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

:root {
  --bg: #05060a;
  --fg: #e8ecf5;
  --fg-dim: #8a93a8;
  --cyan: #00f0ff;
  --violet: #7c3aed;
  --pink: #ff3d9a;
  --ease: cubic-bezier(0.16, 1, 0.3, 1);
}

html { scroll-behavior: smooth; }

body {
  background: var(--bg);
  color: var(--fg);
  font-family: 'Space Grotesk', -apple-system, BlinkMacSystemFont, sans-serif;
  overflow-x: hidden;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

/* ===== 3D 背景画布 ===== */
#bg-canvas {
  position: fixed;
  inset: 0;
  width: 100vw;
  height: 100vh;
  z-index: 0;
  display: block;
}

/* 背景渐晕,增强深度 */
body::before {
  content: '';
  position: fixed;
  inset: 0;
  z-index: 1;
  pointer-events: none;
  background:
    radial-gradient(ellipse 80% 50% at 50% 0%, rgba(124, 58, 237, 0.12), transparent 60%),
    radial-gradient(ellipse 60% 50% at 50% 100%, rgba(0, 240, 255, 0.08), transparent 60%);
}

/* ===== 鼠标光晕 ===== */
#cursor-glow {
  position: fixed;
  width: 600px;
  height: 600px;
  left: 0; top: 0;
  margin: -300px 0 0 -300px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(0, 240, 255, 0.06), transparent 60%);
  pointer-events: none;
  z-index: 2;
  transform: translate3d(50vw, 50vh, 0);
  transition: transform 0.6s var(--ease);
  mix-blend-mode: screen;
}

/* ===== 滚动进度条 ===== */
#scroll-progress {
  position: fixed;
  top: 0; left: 0;
  height: 2px;
  width: 0%;
  background: linear-gradient(90deg, var(--cyan), var(--violet), var(--pink));
  z-index: 100;
  box-shadow: 0 0 12px var(--cyan);
}

/* ===== 导航 ===== */
#nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 50;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 28px 5vw;
  font-size: 14px;
  letter-spacing: 0.15em;
}

.nav-logo {
  font-family: 'Syncopate', sans-serif;
  font-weight: 700;
  font-size: 15px;
}

.nav-links { display: flex; gap: 36px; }
.nav-links a {
  color: var(--fg-dim);
  text-decoration: none;
  font-size: 12px;
  font-weight: 500;
  transition: color 0.4s var(--ease);
}
.nav-links a:hover { color: var(--cyan); }

/* ===== 主内容 ===== */
main { position: relative; z-index: 10; }

.section {
  min-height: 100vh;
  display: flex;
  align-items: center;
  padding: 0 8vw;
  position: relative;
}

/* ===== Hero ===== */
.section-hero { justify-content: flex-start; text-align: left; }

.hero-inner { max-width: 720px; }

.hero-title {
  font-family: 'Syncopate', sans-serif;
  font-weight: 700;
  font-size: clamp(48px, 9vw, 120px);
  line-height: 0.95;
  letter-spacing: 0.02em;
  background: linear-gradient(135deg, #fff 0%, var(--cyan) 45%, var(--violet) 100%);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  margin-bottom: 32px;
  overflow-wrap: break-word;
}

.hero-sub {
  font-size: clamp(16px, 2.4vw, 26px);
  font-weight: 300;
  color: var(--fg-dim);
  max-width: 480px;
  margin: 0 0 64px;
  letter-spacing: 0.04em;
}

.scroll-hint {
  display: inline-flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
  font-size: 11px;
  letter-spacing: 0.3em;
  color: var(--fg-dim);
}
.scroll-line {
  width: 1px; height: 50px;
  background: linear-gradient(var(--cyan), transparent);
  animation: scrollPulse 2s var(--ease) infinite;
}
@keyframes scrollPulse {
  0%, 100% { transform: scaleY(0.4); transform-origin: top; opacity: 0.4; }
  50% { transform: scaleY(1); opacity: 1; }
}

/* ===== 叙事区 ===== */
.section-content { max-width: 640px; position: relative; }
.section-content-right { margin-left: auto; }
.section-content-center { margin: 0 auto; text-align: center; }

.section-index {
  display: block;
  font-family: 'Syncopate', sans-serif;
  font-size: 13px;
  letter-spacing: 0.3em;
  color: var(--cyan);
  margin-bottom: 24px;
  opacity: 0.7;
}

.section-content h2 {
  font-family: 'Space Grotesk', sans-serif;
  font-weight: 700;
  font-size: clamp(34px, 6vw, 76px);
  line-height: 1.05;
  margin-bottom: 28px;
  letter-spacing: -0.02em;
}

.section-content p {
  font-size: clamp(16px, 2vw, 21px);
  font-weight: 300;
  color: var(--fg-dim);
  max-width: 480px;
}

.section-content-center p { margin: 0 auto 40px; }

.cta {
  display: inline-block;
  padding: 16px 40px;
  border: 1px solid rgba(0, 240, 255, 0.4);
  border-radius: 999px;
  color: var(--cyan);
  text-decoration: none;
  font-size: 14px;
  letter-spacing: 0.15em;
  font-weight: 500;
  transition: all 0.5s var(--ease);
  backdrop-filter: blur(6px);
}
.cta:hover {
  background: rgba(0, 240, 255, 0.1);
  border-color: var(--cyan);
  box-shadow: 0 0 30px rgba(0, 240, 255, 0.3);
  transform: translateY(-2px);
}

/* ===== 文案浮现动画 ===== */
.reveal {
  opacity: 0;
  transform: translateY(40px);
  transition: opacity 1s var(--ease), transform 1s var(--ease);
}
.reveal.is-visible {
  opacity: 1;
  transform: translateY(0);
}
.reveal[data-delay="1"] { transition-delay: 0.15s; }
.reveal[data-delay="2"] { transition-delay: 0.3s; }

/* ===== Footer ===== */
footer {
  position: relative;
  z-index: 10;
  display: flex;
  justify-content: space-between;
  padding: 40px 5vw;
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--fg-dim);
  border-top: 1px solid rgba(255, 255, 255, 0.05);
}

/* ===== 响应式 ===== */
@media (max-width: 768px) {
  #nav { padding: 20px 6vw; }
  .nav-links { gap: 20px; }
  .section { padding: 0 8vw; }
  .section-content { max-width: 100%; }
  .section-content-right { margin-left: 0; }
  /* 移动端:3D 物体居中偏后,文字居中、加透明度保证可读 */
  .section-hero { justify-content: center; text-align: center; padding-top: 30vh; }
  .hero-sub { margin: 0 auto 48px; }
  .section-content-center { text-align: center; }
  footer { flex-direction: column; gap: 8px; text-align: center; }
}

/* ===== 减少动效偏好 ===== */
@media (prefers-reduced-motion: reduce) {
  .reveal { opacity: 1; transform: none; transition: none; }
  .scroll-line { animation: none; }
  html { scroll-behavior: auto; }
}