/* ===== Eureka 官网样式（Apple 风格） ===== */
:root {
  --font: -apple-system, BlinkMacSystemFont, "SF Pro Text", "Segoe UI",
    "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --bg: #ffffff;
  --bg-alt: #f5f5f7;
  --text: #1d1d1f;
  --text-soft: #6e6e73;
  --accent: #0071e3;
  --accent-strong: #0077ed;
  --border: rgba(0, 0, 0, 0.08);
  --radius: 16px;
  --shadow: 0 8px 30px rgba(0, 0, 0, 0.08);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: var(--font);
  color: var(--text);
  background: var(--bg);
  font-size: 16px;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

/* ===== 顶部导航 ===== */
.nav {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255, 255, 255, 0.78);
  backdrop-filter: saturate(180%) blur(20px);
  -webkit-backdrop-filter: saturate(180%) blur(20px);
  border-bottom: 1px solid var(--border);
}
.nav-inner {
  max-width: 1080px;
  margin: 0 auto;
  padding: 10px 24px;
  display: flex;
  align-items: center;
  gap: 24px;
}
.brand {
  display: flex;
  align-items: center;
  gap: 8px;
  text-decoration: none;
  color: var(--text);
  font-weight: 700;
  font-size: 18px;
}
.brand-icon { width: 28px; height: 28px; border-radius: 7px; }
.brand-name { letter-spacing: 0.2px; }
.nav-links { display: flex; gap: 20px; margin-left: auto; }
.nav-links a {
  text-decoration: none;
  color: var(--text-soft);
  font-size: 14px;
  transition: color 0.15s;
}
.nav-links a:hover { color: var(--text); }
@media (max-width: 640px) {
  .nav-links { display: none; }
}

/* ===== 按钮 ===== */
.btn {
  display: inline-flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 2px;
  text-decoration: none;
  border-radius: 12px;
  font-weight: 600;
  transition: transform 0.06s ease, background 0.15s ease, box-shadow 0.15s ease;
}
.btn:active { transform: scale(0.97); }
.btn-primary {
  background: var(--accent);
  color: #fff;
  border: none;
}
.btn-primary:hover { background: var(--accent-strong); }
.btn-sm { height: 34px; padding: 0 16px; font-size: 13px; }
.btn-lg { height: 56px; padding: 0 32px; font-size: 17px; border-radius: 14px; }
.btn-sub { font-size: 12px; font-weight: 400; opacity: 0.85; }

/* ===== 首屏 ===== */
.hero {
  text-align: center;
  padding: 90px 24px 70px;
  background:
    radial-gradient(1200px 500px at 50% -100px, rgba(0, 113, 227, 0.08), transparent 60%),
    var(--bg);
}
.hero-icon {
  width: 96px;
  height: 96px;
  border-radius: 22px;
  box-shadow: var(--shadow);
}
.hero-title { font-size: 56px; font-weight: 800; margin: 24px 0 6px; letter-spacing: 1px; }
.hero-tagline { font-size: 22px; color: var(--text-soft); margin: 0 0 20px; }
.hero-desc { font-size: 17px; color: var(--text-soft); margin: 0 0 36px; }
.hero-desc b { color: var(--text); }
.hero-note { font-size: 13px; color: var(--text-soft); margin: 18px 0 0; }

/* ===== 通用区块 ===== */
.section { padding: 84px 24px; }
.section-alt { background: var(--bg-alt); }
.section-inner { max-width: 1080px; margin: 0 auto; }
.section-title { font-size: 34px; font-weight: 800; text-align: center; margin: 0 0 12px; }
.section-sub { text-align: center; color: var(--text-soft); margin: 0 0 48px; font-size: 16px; }
.section-sub b { color: var(--text); }

/* ===== 功能卡片 ===== */
.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 20px;
}
.card {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px 26px;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.04);
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}
.card:hover { transform: translateY(-4px); box-shadow: var(--shadow); }
.card-icon { font-size: 32px; margin-bottom: 12px; }
.card h3 { font-size: 18px; margin: 0 0 8px; }
.card p { font-size: 14px; color: var(--text-soft); margin: 0; line-height: 1.75; }

/* ===== 为什么选择 ===== */
.why-row {
  display: flex;
  gap: 28px;
  align-items: center;
  max-width: 1020px;
  margin: 0 auto 44px;
}
.why-row.rev { flex-direction: row-reverse; }
.why-num {
  flex: none;
  width: 46px;
  height: 46px;
  border-radius: 12px;
  background: var(--accent);
  color: #fff;
  font-weight: 800;
  font-size: 15px;
  display: flex;
  align-items: center;
  justify-content: center;
}
.why-body { flex: 1; min-width: 0; }
.why-body h3 { font-size: 20px; margin: 0 0 6px; }
.why-body p { color: var(--text-soft); margin: 0; font-size: 15px; }

/* 界面截图位（图片缺失时显示占位框） */
.why-shot {
  flex: 0 0 400px;
  aspect-ratio: 16 / 10;
  border-radius: 14px;
  overflow: hidden;
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
  background: var(--bg);
}
.why-shot img { width: 100%; height: 100%; object-fit: cover; display: block; }
.why-shot .shot-placeholder {
  width: 100%;
  height: 100%;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 8px;
  color: var(--text-soft);
  font-size: 14px;
  text-align: center;
  padding: 16px;
  border: 2px dashed var(--border);
  border-radius: 14px;
  background: var(--bg-alt);
}
.why-shot .shot-placeholder .ph-icon { font-size: 30px; }
.why-shot .shot-placeholder code {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 1px 6px;
  font-size: 12px;
}
@media (max-width: 860px) {
  .why-row, .why-row.rev { flex-direction: column; }
  .why-shot { flex: none; width: 100%; max-width: 480px; }
}

/* ===== 下载 ===== */
.download-card {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 32px 36px;
  max-width: 760px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  flex-wrap: wrap;
}
.download-name { font-size: 22px; font-weight: 800; margin-bottom: 10px; }
.download-meta { list-style: none; margin: 0; padding: 0; font-size: 14px; color: var(--text-soft); }
.download-meta li { margin: 3px 0; }
.download-hint { text-align: center; color: var(--text-soft); font-size: 14px; margin: 28px 0 0; }
.download-hint code, .support-note code {
  background: var(--bg-alt);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 1px 6px;
  font-size: 13px;
}

/* ===== 赞助 ===== */
.support-box {
  display: flex;
  gap: 36px;
  justify-content: center;
  flex-wrap: wrap;
  margin-bottom: 18px;
}
.support-qr {
  width: 150px;
  aspect-ratio: 1080 / 1616; /* 收款码竖版比例 */
  border: 2px dashed var(--border);
  border-radius: var(--radius);
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
  background: var(--bg);
}
.qr-img { width: 100%; height: 100%; object-fit: contain; }
.qr-img.error {
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 14px;
  color: var(--text-soft);
  text-align: center;
  padding: 12px;
}
.support-note { text-align: center; color: var(--text-soft); font-size: 13px; }

/* ===== 图片灯箱（点击放大） ===== */
.lightbox {
  position: fixed;
  inset: 0;
  z-index: 300;
  background: rgba(0, 0, 0, 0.75);
  backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: zoom-out;
}
.lightbox img {
  max-width: 92vw;
  max-height: 90vh;
  border-radius: 10px;
  box-shadow: 0 20px 80px rgba(0, 0, 0, 0.5);
  cursor: default;
}
.lightbox-close {
  position: absolute;
  top: 16px;
  right: 22px;
  width: 40px;
  height: 40px;
  border-radius: 50%;
  border: none;
  background: rgba(255, 255, 255, 0.15);
  color: #fff;
  font-size: 20px;
  cursor: pointer;
}
.lightbox-close:hover { background: rgba(255, 255, 255, 0.3); }

/* ===== 页脚 ===== */
.footer {
  border-top: 1px solid var(--border);
  background: var(--bg-alt);
  padding: 40px 24px;
}
.footer-inner { max-width: 1080px; margin: 0 auto; text-align: center; }
.footer-brand {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  font-weight: 700;
  margin-bottom: 10px;
}
.footer-icon { width: 24px; height: 24px; border-radius: 6px; }
.footer-note { color: var(--text-soft); font-size: 14px; margin: 0 0 8px; }
.footer-copy { color: var(--text-soft); font-size: 12px; margin: 0; }