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

:root {
  --primary: #3b82f6 !important;
  --primary-dark: #2563eb !important;
  --accent: #10b981 !important;
  --accent-dark: #059669 !important;
  --danger: #ef4444 !important;
  --bg: #ffffff !important;
  --bg2: #f9fafb !important;
  --bg3: #f3f4f6 !important;
  --text: #111827 !important;
  --text-muted: #6b7280 !important;
  --border: #e5e7eb !important;
  --radius: 12px !important;
}

/* 强制覆盖所有样式 */
body {
  background: var(--bg) !important;
  color: var(--text) !important;
}

.hero h1 .highlight-text {
  color: var(--accent);
}

.stat-num {
  color: var(--accent) !important;
}

.btn-primary {
  background: var(--primary) !important;
  color: #fff !important;
}

.btn-primary:hover {
  background: var(--primary-dark) !important;
}

.price-ours {
  color: var(--accent) !important;
}

.calc-result-num {
  color: var(--accent) !important;
}

.model-card .m-icon svg {
  stroke: var(--accent) !important;
}

.feature-card:hover {
  border-color: var(--accent) !important;
}

.feature-icon svg {
  stroke: var(--accent) !important;
}

html { scroll-behavior: smooth; }

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Microsoft YaHei', sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
}

a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }

/* ── 导航 ── */
nav {
  position: sticky; top: 0; z-index: 100;
  background: rgba(255,255,255,0.92);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
  padding: 0 24px;
}
.nav-inner {
  max-width: 1440px; margin: 0 auto;
  display: flex; align-items: center; justify-content: space-between;
  height: 60px;
}
.nav-logo { font-size: 1.25rem; font-weight: 700; color: var(--text); }
.nav-logo span { color: var(--accent); }
.nav-links { display: flex; gap: 24px; align-items: center; }
.nav-links a { color: var(--text-muted); font-size: 0.9rem; }
.nav-links a:hover { color: var(--text); text-decoration: none; }
.nav-cta {
  background: var(--primary); color: #fff !important;
  padding: 8px 20px; border-radius: 8px; font-weight: 600;
  transition: background 0.2s;
}
.nav-cta:hover { background: var(--primary-dark); text-decoration: none !important; }

/* 移动端菜单 */
.mobile-menu-btn {
  display: none;
  cursor: pointer;
  color: var(--text);
  z-index: 101;
}

.mobile-menu {
  position: fixed;
  top: 60px;
  left: 0;
  width: 100%;
  background: var(--bg);
  border-top: 1px solid var(--border);
  box-shadow: 0 4px 12px rgba(0,0,0,0.1);
  padding: 20px 0;
  transform: translateY(-100%);
  opacity: 0;
  visibility: hidden;
  transition: all 0.3s ease;
  z-index: 99;
}

.mobile-menu.active {
  transform: translateY(0);
  opacity: 1;
  visibility: visible;
}

.mobile-menu a {
  display: block;
  padding: 12px 24px;
  color: var(--text-muted);
  font-size: 1rem;
  border-bottom: 1px solid var(--border);
  transition: all 0.2s;
}

.mobile-menu a:hover {
  background: var(--bg2);
  color: var(--primary);
  text-decoration: none;
}

.mobile-menu .nav-cta {
  display: inline-block;
  margin: 16px 24px;
  border: none;
}

/* 导航下拉菜单 */
.nav-dropdown {
  position: relative;
  display: inline-block;
}
.dropdown-toggle {
  position: relative;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 4px;
}
.dropdown-toggle::after {
  content: '▼';
  font-size: 0.7rem;
  color: var(--text-muted);
  transition: transform 0.3s;
}
.nav-dropdown:hover .dropdown-toggle::after {
  transform: rotate(180deg);
}
.dropdown-menu {
  position: absolute;
  top: 100%;
  left: 0;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 8px;
  box-shadow: 0 4px 12px rgba(0,0,0,0.1);
  padding: 8px 0;
  min-width: 160px;
  z-index: 101;
  opacity: 0;
  visibility: hidden;
  transform: translateY(-10px);
  transition: all 0.3s ease;
}
.nav-dropdown:hover .dropdown-menu {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}
.dropdown-menu a {
  display: block;
  padding: 10px 16px;
  color: var(--text-muted);
  font-size: 0.85rem;
  transition: all 0.2s;
}
.dropdown-menu a:hover {
  background: var(--bg2);
  color: var(--primary);
  text-decoration: none;
}

/* ── 通用容器 ── */
.container { max-width: 1440px; margin: 0 auto; padding: 0 24px; }
section { padding: 80px 0; }

/* ── Hero ── */
.hero {
  padding: 160px 0 100px;
  background: radial-gradient(ellipse 60% 40% at 50% 30%, rgba(59,130,246,0.08) 0%, transparent 70%);
  text-align: center;
}
.hero-badge {
  display: inline-block;
  background: rgba(59,130,246,0.15);
  border: 1px solid rgba(59,130,246,0.4);
  color: var(--primary);
  padding: 6px 16px; border-radius: 999px; font-size: 0.9rem;
  margin-bottom: 32px;
}
.hero-title {
  font-size: clamp(2rem, 5vw, 3.5rem);
  font-weight: 800; 
  line-height: 1.2;
  margin-bottom: 28px;
  max-width: 800px;
  margin-left: auto;
  margin-right: auto;
  display: block;
}
.hero-title-main {
  display: block;
  font-size: 1em;
  margin-bottom: 8px;
}
.hero-title-sub {
  display: block;
  font-size: 0.8em;
  font-weight: 600;
}
.hero-title-sub .brand {
  font-size: 0.7em;
  font-weight: 500;
  color: var(--primary);
  margin-right: 8px;
}
.hero h1 .red { color: #f87171; }
.hero-sub {
  font-size: 1.2rem; color: var(--text-muted);
  max-width: 650px; margin: 0 auto 48px;
  line-height: 1.6;
}
.hero-sub strong { color: var(--text); }
.hero-btns { display: flex; gap: 24px; justify-content: center; flex-wrap: wrap; margin-bottom: 72px; }
.btn-primary {
  display: inline-flex; align-items: center; gap: 8px;
  background: var(--primary); color: #fff;
  padding: 14px 32px; border-radius: 10px; font-size: 1rem; font-weight: 600;
  transition: background 0.2s, transform 0.1s;
}
.btn-primary:hover { background: var(--primary-dark); transform: translateY(-1px); text-decoration: none; }
.btn-secondary {
  display: inline-flex; align-items: center; gap: 8px;
  background: transparent; color: var(--text);
  border: 1px solid var(--border);
  padding: 14px 32px; border-radius: 10px; font-size: 1rem; font-weight: 500;
  transition: border-color 0.2s, background 0.2s;
}
.btn-secondary:hover { border-color: var(--primary); background: rgba(249,115,22,0.1); text-decoration: none; }

/* 数字统计 */
.hero-stats {
  margin-top: 60px;
  background: var(--bg);
  border-radius: var(--radius);
  padding: 40px;
  box-shadow: 0 4px 20px rgba(0,0,0,0.05);
  max-width: 1200px;
  margin-left: auto;
  margin-right: auto;
}
.stat-row {
  display: flex; 
  justify-content: space-between; 
  gap: 24px; 
  flex-wrap: wrap;
}
.stat { 
  text-align: center; 
  flex: 1;
  min-width: 150px;
  display: flex;
  flex-direction: column;
  align-items: center;
}
.stat-icon {
  width: 48px;
  height: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(16,185,129,0.1);
  border-radius: 50%;
  margin-bottom: 16px;
}
.stat-icon svg {
  width: 24px;
  height: 24px;
  stroke: var(--accent);
  stroke-width: 2;
  fill: none;
}
.stat-num { 
  font-size: 2rem; 
  font-weight: 800; 
  color: var(--accent); 
  margin-bottom: 8px;
}
.stat-label { 
  font-size: 0.85rem; 
  color: var(--text-muted); 
  line-height: 1.4;
  text-align: center;
}

/* ── 痛点区 ── */
.pain { 
  background: var(--bg2); 
  padding: 100px 0;
}
.pain h2 { 
  font-size: 2rem; 
  font-weight: 700; 
  text-align: center; 
  margin-bottom: 16px;
  max-width: 700px;
  margin-left: auto;
  margin-right: auto;
}
.pain-sub { 
  text-align: center; 
  color: var(--text-muted); 
  margin-bottom: 64px;
  font-size: 1.1rem;
  max-width: 600px;
  margin-left: auto;
  margin-right: auto;
}
.pain-cards {
  display: grid; 
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); 
  gap: 32px;
  max-width: 1000px;
  margin-left: auto;
  margin-right: auto;
}
.pain-card {
  background: var(--bg); 
  border-radius: var(--radius);
  padding: 36px;
  border-left: 4px solid var(--primary);
  box-shadow: 0 4px 12px rgba(0,0,0,0.05);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}
.pain-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 8px 20px rgba(0,0,0,0.1);
}
.pain-card .icon {
  width: 56px; 
  height: 56px;
  display: flex; 
  align-items: center; 
  justify-content: center;
  margin-bottom: 20px;
  background: rgba(16,185,129,0.1);
  border-radius: 50%;
}
.pain-card .icon svg {
  width: 28px; 
  height: 28px;
  stroke: var(--accent);
  stroke-width: 2;
  fill: none;
}
.pain-card h3 { 
  font-size: 1.2rem; 
  margin-bottom: 12px;
  font-weight: 600;
}
.pain-card p { 
  color: var(--text-muted); 
  font-size: 0.95rem; 
  line-height: 1.7; 
  margin-bottom: 16px;
}
.pain-solution {
  background: rgba(16,185,129,0.1);
  border: 1px solid rgba(16,185,129,0.3);
  border-radius: 8px;
  padding: 16px;
  font-size: 0.9rem;
  margin-top: 16px;
}
.pain-solution strong { color: var(--accent); }

/* ── 价格对比表 ── */
#price {
  padding: 100px 0;
  background: var(--bg);
}
#price h2 { 
  font-size: 2rem; 
  font-weight: 700; 
  text-align: center; 
  margin-bottom: 16px;
  max-width: 700px;
  margin-left: auto;
  margin-right: auto;
}
.section-sub { 
  text-align: center; 
  color: var(--text-muted); 
  margin-bottom: 64px;
  font-size: 1.1rem;
  max-width: 600px;
  margin-left: auto;
  margin-right: auto;
}
.price-info {
  margin-bottom: 48px;
}
.table-wrap { 
  overflow-x: auto; 
  border-radius: var(--radius); 
  border: 1px solid var(--border);
  box-shadow: 0 4px 12px rgba(0,0,0,0.05);
  margin-bottom: 32px;
}
table { width: 100%; border-collapse: collapse; min-width: 700px; }
thead { background: var(--bg3); }
thead th {
  padding: 16px 24px; 
  text-align: left; 
  font-size: 0.9rem;
  color: var(--text-muted); 
  text-transform: uppercase; 
  letter-spacing: 0.05em;
}
tbody tr { border-top: 1px solid var(--border); }
tbody tr:hover { background: rgba(249,250,251,0.8); }
tbody td { padding: 20px 24px; font-size: 1rem; }
.tag-model { font-weight: 600; }
.price-official { color: var(--text-muted); text-decoration: line-through; }
.price-ours { color: var(--accent); font-weight: 700; font-size: 1.1rem; }
.save-badge {
  display: inline-block;
  background: rgba(16,185,129,0.15); 
  color: var(--accent);
  border: 1px solid rgba(16,185,129,0.3);
  padding: 4px 12px; 
  border-radius: 999px; 
  font-size: 0.85rem; 
  font-weight: 600;
}
.table-note { margin-top: 16px; font-size: 0.85rem; color: var(--text-muted); text-align: center; }
.price-summary {
  background: var(--bg2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 32px;
  margin-top: 48px;
  text-align: center;
  box-shadow: 0 4px 12px rgba(0,0,0,0.05);
}
.price-summary h3 {
  font-size: 1.2rem;
  font-weight: 700;
  margin-bottom: 16px;
  color: var(--text);
}
.price-summary p {
  color: var(--text-muted);
  line-height: 1.6;
  font-size: 1rem;
}

/* 价格对比表格按钮 */
.btn-view-details {
  background: var(--primary);
  color: #fff;
  border: none;
  padding: 6px 12px;
  border-radius: 6px;
  font-size: 0.85rem;
  cursor: pointer;
  transition: background 0.2s, transform 0.1s;
}
.btn-view-details:hover {
  background: var(--primary-dark);
  transform: translateY(-1px);
}

/* 模型详情弹窗 */
.modal {
  display: none;
  position: fixed;
  z-index: 1000;
  left: 0;
  top: 0;
  width: 100%;
  height: 100%;
  overflow: auto;
  background-color: rgba(0,0,0,0.5);
}
.modal-content {
  background-color: var(--bg);
  padding: 32px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  width: 80%;
  max-width: 600px;
  box-shadow: 0 10px 25px rgba(0,0,0,0.2);
}

/* 为使用flexbox的modal添加特定样式 */
.modal[style*="flex"] .modal-content {
  margin: 0;
  width: auto;
}
.modal-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 24px;
}
.modal-title {
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--text);
}
.close {
  color: var(--text-muted);
  font-size: 24px;
  font-weight: bold;
  cursor: pointer;
}
.close:hover {
  color: var(--text);
}
.modal-body {
  line-height: 1.6;
}
.modal-body h4 {
  margin-top: 20px;
  margin-bottom: 12px;
  color: var(--text);
  font-size: 1rem;
}
.modal-body p {
  color: var(--text-muted);
  margin-bottom: 12px;
}
.modal-body ul {
  margin-left: 20px;
  margin-bottom: 16px;
}
.modal-body li {
  color: var(--text-muted);
  margin-bottom: 8px;
}

/* 跳转提示弹窗 */
.redirect-modal {
  display: none;
  position: fixed;
  z-index: 1000;
  left: 0;
  top: 0;
  width: 100%;
  height: 100%;
  overflow: auto;
  background-color: rgba(0,0,0,0.5);
}
.redirect-content {
  background-color: var(--bg);
  margin: 20% auto;
  padding: 32px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  width: 80%;
  max-width: 500px;
  box-shadow: 0 10px 25px rgba(0,0,0,0.2);
  text-align: center;
}
.redirect-content h3 {
  margin-bottom: 16px;
  color: var(--text);
}
.redirect-content p {
  margin-bottom: 24px;
  color: var(--text-muted);
}
.redirect-buttons {
  display: flex;
  gap: 16px;
  justify-content: center;
}
.redirect-btn {
  padding: 10px 24px;
  border-radius: 8px;
  font-size: 0.95rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s;
  border: none;
}
.redirect-btn-primary {
  background: var(--primary);
  color: #fff;
}
.redirect-btn-primary:hover {
  background: var(--primary-dark);
  transform: translateY(-2px);
}
.redirect-btn-secondary {
  background: transparent;
  color: var(--text);
  border: 1px solid var(--border);
}
.redirect-btn-secondary:hover {
  border-color: var(--primary);
  background: rgba(59,130,246,0.1);
  transform: translateY(-2px);
}

.price-info {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
  margin-bottom: 32px;
}
.price-highlight, .price-discount {
  background: var(--bg2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
}
.price-highlight-title, .discount-title {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: 16px;
  color: var(--text);
}
.price-highlight-content {
  display: flex;
  align-items: center;
  justify-content: space-around;
  gap: 16px;
}
.price-item {
  text-align: center;
  flex: 1;
}
.price-label {
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-bottom: 8px;
}
.price-value {
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--primary);
}
.price-divider {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--accent);
  padding: 0 16px;
}
.discount-content p {
  margin-bottom: 8px;
  line-height: 1.6;
}
.discount-content strong {
  color: var(--primary);
  font-weight: 700;
}
.discount-note {
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-top: 12px;
}

/* ── 计算器 ── */
.calculator { 
  background: var(--bg2);
  padding: 100px 0;
}
.calculator h2 { 
  font-size: 2rem; 
  font-weight: 700; 
  text-align: center; 
  margin-bottom: 16px;
  max-width: 700px;
  margin-left: auto;
  margin-right: auto;
}
.calc-box {
  max-width: 720px; 
  margin: 0 auto;
  background: var(--bg); 
  border-radius: var(--radius);
  padding: 48px;
  border: 1px solid var(--border);
  box-shadow: 0 4px 12px rgba(0,0,0,0.05);
  margin-top: 48px;
}
.calc-row { margin-bottom: 32px; }
.calc-row label {
  display: block; 
  font-size: 1rem; 
  color: var(--text-muted); 
  margin-bottom: 12px;
  font-weight: 500;
}
.calc-row select, .calc-row input {
  width: 100%; 
  background: var(--bg2); 
  border: 1px solid var(--border);
  color: var(--text); 
  padding: 16px 20px; 
  border-radius: 10px; 
  font-size: 1.1rem;
  outline: none; 
  transition: border-color 0.2s, box-shadow 0.2s;
}
.calc-row select:focus, .calc-row input:focus { 
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(59,130,246,0.1);
}
.calc-result {
  background: rgba(16,185,129,0.1); 
  border: 1px solid rgba(16,185,129,0.3);
  border-radius: 12px; 
  padding: 32px; 
  text-align: center; 
  margin-top: 16px;
}
.calc-result-num { 
  font-size: 3rem; 
  font-weight: 800; 
  color: var(--accent); 
  margin-bottom: 8px;
}
.calc-result-label { 
  font-size: 1rem; 
  color: var(--text-muted); 
  margin-bottom: 24px;
}
.calc-detail {
  display: flex; 
  justify-content: space-around; 
  margin-top: 24px;
  flex-wrap: wrap; 
  gap: 20px;
  padding-top: 24px;
  border-top: 1px solid var(--border);
}
.calc-item { text-align: center; }
.calc-item-val { 
  font-weight: 700; 
  font-size: 1.2rem;
  margin-bottom: 4px;
}
.calc-item-label { 
  font-size: 0.9rem; 
  color: var(--text-muted); 
}
.calc-tip {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
  margin-top: 24px;
  padding: 16px;
  background: rgba(59,130,246,0.1);
  border: 1px solid rgba(59,130,246,0.3);
  border-radius: 10px;
  font-size: 0.95rem;
  color: var(--primary);
}
.calc-tip svg {
  width: 20px;
  height: 20px;
  stroke: var(--primary);
  stroke-width: 2;
  fill: none;
}
.calc-examples {
  margin-top: 64px;
  text-align: center;
}
.calc-examples h3 {
  font-size: 1.3rem;
  font-weight: 700;
  margin-bottom: 32px;
  color: var(--text);
}
.calc-example-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 24px;
  max-width: 720px;
  margin: 0 auto;
}
.calc-example-item {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 32px;
  text-align: center;
  transition: all 0.3s ease;
  box-shadow: 0 4px 12px rgba(0,0,0,0.05);
}
.calc-example-item:hover {
  border-color: var(--primary);
  transform: translateY(-4px);
  box-shadow: 0 8px 20px rgba(0,0,0,0.1);
}
.example-amount {
  font-size: 1.6rem;
  font-weight: 700;
  color: var(--text);
  margin-bottom: 12px;
}
.example-save {
  font-size: 1.2rem;
  font-weight: 600;
  color: var(--accent);
  margin-bottom: 16px;
}
.example-desc {
  font-size: 0.9rem;
  color: var(--text-muted);
  line-height: 1.5;
}

/* ── 模型支持 ── */
#models {
  padding: 100px 0;
  background: var(--bg2);
}
#models h2 { 
  font-size: 2rem; 
  font-weight: 700; 
  text-align: center; 
  margin-bottom: 16px;
  max-width: 700px;
  margin-left: auto;
  margin-right: auto;
}
#models .section-sub {
  text-align: center; 
  color: var(--text-muted); 
  margin-bottom: 64px;
  font-size: 1.1rem;
  max-width: 600px;
  margin-left: auto;
  margin-right: auto;
}
.model-tabs {
  display: flex;
  justify-content: center;
  gap: 16px;
  flex-wrap: wrap;
  margin-bottom: 48px;
}
.model-tab {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 24px;
  padding: 10px 20px;
  font-size: 0.95rem;
  cursor: pointer;
  transition: all 0.3s ease;
  color: var(--text-muted);
  font-weight: 500;
}
.model-tab:hover {
  border-color: var(--primary);
  color: var(--primary);
  transform: translateY(-2px);
}
.model-tab.active {
  background: var(--primary);
  color: #fff;
  border-color: var(--primary);
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(59,130,246,0.3);
}
.model-grid {
  display: grid; 
  grid-template-columns: repeat(5, 1fr); 
  gap: 20px;
  max-width: 1200px;
  margin-left: auto;
  margin-right: auto;
}
.model-card {
  background: var(--bg); 
  border: 1px solid var(--border);
  border-radius: var(--radius); 
  padding: 24px 16px; 
  text-align: center;
  transition: all 0.3s ease;
  position: relative;
  cursor: pointer;
  box-shadow: 0 4px 12px rgba(0,0,0,0.05);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  min-height: 180px;
}
.model-card:hover { 
  border-color: var(--primary); 
  transform: translateY(-4px);
  box-shadow: 0 8px 20px rgba(0,0,0,0.1);
}
.model-card .m-icon {
  width: 48px; 
  height: 48px;
  display: flex; 
  align-items: center; 
  justify-content: center;
  margin-bottom: 16px;
  background: rgba(16,185,129,0.1);
  border-radius: 50%;
}
.model-card .m-icon svg {
  width: 24px; 
  height: 24px;
  stroke: var(--accent);
  stroke-width: 2;
  fill: none;
}
.model-card .m-name { 
  font-size: 0.9rem; 
  font-weight: 600;
  margin-bottom: 8px;
  text-align: center;
}
.model-card .m-sub { 
  font-size: 0.8rem; 
  color: var(--text-muted); 
  text-align: center;
}

/* ── 优势 ── */
.features { 
  background: var(--bg);
  padding: 100px 0;
}
.features h2 { 
  font-size: 2rem; 
  font-weight: 700; 
  text-align: center; 
  margin-bottom: 16px;
  max-width: 700px;
  margin-left: auto;
  margin-right: auto;
}
.features .section-sub {
  text-align: center; 
  color: var(--text-muted); 
  margin-bottom: 64px;
  font-size: 1.1rem;
  max-width: 600px;
  margin-left: auto;
  margin-right: auto;
}
.feature-grid {
  display: grid; 
  grid-template-columns: repeat(2, 1fr); 
  gap: 32px;
  max-width: 1000px;
  margin-left: auto;
  margin-right: auto;
}
.feature-card {
  background: var(--bg2); 
  border-radius: var(--radius);
  padding: 40px 32px; 
  border: 1px solid var(--border);
  transition: all 0.3s ease;
  box-shadow: 0 4px 12px rgba(0,0,0,0.05);
}
.feature-card:hover { 
  border-color: var(--accent);
  transform: translateY(-4px);
  box-shadow: 0 8px 20px rgba(0,0,0,0.1);
}
.feature-icon {
  width: 56px; 
  height: 56px;
  display: flex; 
  align-items: center; 
  justify-content: center;
  margin-bottom: 24px;
  background: rgba(16,185,129,0.1);
  border-radius: 50%;
}
.feature-icon svg {
  width: 28px; 
  height: 28px;
  stroke: var(--accent);
  stroke-width: 2;
  fill: none;
}
.feature-card h3 { 
  font-size: 1.2rem; 
  margin-bottom: 16px;
  font-weight: 600;
}
.feature-card p { 
  color: var(--text-muted); 
  font-size: 0.95rem; 
  line-height: 1.7;
}

/* ── 文章列表 ── */
.articles { 
  background: var(--bg2);
  padding: 100px 0;
}
.section-header {
  text-align: center;
  margin-bottom: 64px;
}
.section-header h2 {
  font-size: 2rem;
  font-weight: 700;
  margin-bottom: 16px;
  color: var(--text);
  max-width: 700px;
  margin-left: auto;
  margin-right: auto;
}
.section-header p {
  color: var(--text-muted);
  font-size: 1.1rem;
  max-width: 600px;
  margin-left: auto;
  margin-right: auto;
}
.article-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 32px;
  margin-bottom: 48px;
  max-width: 1000px;
  margin-left: auto;
  margin-right: auto;
}
.article-item {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  transition: all 0.3s ease;
  display: block;
  text-decoration: none;
  color: var(--text);
  box-shadow: 0 4px 12px rgba(0,0,0,0.05);
}
.article-item:hover {
  border-color: var(--primary);
  transform: translateY(-6px);
  box-shadow: 0 12px 24px rgba(0,0,0,0.1);
  text-decoration: none;
}
.article-image {
  width: 100%;
  height: 200px;
  overflow: hidden;
}
.article-image a {
  display: block;
}
.article-image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.5s ease;
}
.article-item:hover .article-image img {
  transform: scale(1.1);
}
.article-content {
  padding: 24px;
}
.article-meta {
  display: flex;
  gap: 16px;
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-bottom: 16px;
}
.article-meta span {
  display: flex;
  align-items: center;
  gap: 6px;
}
.article-title {
  font-size: 1.1rem;
  font-weight: 600;
  margin-bottom: 16px;
  line-height: 1.4;
  color: var(--text);
  text-decoration: none;
  transition: color 0.2s;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}
.article-item:hover .article-title {
  color: var(--primary);
}
.article-intro {
  color: var(--text-muted);
  font-size: 0.9rem;
  line-height: 1.6;
  margin-bottom: 20px;
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
}
.article-footer {
  margin-top: 16px;
}
.read-more {
  color: var(--primary);
  font-size: 0.9rem;
  font-weight: 600;
  text-decoration: none;
  transition: all 0.3s ease;
  display: inline-flex;
  align-items: center;
  gap: 6px;
}
.read-more:hover {
  color: var(--primary-dark);
  text-decoration: none;
  transform: translateX(4px);
}
.article-more {
  text-align: center;
  margin-top: 48px;
}
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 10px 24px;
  border-radius: 8px;
  font-size: 0.95rem;
  font-weight: 600;
  transition: all 0.2s;
  text-decoration: none;
}
.btn-primary {
  background: var(--primary);
  color: #fff;
}
.btn-primary:hover {
  background: var(--primary-dark);
  transform: translateY(-2px);
}
.btn-outline {
  background: transparent;
  color: var(--primary);
  border: 2px solid var(--primary);
}
.btn-outline:hover {
  background: var(--primary);
  color: #fff;
  transform: translateY(-2px);
}

/* ── FAQ ── */
#faq {
  padding: 100px 0;
  background: var(--bg);
}
#faq h2 { 
  font-size: 2rem; 
  font-weight: 700; 
  text-align: center; 
  margin-bottom: 16px;
  max-width: 700px;
  margin-left: auto;
  margin-right: auto;
}
#faq .section-sub {
  text-align: center; 
  color: var(--text-muted); 
  margin-bottom: 64px;
  font-size: 1.1rem;
  max-width: 600px;
  margin-left: auto;
  margin-right: auto;
}
.faq-list { 
  max-width: 800px; 
  margin: 0 auto;
}
.faq-category {
  margin-bottom: 32px;
}
.faq-category h3 {
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--primary);
  margin-bottom: 20px;
  padding-bottom: 12px;
  border-bottom: 2px solid var(--primary);
  display: inline-block;
}
.faq-item {
  border: 1px solid var(--border); 
  border-radius: var(--radius);
  margin-bottom: 16px; 
  overflow: hidden;
  box-shadow: 0 4px 12px rgba(0,0,0,0.05);
  transition: all 0.3s ease;
}
.faq-item:hover {
  box-shadow: 0 8px 20px rgba(0,0,0,0.1);
}
.faq-q {
  padding: 24px 28px; 
  cursor: pointer;
  display: flex; 
  justify-content: space-between; 
  align-items: center;
  font-weight: 600; 
  user-select: none;
  transition: background 0.2s;
  background: var(--bg2);
}
.faq-q:hover { 
  background: var(--bg3); 
}
.faq-q .arrow { 
  font-size: 1.2rem; 
  transition: transform 0.3s; 
  color: var(--text-muted);
  font-weight: 300;
}
.faq-item.open .faq-q .arrow { 
  transform: rotate(180deg);
  color: var(--primary);
}
.faq-a {
  max-height: 0; 
  overflow: hidden; 
  transition: max-height 0.35s ease, padding 0.35s;
  padding: 0 28px; 
  color: var(--text-muted); 
  font-size: 0.95rem; 
  line-height: 1.8;
}
.faq-item.open .faq-a { 
  max-height: 500px; 
  padding: 0 28px 24px;
}
.faq-a p {
  margin-bottom: 12px;
}
.faq-a p:last-child {
  margin-bottom: 0;
}

/* ── CTA底部 ── */
.cta-bottom {
  background: linear-gradient(135deg, rgba(59,130,246,0.1) 0%, rgba(16,185,129,0.1) 100%);
  border-top: 1px solid var(--border);
  text-align: center; 
  padding: 100px 24px;
}
.cta-gift {
  display: inline-flex; 
  align-items: center; 
  gap: 12px;
  background: rgba(59,130,246,0.1); 
  border: 1px solid rgba(59,130,246,0.3);
  color: var(--primary); 
  padding: 10px 24px; 
  border-radius: 999px;
  font-size: 1rem; 
  margin-bottom: 32px;
  font-weight: 500;
}
.cta-bottom h2 { 
  font-size: clamp(1.8rem, 5vw, 2.5rem); 
  font-weight: 800; 
  margin-bottom: 24px;
  max-width: 800px;
  margin-left: auto;
  margin-right: auto;
  line-height: 1.2;
}
.cta-bottom p { 
  color: var(--text-muted); 
  margin-bottom: 48px; 
  font-size: 1.15rem;
  max-width: 600px;
  margin-left: auto;
  margin-right: auto;
  line-height: 1.6;
}
.cta-steps {
  display: flex; 
  justify-content: center; 
  gap: 48px; 
  flex-wrap: wrap; 
  margin-bottom: 64px;
  max-width: 900px;
  margin-left: auto;
  margin-right: auto;
}
.cta-step { 
  text-align: center; 
  flex: 1;
  min-width: 200px;
}
.cta-step-icon {
  width: 64px; 
  height: 64px;
  display: flex; 
  align-items: center; 
  justify-content: center;
  margin: 0 auto 20px;
  background: rgba(59,130,246,0.1);
  border: 1px solid rgba(59,130,246,0.3);
  border-radius: 50%;
  transition: all 0.3s ease;
}
.cta-step:hover .cta-step-icon {
  transform: translateY(-4px);
  box-shadow: 0 8px 20px rgba(59,130,246,0.3);
}
.cta-step-icon svg {
  width: 32px;
  height: 32px;
  stroke: var(--primary);
  stroke-width: 2;
  fill: none;
}
.cta-step-num {
  width: 44px; 
  height: 44px; 
  border-radius: 50%;
  background: var(--primary); 
  color: #fff;
  display: flex; 
  align-items: center; 
  justify-content: center;
  font-weight: 700; 
  margin: 0 auto 12px;
  font-size: 1.1rem;
}
.cta-step p { 
  font-size: 0.95rem; 
  color: var(--text-muted);
  margin-bottom: 0;
  line-height: 1.4;
}

/* ── Footer ── */
footer {
  background: var(--bg2); 
  border-top: 1px solid var(--border);
  padding: 48px 24px; 
  text-align: center;
}
.footer-links { 
  display: flex; 
  justify-content: center; 
  gap: 32px; 
  flex-wrap: wrap; 
  margin-bottom: 24px;
  max-width: 900px;
  margin-left: auto;
  margin-right: auto;
}
.footer-links a { 
  color: var(--text-muted); 
  font-size: 0.95rem;
  font-weight: 500;
  transition: all 0.3s ease;
}
.footer-links a:hover { 
  color: var(--primary); 
  text-decoration: none;
  transform: translateY(-2px);
}
footer p { 
  font-size: 0.85rem; 
  color: var(--text-muted);
  line-height: 1.5;
}

/* ── 响应式 ── */
@media (max-width: 1200px) {
  .stat-row {
    gap: 16px;
  }
  .stat {
    min-width: 130px;
  }
  .model-grid {
    grid-template-columns: repeat(4, 1fr);
  }
}

@media (max-width: 1024px) {
  .article-list { grid-template-columns: repeat(2, 1fr); }
  .hero-stats {
    padding: 32px;
  }
  .stat {
    min-width: 120px;
  }
  .stat-num {
    font-size: 1.8rem;
  }
  .nav-links {
    gap: 16px;
  }
  .model-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

@media (max-width: 768px) {
  .article-list { grid-template-columns: repeat(2, 1fr); }
  .price-info { grid-template-columns: 1fr; }
  .calc-example-grid { grid-template-columns: 1fr; }
  .stat-row {
    flex-wrap: wrap;
  }
  .stat {
    flex: 1 1 calc(50% - 12px);
    min-width: 140px;
  }
  .nav-links {
    display: none;
  }
  .mobile-menu-btn {
    display: block;
  }
  .model-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .feature-grid {
    grid-template-columns: 1fr;
  }
  .hero-title {
    font-size: clamp(1.5rem, 5vw, 2.5rem);
  }
  .hero-title-sub {
    font-size: 0.7em;
  }
}

@media (max-width: 640px) {
  section { padding: 60px 0; }
  .hero { padding: 70px 0 60px; }
  .hero-stats {
    padding: 24px;
  }
  .stat-row {
    gap: 16px;
  }
  .stat {
    flex: 1 1 100%;
    min-width: 100%;
  }
  .nav-links { display: none; }
  .calc-box { padding: 24px; }
  .cta-steps { gap: 20px; }
  .article-list { grid-template-columns: 1fr; }
  .article-image { height: 150px; }
  .calc-example-grid { grid-template-columns: 1fr; }
  .price-summary { padding: 16px; }
  .feature-grid {
    grid-template-columns: 1fr;
  }
  .model-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .hero-title {
    font-size: clamp(1.2rem, 5vw, 2rem);
  }
  .hero-title-main {
    margin-bottom: 4px;
  }
  .hero-title-sub {
    font-size: 0.6em;
  }
  .hero-title-sub .brand {
    font-size: 0.8em;
  }
}