/* MeshSolid 宣传页 —— 深色科技风，无外部依赖 */

:root {
  --bg: #0b0e14;
  --bg-alt: #0e1320;
  --card: #131a29;
  --line: #1e2739;
  --text: #e8edf5;
  --muted: #9aa7bd;
  --accent: #2dd4a7;
  --accent-2: #4f8dff;
  --radius: 14px;
}

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

html { scroll-behavior: smooth; }

body {
  font-family: "Segoe UI", "Microsoft YaHei", "PingFang SC", system-ui, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

.container { max-width: 1160px; margin: 0 auto; padding: 0 24px; }
.container-narrow { max-width: 780px; }

/* ---------- 导航 ---------- */
.nav {
  position: sticky; top: 0; z-index: 50;
  background: rgba(11, 14, 20, 0.82);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid transparent;
  transition: border-color .25s;
}
.nav.scrolled { border-bottom-color: var(--line); }
.nav-inner { display: flex; align-items: center; gap: 28px; height: 64px; }
.brand { display: flex; align-items: center; gap: 8px; text-decoration: none; color: var(--text); }
.brand-mark {
  width: 30px; height: 30px; display: grid; place-items: center;
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  border-radius: 8px; font-size: 16px; color: #06251c; font-weight: 700;
}
.brand-name { font-size: 17px; letter-spacing: .3px; }
.brand-name b { color: var(--accent); font-weight: 700; }
.nav-links { display: flex; gap: 22px; margin-left: auto; }
.nav-links a { color: var(--muted); text-decoration: none; font-size: 14px; transition: color .2s; }
.nav-links a:hover { color: var(--text); }

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  padding: 12px 26px; border-radius: 10px; font-size: 15px; font-weight: 600;
  text-decoration: none; cursor: pointer; border: 1px solid transparent;
  transition: transform .15s, box-shadow .2s, background .2s;
}
.btn-primary {
  background: linear-gradient(135deg, var(--accent), #1fb98d);
  color: #06251c;
  box-shadow: 0 6px 24px rgba(45, 212, 167, .25);
}
.btn-primary:hover { transform: translateY(-1px); box-shadow: 0 10px 30px rgba(45, 212, 167, .35); }
.btn-ghost { background: transparent; color: var(--text); border-color: var(--line); }
.btn-ghost:hover { border-color: var(--muted); }
.btn-sm { padding: 8px 18px; font-size: 14px; }
.btn-lg { padding: 15px 36px; font-size: 16px; }
.btn-block { width: 100%; }
.btn-disabled { opacity: .45; cursor: default; pointer-events: none; }

/* ---------- Hero ---------- */
.hero { padding: 84px 0 60px; background:
  radial-gradient(60% 90% at 80% 0%, rgba(79, 141, 255, .12), transparent 60%),
  radial-gradient(50% 80% at 10% 10%, rgba(45, 212, 167, .10), transparent 60%);
}
.hero-inner { display: grid; grid-template-columns: 1.05fr 1fr; gap: 48px; align-items: center; }
.badge {
  display: inline-flex; align-items: center; gap: 8px;
  border: 1px solid var(--line); background: rgba(255,255,255,.03);
  color: var(--muted); border-radius: 999px; padding: 6px 14px; font-size: 13px;
  margin-bottom: 22px;
}
.dot { width: 8px; height: 8px; border-radius: 50%; background: var(--accent); box-shadow: 0 0 10px var(--accent); }
h1 { font-size: clamp(30px, 4.2vw, 46px); line-height: 1.25; font-weight: 800; letter-spacing: .5px; }
h1 em { font-style: normal; background: linear-gradient(90deg, var(--accent), var(--accent-2)); -webkit-background-clip: text; background-clip: text; color: transparent; }
.lead { color: var(--muted); font-size: 16.5px; margin: 20px 0 28px; }
.lead b { color: var(--text); }
.hero-cta { display: flex; gap: 14px; flex-wrap: wrap; }
.hero-chips { display: flex; flex-wrap: wrap; gap: 10px; list-style: none; margin-top: 26px; }
.hero-chips li {
  font-size: 13px; color: var(--muted); border: 1px solid var(--line);
  padding: 6px 12px; border-radius: 8px; background: rgba(255,255,255,.02);
}

.hero-shot { position: relative; }
.hero-shot img {
  width: 100%; display: block; border-radius: var(--radius);
  border: 1px solid var(--line);
  box-shadow: 0 30px 80px rgba(0, 0, 0, .55), 0 0 0 1px rgba(255,255,255,.03) inset;
}
.hero-shot figcaption { text-align: center; color: var(--muted); font-size: 13px; margin-top: 12px; }

/* ---------- 区块 ---------- */
.section { padding: 78px 0; }
.section-alt { background: var(--bg-alt); border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.eyebrow { color: var(--accent); font-size: 13px; font-weight: 700; letter-spacing: 2px; margin-bottom: 10px; }
h2 { font-size: clamp(24px, 3vw, 32px); font-weight: 800; letter-spacing: .3px; }
.section-lead { color: var(--muted); margin: 12px 0 40px; max-width: 640px; }

.grid { display: grid; gap: 18px; }
.grid-4 { grid-template-columns: repeat(4, 1fr); }
.grid-2 { grid-template-columns: repeat(2, 1fr); }

.card {
  background: var(--card); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 26px 24px; transition: transform .18s, border-color .18s;
}
.card:hover { transform: translateY(-3px); border-color: #2a3850; }
.card-icon {
  width: 44px; height: 44px; display: grid; place-items: center; font-size: 22px;
  background: rgba(45, 212, 167, .1); border: 1px solid rgba(45, 212, 167, .25);
  border-radius: 10px; margin-bottom: 16px;
}
.card h3 { font-size: 17px; margin-bottom: 8px; }
.card p { color: var(--muted); font-size: 14px; }

/* ---------- 步骤 ---------- */
.steps { margin-top: 36px; }
.step { position: relative; background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); padding: 24px; }
.step-num {
  display: inline-grid; place-items: center; width: 32px; height: 32px; border-radius: 50%;
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  color: #06251c; font-weight: 800; margin-bottom: 12px;
}
.step h3 { font-size: 16px; margin-bottom: 6px; }
.step p { color: var(--muted); font-size: 14px; }

.metric-strip {
  display: grid; grid-template-columns: repeat(4, 1fr); gap: 18px; margin-top: 40px;
  background: linear-gradient(135deg, rgba(45,212,167,.07), rgba(79,141,255,.07));
  border: 1px solid var(--line); border-radius: var(--radius); padding: 28px;
}
.metric { text-align: center; }
.metric b { display: block; font-size: 30px; background: linear-gradient(90deg, var(--accent), var(--accent-2)); -webkit-background-clip: text; background-clip: text; color: transparent; }
.metric span { color: var(--muted); font-size: 13px; }

/* ---------- 下载 ---------- */
.dl-grid { margin-top: 12px; }
.dl-card { display: flex; flex-direction: column; gap: 16px; }
.dl-head { display: flex; align-items: center; gap: 14px; }
.dl-icon { font-size: 34px; }
.dl-head h3 { font-size: 18px; }
.dl-head p { color: var(--muted); font-size: 13px; }
.dl-note { color: var(--muted); font-size: 13px; }
.dl-note code { background: rgba(255,255,255,.06); padding: 2px 6px; border-radius: 5px; font-size: 12.5px; }
.dl-disabled { opacity: .75; }

/* ---------- FAQ ---------- */
.faq {
  border: 1px solid var(--line); border-radius: 12px; background: var(--card);
  padding: 0 22px; margin-top: 14px;
}
.faq[open] { border-color: #2a3850; }
.faq summary {
  list-style: none; cursor: pointer; padding: 18px 0; font-weight: 600;
  display: flex; justify-content: space-between; align-items: center; gap: 12px;
}
.faq summary::-webkit-details-marker { display: none; }
.faq-x { color: var(--accent); font-size: 20px; transition: transform .2s; }
.faq[open] .faq-x { transform: rotate(45deg); }
.faq p { color: var(--muted); font-size: 14.5px; padding-bottom: 18px; }

/* ---------- CTA ---------- */
.cta { background:
  radial-gradient(50% 100% at 50% 0%, rgba(45, 212, 167, .13), transparent 70%), var(--bg-alt);
  text-align: center;
}
.cta-inner { padding: 20px 0; }
.cta p { color: var(--muted); margin: 14px 0 30px; }

/* ---------- 页脚 ---------- */
.footer { border-top: 1px solid var(--line); padding: 40px 0 28px; background: var(--bg); }
.footer-inner { display: flex; justify-content: space-between; gap: 24px; flex-wrap: wrap; }
.footer p { color: var(--muted); font-size: 13.5px; margin-top: 6px; }
.footer a { color: var(--muted); text-decoration: none; font-size: 13.5px; }
.footer a:hover { color: var(--text); }
.footer-legal { margin-top: 22px; padding-top: 18px; border-top: 1px solid var(--line); }
.footer-legal p { font-size: 12.5px; }

/* ---------- 响应式 ---------- */
@media (max-width: 960px) {
  .hero-inner { grid-template-columns: 1fr; }
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .metric-strip { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 620px) {
  .nav-links { display: none; }
  .grid-4, .grid-2 { grid-template-columns: 1fr; }
  .hero { padding: 56px 0 40px; }
  .section { padding: 56px 0; }
}