid, .feature-list, .steps, .timeline {
  display: grid;
  gap: 1.4rem;
}
.concept-grid { grid-template-columns: repeat(3, 1fr); }
.card {
  background: var(--panel);
  border: 1px solid var(--panel-border);
  border-radius: 18px;
  padding: 2rem 1.6rem;
  backdrop-filter: blur(10px);
  transition: transform 0.3s ease, border-color 0.3s ease, box-shadow 0.3s ease;
}
.card:hover {
  transform: translateY(-6px);
  border-color: rgba(79, 214, 255, 0.4);
  box-shadow: 0 18px 50px rgba(79, 214, 255, 0.12);
}
.card-icon { font-size: 2rem; margin-bottom: 1rem; }
.card h3 { font-size: 1.2rem; margin-bottom: 0.6rem; }
.card p { color: var(--muted); font-size: 0.95rem; }

/* ---------- 特性列表 ---------- */
.feature-list { grid-template-columns: repeat(2, 1fr); }
.feature {
  display: flex;
  gap: 1.2rem;
  align-items: flex-start;
  background: var(--panel);
  border: 1px solid var(--panel-border);
  border-radius: 16px;
  padding: 1.6rem;
  backdrop-filter: blur(10px);
  transition: border-color 0.3s ease, transform 0.3s ease;
}
.feature:hover { border-color: rgba(91, 140, 255, 0.4); transform: translateY(-4px); }
.feature-no {
  font-size: 1.4rem;
  font-weight: 800;
  color: transparent;
  background: var(--grad);
  -webkit-background-clip: text;
  background-clip: text;
  flex-shrink: 0;
}
.feature h3 { font-size: 1.1rem; margin-bottom: 0.4rem; }
.feature p { color: var(--muted); font-size: 0.95rem; }

/* ---------- 步骤 ---------- */
.steps { grid-template-columns: repeat(4, 1fr); }
.step {
  position: relative;
  background: var(--panel);
  border: 1px solid var(--panel-border);
  border-radius: 16px;
  padding: 2rem 1.4rem 1.6rem;
  backdrop-filter: blur(10px);
}
.step-num {
  width: 44px; height: 44px;
  display: grid; place-items: center;
  border-radius: 50%;
  background: var(--grad);
  color: #04101e;
  font-weight: 800;
  margin-bottom: 1rem;
  box-shadow: 0 6px 20px rgba(79, 214, 255, 0.3);
}
.step h3 { font-size: 1.1rem; margin-bottom: 0.5rem; }
.step p { color: var(--muted); font-size: 0.92rem; }

/* ---------- 时间线 ---------- */
.timeline { grid-template-columns: repeat(4, 1fr); }
.tl-item {
  border-left: 2px solid var(--panel-border);
  padding-left: 1.2rem;
  position: relative;
}
.tl-item::before {
  content: "";
  position: absolute;
  left: -7px; top: 4px;
  width: 12px; height: 12px;
  border-radius: 50%;
  background: var(--grad);
  box-shadow: 0 0 12px rgba(79, 214, 255, 0.6);
}
.tl-year {
  font-size: 1.6rem;
  font-weight: 800;
  color: transparent;
  background: var(--grad);
  -webkit-background-clip: text;
  background-clip: text;
}
.tl-item h3 { font-size: 1.05rem; margin: 0.4rem 0; }
.tl-item p { color: var(--muted); font-size: 0.9rem; }

/* ---------- 愿景 ---------- */
.vision { text-align: center; }
.vision-inner { max-width: 760px; margin: 0 auto; }
.vision h2 { font-size: clamp(2rem, 6vw, 3.4rem); font-weight: 800; margin-bottom: 1.2rem; }
.vision p { color: var(--muted); font-size: 1.15rem; }

/* ---------- CTA ---------- */
.cta-card {
  background: linear-gradient(135deg, rgba(79, 214, 255, 0.1), rgba(255, 138, 76, 0.08));
  border: 1px solid var(--panel-border);
  border-radius: 24px;
  padding: 3.5rem 2rem;
  text-align: center;
  backdrop-filter: blur(12px);
}
.cta-card h2 { font-size: clamp(1.6rem, 4vw, 2.4rem); margin-bottom: 0.8rem; }
.cta-card p { color: var(--muted); margin-bottom: 2rem; }
.cta-form { display: flex; gap: 0.6rem; justify-content: center; flex-wrap: wrap; }
.cta-form input {
  padding: 0.8rem 1.2rem;
  border-radius: 999px;
  border: 1px solid var(--panel-border);
  background: rgba(255, 255, 255, 0.05);
  color: var(--text);
  font-size: 0.95rem;
  min-width: 260px;
  outline: none;
}
.cta-form input:focus { border-color: var(--cyan); }

/* ---------- 页脚 ---------- */
.footer {
  border-top: 1px solid var(--panel-border);
  padding: 2.5rem 1.5rem;
  text-align: center;
  color: var(--muted);
}
.footer-brand { font-weight: 800; letter-spacing: 0.16em; color: var(--text); margin-bottom: 0.5rem; }
.footer p { font-size: 0.85rem; }

/* ---------- 滚动揭示动画 ---------- */
.reveal {
  opacity: 0;
  transform: translateY(28px);
  transition: opacity 0.7s cubic-bezier(0.2, 0.7, 0.2, 1), transform 0.7s cubic-bezier(0.2, 0.7, 0.2, 1);
}
.reveal.visible { opacity: 1; transform: none; }

/* ---------- 响应式 ---------- */
@media (max-width: 900px) {
  .nav-links { display: none; }
  .concept-grid, .feature-list, .steps, .timeline { grid-template-columns: 1fr; }
  .metrics { grid-template-columns: repeat(2, 1fr); row-gap: 2rem; }
}
@media (max-width: 520px) {
  .nav { padding: 0.9rem 1.2rem; }
  .nav-cta { display: none; }
  .section { padding: 4rem 1.2rem; }
}

/* 尊重减少动画偏好 */
@media (prefers-reduced-motion: reduce) {
  .reveal { opacity: 1; transform: none; transition: none; }
  html { scroll-behavior: auto; }
}