:root {
  --bg: #070b14;
  --bg-soft: #0d1322;
  --panel: rgba(20, 28, 46, 0.72);
  --panel-border: rgba(120, 160, 255, 0.14);
  --text: #e6edf6;
  --text-dim: #9fb0c8;
  --cyan: #22d3ee;
  --violet: #a855f7;
  --cyan-soft: rgba(34, 211, 238, 0.14);
  --violet-soft: rgba(168, 85, 247, 0.16);
  --radius: 16px;
  --maxw: 1120px;
}

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

html { scroll-behavior: smooth; }

body {
  font-family: -apple-system, "PingFang SC", "Microsoft YaHei", system-ui, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  overflow-x: hidden;
}

.bg-glow {
  position: fixed;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  background:
    radial-gradient(620px 420px at 12% 8%, rgba(34, 211, 238, 0.16), transparent 60%),
    radial-gradient(680px 480px at 88% 12%, rgba(168, 85, 247, 0.16), transparent 60%),
    radial-gradient(900px 600px at 50% 100%, rgba(34, 211, 238, 0.08), transparent 60%);
}

.container { width: 100%; max-width: var(--maxw); margin: 0 auto; padding: 0 20px; position: relative; z-index: 1; }

/* 导航 */
.nav {
  position: sticky; top: 0; z-index: 50;
  backdrop-filter: blur(12px);
  background: rgba(7, 11, 20, 0.72);
  border-bottom: 1px solid var(--panel-border);
}
.nav-inner { display: flex; align-items: center; justify-content: space-between; height: 64px; }
.brand { display: flex; align-items: center; gap: 10px; text-decoration: none; color: var(--text); }
.brand-mark {
  width: 34px; height: 34px; border-radius: 9px;
  display: grid; place-items: center; font-weight: 800; font-size: 18px; color: #051018;
  background: linear-gradient(135deg, var(--cyan), var(--violet));
  box-shadow: 0 6px 20px rgba(34, 211, 238, 0.35);
}
.brand-name { font-weight: 700; letter-spacing: 1px; }
.nav-links { display: flex; gap: 28px; }
.nav-links a { color: var(--text-dim); text-decoration: none; font-size: 15px; transition: color .2s; }
.nav-links a:hover { color: var(--cyan); }

/* 按钮 */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  padding: 11px 22px; border-radius: 999px; font-size: 15px; font-weight: 600;
  text-decoration: none; cursor: pointer; border: 1px solid transparent; transition: transform .15s, box-shadow .2s, background .2s;
}
.btn:hover { transform: translateY(-1px); }
.btn-primary {
  color: #04121a;
  background: linear-gradient(135deg, var(--cyan), var(--violet));
  box-shadow: 0 8px 26px rgba(34, 211, 238, 0.32);
}
.btn-ghost { color: var(--text); border-color: var(--panel-border); background: rgba(255,255,255,0.03); }
.btn-ghost:hover { border-color: var(--cyan); color: var(--cyan); }
.btn-block { width: 100%; }
.nav-cta { padding: 8px 18px; font-size: 14px; }

/* Hero */
.hero { padding: 92px 0 64px; text-align: center; }
.tag {
  display: inline-block; padding: 6px 14px; border-radius: 999px; font-size: 13px;
  color: var(--cyan); background: var(--cyan-soft); border: 1px solid rgba(34,211,238,0.3);
  margin-bottom: 22px; letter-spacing: .5px;
}
.hero-title {
  font-size: clamp(48px, 9vw, 96px); font-weight: 800; letter-spacing: 4px; line-height: 1.05;
  background: linear-gradient(120deg, #ffffff 10%, var(--cyan) 50%, var(--violet) 90%);
  -webkit-background-clip: text; background-clip: text; -webkit-text-fill-color: transparent;
}
.hero-sub { font-size: clamp(18px, 3vw, 26px); margin-top: 14px; color: var(--text); font-weight: 600; }
.hl { color: var(--cyan); }
.hero-desc { max-width: 680px; margin: 18px auto 0; color: var(--text-dim); font-size: 16px; }
.hero-actions { margin-top: 30px; display: flex; gap: 14px; justify-content: center; flex-wrap: wrap; }
.hero-stats { margin-top: 54px; display: flex; gap: 18px; justify-content: center; flex-wrap: wrap; }
.stat {
  min-width: 132px; padding: 18px 22px; border-radius: var(--radius);
  background: var(--panel); border: 1px solid var(--panel-border); backdrop-filter: blur(8px);
}
.stat-num { font-size: 26px; font-weight: 800; background: linear-gradient(120deg, var(--cyan), var(--violet)); -webkit-background-clip: text; background-clip: text; -webkit-text-fill-color: transparent; }
.stat-label { font-size: 13px; color: var(--text-dim); margin-top: 4px; }

/* 区块 */
.section { padding: 72px 0; position: relative; z-index: 1; }
.section-alt { background: linear-gradient(180deg, rgba(13,19,34,0.0), rgba(13,19,34,0.6), rgba(13,19,34,0.0)); }
.section-title { font-size: clamp(26px, 4vw, 38px); font-weight: 800; text-align: center; }
.section-title.left { text-align: left; }
.section-sub { text-align: center; color: var(--text-dim); margin-top: 10px; font-size: 16px; }

.grid { display: grid; gap: 20px; margin-top: 40px; }
.grid-2 { grid-template-columns: repeat(2, 1fr); }

/* 卡片 */
.card {
  position: relative; padding: 28px; border-radius: var(--radius);
  background: var(--panel); border: 1px solid var(--panel-border); backdrop-filter: blur(8px);
  transition: transform .2s, border-color .2s, box-shadow .2s;
}
.card:hover { transform: translateY(-4px); border-color: rgba(34,211,238,0.4); box-shadow: 0 14px 40px rgba(0,0,0,0.35); }
.card-icon { font-size: 30px; margin-bottom: 12px; }
.card h3 { font-size: 20px; margin-bottom: 10px; }
.card p { color: var(--text-dim); font-size: 15px; }
.card-tag {
  display: inline-block; margin-top: 16px; padding: 5px 12px; border-radius: 999px;
  font-size: 13px; font-weight: 600; color: #042; background: linear-gradient(135deg, var(--cyan), #6ee7b7);
}
.card-tag-soon { color: #2a1a04; background: linear-gradient(135deg, #fbbf24, #f59e0b); }
.card-tag-link { color: #fff; background: linear-gradient(135deg, var(--violet), #7c3aed); text-decoration: none; }

/* 课程 */
.course { display: flex; flex-direction: column; }
.course-badge {
  align-self: flex-start; font-size: 12px; font-weight: 700; letter-spacing: 1px;
  color: var(--cyan); background: var(--cyan-soft); padding: 4px 10px; border-radius: 8px; margin-bottom: 12px;
}
.course-desc { flex: 1; }
.course-price { font-size: 24px; font-weight: 800; margin: 16px 0; color: #fff; }
.price-num { color: var(--cyan); }
.price-sub { font-size: 13px; font-weight: 400; color: var(--text-dim); margin-left: 6px; }
.course-list { list-style: none; margin: 0 0 20px; }
.course-list li { position: relative; padding-left: 22px; color: var(--text-dim); font-size: 14px; margin-bottom: 8px; }
.course-list li::before { content: "✓"; position: absolute; left: 0; color: var(--cyan); font-weight: 700; }
.note { text-align: center; color: var(--text-dim); font-size: 14px; margin-top: 26px; }

/* 表单 + 流程 */
.form-layout { align-items: start; }
.flow-title { font-size: 20px; margin-bottom: 18px; }
.steps { list-style: none; }
.steps li { display: flex; gap: 16px; padding: 14px 0; border-bottom: 1px dashed var(--panel-border); }
.steps li:last-child { border-bottom: none; }
.step-no {
  flex: none; width: 34px; height: 34px; border-radius: 50%; display: grid; place-items: center;
  font-weight: 700; color: #04121a; background: linear-gradient(135deg, var(--cyan), var(--violet));
}
.steps b { font-size: 16px; }
.steps p { color: var(--text-dim); font-size: 14px; }

.lead-form { background: var(--panel); border: 1px solid var(--panel-border); border-radius: var(--radius); padding: 26px; backdrop-filter: blur(8px); }
.field { margin-bottom: 16px; }
.field label { display: block; font-size: 14px; color: var(--text-dim); margin-bottom: 7px; }
.field input, .field select, .field textarea {
  width: 100%; padding: 12px 14px; border-radius: 10px; font-size: 15px; font-family: inherit;
  background: rgba(7, 11, 20, 0.6); color: var(--text); border: 1px solid var(--panel-border); outline: none; transition: border-color .2s;
}
.field input:focus, .field select:focus, .field textarea:focus { border-color: var(--cyan); }
.field textarea { resize: vertical; }
.form-hint { font-size: 14px; margin-top: 12px; min-height: 20px; }
.form-hint.ok { color: #6ee7b7; }
.form-hint.err { color: #fca5a5; }

/* 关于 / 联系 */
.about-inner { display: grid; grid-template-columns: 1.4fr 1fr; gap: 40px; align-items: center; }
.about-desc { color: var(--text-dim); margin: 14px 0; font-size: 15px; }
.contact-list { margin-top: 22px; display: grid; gap: 14px; }
.contact-item { display: flex; gap: 14px; align-items: flex-start; }
.contact-ic { font-size: 22px; }
.contact-item b { font-size: 15px; }
.contact-item p { color: var(--text-dim); font-size: 14px; }
.contact-item a { color: var(--cyan); text-decoration: none; }

.about-qr { text-align: center; }
.qr-box {
  position: relative;
  width: 220px; height: 220px; margin: 0 auto; border-radius: 18px;
  background: rgba(255,255,255,0.04); border: 1px solid var(--panel-border);
  display: grid; place-items: center; padding: 16px;
}
.qr-img { position: absolute; inset: 12px; width: calc(100% - 24px); height: calc(100% - 24px); object-fit: contain; border-radius: 10px; background: #fff; }
.qr-placeholder { position: relative; color: var(--text-dim); font-size: 13px; text-align: center; line-height: 1.7; }
.qr-cap { color: var(--text-dim); font-size: 13px; margin-top: 14px; }

/* 页脚 */
.footer { border-top: 1px solid var(--panel-border); padding: 26px 0; margin-top: 30px; }
.footer-inner { display: flex; justify-content: space-between; flex-wrap: wrap; gap: 8px; color: var(--text-dim); font-size: 13px; }
.footer-meta { display: inline-flex; align-items: center; flex-wrap: wrap; gap: 6px; }
.footer-meta a { color: var(--text-dim); text-decoration: none; transition: color .2s; }
.footer-meta a:hover { color: var(--cyan); }
.footer-dot { opacity: .5; }

/* 响应式 */
@media (max-width: 860px) {
  .nav-links { display: none; }
  .grid-2 { grid-template-columns: 1fr; }
  .about-inner { grid-template-columns: 1fr; }
  .hero { padding: 64px 0 48px; }
}