/* 全局与主题 */
:root {
  --bg-start: #0b1022;
  --bg-end: #121a36;
  --text: #e5e7eb;
  --muted: #a1a9c6;
  --card-bg: rgba(255, 255, 255, 0.06);
  --card-border: rgba(255, 255, 255, 0.14);
  --accent: #60a5fa;
}

* { box-sizing: border-box; }
html, body { height: 100%; }
body {
  margin: 0;
  color: var(--text);
  font: 16px/1.6 ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans", "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", "WenQuanYi Micro Hei", sans-serif;
  background: linear-gradient(120deg, var(--bg-start), var(--bg-end));
}

/* 顶栏 */
.topbar {
  position: sticky;
  top: 0;
  z-index: 1000;
  height: 60px;
  display: flex;
  align-items: center;
  justify-content: center; /* 居中，仅显示一个导航项 */
  background: rgba(10, 15, 35, 0.6);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid rgba(255, 255, 255, 0.06);
}
.nav-link {
  color: var(--text);
  text-decoration: none;
  padding: 8px 14px;
  border-radius: 8px;
  transition: all .25s ease;
  border: 1px solid transparent;
}
.nav-link:hover {
  border-color: rgba(255, 255, 255, 0.14);
  background: rgba(255, 255, 255, 0.06);
}

/* 英雄区域（大标题） */
.hero {
  min-height: 86vh;
  padding: 96px 24px 48px;
  display: grid;
  place-items: center;
  text-align: center;
  position: relative;
  overflow: hidden;
}
.hero::before, .hero::after {
  content: "";
  position: absolute;
  inset: -20% -10%;
  filter: blur(80px);
  opacity: .35;
  pointer-events: none;
}
.hero::before {
  background:
    radial-gradient(600px 320px at 20% 30%, #8b5cf6 20%, transparent 60%),
    radial-gradient(480px 280px at 85% 20%, #22d3ee 20%, transparent 60%);
  animation: floatBg 18s ease-in-out infinite;
}
.hero::after {
  background:
    radial-gradient(560px 300px at 50% 85%, #f43f5e 20%, transparent 60%),
    radial-gradient(520px 280px at 10% 80%, #f59e0b 20%, transparent 60%);
  animation: floatBg2 22s ease-in-out infinite;
}

/* .brand 大标题：慢速颜色律动（无模糊、无缩放） */
.brand {
  margin: 0;
  font-weight: 800;
  letter-spacing: 2px;
  font-size: clamp(48px, 12vw, 160px);
  background: linear-gradient(135deg,
    #ff6b6b 0%,
    #f7b267 12%,
    #fbd786 24%,
    #a8e6cf 36%,
    #84fab0 48%,
    #60a5fa 60%,
    #a78bfa 72%,
    #f472b6 84%,
    #ff6b6b 100%);
  background-size: 320% 320%;
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  /* 仅保留颜色慢速律动，不使用任何滤镜 */
  animation: gradientFlow 14s ease-in-out infinite;
  /* 轻微光晕但不影响清晰度 */
  text-shadow:
    0 0 10px rgba(99,102,241,.18),
    0 0 22px rgba(99,102,241,.12);
  /* 提升文字渲染清晰度（不同浏览器效果不一） */
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
  will-change: background-position;
}
.tagline {
  margin-top: 18px;
  color: var(--muted);
  font-size: 16px;
}

.hero-actions {
  margin-top: 28px;
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  justify-content: center;
}
.cta {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 12px 18px;
  border-radius: 12px;
  color: #0b1022;
  text-decoration: none;
  font-weight: 600;
  background: linear-gradient(135deg, #f0abfc, #60a5fa);
  box-shadow: 0 12px 28px rgba(96, 165, 250, 0.25);
  transition: transform .2s ease, box-shadow .2s ease;
}
.cta:hover {
  transform: translateY(-2px);
  box-shadow: 0 16px 36px rgba(96, 165, 250, 0.35);
}

.scroll-indicator {
  position: absolute;
  bottom: 20px;
  left: 50%;
  transform: translateX(-50%);
  color: var(--muted);
  font-size: 13px;
  letter-spacing: 1px;
  opacity: .8;
}

/* 内容卡片区域 */
.sections {
  padding: 28px 20px 64px;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 18px;
  max-width: 1100px;
  margin: 0 auto;
}
.card {
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  padding: 22px;
  border-radius: 16px;
  backdrop-filter: blur(8px);
  box-shadow: 0 12px 32px rgba(0,0,0,0.25);
  transition: transform .24s ease, box-shadow .24s ease, border-color .24s ease;
  will-change: transform;
}
.card:hover {
  transform: translateY(-6px);
  box-shadow: 0 18px 42px rgba(0,0,0,0.32);
  border-color: rgba(255, 255, 255, 0.22);
}
.card h3 {
  margin: 0 0 8px 0;
  font-size: 20px;
}
.card p {
  margin: 0 0 14px 0;
  color: var(--muted);
}
.card-link {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 10px 14px;
  border-radius: 12px;
  text-decoration: none;
  color: var(--text);
  border: 1px dashed rgba(255,255,255,0.35);
  transition: all .22s ease;
}
.card-link:hover {
  background: rgba(255,255,255,0.08);
  border-style: solid;
}

/* 关于拥有者区域 */
.about {
  max-width: 860px;
  margin: 12px auto 72px;
  padding: 0 20px;
}
.about h2 {
  margin: 24px 0 6px;
  font-size: 24px;
}
.about p {
  margin: 0;
  color: var(--muted);
}

/* 页脚 */
.footer {
  border-top: 1px solid rgba(255,255,255,0.08);
  padding: 24px 20px 36px;
  text-align: center;
  color: var(--muted);
}
.footer a {
  color: var(--text);
  text-decoration: none;
  border-bottom: 1px dashed rgba(255,255,255,0.25);
}
.footer a:hover {
  border-bottom-style: solid;
}

/* 动画 */
@keyframes gradientFlow {
  0%   { background-position: 0% 50%; }
  50%  { background-position: 100% 50%; }
  100% { background-position: 0% 50%; }
}
@keyframes beatPulse {
  0%, 100% {
    transform: scale(1);
    text-shadow:
      0 0 14px rgba(255,255,255,.06),
      0 0 26px rgba(99,102,241,.32),
      0 0 52px rgba(99,102,241,.24);
  }
  50% {
    transform: scale(1.06);
    text-shadow:
      0 0 18px rgba(255,255,255,.10),
      0 0 36px rgba(99,102,241,.44),
      0 0 72px rgba(99,102,241,.32);
  }
}
@keyframes hueShift {
  0%   { filter: blur(0.8px) saturate(115%) hue-rotate(0deg); }
  100% { filter: blur(0.8px) saturate(115%) hue-rotate(360deg); }
}
@keyframes floatBg {
  0%, 100% { transform: translate3d(0,0,0); }
  50% { transform: translate3d(2%, -3%, 0); }
}
@keyframes floatBg2 {
  0%, 100% { transform: translate3d(0,0,0); }
  50% { transform: translate3d(-3%, 2%, 0); }
}

/* 自适应与低动态偏好 */
@media (max-width: 640px) {
  .hero { padding-top: 88px; }
  .brand { letter-spacing: 1px; }
}
@media (prefers-reduced-motion: reduce) {
  .brand, .hero::before, .hero::after { animation: none !important; }
  .card { transition: none; }
}