/* ===== Reset & Base ===== */
*, *::before, *::after { margin:0; padding:0; box-sizing:border-box; }
html { scroll-behavior:smooth; font-size:16px; }
body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  color: #1a1a2e; line-height: 1.6; background: #fff;
}
a { text-decoration:none; color:inherit; }
img { max-width:100%; display:block; }

/* ===== Colors ===== */
:root {
  --green-500: #07C160;
  --green-600: #06AD56;
  --green-50: #f0faf4;
  --green-100: #dcfce7;
  --dark: #1a1a2e;
  --gray-50: #f8f9fa;
  --gray-100: #f1f3f5;
  --gray-200: #e9ecef;
  --gray-400: #ced4da;
  --gray-500: #868e96;
  --gray-600: #495057;
  --gray-700: #343a40;
  --white: #ffffff;
  --shadow-sm: 0 1px 3px rgba(0,0,0,0.06);
  --shadow: 0 4px 12px rgba(0,0,0,0.08);
  --shadow-lg: 0 12px 40px rgba(0,0,0,0.12);
  --radius: 12px;
  --max-w: 1200px;
}

/* ===== Navbar ===== */
#navbar {
  position: fixed; top: 0; left: 0; right: 0; z-index: 100;
  background: rgba(255,255,255,0.92); backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--gray-200); height: 64px;
  transition: box-shadow 0.3s;
}
#navbar.scrolled { box-shadow: var(--shadow); }
.nav-inner { max-width: var(--max-w); margin: 0 auto; height: 100%; display: flex; align-items: center; justify-content: space-between; padding: 0 24px; }
.logo { font-size: 1.3rem; font-weight: 700; color: var(--green-500); }
.nav-links { display: flex; gap: 32px; align-items: center; list-style: none; }
.nav-links a { font-size: 0.95rem; color: var(--gray-600); transition: color 0.2s; font-weight: 500; }
.nav-links a:hover { color: var(--green-500); }
.btn-nav { background: var(--green-500); color: #fff !important; padding: 8px 20px; border-radius: 8px; font-weight: 600 !important; transition: background 0.2s; }
.btn-nav:hover { background: var(--green-600) !important; }
.mobile-menu-btn { display: none; background: none; border: none; font-size: 1.4rem; color: var(--dark); cursor: pointer; }

/* ===== Hero ===== */
#hero {
  padding: 120px 24px 80px; background: linear-gradient(160deg, var(--green-50) 0%, #fff 50%, var(--green-50) 100%);
  min-height: 90vh; display: flex; align-items: center;
}
.hero-inner { max-width: var(--max-w); margin: 0 auto; display: grid; grid-template-columns: 1fr 1fr; gap: 60px; align-items: center; }
.badge { display: inline-block; background: var(--green-100); color: var(--green-600); padding: 6px 16px; border-radius: 20px; font-size: 0.85rem; font-weight: 600; margin-bottom: 20px; }
#hero h1 { font-size: 2.8rem; font-weight: 800; line-height: 1.3; margin-bottom: 16px; color: var(--dark); }
.hl { color: var(--green-500); }
.hero-desc { font-size: 1.1rem; color: var(--gray-600); margin-bottom: 32px; line-height: 1.8; }
.hero-actions { display: flex; gap: 16px; margin-bottom: 40px; flex-wrap: wrap; }
.btn-primary { display: inline-flex; align-items: center; gap: 8px; background: var(--green-500); color: #fff; padding: 14px 32px; border-radius: 10px; font-size: 1rem; font-weight: 600; transition: all 0.2s; }
.btn-primary:hover { background: var(--green-600); transform: translateY(-1px); box-shadow: 0 4px 16px rgba(7,193,96,0.3); }
.btn-outline { display: inline-flex; align-items: center; gap: 8px; border: 2px solid var(--gray-200); color: var(--gray-600); padding: 14px 32px; border-radius: 10px; font-size: 1rem; font-weight: 600; transition: all 0.2s; }
.btn-outline:hover { border-color: var(--green-500); color: var(--green-500); }
.hero-stats { display: flex; gap: 40px; }
.stat { text-align: center; }
.stat-num { display: block; font-size: 1.6rem; font-weight: 800; color: var(--dark); }
.stat-label { font-size: 0.85rem; color: var(--gray-500); }
.hero-card {
  background: #fff; border-radius: 16px; padding: 36px; box-shadow: var(--shadow-lg);
  border: 1px solid var(--gray-100);
}
.card-icon { width: 56px; height: 56px; border-radius: 14px; background: var(--green-500); color: #fff; display: flex; align-items: center; justify-content: center; font-size: 1.5rem; margin-bottom: 20px; }
.card-title { font-size: 1.1rem; font-weight: 700; margin-bottom: 20px; color: var(--dark); }
.card-item { display: flex; align-items: center; gap: 10px; padding: 8px 0; color: var(--gray-600); font-size: 0.95rem; }
.card-item i { color: var(--green-500); font-size: 0.8rem; }

/* ===== Section Common ===== */
section { padding: 80px 24px; }
.section-inner { max-width: var(--max-w); margin: 0 auto; }
.section-header { text-align: center; margin-bottom: 48px; }
.section-tag { display: inline-block; background: var(--green-100); color: var(--green-600); padding: 4px 14px; border-radius: 16px; font-size: 0.8rem; font-weight: 600; margin-bottom: 12px; }
.section-header h2 { font-size: 2rem; font-weight: 800; color: var(--dark); margin-bottom: 12px; }
.section-desc { color: var(--gray-500); font-size: 1rem; max-width: 600px; margin: 0 auto; }

/* ===== Services ===== */
#services { background: var(--gray-50); }
.services-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.service-card {
  background: #fff; border-radius: var(--radius); padding: 32px; border: 1px solid var(--gray-100);
  transition: all 0.3s; cursor: default;
}
.service-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); border-color: var(--green-100); }
.highlight-card { border: 2px solid var(--green-500); background: linear-gradient(180deg, var(--green-50), #fff); }
.highlight-card .service-icon { background: var(--green-500); color: #fff; }
.service-icon { width: 48px; height: 48px; border-radius: 12px; background: var(--green-50); color: var(--green-500); display: flex; align-items: center; justify-content: center; font-size: 1.2rem; margin-bottom: 16px; }
.service-card h3 { font-size: 1.1rem; font-weight: 700; margin-bottom: 8px; color: var(--dark); }
.service-card p { font-size: 0.9rem; color: var(--gray-500); margin-bottom: 16px; line-height: 1.7; }
.service-tags { display: flex; flex-wrap: wrap; gap: 6px; }
.service-tags span { background: var(--green-50); color: var(--green-600); padding: 3px 10px; border-radius: 6px; font-size: 0.75rem; font-weight: 500; }

/* ===== Courses ===== */
.course-tabs { display: flex; justify-content: center; gap: 8px; margin-bottom: 32px; flex-wrap: wrap; }
.course-tab {
  padding: 10px 24px; border-radius: 8px; border: 1px solid var(--gray-200);
  background: #fff; color: var(--gray-600); font-size: 0.9rem; font-weight: 600;
  cursor: pointer; transition: all 0.2s;
}
.course-tab:hover { border-color: var(--green-500); color: var(--green-500); }
.course-tab.active { background: var(--green-500); color: #fff; border-color: var(--green-500); }
.course-panel { display: none; }
.course-panel.active { display: block; }
.course-tags-filter { display: flex; gap: 8px; margin-bottom: 20px; flex-wrap: wrap; }
.ctag {
  padding: 5px 14px; border-radius: 6px; font-size: 0.8rem; color: var(--gray-500);
  cursor: pointer; transition: all 0.2s; font-weight: 500;
}
.ctag:hover, .ctag.active { background: var(--green-50); color: var(--green-600); }
.course-list { display: grid; grid-template-columns: repeat(2, 1fr); gap: 12px; }
.course-item {
  display: flex; align-items: center; gap: 12px; padding: 16px 20px;
  background: #fff; border: 1px solid var(--gray-100); border-radius: 10px;
  transition: all 0.2s; cursor: pointer;
}
.course-item:hover { border-color: var(--green-500); box-shadow: var(--shadow-sm); transform: translateX(4px); }
.ci-cat { flex-shrink: 0; background: var(--green-50); color: var(--green-600); padding: 3px 10px; border-radius: 6px; font-size: 0.75rem; font-weight: 600; white-space: nowrap; }
.ci-title { flex: 1; font-size: 0.9rem; color: var(--dark); font-weight: 500; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.ci-arrow { color: var(--gray-400); font-size: 0.8rem; transition: transform 0.2s; }
.course-item:hover .ci-arrow { transform: translateX(4px); color: var(--green-500); }

/* ===== Articles ===== */
#articles { background: var(--gray-50); }
#articles-list { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; margin-bottom: 24px; }
.article-card {
  background: #fff; border-radius: var(--radius); overflow: hidden;
  border: 1px solid var(--gray-100); transition: all 0.3s; cursor: pointer;
}
.article-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); }
.article-cover { width: 100%; height: 180px; background: linear-gradient(135deg, var(--green-50), var(--green-100)); display: flex; align-items: center; justify-content: center; color: var(--green-500); font-size: 2.5rem; }
.article-body { padding: 20px; }
.article-meta { display: flex; gap: 12px; margin-bottom: 8px; }
.article-date { font-size: 0.8rem; color: var(--gray-400); }
.article-tag { font-size: 0.75rem; color: var(--green-600); background: var(--green-50); padding: 2px 8px; border-radius: 4px; }
.article-card h3 { font-size: 1rem; font-weight: 700; margin-bottom: 8px; color: var(--dark); display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden; }
.article-card p { font-size: 0.85rem; color: var(--gray-500); line-height: 1.6; display: -webkit-box; -webkit-line-clamp: 3; -webkit-box-orient: vertical; overflow: hidden; }
.no-articles { text-align: center; padding: 60px 20px; color: var(--gray-400); }
.no-articles i { font-size: 2.5rem; margin-bottom: 12px; display: block; }
.no-articles p { font-size: 1rem; }

/* ===== Modal ===== */
.modal { position: fixed; inset: 0; z-index: 200; display: none; align-items: center; justify-content: center; }
.modal.show { display: flex; }
.modal-overlay { position: absolute; inset: 0; background: rgba(0,0,0,0.5); }
.modal-content {
  position: relative; background: #fff; border-radius: 16px; max-width: 760px; width: 92%;
  max-height: 85vh; overflow-y: auto; padding: 40px; margin: 20px;
  box-shadow: var(--shadow-lg);
}
.modal-close { position: absolute; top: 16px; right: 16px; background: var(--gray-100); border: none; width: 36px; height: 36px; border-radius: 50%; cursor: pointer; font-size: 1rem; color: var(--gray-600); transition: all 0.2s; }
.modal-close:hover { background: var(--gray-200); }
#article-modal-body h1 { font-size: 1.6rem; font-weight: 800; margin-bottom: 16px; color: var(--dark); }
#article-modal-body .meta { color: var(--gray-400); font-size: 0.85rem; margin-bottom: 24px; padding-bottom: 16px; border-bottom: 1px solid var(--gray-100); }
#article-modal-body .content { font-size: 0.95rem; color: var(--gray-700); line-height: 2; }
#article-modal-body .content p { margin-bottom: 16px; }
#article-modal-body .content h2 { font-size: 1.2rem; font-weight: 700; margin: 24px 0 12px; color: var(--dark); }
#article-modal-body .content img { border-radius: 8px; margin: 16px 0; }
#article-modal-body .content strong { color: var(--dark); }

/* ===== About ===== */
.about-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 60px; align-items: center; }
.about-text p { color: var(--gray-600); margin-bottom: 16px; line-height: 1.8; font-size: 0.95rem; }
.about-certs { display: flex; gap: 16px; margin-top: 24px; flex-wrap: wrap; }
.cert-badge { display: flex; align-items: center; gap: 8px; background: var(--green-50); color: var(--green-600); padding: 10px 18px; border-radius: 8px; font-size: 0.85rem; font-weight: 600; }
.about-card {
  background: linear-gradient(135deg, var(--green-500), var(--green-600)); border-radius: 16px;
  padding: 36px; color: #fff;
}
.about-card-title { font-size: 1.2rem; font-weight: 700; margin-bottom: 24px; }
.about-feature { display: flex; align-items: center; gap: 10px; padding: 8px 0; font-size: 0.95rem; }
.about-feature i { font-size: 0.9rem; opacity: 0.8; }

/* ===== Contact ===== */
#contact { background: var(--gray-50); }
.contact-box {
  background: linear-gradient(135deg, #1a1a2e, #2d2d44); border-radius: 20px;
  padding: 60px; display: flex; align-items: center; gap: 60px; color: #fff;
}
.contact-info h2 { font-size: 1.8rem; font-weight: 800; margin-bottom: 12px; }
.contact-info > p { color: rgba(255,255,255,0.7); margin-bottom: 32px; }
.contact-features { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
.cf-item { display: flex; align-items: center; gap: 10px; font-size: 0.9rem; color: rgba(255,255,255,0.85); }
.cf-item i { color: var(--green-500); font-size: 1rem; }
.contact-qr { flex-shrink: 0; text-align: center; }
.qr-img { width: 180px; height: 180px; border-radius: 12px; object-fit: contain; }
.qr-img.small { width: 120px; height: 120px; border-radius: 8px; }
.qr-label { margin-top: 12px; font-size: 0.9rem; color: rgba(255,255,255,0.7); }

/* ===== Footer ===== */
footer { background: var(--dark); color: rgba(255,255,255,0.6); padding: 40px 24px; }
.footer-inner { max-width: var(--max-w); margin: 0 auto; }
.footer-logo { font-size: 1.2rem; font-weight: 700; color: #fff; margin-bottom: 8px; }
.footer-brand p { font-size: 0.85rem; margin-bottom: 4px; }
.footer-links { display: flex; gap: 24px; margin: 20px 0; }
.footer-links a { font-size: 0.85rem; color: rgba(255,255,255,0.5); transition: color 0.2s; }
.footer-links a:hover { color: var(--green-500); }
.footer-copy { border-top: 1px solid rgba(255,255,255,0.1); padding-top: 20px; margin-top: 20px; }
.footer-copy p { font-size: 0.8rem; }

/* ===== Float QR ===== */
.float-qr {
  position: fixed; bottom: 32px; right: 32px; z-index: 90;
  width: 56px; height: 56px; background: var(--green-500); border-radius: 50%;
  display: flex; align-items: center; justify-content: center;
  color: #fff; font-size: 1.5rem; cursor: pointer;
  box-shadow: 0 4px 16px rgba(7,193,96,0.4); transition: all 0.3s;
}
.float-qr:hover { transform: scale(1.1); }
.float-qr-popup {
  position: absolute; bottom: 68px; right: 0;
  background: #fff; border-radius: 12px; padding: 16px; box-shadow: var(--shadow-lg);
  text-align: center; display: none; min-width: 160px;
}
.float-qr-popup p { font-size: 0.8rem; color: var(--gray-600); margin-bottom: 8px; }
.float-qr-popup.show { display: block; }

/* ===== Responsive ===== */
@media (max-width: 768px) {
  .nav-links { display: none; }
  .nav-links.open { display: flex; flex-direction: column; position: absolute; top: 64px; left: 0; right: 0; background: #fff; padding: 16px 24px; border-bottom: 1px solid var(--gray-200); gap: 16px; }
  .mobile-menu-btn { display: block; }
  .hero-inner { grid-template-columns: 1fr; gap: 40px; }
  #hero h1 { font-size: 2rem; }
  .services-grid { grid-template-columns: 1fr; }
  .course-list { grid-template-columns: 1fr; }
  #articles-list { grid-template-columns: 1fr; }
  .about-grid { grid-template-columns: 1fr; gap: 32px; }
  .contact-box { flex-direction: column; padding: 32px 24px; gap: 32px; }
  .contact-features { grid-template-columns: 1fr; }
  .hero-stats { gap: 24px; }
}