/* ========== 全局样式 ========== */
* { margin: 0; padding: 0; box-sizing: border-box; }

:root {
  --red: #c0002a;
  --red-dark: #900020;
  --red-light: #f5e0e5;
  --text: #1a1a2e;
  --text-light: #555;
  --bg: #f8f9fa;
  --white: #fff;
  --border: #e8e8e8;
  --shadow: 0 4px 20px rgba(0,0,0,0.08);
  --radius: 12px;
}

html { scroll-behavior: smooth; }

body {
  font-family: 'Microsoft YaHei', '微软雅黑', 'PingFang SC', sans-serif;
  color: var(--text);
  line-height: 1.7;
  background: var(--white);
}

.container { max-width: 1200px; margin: 0 auto; padding: 0 24px; }

/* ========== 导航 ========== */
.navbar {
  position: fixed; top: 0; left: 0; right: 0; z-index: 999;
  background: rgba(255,255,255,0.95);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid transparent;
  transition: all 0.3s;
}
.navbar.scrolled {
  border-bottom-color: var(--border);
  box-shadow: 0 2px 20px rgba(0,0,0,0.1);
}
.nav-inner {
  display: flex; align-items: center; justify-content: space-between;
  height: 64px;
}
.logo { font-size: 22px; font-weight: 700; color: var(--text); }
.logo span { color: var(--red); }
.nav-links { display: flex; list-style: none; gap: 4px; }
.nav-links a {
  padding: 6px 14px; border-radius: 6px;
  font-size: 14px; color: var(--text-light);
  text-decoration: none; transition: all 0.2s;
}
.nav-links a:hover { color: var(--red); background: var(--red-light); }

/* ========== Hero ========== */
.hero {
  min-height: 100vh;
  background: linear-gradient(135deg, #0a0a1a 0%, #1a0010 40%, #2a0015 100%);
  display: flex; flex-direction: column;
  justify-content: center; align-items: center;
  text-align: center; padding: 100px 24px 60px;
  position: relative; overflow: hidden;
}
.hero::before {
  content: '';
  position: absolute; inset: 0;
  background: radial-gradient(ellipse at 30% 50%, rgba(192,0,42,0.3) 0%, transparent 60%),
              radial-gradient(ellipse at 70% 30%, rgba(192,0,42,0.15) 0%, transparent 50%);
}
.hero-content { position: relative; z-index: 1; max-width: 800px; margin-bottom: 60px; }
.hero-content h1 {
  font-size: clamp(32px, 5vw, 56px);
  color: var(--white);
  font-weight: 700;
  line-height: 1.3;
  margin-bottom: 24px;
}
.hero-content .highlight {
  background: linear-gradient(90deg, #ff6b6b, #c0002a);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}
.hero-sub { font-size: 18px; color: rgba(255,255,255,0.75); margin-bottom: 40px; }
.hero-btns { display: flex; gap: 16px; justify-content: center; flex-wrap: wrap; }
.btn-primary {
  background: var(--red); color: var(--white);
  padding: 14px 32px; border-radius: 8px;
  font-size: 16px; font-weight: 600;
  text-decoration: none; border: none; cursor: pointer;
  transition: all 0.2s;
}
.btn-primary:hover { background: var(--red-dark); transform: translateY(-2px); box-shadow: 0 8px 24px rgba(192,0,42,0.4); }
.btn-outline {
  background: transparent; color: var(--white);
  padding: 14px 32px; border-radius: 8px;
  font-size: 16px; font-weight: 600;
  text-decoration: none; border: 2px solid rgba(255,255,255,0.5);
  transition: all 0.2s;
}
.btn-outline:hover { border-color: var(--white); background: rgba(255,255,255,0.1); }

.hero-stats {
  position: relative; z-index: 1;
  display: flex; gap: 40px; flex-wrap: wrap; justify-content: center;
}
.stat-item { text-align: center; }
.stat-num { display: block; font-size: 42px; font-weight: 800; color: var(--white); }
.stat-num em { font-size: 22px; font-style: normal; color: rgba(255,255,255,0.7); }
.stat-label { display: block; font-size: 13px; color: rgba(255,255,255,0.6); margin-top: 4px; }

/* ========== 通用 Section ========== */
.section { padding: 80px 0; }
.section:nth-child(even) { background: var(--bg); }
.section-header { text-align: center; margin-bottom: 50px; }
.section-header h2 { font-size: 34px; font-weight: 700; margin-bottom: 12px; }
.section-header h2::after {
  content: '';
  display: block; width: 48px; height: 3px;
  background: var(--red); margin: 12px auto 0;
  border-radius: 2px;
}
.section-sub { font-size: 16px; color: var(--text-light); }

/* ========== 公司简介 ========== */
.about-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 60px; align-items: start; }
.about-text p { margin-bottom: 16px; color: var(--text-light); line-height: 1.8; }
.mission-cards { display: flex; gap: 16px; margin-top: 28px; flex-wrap: wrap; }
.mission-card {
  flex: 1; min-width: 120px;
  background: var(--white);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px 16px;
  text-align: center;
  box-shadow: var(--shadow);
}
.mission-icon { font-size: 28px; margin-bottom: 8px; }
.mission-card h4 { font-size: 14px; color: var(--red); font-weight: 700; margin-bottom: 6px; }
.mission-card p { font-size: 13px; color: var(--text-light); }

.about-framework {
  background: var(--white);
  border-radius: var(--radius);
  padding: 32px;
  box-shadow: var(--shadow);
}
.about-framework h3 { font-size: 20px; font-weight: 700; margin-bottom: 24px; }
.fw-item {
  display: flex; align-items: center; gap: 16px;
  padding: 14px 0; border-bottom: 1px solid var(--border);
}
.fw-item:last-child { border-bottom: none; }
.fw-icon { font-size: 28px; flex-shrink: 0; }
.fw-item strong { display: block; font-size: 15px; font-weight: 700; margin-bottom: 2px; }
.fw-item span { font-size: 13px; color: var(--text-light); }

/* ========== 产品交付形式 ========== */
.delivery-grid {
  display: flex; gap: 16px; flex-wrap: wrap; justify-content: center;
}
.delivery-card {
  flex: 1; min-width: 180px; max-width: 220px;
  background: var(--white);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px 20px;
  text-align: center;
  transition: all 0.3s;
}
.delivery-card:hover { box-shadow: var(--shadow); transform: translateY(-4px); }
.delivery-card.featured {
  background: linear-gradient(135deg, var(--red), var(--red-dark));
  color: var(--white); border-color: var(--red);
}
.delivery-num { font-size: 36px; font-weight: 800; color: var(--border); margin-bottom: 10px; }
.delivery-card.featured .delivery-num { color: rgba(255,255,255,0.3); }
.delivery-card h3 { font-size: 17px; font-weight: 700; margin-bottom: 8px; }
.delivery-time { font-size: 12px; color: var(--red); font-weight: 600; margin-bottom: 10px; }
.delivery-card.featured .delivery-time { color: rgba(255,255,255,0.8); }
.delivery-card p { font-size: 13px; color: var(--text-light); line-height: 1.6; }
.delivery-card.featured p { color: rgba(255,255,255,0.85); }

/* ========== 课程系列 ========== */
.course-tabs {}
.tab-nav {
  display: flex; gap: 8px; margin-bottom: 32px;
  border-bottom: 2px solid var(--border);
  flex-wrap: wrap;
}
.tab-btn {
  padding: 12px 24px; border: none; background: none;
  font-size: 15px; font-weight: 600; color: var(--text-light);
  cursor: pointer; border-bottom: 2px solid transparent;
  margin-bottom: -2px; transition: all 0.2s;
}
.tab-btn.active { color: var(--red); border-bottom-color: var(--red); }
.tab-btn:hover { color: var(--red); }
.tab-content { display: none; }
.tab-content.active { display: block; }

.course-intro { margin-bottom: 28px; }
.course-intro-text h3 { font-size: 20px; font-weight: 700; margin-bottom: 10px; }
.course-intro-text p { color: var(--text-light); margin-bottom: 14px; }
.problem-tags { display: flex; flex-wrap: wrap; gap: 8px; }
.tag {
  background: var(--red-light); color: var(--red);
  font-size: 12px; font-weight: 600;
  padding: 4px 12px; border-radius: 20px;
}
.course-list { display: flex; flex-direction: column; gap: 12px; }
.course-item {
  display: flex; align-items: center; gap: 12px;
  background: var(--white);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 14px 20px;
  transition: all 0.2s;
}
.course-item:hover { border-color: var(--red); box-shadow: 0 2px 10px rgba(192,0,42,0.1); }
.fire { font-size: 16px; flex-shrink: 0; }
.course-item strong { flex: 1; font-size: 14px; }
.tags-row { display: flex; gap: 6px; flex-shrink: 0; }
.t {
  background: #f0f0f0; color: #666;
  font-size: 11px; padding: 2px 8px;
  border-radius: 4px;
}

/* ========== 标准化项目 ========== */
.scale-bar {
  display: flex; align-items: stretch; gap: 0;
  margin-bottom: 48px;
  border-radius: var(--radius);
  overflow: hidden;
  border: 1px solid var(--border);
}
.scale-item {
  flex: 1; padding: 28px 24px; text-align: center;
  background: var(--white);
}
.scale-item:nth-child(3) { background: linear-gradient(135deg, var(--red), var(--red-dark)); color: var(--white); }
.scale-item:nth-child(3) .scale-range { color: rgba(255,255,255,0.8); }
.scale-item:nth-child(3) .scale-focus { color: var(--white); }
.scale-range { font-size: 13px; color: var(--text-light); margin-bottom: 10px; font-weight: 600; }
.scale-focus { font-size: 14px; line-height: 1.9; }
.scale-arrow { display: flex; align-items: center; padding: 0 8px; font-size: 22px; color: var(--border); border-top: 1px solid var(--border); border-bottom: 1px solid var(--border); background: var(--bg); }

.projects-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.project-card {
  background: var(--white);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px;
  transition: all 0.3s;
}
.project-card:hover { box-shadow: var(--shadow); transform: translateY(-4px); }
.project-card.featured { border-color: var(--red); }
.project-card h4 { font-size: 18px; font-weight: 700; margin-bottom: 4px; }
.project-sub { font-size: 12px; color: var(--red); font-weight: 600; margin-bottom: 12px; }
.project-card p { font-size: 13px; color: var(--text-light); margin-bottom: 16px; line-height: 1.7; }
.project-value { display: flex; flex-direction: column; gap: 6px; }
.project-value span { font-size: 12px; color: var(--text-light); }

/* ========== 合作案例 ========== */
.sub-title { font-size: 22px; font-weight: 700; margin-bottom: 28px; }
.cases-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 20px; }
.case-card {
  background: var(--white);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  transition: all 0.2s;
}
.case-card:hover { box-shadow: var(--shadow); }
.case-tag {
  display: inline-block;
  background: var(--red-light); color: var(--red);
  font-size: 11px; font-weight: 700;
  padding: 3px 10px; border-radius: 4px;
  margin-bottom: 10px;
}
.case-card h4 { font-size: 16px; font-weight: 700; margin-bottom: 10px; }
.case-need { font-size: 13px; color: var(--text-light); margin-bottom: 12px; line-height: 1.6; }
.case-result p { font-size: 13px; font-weight: 600; margin-bottom: 6px; }
.case-result ul { padding-left: 18px; }
.case-result ul li { font-size: 13px; color: var(--text-light); margin-bottom: 4px; }

.inst-cases { display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px; }
.inst-case {
  background: var(--white);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  text-align: center;
  transition: all 0.2s;
}
.inst-case:hover { box-shadow: var(--shadow); transform: translateY(-4px); }
.inst-icon { font-size: 36px; margin-bottom: 12px; }
.inst-case h4 { font-size: 15px; font-weight: 700; margin-bottom: 8px; }
.inst-case p { font-size: 13px; color: var(--text-light); line-height: 1.6; }

.scale-cards { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
.scale-card {
  background: var(--white);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px;
}
.scale-label {
  font-size: 14px; font-weight: 700; color: var(--red);
  margin-bottom: 8px; padding-bottom: 8px;
  border-bottom: 1px solid var(--border);
}
.scale-card p { font-size: 13px; color: var(--text-light); line-height: 1.7; }

/* ========== 讲师团队 ========== */
.team-features { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; margin-bottom: 40px; }
.team-feat {
  background: var(--white);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  text-align: center;
}
.feat-icon { font-size: 40px; margin-bottom: 14px; }
.team-feat h4 { font-size: 16px; font-weight: 700; margin-bottom: 8px; }
.team-feat p { font-size: 13px; color: var(--text-light); line-height: 1.6; }
.team-areas { display: flex; flex-wrap: wrap; gap: 10px; }
.area-tag {
  background: var(--red-light); color: var(--red);
  padding: 8px 20px; border-radius: 24px;
  font-size: 14px; font-weight: 600;
}

/* ========== 合作模式 ========== */
.coop-steps {
  display: flex; align-items: stretch;
  gap: 0; margin-bottom: 48px;
  flex-wrap: wrap;
}
.coop-step {
  flex: 1; min-width: 180px;
  background: var(--white);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px 20px;
  text-align: center;
}
.coop-arrow { display: flex; align-items: center; padding: 0 10px; font-size: 22px; color: #ccc; }
.step-num { font-size: 40px; font-weight: 800; color: var(--red-light); margin-bottom: 10px; }
.coop-step h4 { font-size: 17px; font-weight: 700; margin-bottom: 8px; }
.coop-step p { font-size: 13px; color: var(--text-light); }

.coop-promise {
  background: linear-gradient(135deg, #0a0a1a 0%, #1a0010 100%);
  border-radius: var(--radius);
  padding: 40px;
  color: var(--white);
}
.coop-promise h3 { font-size: 22px; font-weight: 700; margin-bottom: 24px; text-align: center; }
.promise-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
.promise-item { display: flex; gap: 12px; align-items: flex-start; }
.promise-item span { font-size: 18px; flex-shrink: 0; }
.promise-item p { font-size: 14px; color: rgba(255,255,255,0.8); }

/* ========== 联系我们 ========== */
.contact-content { display: grid; grid-template-columns: 1fr 1.5fr; gap: 48px; }
.contact-info { display: flex; flex-direction: column; gap: 24px; }
.contact-item { display: flex; gap: 16px; align-items: flex-start; }
.contact-icon { font-size: 28px; flex-shrink: 0; }
.contact-item strong { display: block; font-size: 14px; font-weight: 700; color: var(--text-light); margin-bottom: 4px; }
.contact-item p { font-size: 16px; font-weight: 600; }

.contact-form { background: var(--bg); border-radius: var(--radius); padding: 32px; }
.contact-form h3 { font-size: 20px; font-weight: 700; margin-bottom: 24px; }
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; margin-bottom: 12px; }
.contact-form input,
.contact-form select,
.contact-form textarea {
  width: 100%; padding: 12px 16px;
  border: 1px solid var(--border); border-radius: 8px;
  font-size: 14px; font-family: inherit;
  background: var(--white); color: var(--text);
  transition: border-color 0.2s;
  margin-bottom: 12px;
}
.contact-form input:focus,
.contact-form select:focus,
.contact-form textarea:focus {
  outline: none; border-color: var(--red);
}
.contact-form .btn-primary { width: 100%; font-size: 16px; }

/* ========== 页脚 ========== */
.footer { background: #0a0a1a; padding: 60px 0 0; }
.footer-inner { display: grid; grid-template-columns: 2fr 1fr 1.5fr; gap: 40px; padding-bottom: 40px; }
.footer-brand p { font-size: 13px; color: rgba(255,255,255,0.5); margin-top: 8px; }
.footer-links, .footer-contact { }
.footer-links h4, .footer-contact h4 { font-size: 14px; font-weight: 700; color: var(--white); margin-bottom: 16px; }
.footer-links a { display: block; font-size: 13px; color: rgba(255,255,255,0.5); text-decoration: none; margin-bottom: 8px; transition: color 0.2s; }
.footer-links a:hover { color: var(--white); }
.footer-contact p { font-size: 13px; color: rgba(255,255,255,0.5); margin-bottom: 8px; }
.footer-bottom {
  border-top: 1px solid rgba(255,255,255,0.1);
  padding: 20px 24px; text-align: center;
}
.footer-bottom p { font-size: 12px; color: rgba(255,255,255,0.3); }

/* ========== 响应式 ========== */
@media (max-width: 900px) {
  .about-grid { grid-template-columns: 1fr; }
  .projects-grid { grid-template-columns: 1fr; }
  .cases-grid { grid-template-columns: 1fr; }
  .team-features { grid-template-columns: repeat(2, 1fr); }
  .inst-cases { grid-template-columns: repeat(2, 1fr); }
  .scale-cards { grid-template-columns: 1fr; }
  .promise-grid { grid-template-columns: 1fr 1fr; }
  .contact-content { grid-template-columns: 1fr; }
  .footer-inner { grid-template-columns: 1fr 1fr; }
  .coop-arrow { display: none; }
  .scale-arrow { display: none; }
  .scale-bar { flex-direction: column; }
}

@media (max-width: 600px) {
  .nav-links { display: none; }
  .hero-stats { gap: 24px; }
  .delivery-grid { flex-direction: column; align-items: center; }
  .delivery-card { max-width: 100%; }
  .tab-nav { gap: 4px; }
  .tab-btn { padding: 8px 14px; font-size: 13px; }
  .team-features { grid-template-columns: 1fr; }
  .inst-cases { grid-template-columns: 1fr; }
  .promise-grid { grid-template-columns: 1fr; }
  .footer-inner { grid-template-columns: 1fr; }
  .form-row { grid-template-columns: 1fr; }
  .coop-steps { flex-direction: column; }
}