/* 咔嚓热量 Kacha — 产品官网 v2 */
/* Apple 极简风：纯色块 · 大留白 · 产品即主角 · 滚动叙事 */

@font-face {
  font-family: 'Hanchan';
  src: url('/assets/hanchan.ttf') format('truetype');
  font-weight: 400;
  font-display: swap;
}

:root {
  --orange: #E8894B;
  --orange-hover: #D4743A;
  --black: #000000;
  --near-black: #1d1d1f;
  --white: #ffffff;
  --bg-light: #f5f5f7;
  --text-secondary: rgba(0,0,0,0.56);
  --text-tertiary: rgba(0,0,0,0.42);
  --shadow-card: 0 4px 40px rgba(0,0,0,0.06);
  --transition: cubic-bezier(0.25, 0.1, 0.25, 1);
}

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

html { font-size: 17px; scroll-behavior: smooth; }

body {
  font-family: 'Hanchan', -apple-system, BlinkMacSystemFont, 'SF Pro Text', sans-serif;
  background: var(--white);
  color: var(--near-black);
  line-height: 1.47;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

/* ── 导航 —— Apple 风格毛玻璃 ── */
.nav {
  position: fixed; top: 0; left: 0; right: 0; z-index: 100;
  display: flex; justify-content: center;
  padding: 0 24px; height: 48px;
  background: rgba(255,255,255,0.72);
  backdrop-filter: saturate(180%) blur(20px);
  -webkit-backdrop-filter: saturate(180%) blur(20px);
}
.nav-inner {
  display: flex; align-items: center; justify-content: space-between;
  max-width: 1024px; width: 100%;
}
.nav-brand { display: flex; align-items: center; gap: 8px; text-decoration: none; }
.nav-brand img { width: 28px; height: 28px; border-radius: 7px; }
.nav-brand span { font-size: 15px; font-weight: 600; color: var(--near-black); }
.nav-links { display: flex; gap: 32px; }
.nav-links a { text-decoration: none; font-size: 12px; color: var(--text-secondary); letter-spacing: -0.12px; transition: color .2s; }
.nav-links a:hover { color: var(--orange); }
.nav-cta {
  background: var(--orange); color: var(--white);
  padding: 5px 14px; border-radius: 980px;
  text-decoration: none; font-size: 12px; font-weight: 600;
  transition: background .2s;
}
.nav-cta:hover { background: var(--orange-hover); }

/* ── Section 通用 ── */
.section {
  display: flex; flex-direction: column; align-items: center;
  text-align: center; padding: 120px 24px;
}
.section-dark { background: var(--black); color: var(--white); }
.section-light { background: var(--bg-light); }
.section-white { background: var(--white); }

.eyebrow {
  font-size: 14px; font-weight: 600; color: var(--orange);
  letter-spacing: 0.04em; margin-bottom: 12px;
}

.headline {
  font-size: clamp(36px, 6vw, 56px);
  font-weight: 600; line-height: 1.15;
  letter-spacing: -0.015em;
  max-width: 680px;
}

.subhead {
  font-size: clamp(17px, 2.5vw, 21px);
  font-weight: 400; line-height: 1.47;
  max-width: 520px; margin-top: 14px;
}
.section-dark .subhead { color: rgba(255,255,255,0.64); }
.section-light .subhead, .section-white .subhead { color: var(--text-secondary); }

/* ── 按钮 ── */
.btn {
  display: inline-flex; align-items: center; gap: 6px;
  padding: 10px 22px; border-radius: 980px;
  font-size: 16px; font-weight: 500; text-decoration: none;
  letter-spacing: -0.12px;
  transition: all .2s var(--transition);
}
.btn-primary { background: var(--orange); color: var(--white); }
.btn-primary:hover { background: var(--orange-hover); transform: scale(1.02); }
.btn-outline { background: transparent; color: var(--orange); border: 1px solid var(--orange); }
.btn-outline:hover { background: rgba(232,137,75,0.06); }
.btn-dark { background: var(--white); color: var(--near-black); }
.btn-dark:hover { background: rgba(255,255,255,0.88); transform: scale(1.02); }
.btn-group { display: flex; gap: 14px; margin-top: 24px; flex-wrap: wrap; justify-content: center; }

/* ── Hero ── */
.hero { min-height: 100vh; padding: 100px 24px 80px; }
.hero-img {
  margin-top: 48px; max-width: 960px; width: 100%;
  border-radius: 24px;
  box-shadow: 0 40px 120px rgba(0,0,0,0.12);
}

/* ── 功能网格 ── */
.features {
  display: grid; grid-template-columns: repeat(3, 1fr);
  gap: 24px; max-width: 960px; width: 100%; margin-top: 56px;
}
.feat-card {
  background: var(--white); padding: 36px 28px; border-radius: 16px;
  text-align: left;
  box-shadow: var(--shadow-card);
  transition: transform .3s var(--transition), box-shadow .3s;
}
.feat-card:hover { transform: translateY(-4px); box-shadow: 0 12px 60px rgba(0,0,0,0.1); }
.feat-icon { font-size: 32px; margin-bottom: 16px; }
.feat-card h3 { font-size: 18px; font-weight: 600; margin-bottom: 6px; letter-spacing: -0.01em; }
.feat-card p { font-size: 14px; color: var(--text-secondary); line-height: 1.55; }

/* ── 截图 ── */
.screenshots {
  display: grid; grid-template-columns: repeat(3, 1fr);
  gap: 16px; max-width: 780px; width: 100%; margin-top: 48px;
}
.ss-card {
  border-radius: 20px; overflow: hidden;
  box-shadow: 0 2px 24px rgba(0,0,0,0.06);
  transition: transform .3s var(--transition);
}
.ss-card:hover { transform: scale(1.04); }
.ss-card img { width: 100%; display: block; }

/* ── CTA 区 ── */
.cta { padding: 140px 24px; }

/* ── 页脚 ── */
.footer {
  text-align: center; padding: 32px 24px;
  background: var(--bg-light);
  font-size: 12px; color: var(--text-tertiary); line-height: 2;
}
.footer a { color: var(--text-secondary); text-decoration: none; margin: 0 4px; }
.footer a:hover { color: var(--orange); }
.footer .return-link { text-decoration: underline; }
.footer img.icp-icon { height: 13px; vertical-align: -2px; margin-right: 2px; }

/* ── 滚动动画 ── */
.reveal {
  opacity: 0; transform: translateY(24px);
  transition: opacity .6s var(--transition), transform .6s var(--transition);
}
.reveal.visible { opacity: 1; transform: translateY(0); }

/* ── 响应式 ── */
@media (max-width: 900px) {
  .features { grid-template-columns: repeat(2, 1fr); }
  .screenshots { grid-template-columns: repeat(2, 1fr); }
  .headline { font-size: 36px; }
}
@media (max-width: 600px) {
  .features { grid-template-columns: 1fr; }
  .screenshots { grid-template-columns: 1fr; }
  .nav-links { display: none; }
  .stat-row { flex-direction: column; gap: 20px; }
}