/* ===== 超级计划 产品介绍页 ===== */
:root {
  --primary: #4A90D9;
  --primary-dark: #3A78B9;
  --accent: #7C5CE0;
  --bg: #ffffff;
  --bg-alt: #f6f8fb;
  --text: #1f2733;
  --text-secondary: #5c6b7f;
  --border: #e6ebf2;
  --radius: 14px;
  --shadow: 0 8px 30px rgba(31, 39, 51, 0.08);
  --shadow-hover: 0 14px 40px rgba(31, 39, 51, 0.14);
  --nav-h: 64px;
}

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

html { scroll-behavior: smooth; }

body {
  font-family: "Microsoft YaHei", "PingFang SC", "Segoe UI", system-ui, -apple-system, sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

a { text-decoration: none; color: inherit; }
ul { list-style: none; }
kbd {
  display: inline-block;
  padding: 1px 7px;
  margin: 0 2px;
  font-size: 13px;
  font-family: inherit;
  background: #eef2f7;
  border: 1px solid #d5dde8;
  border-bottom-width: 2px;
  border-radius: 5px;
  color: var(--text);
}

/* ===== 按钮 ===== */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 10px 22px;
  border-radius: 10px;
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
  transition: transform .15s ease, box-shadow .2s ease, background .2s ease, color .2s ease;
  border: none;
}
.btn-lg { padding: 13px 28px; font-size: 16px; border-radius: 12px; }
.btn-xl { padding: 16px 36px; font-size: 17px; border-radius: 12px; }
.btn-primary {
  background: linear-gradient(135deg, var(--primary), var(--accent));
  color: #fff;
  box-shadow: 0 8px 24px rgba(74, 144, 217, 0.35);
}
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 12px 32px rgba(74, 144, 217, 0.45); }
.btn-ghost {
  background: rgba(255, 255, 255, 0.08);
  color: #fff;
  border: 1px solid rgba(255, 255, 255, 0.35);
  backdrop-filter: blur(4px);
}
.btn-ghost:hover { background: rgba(255, 255, 255, 0.16); transform: translateY(-2px); }
.btn-ico { font-size: 16px; }

/* ===== 导航栏 ===== */
.nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  height: var(--nav-h);
  z-index: 100;
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
}
.nav-inner {
  max-width: 1100px;
  margin: 0 auto;
  height: 100%;
  padding: 0 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.brand { display: flex; align-items: center; gap: 8px; font-size: 18px; font-weight: 700; }
.brand-mark {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 26px; height: 26px;
  border-radius: 8px;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  color: #fff;
  font-size: 14px;
  font-weight: 700;
}
.nav-links { display: flex; gap: 26px; }
.nav-links a { font-size: 15px; color: var(--text-secondary); transition: color .2s; }
.nav-links a:hover { color: var(--primary); }
.nav-download { padding: 8px 18px; font-size: 14px; }

/* ===== 首屏 ===== */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  color: #fff;
  background:
    radial-gradient(1200px 600px at 80% -10%, rgba(124, 92, 224, 0.55), transparent 60%),
    radial-gradient(900px 500px at 10% 110%, rgba(74, 144, 217, 0.5), transparent 55%),
    linear-gradient(160deg, #1c2333 0%, #232c40 55%, #2a3a54 100%);
  padding-top: var(--nav-h);
}
.hero-inner { max-width: 1100px; margin: 0 auto; padding: 60px 24px; }
.hero-badge {
  display: inline-block;
  padding: 5px 14px;
  font-size: 13px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.1);
  border: 1px solid rgba(255, 255, 255, 0.22);
  margin-bottom: 22px;
}
.hero-title {
  font-size: clamp(34px, 6vw, 56px);
  line-height: 1.2;
  font-weight: 800;
  letter-spacing: 1px;
}
.hero-title em { font-style: normal; background: linear-gradient(90deg, #7cc0ff, #b49bff); -webkit-background-clip: text; background-clip: text; color: transparent; }
.hero-sub {
  max-width: 620px;
  margin-top: 20px;
  font-size: 17px;
  color: rgba(255, 255, 255, 0.82);
}
.hero-actions { display: flex; gap: 16px; margin-top: 36px; flex-wrap: wrap; }
.hero-meta {
  display: flex;
  gap: 22px;
  margin-top: 34px;
  font-size: 14px;
  color: rgba(255, 255, 255, 0.7);
  flex-wrap: wrap;
}

/* ===== 通用区块 ===== */
.section { padding: 90px 24px; }
.section-inner { max-width: 1100px; margin: 0 auto; }
.section-title { font-size: 32px; font-weight: 800; text-align: center; }
.section-desc { text-align: center; color: var(--text-secondary); margin-top: 10px; margin-bottom: 48px; }
.section-alt { background: var(--bg-alt); }

/* ===== 特性卡片 ===== */
.feature-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 22px;
}
.feature-card {
  background: #fff;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px 26px;
  box-shadow: var(--shadow);
  transition: transform .2s ease, box-shadow .25s ease;
  opacity: 0;
  transform: translateY(24px);
}
.feature-card.visible { opacity: 1; transform: translateY(0); }
.feature-card:hover { transform: translateY(-5px); box-shadow: var(--shadow-hover); }
.feature-ico {
  width: 52px; height: 52px;
  display: flex; align-items: center; justify-content: center;
  font-size: 24px;
  color: #fff;
  border-radius: 13px;
  background: linear-gradient(135deg, var(--c, var(--primary)), color-mix(in srgb, var(--c, var(--primary)) 60%, #ffffff));
  margin-bottom: 18px;
}
.feature-card h3 { font-size: 19px; font-weight: 700; margin-bottom: 10px; }
.feature-card p { font-size: 14.5px; color: var(--text-secondary); }

/* ===== 使用技巧 ===== */
.detail-list { max-width: 820px; margin: 0 auto; display: flex; flex-direction: column; gap: 16px; }
.detail-item {
  display: flex;
  align-items: center;
  gap: 24px;
  background: #fff;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px 26px;
  box-shadow: var(--shadow);
}
.detail-key {
  flex-shrink: 0;
  min-width: 120px;
  font-size: 15px;
  font-weight: 700;
  color: var(--primary);
  border-right: 2px solid var(--border);
  padding-right: 24px;
}
.detail-val { font-size: 15px; color: var(--text-secondary); }

/* ===== 下载 ===== */
.section-download {
  background:
    radial-gradient(800px 400px at 20% 0%, rgba(74, 144, 217, 0.08), transparent 60%),
    #fff;
}
.download-card {
  max-width: 900px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 32px;
  flex-wrap: wrap;
  background: linear-gradient(135deg, #1c2333, #2a3a54);
  color: #fff;
  border-radius: 18px;
  padding: 40px 44px;
  box-shadow: var(--shadow-hover);
}
.dl-version { font-size: 24px; font-weight: 800; margin-bottom: 14px; }
.dl-info li {
  position: relative;
  padding-left: 20px;
  margin-bottom: 8px;
  font-size: 14.5px;
  color: rgba(255, 255, 255, 0.82);
}
.dl-info li::before { content: "✓"; position: absolute; left: 0; color: #5fd08a; font-weight: 700; }
.dl-right { text-align: center; }
.dl-note { margin-top: 12px; font-size: 12.5px; color: rgba(255, 255, 255, 0.55); }

/* ===== 页脚 ===== */
.footer { background: #161c28; color: rgba(255, 255, 255, 0.6); }
.footer-inner {
  max-width: 1100px;
  margin: 0 auto;
  padding: 34px 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
}
.footer-brand { display: flex; align-items: center; gap: 8px; font-weight: 700; color: rgba(255,255,255,0.85); }
.footer-copy { font-size: 13.5px; }

/* ===== 响应式 ===== */
@media (max-width: 900px) {
  .feature-grid { grid-template-columns: repeat(2, 1fr); }
  .nav-links { display: none; }
}
@media (max-width: 600px) {
  .feature-grid { grid-template-columns: 1fr; }
  .section { padding: 60px 18px; }
  .detail-item { flex-direction: column; align-items: flex-start; gap: 8px; }
  .detail-key { border-right: none; border-bottom: 2px solid var(--border); padding-right: 0; padding-bottom: 8px; min-width: 0; }
  .download-card { flex-direction: column; text-align: center; padding: 32px 24px; }
}