/* ============ Flash_TTS 宣传站 — 深色科技风 ============ */
:root {
  --bg: #0a0e0d;
  --bg-alt: #0d1413;
  --card: rgba(255, 255, 255, 0.03);
  --card-hover: rgba(255, 255, 255, 0.055);
  --line: rgba(255, 255, 255, 0.08);
  --line-strong: rgba(255, 255, 255, 0.14);
  --text: #e8efed;
  --muted: #9aa8a5;
  --brand: #12a894;
  --brand-2: #4a8494;
  --brand-light: #4fe3c9;
  --radius: 16px;
  --shadow: 0 18px 50px rgba(0, 0, 0, 0.45);
  --maxw: 1120px;
  --font: -apple-system, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
}

* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}
a { color: var(--brand-light); text-decoration: none; }
img { max-width: 100%; display: block; }

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 10px 22px;
  border-radius: 10px;
  font-size: 15px;
  font-weight: 600;
  transition: transform 0.15s ease, box-shadow 0.2s ease, background 0.2s ease, border-color 0.2s ease;
  cursor: pointer;
  white-space: nowrap;
}
.btn-lg { padding: 14px 30px; font-size: 16px; border-radius: 12px; }
.btn-primary {
  background: linear-gradient(135deg, #12a894 0%, #0e8f7e 100%);
  color: #fff;
  box-shadow: 0 8px 26px rgba(18, 168, 148, 0.35);
}
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 12px 34px rgba(18, 168, 148, 0.5); }
.btn-ghost {
  background: rgba(255, 255, 255, 0.04);
  color: var(--text);
  border: 1px solid var(--line-strong);
}
.btn-ghost:hover { transform: translateY(-2px); background: rgba(255, 255, 255, 0.09); }

/* ---------- 导航 ---------- */
.nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 100;
  background: rgba(10, 14, 13, 0.78);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--line);
}
.nav-inner {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 0 24px;
  height: 64px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}
.brand { display: flex; align-items: center; gap: 10px; color: var(--text); font-weight: 700; font-size: 18px; letter-spacing: 0.2px; }
.brand-mark { width: 26px; height: 26px; flex-shrink: 0; }
.brand-mark path { stroke: var(--brand-light); }
.nav-links { display: flex; gap: 6px; }
.nav-links a {
  color: var(--muted);
  font-size: 15px;
  padding: 8px 14px;
  border-radius: 8px;
  transition: color 0.15s ease, background 0.15s ease;
}
.nav-links a:hover { color: var(--text); background: rgba(255, 255, 255, 0.06); }
.nav-toggle { display: none; background: none; border: 1px solid var(--line-strong); border-radius: 8px; padding: 8px 10px; cursor: pointer; flex-direction: column; gap: 4px; }
.nav-toggle span { width: 18px; height: 2px; background: var(--text); border-radius: 2px; transition: 0.2s; }

/* ---------- Hero ---------- */
.hero { position: relative; padding: 168px 24px 96px; overflow: hidden; }
.hero-bg { position: absolute; inset: 0; z-index: -1; }
.glow { position: absolute; border-radius: 50%; filter: blur(90px); opacity: 0.35; }
.glow-a { width: 560px; height: 560px; top: -220px; left: -120px; background: radial-gradient(circle, rgba(18, 168, 148, 0.8), transparent 65%); }
.glow-b { width: 520px; height: 520px; top: -80px; right: -160px; background: radial-gradient(circle, rgba(74, 132, 148, 0.7), transparent 65%); }
.grid {
  position: absolute; inset: 0;
  background-image: linear-gradient(rgba(255, 255, 255, 0.035) 1px, transparent 1px),
                    linear-gradient(90deg, rgba(255, 255, 255, 0.035) 1px, transparent 1px);
  background-size: 46px 46px;
  mask-image: radial-gradient(ellipse 90% 70% at 50% 30%, #000 30%, transparent 75%);
  -webkit-mask-image: radial-gradient(ellipse 90% 70% at 50% 30%, #000 30%, transparent 75%);
}
.hero-inner { max-width: var(--maxw); margin: 0 auto; text-align: center; }
.hero-badge {
  display: inline-block;
  padding: 7px 18px;
  border-radius: 999px;
  font-size: 13.5px;
  color: var(--brand-light);
  background: rgba(18, 168, 148, 0.1);
  border: 1px solid rgba(18, 168, 148, 0.35);
  margin-bottom: 26px;
}
.hero h1 { font-size: clamp(34px, 5.6vw, 58px); font-weight: 800; line-height: 1.22; letter-spacing: 0.5px; margin-bottom: 22px; }
.grad {
  background: linear-gradient(100deg, #4fe3c9 0%, #12a894 45%, #4a8494 100%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}
.hero-sub { font-size: 17px; color: var(--muted); margin-bottom: 38px; line-height: 1.9; }
.hero-actions { display: flex; justify-content: center; gap: 16px; flex-wrap: wrap; margin-bottom: 64px; }
.hero-stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 14px;
  max-width: 860px;
  margin: 0 auto;
}
.stat {
  padding: 20px 12px;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  backdrop-filter: blur(6px);
}
.stat b { display: block; font-size: 26px; font-weight: 800; color: var(--brand-light); line-height: 1.2; }
.stat span { font-size: 13px; color: var(--muted); }

/* ---------- 区块 ---------- */
.section { padding: 96px 24px; }
.section-alt { background: var(--bg-alt); }
.section-head { text-align: center; max-width: 640px; margin: 0 auto 56px; }
.section-head h2 { font-size: clamp(26px, 3.4vw, 36px); font-weight: 800; margin-bottom: 12px; }
.section-head p { color: var(--muted); font-size: 15.5px; }

/* ---------- 模块卡片 ---------- */
.module-grid { max-width: var(--maxw); margin: 0 auto; display: grid; grid-template-columns: repeat(3, 1fr); gap: 26px; }
.module-card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 20px;
  overflow: hidden;
  transition: transform 0.25s ease, border-color 0.25s ease, box-shadow 0.25s ease;
}
.module-card:hover { transform: translateY(-6px); border-color: rgba(18, 168, 148, 0.45); box-shadow: var(--shadow); }
.shot { padding: 14px 14px 0; }
.shot img {
  border-radius: 12px;
  border: 1px solid var(--line);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.4);
  aspect-ratio: 4 / 3;
  object-fit: cover;
  object-position: top;
}
.module-body { padding: 22px 24px 26px; }
.module-title { display: flex; align-items: center; gap: 12px; margin-bottom: 10px; }
.module-title h3 { font-size: 20px; font-weight: 700; }
.chip { display: inline-flex; align-items: center; justify-content: center; font-size: 12px; font-weight: 800; letter-spacing: 0.5px; padding: 3px 10px; border-radius: 7px; color: #fff; }
.chip-tts { background: linear-gradient(135deg, #12a894, #0d7f70); }
.chip-asr { background: linear-gradient(135deg, #4a8494, #3a6b78); }
.chip-ocr { background: linear-gradient(135deg, #2fa3c4, #247fa0); }
.module-body p { color: var(--muted); font-size: 14.5px; margin-bottom: 16px; }
.tag-list { list-style: none; display: flex; flex-wrap: wrap; gap: 8px; }
.tag-list li {
  font-size: 12.5px;
  color: var(--brand-light);
  background: rgba(18, 168, 148, 0.09);
  border: 1px solid rgba(18, 168, 148, 0.28);
  padding: 4px 12px;
  border-radius: 999px;
}

/* ---------- 特性 ---------- */
.feature-grid { max-width: var(--maxw); margin: 0 auto; display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px; }
.feature {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 28px 26px;
  transition: transform 0.2s ease, border-color 0.2s ease, background 0.2s ease;
}
.feature:hover { transform: translateY(-4px); border-color: var(--line-strong); background: var(--card-hover); }
.f-icon {
  width: 46px; height: 46px;
  border-radius: 12px;
  display: flex; align-items: center; justify-content: center;
  color: var(--ic);
  background: color-mix(in srgb, var(--ic) 14%, transparent);
  border: 1px solid color-mix(in srgb, var(--ic) 35%, transparent);
  margin-bottom: 16px;
}
.f-icon svg { width: 22px; height: 22px; }
.feature h3 { font-size: 17px; font-weight: 700; margin-bottom: 8px; }
.feature p { color: var(--muted); font-size: 14px; }

/* ---------- 流程 ---------- */
.steps { max-width: var(--maxw); margin: 0 auto; display: flex; align-items: center; justify-content: center; gap: 12px; }
.step {
  flex: 1;
  max-width: 300px;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 30px 26px;
  text-align: center;
}
.step-num {
  width: 44px; height: 44px;
  margin: 0 auto 16px;
  border-radius: 50%;
  display: flex; align-items: center; justify-content: center;
  font-size: 18px; font-weight: 800;
  color: #fff;
  background: linear-gradient(135deg, #12a894, #0d7f70);
  box-shadow: 0 6px 18px rgba(18, 168, 148, 0.4);
}
.step h3 { font-size: 16.5px; margin-bottom: 8px; }
.step p { color: var(--muted); font-size: 13.5px; }
.step-arrow { color: var(--brand); font-size: 26px; font-weight: 300; flex-shrink: 0; opacity: 0.7; }

/* ---------- 下载 ---------- */
.download-grid { max-width: var(--maxw); margin: 0 auto; display: grid; grid-template-columns: 1.1fr 1fr; gap: 26px; }
.download-card, .req-card { background: var(--card); border: 1px solid var(--line); border-radius: 20px; padding: 40px 38px; }
.download-card { text-align: center; }
.dl-icon {
  width: 72px; height: 72px;
  margin: 0 auto 20px;
  border-radius: 18px;
  background: linear-gradient(135deg, rgba(18, 168, 148, 0.16), rgba(74, 132, 148, 0.12));
  border: 1px solid rgba(18, 168, 148, 0.35);
  display: flex; align-items: center; justify-content: center;
}
.dl-icon svg { width: 38px; height: 38px; }
.dl-icon path { stroke: var(--brand-light); }
.download-card h3 { font-size: 22px; margin-bottom: 10px; }
.dl-meta { color: var(--muted); font-size: 14.5px; margin-bottom: 26px; }
.dl-meta b { color: var(--brand-light); }
.dl-note { margin-top: 20px; color: var(--muted); font-size: 13px; line-height: 1.8; }
.req-card h3 { font-size: 18px; margin-bottom: 16px; }
.req-list { list-style: none; }
.req-list li {
  padding: 10px 0 10px 26px;
  position: relative;
  color: var(--muted);
  font-size: 14.5px;
  border-bottom: 1px dashed var(--line);
}
.req-list li:last-child { border-bottom: none; }
.req-list li::before {
  content: "✓";
  position: absolute; left: 2px; top: 10px;
  color: var(--brand-light);
  font-weight: 700;
}
.req-list b { color: var(--text); font-weight: 600; margin-right: 8px; }
.req-note { color: var(--muted); font-size: 13.5px; }

/* ---------- FAQ ---------- */
.faq-list { max-width: 780px; margin: 0 auto; display: flex; flex-direction: column; gap: 14px; }
.faq { background: var(--card); border: 1px solid var(--line); border-radius: 14px; overflow: hidden; }
.faq summary {
  cursor: pointer;
  list-style: none;
  padding: 18px 24px;
  font-size: 15.5px;
  font-weight: 600;
  position: relative;
  transition: color 0.15s ease;
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after {
  content: "+";
  position: absolute; right: 24px; top: 50%;
  transform: translateY(-50%);
  font-size: 20px; font-weight: 400;
  color: var(--brand-light);
  transition: transform 0.2s ease;
}
.faq[open] summary::after { transform: translateY(-50%) rotate(45deg); }
.faq summary:hover { color: var(--brand-light); }
.faq p { padding: 0 24px 20px; color: var(--muted); font-size: 14px; line-height: 1.9; }

/* ---------- 页脚 ---------- */
.footer { border-top: 1px solid var(--line); padding: 46px 24px; text-align: center; }
.footer-brand { display: flex; align-items: center; justify-content: center; gap: 10px; font-size: 17px; font-weight: 700; margin-bottom: 8px; }
.footer-note { color: var(--muted); font-size: 13.5px; margin-bottom: 6px; }
.footer-copy { color: rgba(154, 168, 165, 0.65); font-size: 12.5px; }

/* ---------- 滚动显现 ---------- */
.reveal { opacity: 0; transform: translateY(22px); transition: opacity 0.6s ease, transform 0.6s ease; }
.reveal.in { opacity: 1; transform: none; }

/* ---------- 响应式 ---------- */
@media (max-width: 960px) {
  .module-grid, .feature-grid { grid-template-columns: 1fr 1fr; }
  .download-grid { grid-template-columns: 1fr; }
  .steps { flex-direction: column; }
  .step-arrow { transform: rotate(90deg); }
  .step { max-width: 420px; width: 100%; }
}
@media (max-width: 700px) {
  .nav-links {
    display: none;
    position: absolute; top: 64px; left: 0; right: 0;
    flex-direction: column;
    background: rgba(10, 14, 13, 0.96);
    border-bottom: 1px solid var(--line);
    padding: 12px 20px 20px;
    gap: 4px;
  }
  .nav-links.open { display: flex; }
  .nav-toggle { display: flex; }
  .nav-download { display: none; }
  .module-grid, .feature-grid { grid-template-columns: 1fr; }
  .hero-stats { grid-template-columns: 1fr 1fr; }
  .section { padding: 72px 18px; }
  .hero { padding: 140px 18px 72px; }
}

/* ---------- 开源模型 ---------- */
.model-grid { max-width: var(--maxw); margin: 0 auto; display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; }
.model-card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 20px 22px;
  transition: transform 0.2s ease, border-color 0.2s ease, background 0.2s ease;
}
.model-card:hover { transform: translateY(-4px); border-color: rgba(18, 168, 148, 0.4); background: var(--card-hover); }
.model-head { display: flex; align-items: center; justify-content: space-between; gap: 10px; flex-wrap: wrap; margin-bottom: 10px; }
.model-name { font-size: 15px; font-weight: 700; color: var(--brand-light); font-family: Consolas, "Courier New", monospace; letter-spacing: 0.2px; }
.model-role {
  font-size: 12px; font-weight: 600;
  color: var(--text);
  background: rgba(74, 132, 148, 0.16);
  border: 1px solid rgba(74, 132, 148, 0.35);
  padding: 2px 10px;
  border-radius: 999px;
  white-space: nowrap;
}
.model-card p { color: var(--muted); font-size: 13.5px; }
.model-note { text-align: center; color: var(--muted); font-size: 13px; margin-top: 30px; }

@media (max-width: 960px) {
  .model-grid { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 700px) {
  .model-grid { grid-template-columns: 1fr; }
}

/* ---------- 截图悬停预览窗口 ---------- */
.shot img { cursor: zoom-in; }
.zoom-lens {
  position: fixed; z-index: 300;
  display: none;
  max-width: calc(100vw - 16px);
  max-height: calc(100vh - 16px);
  border-radius: 12px;
  border: 1px solid rgba(255, 255, 255, 0.16);
  background: #0e1312;
  background-repeat: no-repeat;
  box-shadow: 0 24px 80px rgba(0, 0, 0, 0.6);
  pointer-events: none;
}
.zoom-lens.open { display: block; }