/* 深邃空气感科技风入口页背景（有机流体 + 色彩呼吸 + 鼠标视差） */
:root {
  --text: #1d1d1f;
  --sub: #5a6b7d;
  --accent: #4d6bfe;
  --accent-strong: #3b5cf0;
}

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

html, body { height: 100%; }

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  color: var(--text);
  height: 100vh;
  overflow: hidden;
  position: relative;
  display: flex;
  flex-direction: column;
  -webkit-font-smoothing: antialiased;
  /* Layer 0：径向渐变背景（中心纯白 → 浅灰蓝 → 边缘加深） */
  background: radial-gradient(ellipse at center, #ffffff 0%, #eef3f8 55%, #e2eaf2 100%);
}

/* 流体斑块层（视差容器） */
.parallax {
  position: absolute; inset: 0;
  z-index: 0; pointer-events: none;
  transition: transform 0.5s ease-out;
  will-change: transform;
}

/* Layer 1：网格（canvas，鼠标附近顶点随机波浪） */
#grid {
  position: absolute; inset: 0;
  z-index: 0; pointer-events: none;
  width: 100%; height: 100%;
  /* 向下渐隐：接近中线时网格缓慢消失 */
  -webkit-mask-image: linear-gradient(to bottom, #000 0%, #000 30%, transparent 50%);
  mask-image: linear-gradient(to bottom, #000 0%, #000 30%, transparent 50%);
}

/* Layer 2：流体斑块（深浅蓝色，有机流动 + 明暗呼吸） */
.blob {
  position: absolute; pointer-events: none;
  border-radius: 50%; filter: blur(45px);
  will-change: transform, opacity;
}
.blob-a {
  width: 620px; height: 620px; background: #8fb9e0;
  top: -150px; left: -150px;
  animation: organicA 24s ease-in-out infinite;
}
.blob-b {
  width: 420px; height: 420px; background: #aecbe4;
  top: 40%; left: 60%;
  animation: organicB 20s ease-in-out infinite;
}
.blob-c {
  width: 720px; height: 720px; background: #3f6a92;
  bottom: -200px; right: -200px;
  animation: organicC 28s ease-in-out infinite;
}
.blob-d {
  width: 520px; height: 520px; background: #5a97cf;
  bottom: 8%; left: -120px;
  animation: organicD 22s ease-in-out infinite;
}
.blob-e {
  width: 380px; height: 380px; background: #a5c9e9;
  top: 8%; right: 3%;
  animation: organicE 18s ease-in-out infinite;
}

/* 有机流动 + 色彩呼吸（opacity 明暗交替） */
@keyframes organicA {
  0%, 100% { transform: translate(0, 0) scale(1); opacity: 0.62; }
  25% { transform: translate(120px, 90px) scale(1.18); opacity: 0.85; }
  50% { transform: translate(-60px, 150px) scale(0.86); opacity: 0.52; }
  75% { transform: translate(60px, -45px) scale(1.1); opacity: 0.75; }
}
@keyframes organicB {
  0%, 100% { transform: translate(0, 0) scale(1); opacity: 0.66; }
  30% { transform: translate(-105px, -75px) scale(1.2); opacity: 0.88; }
  60% { transform: translate(75px, 60px) scale(0.85); opacity: 0.54; }
  85% { transform: translate(-45px, 45px) scale(1.08); opacity: 0.76; }
}
@keyframes organicC {
  0%, 100% { transform: translate(0, 0) scale(1); opacity: 0.58; }
  35% { transform: translate(90px, -105px) scale(1.15); opacity: 0.82; }
  65% { transform: translate(-75px, -45px) scale(0.88); opacity: 0.48; }
  90% { transform: translate(38px, 60px) scale(1.08); opacity: 0.7; }
}
@keyframes organicD {
  0%, 100% { transform: translate(0, 0) scale(1); opacity: 0.55; }
  40% { transform: translate(135px, 75px) scale(1.2); opacity: 0.8; }
  70% { transform: translate(-90px, -60px) scale(0.86); opacity: 0.46; }
}
@keyframes organicE {
  0%, 100% { transform: translate(0, 0) scale(1); opacity: 0.68; }
  30% { transform: translate(-75px, 60px) scale(1.14); opacity: 0.88; }
  60% { transform: translate(60px, -75px) scale(0.9); opacity: 0.58; }
  85% { transform: translate(-30px, -30px) scale(1.06); opacity: 0.78; }
}

/* Layer 3：内容层（绝对静止、清晰，保持在最上层） */
.top, .hero, .foot { position: relative; z-index: 1; }

.top {
  flex-shrink: 0;
  display: flex; align-items: center; justify-content: space-between;
  padding: 22px 32px;
}
.brand {
  color: var(--text); text-decoration: none;
  font-size: 18px; font-weight: 700; letter-spacing: 0.02em;
  transition: opacity .2s;
}
.brand:hover { opacity: 0.6; }

.hero {
  flex: 1;
  display: flex; flex-direction: column;
  align-items: center; justify-content: center;
  text-align: center; padding: 0 24px;
}
.hero h1 {
  font-size: 56px; font-weight: 700; letter-spacing: -0.03em;
  line-height: 1.15; margin-bottom: 20px;
}
.sub { font-size: 19px; color: var(--sub); margin-bottom: 48px; }

.actions { display: flex; gap: 16px; flex-wrap: wrap; justify-content: center; }
.btn {
  display: inline-block; text-decoration: none;
  font-size: 16px; font-weight: 500;
  padding: 14px 34px; border-radius: 12px;
  transition: transform .2s, background .2s, border-color .2s, box-shadow .2s;
}
/* 卡片悬浮：轻微上浮 + 投影变深 */
.btn:hover { transform: translateY(-3px); box-shadow: 0 12px 24px rgba(15, 23, 42, 0.14); }
.btn.primary { background: var(--accent); color: #fff; }
.btn.primary:hover { background: var(--accent-strong); box-shadow: 0 12px 28px rgba(77, 107, 254, 0.42); }
.btn.ghost {
  background: rgba(255, 255, 255, 0.5);
  color: var(--text);
  border: 1px solid rgba(0, 0, 0, 0.12);
}
.btn.ghost:hover {
  border-color: rgba(0, 0, 0, 0.28);
  background: rgba(255, 255, 255, 0.85);
  box-shadow: 0 12px 24px rgba(15, 23, 42, 0.1);
}

.foot {
  flex-shrink: 0;
  text-align: center; padding: 24px;
  font-size: 14px; color: var(--sub);
}
.foot a { color: var(--sub); text-decoration: none; border-bottom: 1px solid rgba(0, 0, 0, 0.2); }
.foot a:hover { color: var(--text); }

@media (max-width: 640px) {
  .hero h1 { font-size: 38px; }
  .sub { font-size: 16px; }
}