/* ========================================================
   DeepSeek Polar Whiteout System (极地白茫设计系统)
   Design Language: 几乎全白，地平线模糊，雪的颗粒可见
   Debossed letterpress on snowfield, remote wind mast indicator
   Responsive Breakpoints: Desktop (>1200px), Tablet (968px), Mobile (640px)
   ======================================================== */

:root {
  /* 极地色盘：纯净冰雪、漫反射灰白、深海冷蓝 */
  --bg-polar: #FAFBFD;
  --bg-surface: #FFFFFF;
  --bg-snow-tint: #F3F6F9;
  --bg-snow-subtle: #EDF2F7;
  --bg-frost: rgba(255, 255, 255, 0.82);
  --border-ice: #E2E8F0;
  --border-light: #EDF2F7;
  --border-polar-glass: rgba(226, 232, 240, 0.7);

  /* 文字层次：浅灰与极地玄墨 */
  --text-main: #1E293B;
  --text-deboss: #334155;
  --text-muted: #64748B;
  --text-light: #94A3B8;
  --text-faint: #CBD5E1;

  /* 品牌色与强调色：冷海极冰蓝与极光青 */
  --brand-primary: #0284C7;
  --brand-hover: #0369A1;
  --brand-soft: rgba(2, 132, 199, 0.08);
  --brand-border: rgba(2, 132, 199, 0.25);
  --accent-cyan: #0D9488;
  --accent-gold: #D97706;

  /* 统一尺寸与圆角规范 */
  --radius-card: 12px;
  --radius-btn: 12px;
  --radius-logo: 8px;
  --radius-pill: 9999px;
  --radius-demo: 20px;

  /* 阴影与压印质感 */
  --shadow-snow: 0 4px 20px -2px rgba(148, 163, 184, 0.08);
  --shadow-hover: 0 12px 28px -4px rgba(2, 132, 199, 0.12);
  --shadow-mast: 0 2px 10px rgba(15, 23, 42, 0.05);

  /* 字体系统 */
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --font-mono: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace;
}

/* CSS Reset & 全局底纹（雪粒漫反射微晶纹理与地平线模糊） */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  font-family: var(--font-sans);
  background-color: var(--bg-polar);
  color: var(--text-main);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  scroll-behavior: smooth;
}

body {
  position: relative;
  min-height: 100vh;
  overflow-x: hidden;
  background-image: 
    radial-gradient(circle at 50% 0%, rgba(226, 232, 240, 0.5) 0%, transparent 65%),
    radial-gradient(circle at 100% 40%, rgba(241, 245, 249, 0.7) 0%, transparent 50%),
    radial-gradient(circle at 0% 80%, rgba(248, 250, 252, 0.9) 0%, transparent 40%);
}

/* 极地微雪颗粒叠加层 */
.snow-grain-overlay {
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 1;
  opacity: 0.35;
  background-image: radial-gradient(#94A3B8 0.65px, transparent 0.65px);
  background-size: 28px 28px;
}

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

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

/* ========================================================
   全局排版与容器约束
   左右内边距：桌面 64px，平板 32px，手机 16px
   上下内边距：桌面约 100px
   大标题字距略紧，正文行高约 1.7
   ======================================================== */
.container {
  max-width: 1280px;
  margin-left: auto;
  margin-right: auto;
  padding-left: 64px;
  padding-right: 64px;
}

.section-wrapper {
  padding-top: 100px;
  padding-bottom: 100px;
  position: relative;
  z-index: 2;
}

/* 单轴对齐体系：严格区分整段居中或整段左对齐 */
.align-center {
  text-align: center;
}

.align-left {
  text-align: left;
}

.section-header-center {
  text-align: center;
  max-width: 720px;
  margin: 0 auto 56px auto;
}

.section-title-center {
  font-size: 38px;
  font-weight: 700;
  letter-spacing: -0.025em;
  color: var(--text-deboss);
  text-shadow: 0 1px 1px #FFFFFF, 0 -1px 1px rgba(15, 23, 42, 0.08);
  margin-bottom: 16px;
  line-height: 1.25;
}

.section-desc-center {
  font-size: 15px;
  color: var(--text-muted);
  line-height: 1.7;
}

/* ========================================================
   主按钮层级约束：
   全页只有一个主按钮层级：导航和下载区用实心品牌色，其余用描边或文字按钮
   ======================================================== */
.btn-primary-solid {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background-color: var(--brand-primary);
  color: #FFFFFF !important;
  font-size: 14px;
  font-weight: 600;
  padding: 10px 22px;
  border-radius: var(--radius-btn);
  border: 1px solid var(--brand-primary);
  box-shadow: 0 2px 8px rgba(2, 132, 199, 0.25);
  cursor: pointer;
  white-space: nowrap;
  transition: all 0.2s cubic-bezier(0.16, 1, 0.3, 1);
}

.btn-primary-solid:hover {
  background-color: var(--brand-hover);
  border-color: var(--brand-hover);
  box-shadow: 0 4px 14px rgba(2, 132, 199, 0.35);
  transform: translateY(-1px);
}

.btn-outline-secondary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background-color: var(--bg-surface);
  color: var(--text-main);
  font-size: 14px;
  font-weight: 500;
  padding: 10px 22px;
  border-radius: var(--radius-btn);
  border: 1px solid var(--border-ice);
  cursor: pointer;
  white-space: nowrap;
  transition: all 0.2s ease;
}

.btn-outline-secondary:hover {
  border-color: var(--brand-primary);
  color: var(--brand-primary);
  background-color: var(--brand-soft);
  transform: translateY(-1px);
}

.btn-ghost-nav {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background: transparent;
  color: var(--text-muted);
  font-size: 14px;
  font-weight: 500;
  padding: 8px 16px;
  border-radius: var(--radius-btn);
  border: 1px solid transparent;
  cursor: pointer;
  transition: all 0.2s ease;
}

.btn-ghost-nav:hover {
  color: var(--text-main);
  background-color: rgba(226, 232, 240, 0.35);
}

/* ========================================================
   导航栏 (Navbar)
   固定在顶部，高 64px。白底约 80% 透明，背后模糊，底边极浅分割线。
   左：圆角方标 + 字标。中：4 条 14px 灰色文字链接，间距约 36px。
   右：幽灵按钮「登录」+ 品牌色实心主按钮。
   ======================================================== */
.navbar-fixed {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: 64px;
  background-color: var(--bg-frost);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--border-light);
  z-index: 1000;
  display: flex;
  align-items: center;
}

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

.nav-brand {
  display: flex;
  align-items: center;
  gap: 12px;
}

.nav-brand-logo {
  width: 32px;
  height: 32px;
  border-radius: var(--radius-logo);
  object-fit: cover;
  border: 1px solid var(--border-ice);
  background-color: #FFFFFF;
  box-shadow: 0 1px 3px rgba(0,0,0,0.04);
}

.nav-brand-text {
  font-size: 18px;
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--text-deboss);
  text-shadow: 0 1px 0 #FFFFFF;
}

.nav-links-center {
  display: flex;
  align-items: center;
  gap: 36px;
}

.nav-link-item {
  font-size: 14px;
  color: var(--text-muted);
  font-weight: 500;
  position: relative;
  transition: color 0.2s ease;
}

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

.nav-actions-right {
  display: flex;
  align-items: center;
  gap: 12px;
}

/* 汉堡按钮 (Narrow < 968px) */
.mobile-menu-btn {
  display: none;
  background: transparent;
  border: 1px solid var(--border-ice);
  border-radius: var(--radius-logo);
  width: 38px;
  height: 38px;
  padding: 8px;
  cursor: pointer;
  align-items: center;
  justify-content: center;
  color: var(--text-main);
}

.mobile-menu-drawer {
  display: none;
  position: fixed;
  top: 64px;
  left: 0;
  right: 0;
  background-color: rgba(255, 255, 255, 0.98);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border-ice);
  padding: 24px 32px;
  box-shadow: 0 12px 30px rgba(0, 0, 0, 0.06);
  z-index: 999;
}

.mobile-menu-drawer.open {
  display: block;
}

.mobile-nav-list {
  display: flex;
  flex-direction: column;
  gap: 18px;
  margin-bottom: 24px;
}

.mobile-nav-item {
  font-size: 15px;
  color: var(--text-muted);
  font-weight: 500;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--border-light);
}

.mobile-nav-item:hover {
  color: var(--brand-primary);
}

/* ========================================================
   首屏 (Hero Section)
   两列 1:1，间距 60px，上内边距约 140px，最小高度约一屏。
   左栏：
     1. 胶囊公告 (小圆点 + 发布信息)
     2. 品牌色产品名 约42px 字距略紧
     3. 主张 约24px 字距略宽
     4. 灰色介绍 最宽约600px
     5. 两个入口 (主入口品牌色实心，次入口白底描边)
     6. 品牌色信息条 (三行以内)
     7. 三条短信任点 带小勾
   右栏：最宽约 460px 演示卡片，圆角 20px
   呼应“极地白茫，雪面压印，远处测风杆”
   ======================================================== */
.hero-section {
  padding-top: 140px;
  padding-bottom: 90px;
  min-height: 100vh;
  display: flex;
  align-items: center;
  position: relative;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
  width: 100%;
}

.hero-left {
  text-align: left;
}

/* 1. 胶囊公告 */
.hero-capsule {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background-color: #FFFFFF;
  border: 1px solid var(--border-ice);
  border-radius: var(--radius-pill);
  padding: 6px 16px 6px 12px;
  margin-bottom: 24px;
  box-shadow: 0 1px 3px rgba(0,0,0,0.03);
}

.capsule-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background-color: var(--brand-primary);
  box-shadow: 0 0 0 3px rgba(2, 132, 199, 0.18);
  animation: pulseSnow 2.4s infinite ease-in-out;
}

@keyframes pulseSnow {
  0%, 100% { transform: scale(1); opacity: 1; }
  50% { transform: scale(1.25); opacity: 0.7; }
}

.capsule-text {
  font-size: 13px;
  color: var(--text-muted);
  font-weight: 500;
}

/* 2. 品牌色产品名 */
.hero-product-name {
  font-size: 42px;
  font-weight: 800;
  letter-spacing: -0.03em;
  color: var(--brand-primary);
  line-height: 1.15;
  margin-bottom: 12px;
  text-shadow: 0 1px 2px rgba(255, 255, 255, 0.8), 0 -1px 1px rgba(2, 132, 199, 0.15);
}

/* 3. 主张 */
.hero-proposition {
  font-size: 24px;
  font-weight: 600;
  letter-spacing: 0.04em;
  color: var(--text-deboss);
  margin-bottom: 18px;
  line-height: 1.35;
  text-shadow: 0 1px 0 #FFFFFF;
}

/* 4. 灰色介绍 */
.hero-desc {
  max-width: 600px;
  font-size: 15px;
  color: var(--text-muted);
  line-height: 1.7;
  margin-bottom: 30px;
}

/* 5. 两个入口 (主实心，次白底描边) */
.hero-actions {
  display: flex;
  align-items: center;
  gap: 16px;
  margin-bottom: 28px;
  flex-wrap: wrap;
}

/* 极地测风杆入口装饰 (Polar Wind Mast Widget) */
.wind-mast-indicator {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 12px;
  color: var(--text-light);
  padding: 4px 10px;
  border-left: 2px solid var(--brand-primary);
  margin-left: 8px;
}

.wind-mast-icon {
  width: 14px;
  height: 14px;
  animation: rotateMast 7s linear infinite;
}

@keyframes rotateMast {
  from { transform: rotate(0deg); }
  to { transform: rotate(360deg); }
}

/* 6. 品牌色信息条 (三行以内) */
.hero-notice-bar {
  background-color: var(--brand-soft);
  border-left: 3px solid var(--brand-primary);
  border-radius: 4px var(--radius-card) var(--radius-card) 4px;
  padding: 12px 16px;
  font-size: 13px;
  color: #0369A1;
  line-height: 1.6;
  margin-bottom: 24px;
  max-width: 600px;
}

/* 7. 三条短信任点，带小勾 */
.hero-trust-list {
  display: flex;
  align-items: center;
  gap: 24px;
  flex-wrap: wrap;
}

.trust-item {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 13px;
  color: var(--text-muted);
  font-weight: 500;
}

.trust-icon {
  width: 16px;
  height: 16px;
  color: var(--brand-primary);
  flex-shrink: 0;
}

/* 右栏演示卡片 */
.hero-right {
  display: flex;
  justify-content: flex-end;
}

.demo-window-card {
  width: 100%;
  max-width: 460px;
  background-color: var(--bg-surface);
  border: 1px solid var(--border-ice);
  border-radius: var(--radius-demo);
  box-shadow: 0 16px 36px -4px rgba(15, 23, 42, 0.08), 0 0 1px 1px rgba(226, 232, 240, 0.5);
  overflow: hidden;
  position: relative;
  transition: transform 0.3s ease;
}

.demo-window-card:hover {
  transform: translateY(-2px);
}

.demo-header {
  height: 42px;
  background-color: #F8FAFC;
  border-bottom: 1px solid var(--border-light);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 16px;
}

.demo-dots {
  display: flex;
  gap: 6px;
}

.demo-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background-color: #E2E8F0;
}

.demo-dot:nth-child(1) { background-color: #CBD5E1; }
.demo-dot:nth-child(2) { background-color: #E2E8F0; }
.demo-dot:nth-child(3) { background-color: #F1F5F9; }

.demo-title {
  font-size: 12px;
  color: var(--text-light);
  font-family: var(--font-mono);
}

.demo-body {
  padding: 22px;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

/* 对话气泡 */
.chat-bubble-user {
  align-self: flex-end;
  background-color: #F1F5F9;
  border: 1px solid var(--border-light);
  color: var(--text-main);
  padding: 10px 14px;
  border-radius: 12px 12px 2px 12px;
  font-size: 13px;
  max-width: 88%;
  line-height: 1.5;
}

.chat-bubble-ai {
  align-self: flex-start;
  border-left: 3px solid var(--brand-primary);
  background-color: #FAFBFD;
  padding: 12px 14px;
  border-radius: 0 var(--radius-card) var(--radius-card) 0;
  font-size: 13px;
  line-height: 1.6;
  width: 100%;
}

.chat-bubble-ai .ai-role {
  font-size: 11px;
  font-weight: 700;
  color: var(--brand-primary);
  margin-bottom: 4px;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.code-embed-box {
  background-color: #0F172A;
  color: #E2E8F0;
  font-family: var(--font-mono);
  font-size: 11px;
  line-height: 1.5;
  border-radius: 8px;
  padding: 12px;
  margin-top: 10px;
  overflow-x: auto;
}

.code-embed-box .code-comment { color: #64748B; }
.code-embed-box .code-kw { color: #38BDF8; font-weight: 600; }
.code-embed-box .code-str { color: #A7F3D0; }
.code-embed-box .code-fn { color: #FDE047; }

.typing-indicator {
  display: flex;
  align-items: center;
  gap: 5px;
  padding-left: 6px;
  margin-top: 4px;
}

.typing-dot {
  width: 6px;
  height: 6px;
  background-color: var(--brand-primary);
  border-radius: 50%;
  opacity: 0.4;
  animation: typingBlink 1.4s infinite;
}

.typing-dot:nth-child(2) { animation-delay: 0.2s; }
.typing-dot:nth-child(3) { animation-delay: 0.4s; }

@keyframes typingBlink {
  0%, 100% { opacity: 0.2; transform: translateY(0); }
  50% { opacity: 1; transform: translateY(-2px); }
}

/* ========================================================
   能力区 (Capabilities Section)
   浅色底，上下细分割线。标题居中约 38px，说明居中且最宽约 720px。
   下面 6 张卡，桌面 3 列，间距 28px。
   每张卡白底、1px 浅灰边、圆角 12px、内边距 28px。
   上方 48px 圆角图标块用同一套线性图标，不要用表情符号。
   悬停上移约 4px，边框变为品牌色。标题 18px，说明 14px 灰色。
   窄于 968px 改为 2 列，窄于 640px 改为 1 列。
   ======================================================== */
.capabilities-section {
  background-color: #F8FAFC;
  border-top: 1px solid var(--border-light);
  border-bottom: 1px solid var(--border-light);
}

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

.cap-card {
  background-color: var(--bg-surface);
  border: 1px solid var(--border-ice);
  border-radius: var(--radius-card);
  padding: 28px;
  transition: all 0.25s cubic-bezier(0.16, 1, 0.3, 1);
  text-align: left;
  display: flex;
  flex-direction: column;
}

.cap-card:hover {
  transform: translateY(-4px);
  border-color: var(--brand-primary);
  box-shadow: var(--shadow-hover);
}

.cap-icon-box {
  width: 48px;
  height: 48px;
  border-radius: var(--radius-card);
  background-color: #F1F5F9;
  border: 1px solid var(--border-light);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
  color: var(--brand-primary);
  transition: all 0.2s ease;
}

.cap-card:hover .cap-icon-box {
  background-color: var(--brand-soft);
  border-color: var(--brand-border);
}

.cap-card-title {
  font-size: 18px;
  font-weight: 600;
  color: var(--text-main);
  margin-bottom: 10px;
  line-height: 1.35;
}

.cap-card-desc {
  font-size: 14px;
  color: var(--text-muted);
  line-height: 1.7;
}

/* ========================================================
   产品矩阵 (Product Matrix)
   白底。标题样式与能力区相同。
   4 张卡，桌面 4 列，间距 24px；窄于 1200px 改为 2 列，窄于 640px 改为 1 列。
   每张卡包含：小角标、名称、一行彩色副题、两行说明、底部分割线下的两个元信息。
   角标只用字重和文案区分角色，颜色不要超过品牌色加一个强调色。
   ======================================================== */
.matrix-section {
  background-color: var(--bg-surface);
}

.matrix-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}

.matrix-card {
  background-color: var(--bg-polar);
  border: 1px solid var(--border-ice);
  border-radius: var(--radius-card);
  padding: 24px;
  text-align: left;
  display: flex;
  flex-direction: column;
  position: relative;
  transition: all 0.25s ease;
}

.matrix-card:hover {
  border-color: var(--brand-border);
  box-shadow: var(--shadow-snow);
}

.matrix-badge-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 16px;
}

.matrix-badge {
  font-size: 11px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  padding: 2px 8px;
  border-radius: 4px;
  background-color: #FFFFFF;
  border: 1px solid var(--border-ice);
  color: var(--brand-primary);
}

.matrix-badge.accent {
  color: var(--accent-cyan);
}

.matrix-name {
  font-size: 20px;
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 4px;
}

.matrix-sub {
  font-size: 13px;
  color: var(--brand-primary);
  font-weight: 600;
  margin-bottom: 12px;
}

.matrix-desc {
  font-size: 13px;
  color: var(--text-muted);
  line-height: 1.6;
  margin-bottom: 20px;
  flex-grow: 1;
}

.matrix-meta-divider {
  border-top: 1px solid var(--border-light);
  padding-top: 14px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 12px;
  color: var(--text-light);
}

.matrix-meta-item {
  font-family: var(--font-mono);
}

/* ========================================================
   开发者区 (Developer Section)
   左右 1:1，间距 60px，窄于 1200px 改为上下堆叠。
   左：左对齐标题约 34px、一段说明、4 条带勾选项、一个描边按钮链到文档。
   右：深色代码面板，圆角 12px，等宽字体，含注释、关键字、字符串着色，展示最短可运行示例。
   ======================================================== */
.developer-section {
  background-color: #F8FAFC;
  border-top: 1px solid var(--border-light);
  border-bottom: 1px solid var(--border-light);
}

.developer-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
}

.dev-left {
  text-align: left;
}

.dev-title {
  font-size: 34px;
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--text-deboss);
  line-height: 1.25;
  margin-bottom: 16px;
  text-shadow: 0 1px 0 #FFFFFF;
}

.dev-desc {
  font-size: 15px;
  color: var(--text-muted);
  line-height: 1.7;
  margin-bottom: 24px;
}

.dev-checklist {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 12px;
  margin-bottom: 30px;
}

.dev-check-item {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 14px;
  color: var(--text-main);
}

.dev-check-icon {
  width: 18px;
  height: 18px;
  color: var(--brand-primary);
  flex-shrink: 0;
}

.dev-right {
  width: 100%;
}

.code-panel {
  background-color: #0F172A;
  border-radius: var(--radius-card);
  border: 1px solid #1E293B;
  box-shadow: 0 20px 40px -8px rgba(15, 23, 42, 0.16);
  overflow: hidden;
}

.code-panel-topbar {
  height: 40px;
  background-color: #1E293B;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 16px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.05);
}

.code-lang-label {
  font-size: 12px;
  color: #94A3B8;
  font-family: var(--font-mono);
}

.code-content-pre {
  padding: 24px;
  font-family: var(--font-mono);
  font-size: 13px;
  line-height: 1.7;
  color: #F8FAFC;
  overflow-x: auto;
}

/* ========================================================
   动态区 (News & Updates Section)
   标题行两端对齐，左侧标题，右侧「查看全部」。
   下面一张通栏列表，不要再拆成卡片网格。
   每行：小标签、标题、日期。标签最多两种。
   悬停只改变行背景。窄于 640px 时日期换到标题下方。
   ======================================================== */
.news-section {
  background-color: var(--bg-surface);
}

.news-header-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 32px;
}

.news-section-title {
  font-size: 28px;
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--text-deboss);
}

.news-view-all {
  font-size: 14px;
  color: var(--brand-primary);
  font-weight: 500;
  display: inline-flex;
  align-items: center;
  gap: 4px;
}

.news-view-all:hover {
  color: var(--brand-hover);
}

.news-table-card {
  background-color: var(--bg-surface);
  border: 1px solid var(--border-ice);
  border-radius: var(--radius-card);
  overflow: hidden;
}

.news-item-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 20px 24px;
  border-bottom: 1px solid var(--border-light);
  transition: background-color 0.15s ease;
  cursor: pointer;
}

.news-item-row:last-child {
  border-bottom: none;
}

.news-item-row:hover {
  background-color: #F8FAFC;
}

.news-left-content {
  display: flex;
  align-items: center;
  gap: 16px;
  flex: 1;
  min-width: 0;
}

/* 标签最多两种：发布与研究 */
.news-tag {
  font-size: 11px;
  font-weight: 600;
  padding: 3px 8px;
  border-radius: 4px;
  white-space: nowrap;
}

.news-tag.tag-release {
  background-color: var(--brand-soft);
  color: var(--brand-primary);
}

.news-tag.tag-research {
  background-color: rgba(13, 148, 136, 0.08);
  color: var(--accent-cyan);
}

.news-row-title {
  font-size: 15px;
  color: var(--text-main);
  font-weight: 500;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.news-date {
  font-size: 13px;
  color: var(--text-light);
  font-family: var(--font-mono);
  white-space: nowrap;
  margin-left: 16px;
}

/* ========================================================
   下载区 (Download & Access Section)
   居中。标题、一句平台说明，然后主按钮 + 描边次按钮。
   窄于 640px 时按钮纵向排列并保持居中，不要拉成全宽。
   ======================================================== */
.download-section {
  background-color: #F8FAFC;
  border-top: 1px solid var(--border-light);
  text-align: center;
}

.download-inner {
  max-width: 640px;
  margin: 0 auto;
}

.download-title {
  font-size: 32px;
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--text-deboss);
  margin-bottom: 12px;
}

.download-subtitle {
  font-size: 15px;
  color: var(--text-muted);
  line-height: 1.7;
  margin-bottom: 32px;
}

.download-btn-group {
  display: inline-flex;
  align-items: center;
  gap: 16px;
}

/* ========================================================
   合理图片展示与画廊模块 (Gallery Showcase)
   展示 1.webp - 9.webp，图片带规范宽高与alt
   ======================================================== */
.gallery-section {
  background-color: var(--bg-surface);
  border-top: 1px solid var(--border-light);
}

.gallery-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.gallery-item {
  background-color: var(--bg-polar);
  border: 1px solid var(--border-ice);
  border-radius: var(--radius-card);
  overflow: hidden;
  transition: all 0.25s ease;
}

.gallery-item:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-snow);
  border-color: var(--brand-border);
}

.gallery-img {
  width: 100%;
  height: 220px;
  object-fit: cover;
  display: block;
}

.gallery-caption {
  padding: 14px 18px;
  font-size: 13px;
  color: var(--text-muted);
  border-top: 1px solid var(--border-light);
  background-color: #FFFFFF;
}

/* ========================================================
   页脚 (Footer)
   白底，顶部分割线。四列，比例约 2:1:1:1。
   第一列是字标和两行品牌说明；其余三列是分组链接（产品、资源、关于）。
   底部一条版权与备案。不要在页脚后再加一排关键词链接。
   窄于 968px 改为 2 列，窄于 640px 改为 1 列。
   ======================================================== */
.footer-section {
  background-color: var(--bg-surface);
  border-top: 1px solid var(--border-light);
  padding-top: 72px;
  padding-bottom: 40px;
  position: relative;
  z-index: 2;
}

.footer-top-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 48px;
  margin-bottom: 56px;
  text-align: left;
}

.footer-brand-col {
  display: flex;
  flex-direction: column;
}

.footer-brand-header {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 16px;
}

.footer-logo-img {
  width: 28px;
  height: 28px;
  border-radius: var(--radius-logo);
  border: 1px solid var(--border-ice);
}

.footer-brand-name {
  font-size: 18px;
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--text-deboss);
}

.footer-desc-lines {
  font-size: 13px;
  color: var(--text-muted);
  line-height: 1.7;
  max-width: 320px;
}

.footer-col-title {
  font-size: 14px;
  font-weight: 600;
  color: var(--text-main);
  margin-bottom: 18px;
}

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

.footer-link-item a {
  font-size: 13px;
  color: var(--text-muted);
}

.footer-link-item a:hover {
  color: var(--brand-primary);
}

.footer-bottom-bar {
  border-top: 1px solid var(--border-light);
  padding-top: 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 12px;
  color: var(--text-light);
  flex-wrap: wrap;
  gap: 12px;
}

/* ========================================================
   子页面专用组件：Web 对话工作台 & 帮助中心知识库
   ======================================================== */
/* Web 入口工作台样式 */
.chat-workspace-card {
  background-color: var(--bg-surface);
  border: 1px solid var(--border-ice);
  border-radius: var(--radius-demo);
  box-shadow: 0 16px 40px -8px rgba(15, 23, 42, 0.06);
  padding: 32px;
  margin-bottom: 40px;
}

.chat-input-container {
  display: flex;
  gap: 12px;
  margin-top: 20px;
  position: relative;
}

.chat-input-field {
  flex: 1;
  height: 52px;
  border: 1px solid var(--border-ice);
  border-radius: var(--radius-btn);
  padding: 0 18px;
  font-size: 14px;
  background-color: #FAFBFD;
  outline: none;
  transition: border-color 0.2s ease;
}

.chat-input-field:focus {
  border-color: var(--brand-primary);
  background-color: #FFFFFF;
}

.prompt-tags-cloud {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
  margin-top: 16px;
}

.prompt-tag-btn {
  font-size: 12px;
  background-color: #F1F5F9;
  border: 1px solid var(--border-light);
  color: var(--text-muted);
  border-radius: var(--radius-pill);
  padding: 6px 14px;
  cursor: pointer;
  transition: all 0.2s ease;
}

.prompt-tag-btn:hover {
  background-color: var(--brand-soft);
  color: var(--brand-primary);
  border-color: var(--brand-border);
}

/* 帮助中心折叠面板与教程步骤 */
.help-grid-layout {
  display: grid;
  grid-template-columns: 280px 1fr;
  gap: 40px;
  text-align: left;
}

.help-sidebar {
  background-color: var(--bg-surface);
  border: 1px solid var(--border-ice);
  border-radius: var(--radius-card);
  padding: 24px;
  height: fit-content;
}

.help-menu-group-title {
  font-size: 12px;
  font-weight: 700;
  text-transform: uppercase;
  color: var(--text-light);
  letter-spacing: 0.05em;
  margin-bottom: 12px;
}

.help-menu-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 8px;
  margin-bottom: 24px;
}

.help-menu-item a {
  display: block;
  font-size: 14px;
  color: var(--text-muted);
  padding: 6px 12px;
  border-radius: 6px;
  transition: all 0.15s ease;
}

.help-menu-item a:hover,
.help-menu-item.active a {
  background-color: var(--brand-soft);
  color: var(--brand-primary);
  font-weight: 500;
}

.help-content-card {
  background-color: var(--bg-surface);
  border: 1px solid var(--border-ice);
  border-radius: var(--radius-card);
  padding: 36px;
  margin-bottom: 32px;
}

.help-content-card h2 {
  font-size: 22px;
  font-weight: 700;
  margin-bottom: 16px;
  color: var(--text-deboss);
}

.help-content-card p {
  font-size: 14px;
  color: var(--text-muted);
  line-height: 1.8;
  margin-bottom: 18px;
}

.faq-accordion {
  display: flex;
  flex-direction: column;
  gap: 14px;
  margin-top: 20px;
}

.faq-item {
  border: 1px solid var(--border-ice);
  border-radius: var(--radius-card);
  padding: 16px 20px;
  background-color: #FAFBFD;
}

.faq-question {
  font-size: 15px;
  font-weight: 600;
  color: var(--text-main);
  margin-bottom: 8px;
}

.faq-answer {
  font-size: 14px;
  color: var(--text-muted);
  line-height: 1.7;
}

/* ========================================================
   响应式断点系统 (Strict Breakpoints)
   1. 窄于 1200px: 矩阵变为2列，开发者区上下堆叠
   2. 窄于 968px: 收起导航并提供汉堡菜单，首屏单列，能力区2列，页脚2列
   3. 窄于 640px: 能力区1列，矩阵1列，动态区日期换行，下载区按钮居中纵排，页脚1列
   ======================================================== */

/* 断点 1：窄于 1200px */
@media (max-width: 1200px) {
  .matrix-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .developer-grid {
    grid-template-columns: 1fr;
    gap: 40px;
  }

  .help-grid-layout {
    grid-template-columns: 1fr;
  }

  .gallery-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

/* 断点 2：窄于 968px (平板与中小屏) */
@media (max-width: 968px) {
  .container {
    padding-left: 32px;
    padding-right: 32px;
  }

  .section-wrapper {
    padding-top: 72px;
    padding-bottom: 72px;
  }

  /* 导航收起中间链接并提供汉堡菜单 */
  .nav-links-center {
    display: none;
  }

  .mobile-menu-btn {
    display: inline-flex;
  }

  /* 首屏改为单列，演示卡放在文案下面 */
  .hero-section {
    padding-top: 110px;
    min-height: auto;
  }

  .hero-grid {
    grid-template-columns: 1fr;
    gap: 48px;
  }

  .hero-right {
    justify-content: flex-start;
  }

  .demo-window-card {
    max-width: 100%;
  }

  /* 能力区改为 2 列 */
  .capabilities-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: 20px;
  }

  /* 页脚改为 2 列 */
  .footer-top-grid {
    grid-template-columns: 1fr 1fr;
    gap: 36px;
  }
}

/* 断点 3：窄于 640px (手机屏) */
@media (max-width: 640px) {
  .container {
    padding-left: 16px;
    padding-right: 16px;
  }

  .section-wrapper {
    padding-top: 56px;
    padding-bottom: 56px;
  }

  .hero-product-name {
    font-size: 32px;
  }

  .hero-proposition {
    font-size: 20px;
  }

  .section-title-center {
    font-size: 28px;
  }

  .dev-title {
    font-size: 26px;
  }

  /* 能力区改为 1 列 */
  .capabilities-grid {
    grid-template-columns: 1fr;
  }

  /* 产品矩阵改为 1 列 */
  .matrix-grid {
    grid-template-columns: 1fr;
  }

  .gallery-grid {
    grid-template-columns: 1fr;
  }

  /* 动态区：日期换到标题下方 */
  .news-item-row {
    flex-direction: column;
    align-items: flex-start;
    gap: 8px;
  }

  .news-date {
    margin-left: 0;
  }

  /* 下载区按钮纵向排列并保持居中，不要拉成全宽 */
  .download-btn-group {
    flex-direction: column;
    width: auto;
    margin: 0 auto;
  }

  .download-btn-group .btn-primary-solid,
  .download-btn-group .btn-outline-secondary {
    width: auto;
    min-width: 200px;
  }

  /* 页脚改为 1 列 */
  .footer-top-grid {
    grid-template-columns: 1fr;
    gap: 28px;
  }

  .footer-bottom-bar {
    flex-direction: column;
    align-items: flex-start;
  }
}

/* scroll-perf: keep first screen painted, defer the rest, drop blur on small screens */
main > section:not(:first-of-type) {
  content-visibility: auto;
  contain-intrinsic-size: auto 720px;
}
img {
  max-width: 100%;
}
@media (max-width: 968px) {
  .site-header,
  .nav-drawer,
  header {
    backdrop-filter: none !important;
    -webkit-backdrop-filter: none !important;
  }
}
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}