/* ============================================================
   奈云 NaiYun 官网样式表 (style.css)
   极简云端风格 | Minimal Cloud Style
   主背景: #F8FAFC | 主文字: #172033 | 品牌蓝: #315CF5
   浅蓝: #EAF0FF | 辅助灰: #64748B | 白色区域: #FFFFFF
   ============================================================ */

:root {
  --bg-main: #F8FAFC;
  --text-main: #172033;
  --text-secondary: #64748B;
  --text-muted: #94A3B8;
  --brand-blue: #315CF5;
  --brand-blue-hover: #2348DE;
  --brand-blue-light: #EAF0FF;
  --card-bg: #FFFFFF;
  --border-light: #E2E8F0;
  --border-subtle: #F1F5F9;
  --shadow-subtle: 0 4px 20px rgba(0, 0, 0, 0.04);
  --shadow-card: 0 8px 30px rgba(23, 32, 51, 0.06);
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-pill: 9999px;
  --container-width: 1200px;
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
}

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

html {
  font-size: 16px;
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-sans);
  background-color: var(--bg-main);
  color: var(--text-main);
  line-height: 1.65;
  overflow-x: hidden;
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

a {
  color: inherit;
  text-decoration: none;
  transition: color 0.2s ease;
}

button {
  font-family: inherit;
  cursor: pointer;
  border: none;
  background: none;
}

.container {
  width: 100%;
  max-width: var(--container-width);
  margin-left: auto;
  margin-right: auto;
  padding-left: 24px;
  padding-right: 24px;
}

/* 顶部导航 Header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: rgba(248, 250, 252, 0.92);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-light);
  transition: box-shadow 0.2s ease;
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
  width: 100%;
}

.brand-logo {
  display: flex;
  align-items: center;
  gap: 12px;
  font-weight: 700;
  font-size: 1.25rem;
  color: var(--text-main);
  letter-spacing: -0.02em;
  flex-shrink: 0;
}

.brand-logo img {
  width: 36px;
  height: 36px;
  border-radius: var(--radius-sm);
  object-fit: contain;
}

.brand-text {
  display: flex;
  align-items: baseline;
  gap: 6px;
}

.brand-en {
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--brand-blue);
  letter-spacing: 0.02em;
}

.nav-desktop {
  display: flex;
  align-items: center;
  gap: 28px;
}

.nav-link {
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--text-secondary);
  transition: color 0.2s ease;
  position: relative;
  padding: 6px 0;
}

.nav-link:hover, .nav-link.active {
  color: var(--brand-blue);
}

.nav-cta-group {
  display: flex;
  align-items: center;
  gap: 14px;
}

/* 移动端汉堡菜单按钮 */
.menu-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  width: 40px;
  height: 40px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border-light);
  background: var(--card-bg);
  gap: 5px;
  flex-shrink: 0;
}

.menu-toggle span {
  width: 20px;
  height: 2px;
  background-color: var(--text-main);
  transition: transform 0.2s ease, opacity 0.2s ease;
}

.menu-toggle.is-active span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.menu-toggle.is-active span:nth-child(2) {
  opacity: 0;
}

.menu-toggle.is-active span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* 移动端菜单折叠层 */
.mobile-nav-drawer {
  display: none;
  position: absolute;
  top: 72px;
  left: 0;
  width: 100%;
  background: var(--card-bg);
  border-bottom: 1px solid var(--border-light);
  padding: 20px 24px;
  box-shadow: 0 10px 30px rgba(0,0,0,0.08);
}

.mobile-nav-drawer.is-open {
  display: block;
}

.mobile-nav-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.mobile-nav-link {
  font-size: 1.05rem;
  font-weight: 500;
  color: var(--text-main);
  padding: 8px 0;
  border-bottom: 1px solid var(--border-subtle);
  display: block;
}

/* 基础按钮 */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 10px 22px;
  font-size: 0.95rem;
  font-weight: 600;
  border-radius: var(--radius-md);
  transition: all 0.2s ease;
  white-space: nowrap;
  line-height: 1.4;
}

.btn-primary {
  background-color: var(--brand-blue);
  color: #FFFFFF;
  box-shadow: 0 2px 8px rgba(49, 92, 245, 0.25);
}

.btn-primary:hover {
  background-color: var(--brand-blue-hover);
  color: #FFFFFF;
  transform: translateY(-1px);
}

.btn-secondary {
  background-color: var(--brand-blue-light);
  color: var(--brand-blue);
}

.btn-secondary:hover {
  background-color: #DDE8FF;
  color: var(--brand-blue-hover);
  transform: translateY(-1px);
}

.btn-outline {
  background-color: transparent;
  color: var(--text-main);
  border: 1px solid var(--border-light);
}

.btn-outline:hover {
  background-color: #FFFFFF;
  border-color: var(--brand-blue);
  color: var(--brand-blue);
}

.btn-lg {
  padding: 14px 30px;
  font-size: 1.05rem;
  border-radius: var(--radius-md);
}

.btn-block {
  width: 100%;
}

/* 顶部状态提示横条 */
.brand-status-bar {
  background: var(--brand-blue-light);
  border-bottom: 1px solid #DDE8FF;
  padding: 8px 0;
  font-size: 0.85rem;
  color: #1E3A8A;
}

.brand-status-bar .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 8px;
}

.status-tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-weight: 600;
}

.status-dot {
  width: 8px;
  height: 8px;
  background-color: #10B981;
  border-radius: 50%;
  display: inline-block;
}

/* 首屏 Hero Section */
.hero-section {
  padding: 72px 0 64px;
  position: relative;
  overflow: hidden;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  align-items: center;
  gap: 48px;
  min-width: 0;
}

.hero-content {
  min-width: 0;
}

.hero-visual {
  display: flex;
  justify-content: center;
  align-items: center;
  width: 100%;
  min-width: 0;
}

.hero-svg-frame {
  width: 100%;
  max-width: 460px;
  min-width: 0;
  background: var(--card-bg);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-lg);
  padding: 24px;
  box-shadow: var(--shadow-card);
}

.hero-svg-frame img {
  width: 100%;
  height: auto;
  display: block;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: var(--brand-blue-light);
  color: var(--brand-blue);
  font-size: 0.85rem;
  font-weight: 600;
  padding: 6px 14px;
  border-radius: var(--radius-pill);
  margin-bottom: 20px;
}

.hero-title {
  font-size: 3rem;
  font-weight: 800;
  line-height: 1.2;
  letter-spacing: -0.03em;
  color: var(--text-main);
  margin-bottom: 16px;
}

.hero-subtitle {
  font-size: 1.35rem;
  font-weight: 600;
  color: var(--brand-blue);
  margin-bottom: 20px;
  line-height: 1.4;
}

.hero-desc {
  font-size: 1.05rem;
  color: var(--text-secondary);
  line-height: 1.75;
  margin-bottom: 32px;
  max-width: 600px;
}

.hero-cta {
  display: flex;
  align-items: center;
  gap: 16px;
  flex-wrap: wrap;
  margin-bottom: 32px;
}

.hero-meta-note {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.85rem;
  color: var(--text-muted);
}

.hero-meta-note svg {
  color: var(--brand-blue);
  flex-shrink: 0;
}

/* 分隔线与板块标题 */
.section-divider {
  width: 100%;
  height: 1px;
  background-color: var(--border-light);
  margin: 0;
}

.section {
  padding: 80px 0;
}

.section-alt {
  background-color: #FFFFFF;
}

.section-header {
  text-align: center;
  max-width: 720px;
  margin: 0 auto 52px;
}

.section-tag {
  display: inline-block;
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--brand-blue);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-bottom: 12px;
}

.section-title {
  font-size: 2.25rem;
  font-weight: 800;
  line-height: 1.3;
  color: var(--text-main);
  letter-spacing: -0.02em;
  margin-bottom: 16px;
}

.section-desc {
  font-size: 1.05rem;
  color: var(--text-secondary);
  line-height: 1.7;
}

/* 五、服务优势：精准 4 项 */
.features-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 28px;
}

.feature-card {
  background: var(--card-bg);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-lg);
  padding: 36px 32px;
  box-shadow: var(--shadow-subtle);
  transition: transform 0.2s ease, border-color 0.2s ease;
  display: flex;
  flex-direction: column;
}

.feature-card:hover {
  transform: translateY(-2px);
  border-color: #CBD5E1;
}

.feature-icon-box {
  width: 52px;
  height: 52px;
  border-radius: var(--radius-md);
  background: var(--brand-blue-light);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 22px;
  color: var(--brand-blue);
  flex-shrink: 0;
}

.feature-title {
  font-size: 1.3rem;
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 12px;
}

.feature-text {
  font-size: 0.975rem;
  color: var(--text-secondary);
  line-height: 1.75;
  margin-bottom: 18px;
  flex-grow: 1;
}

.feature-badge-row {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  padding-top: 14px;
  border-top: 1px solid var(--border-subtle);
}

.feature-pill {
  font-size: 0.8rem;
  background: var(--bg-main);
  color: var(--text-secondary);
  padding: 4px 10px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border-light);
}

/* 六、套餐价格：三栏简洁卡片 */
.plans-wrapper {
  max-width: 1100px;
  margin: 0 auto;
}

.plans-notice-box {
  background: #FFFBEB;
  border: 1px solid #FDE68A;
  border-radius: var(--radius-md);
  padding: 14px 20px;
  margin-bottom: 36px;
  font-size: 0.9rem;
  color: #92400E;
  display: flex;
  align-items: center;
  gap: 12px;
}

.plans-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
  align-items: stretch;
}

.plan-card {
  background: var(--card-bg);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-lg);
  padding: 36px 28px;
  box-shadow: var(--shadow-subtle);
  display: flex;
  flex-direction: column;
  position: relative;
  transition: transform 0.2s ease, border-color 0.2s ease;
}

.plan-card:hover {
  transform: translateY(-3px);
  border-color: #CBD5E1;
}

.plan-card.plan-featured {
  border-color: var(--brand-blue);
  box-shadow: 0 10px 36px rgba(49, 92, 245, 0.12);
}

.plan-featured-tag {
  position: absolute;
  top: -14px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--brand-blue);
  color: #FFFFFF;
  font-size: 0.75rem;
  font-weight: 700;
  padding: 4px 14px;
  border-radius: var(--radius-pill);
  letter-spacing: 0.04em;
}

.plan-header {
  margin-bottom: 24px;
  text-align: center;
}

.plan-name {
  font-size: 1.35rem;
  font-weight: 800;
  color: var(--text-main);
  margin-bottom: 4px;
}

.plan-name-en {
  font-size: 0.825rem;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 16px;
}

.plan-price-wrap {
  display: flex;
  align-items: baseline;
  justify-content: center;
  gap: 2px;
  margin-bottom: 8px;
}

.plan-currency {
  font-size: 1.35rem;
  font-weight: 700;
  color: var(--brand-blue);
}

.plan-amount {
  font-size: 3rem;
  font-weight: 800;
  line-height: 1;
  color: var(--brand-blue);
  letter-spacing: -0.03em;
}

.plan-period {
  font-size: 0.95rem;
  color: var(--text-secondary);
  font-weight: 500;
}

.plan-data-pill {
  display: inline-block;
  background: var(--brand-blue-light);
  color: var(--brand-blue);
  font-size: 0.9rem;
  font-weight: 700;
  padding: 4px 14px;
  border-radius: var(--radius-pill);
  margin-top: 8px;
}

.plan-audience {
  font-size: 0.875rem;
  color: var(--text-secondary);
  background: var(--bg-main);
  padding: 12px 14px;
  border-radius: var(--radius-sm);
  margin: 18px 0 24px;
  line-height: 1.5;
  text-align: left;
}

.plan-features {
  list-style: none;
  margin-bottom: 32px;
  flex-grow: 1;
}

.plan-features li {
  font-size: 0.9rem;
  color: var(--text-secondary);
  padding: 9px 0;
  border-bottom: 1px solid var(--border-subtle);
  display: flex;
  align-items: flex-start;
  gap: 10px;
  line-height: 1.5;
}

.plan-features li svg {
  color: var(--brand-blue);
  flex-shrink: 0;
  margin-top: 2px;
}

.plan-action {
  margin-top: auto;
}

.plan-status-caption {
  font-size: 0.775rem;
  color: var(--text-muted);
  text-align: center;
  margin-top: 10px;
}

/* 使用指南 Guide Section */
.guide-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}

.guide-step-card {
  background: var(--card-bg);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  padding: 24px 20px;
  display: flex;
  flex-direction: column;
}

.guide-step-num {
  font-size: 0.85rem;
  font-weight: 800;
  color: var(--brand-blue);
  background: var(--brand-blue-light);
  width: 32px;
  height: 32px;
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 16px;
}

.guide-step-title {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 8px;
}

.guide-step-desc {
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* 七、文章中心 Article Cards */
.articles-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
}

.article-card {
  background: var(--card-bg);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-lg);
  padding: 28px 24px;
  box-shadow: var(--shadow-subtle);
  display: flex;
  flex-direction: column;
  transition: transform 0.2s ease, border-color 0.2s ease;
}

.article-card:hover {
  transform: translateY(-3px);
  border-color: #CBD5E1;
}

.article-meta-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 14px;
}

.article-category {
  font-size: 0.8rem;
  font-weight: 700;
  color: var(--brand-blue);
  background: var(--brand-blue-light);
  padding: 3px 10px;
  border-radius: var(--radius-sm);
}

.article-date {
  font-size: 0.8rem;
  color: var(--text-muted);
}

.article-card-title {
  font-size: 1.15rem;
  font-weight: 700;
  line-height: 1.45;
  color: var(--text-main);
  margin-bottom: 12px;
  transition: color 0.2s ease;
}

.article-card:hover .article-card-title {
  color: var(--brand-blue);
}

.article-summary {
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.65;
  margin-bottom: 20px;
  flex-grow: 1;
}

.article-read-btn {
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--brand-blue);
  display: inline-flex;
  align-items: center;
  gap: 6px;
  margin-top: auto;
  padding-top: 14px;
  border-top: 1px solid var(--border-subtle);
}

.article-read-btn svg {
  transition: transform 0.2s ease;
}

.article-card:hover .article-read-btn svg {
  transform: translateX(3px);
}

/* 九、FAQ 手风琴列表 */
.faq-container {
  max-width: 840px;
  margin: 0 auto;
}

.faq-list {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.faq-item {
  background: var(--card-bg);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  overflow: hidden;
  transition: border-color 0.2s ease;
}

.faq-item.is-active {
  border-color: #CBD5E1;
}

.faq-question {
  width: 100%;
  text-align: left;
  padding: 20px 24px;
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--text-main);
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
  cursor: pointer;
  background: transparent;
}

.faq-toggle-icon {
  width: 22px;
  height: 22px;
  color: var(--brand-blue);
  flex-shrink: 0;
  transition: transform 0.25s ease;
}

.faq-item.is-active .faq-toggle-icon {
  transform: rotate(180deg);
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s ease, padding 0.3s ease;
  padding: 0 24px;
  background: #FCFDFD;
}

.faq-item.is-active .faq-answer {
  max-height: 600px;
  padding: 0 24px 22px 24px;
  border-top: 1px solid var(--border-subtle);
}

.faq-answer p {
  font-size: 0.95rem;
  color: var(--text-secondary);
  line-height: 1.75;
  padding-top: 16px;
}

.faq-answer ul {
  padding-left: 20px;
  margin-top: 8px;
  color: var(--text-secondary);
  font-size: 0.95rem;
}

/* 十二、页脚 Footer */
.site-footer {
  background: #FFFFFF;
  border-top: 1px solid var(--border-light);
  padding: 64px 0 32px;
  color: var(--text-secondary);
}

.footer-top {
  display: grid;
  grid-template-columns: 1.5fr 1fr 1fr 1fr;
  gap: 40px;
  margin-bottom: 48px;
}

.footer-brand-desc {
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.7;
  margin: 16px 0 20px;
  max-width: 320px;
}

.footer-col-title {
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 18px;
}

.footer-links {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.footer-links a {
  font-size: 0.9rem;
  color: var(--text-secondary);
}

.footer-links a:hover {
  color: var(--brand-blue);
}

.footer-disclaimer-box {
  background: var(--bg-main);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  padding: 16px 20px;
  margin-bottom: 32px;
  font-size: 0.825rem;
  color: var(--text-muted);
  line-height: 1.6;
}

.footer-bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 16px;
  padding-top: 24px;
  border-top: 1px solid var(--border-light);
  font-size: 0.85rem;
}

/* 统一提示模态窗 (Modal) */
.ny-modal-backdrop {
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  background: rgba(15, 23, 42, 0.45);
  backdrop-filter: blur(4px);
  z-index: 9999;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 20px;
}

.ny-modal-card {
  background: #FFFFFF;
  border-radius: var(--radius-lg);
  max-width: 480px;
  width: 100%;
  padding: 28px;
  box-shadow: 0 20px 40px rgba(0,0,0,0.15);
  border: 1px solid var(--border-light);
  animation: modalFadeIn 0.2s ease-out;
}

@keyframes modalFadeIn {
  from { opacity: 0; transform: scale(0.96); }
  to { opacity: 1; transform: scale(1); }
}

.ny-modal-header {
  display: flex;
  align-items: center;
  gap: 12px;
  position: relative;
  margin-bottom: 16px;
}

.ny-modal-icon-badge {
  width: 40px;
  height: 40px;
  border-radius: var(--radius-md);
  background: var(--brand-blue-light);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.ny-modal-title {
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--text-main);
  flex-grow: 1;
}

.ny-modal-close {
  font-size: 1.5rem;
  color: var(--text-muted);
  width: 32px;
  height: 32px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-sm);
}

.ny-modal-close:hover {
  background: var(--bg-main);
  color: var(--text-main);
}

.ny-modal-body {
  margin-bottom: 24px;
}

.ny-modal-text {
  font-size: 0.95rem;
  color: var(--text-secondary);
  line-height: 1.7;
  margin-bottom: 16px;
}

.ny-modal-meta-box {
  background: var(--bg-main);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  padding: 12px 14px;
  font-size: 0.825rem;
}

.ny-meta-item {
  display: flex;
  justify-content: space-between;
  padding: 4px 0;
  border-bottom: 1px solid var(--border-subtle);
}

.ny-meta-item:last-child {
  border-bottom: none;
}

.ny-meta-item span {
  color: var(--text-muted);
}

.ny-meta-item strong {
  color: var(--text-main);
}

.ny-modal-footer {
  display: flex;
  justify-content: flex-end;
}

/* ============================================================
   响应式断点适配 (375px, 390px, 768px, 1024px, 1440px)
   ============================================================ */

@media (max-width: 1024px) {
  .hero-grid {
    grid-template-columns: 1fr;
    gap: 40px;
  }
  .hero-visual {
    order: -1;
  }
  .plans-grid {
    grid-template-columns: 1fr;
    max-width: 480px;
    margin: 0 auto;
  }
  .articles-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .guide-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .footer-top {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 768px) {
  .nav-desktop, .nav-cta-group {
    display: none;
  }
  .menu-toggle {
    display: flex;
  }
  .brand-status-bar .container {
    flex-direction: column;
    text-align: center;
    gap: 4px;
    font-size: 0.775rem;
  }
  .hero-section {
    padding: 36px 0 48px;
  }
  .hero-svg-frame {
    padding: 16px;
    max-width: 100%;
  }
  .hero-title {
    font-size: 2.1rem;
    line-height: 1.25;
  }
  .hero-subtitle {
    font-size: 1.1rem;
  }
  .section-title {
    font-size: 1.75rem;
  }
  .features-grid {
    grid-template-columns: 1fr;
  }
  .articles-grid {
    grid-template-columns: 1fr;
  }
  .guide-grid {
    grid-template-columns: 1fr;
  }
  .footer-top {
    grid-template-columns: 1fr;
  }
  .footer-bottom {
    flex-direction: column;
    text-align: center;
  }
}

@media (max-width: 390px) {
  .container {
    padding-left: 14px;
    padding-right: 14px;
  }
  .brand-logo {
    gap: 8px;
    font-size: 1.15rem;
  }
  .brand-logo img {
    width: 32px;
    height: 32px;
  }
  .hero-title {
    font-size: 1.75rem;
    word-break: break-word;
  }
  .hero-subtitle {
    font-size: 1rem;
    word-break: break-word;
  }
  .hero-cta {
    flex-direction: column;
    width: 100%;
  }
  .hero-cta .btn {
    width: 100%;
  }
  .plan-card {
    padding: 28px 18px;
  }
}

/* 无障碍辅助：尊重用户减弱动态效果设定 */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}