/* ===== 杭州立纬科技官网 主样式表（v2 视觉升级） ===== */

:root {
  /* === 主色系 - 冷调青灰蓝（工业级 / 精密感） === */
  --primary-700: #1B3454;
  --primary-600: #23456E;
  --primary-500: #2E5A8C;
  --primary-300: #5C9AC8;
  --primary-200: #8ABBD9;
  --primary-50:  #D5E7F3;

  /* === 强调色 - 铜暖（呼应 logo 橙但更沉稳） === */
  --accent-700: #C63816;
  --accent-600: #E2481C;
  --accent-500: #F06532;
  --accent-400: #FF834D;
  --accent-300: #FFA875;
  --accent-100: #FFE5D4;
  --accent-50:  #FFF3EA;

  /* === 中性色 - 偏冷灰（克制、专业） === */
  --gray-900: #141B26;
  --gray-800: #1F2937;
  --gray-700: #374151;
  --gray-600: #4B5563;
  --gray-500: #6B7280;
  --gray-400: #94A3B8;
  --gray-300: #CBD5E1;
  --gray-200: #E2E8F0;
  --gray-100: #F1F5F9;
  --gray-50:  #F8FAFC;

  /* === 功能色 === */
  --success: #0D9488;

  /* === 布局 === */
  --max-width: 1280px;
  --nav-height: 76px;
  --section-padding-y: 140px;
  --section-padding-y-mobile: 72px;

  /* === 圆角（更克制的大圆角 + 一致的小圆角） === */
  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 22px;
  --radius-xl: 36px;
  --radius-full: 9999px;

  /* === 阴影 - 多层、更柔和（真实深度感） === */
  --shadow-sm: 0 2px 6px rgba(15, 29, 50, 0.06), 0 1px 2px rgba(15, 29, 50, 0.04);
  --shadow-md: 0 6px 20px rgba(15, 29, 50, 0.08), 0 2px 6px rgba(15, 29, 50, 0.05);
  --shadow-lg: 0 16px 40px rgba(15, 29, 50, 0.10), 0 6px 16px rgba(15, 29, 50, 0.06);
  --shadow-xl: 0 28px 64px rgba(15, 29, 50, 0.14), 0 12px 28px rgba(15, 29, 50, 0.08);

  /* === 渐变 === */
  --gradient-accent: linear-gradient(135deg, #E2481C 0%, #F06532 55%, #FF834D 100%);
  --gradient-hero: linear-gradient(160deg, #DCE9F4 0%, #E5EFF7 35%, #F0F6FB 70%, #FFFFFF 100%);
  --gradient-glass-light: linear-gradient(135deg, rgba(255,255,255,0.70) 0%, rgba(255,255,255,0.40) 100%);
  --gradient-top-accent: linear-gradient(90deg, transparent 0%, rgba(240, 101, 50, 0.55) 50%, transparent 100%);
  --gradient-divider: linear-gradient(90deg, transparent 0%, var(--gray-200) 20%, var(--gray-200) 80%, transparent 100%);

  /* === 浅色层次专用 === */
  --surface-soft: #E5EFF7;       /* section-light 底色：清爽浅蓝，与纯白一眼可辨 */
  --border-subtle: var(--gray-200);
  --card-shadow: 0 4px 16px rgba(15, 29, 50, 0.06), 0 1px 3px rgba(15, 29, 50, 0.04);
  --card-shadow-hover: 0 14px 36px rgba(15, 29, 50, 0.10), 0 4px 12px rgba(15, 29, 50, 0.06);

  /* === 字体 === */
  --font-display: 'Noto Serif SC', 'Songti SC', 'SimSun', serif;
  --font-body: 'Noto Sans SC', -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Microsoft YaHei', sans-serif;

  /* === 动效节奏（克制） === */
  --ease-out: cubic-bezier(0.22, 1, 0.36, 1);
  --dur-fast: 180ms;
  --dur-base: 320ms;
  --dur-slow: 600ms;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.7;
  color: var(--gray-700);
  background-color: #ffffff;
  background: #ffffff;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
  text-wrap: pretty;
  font-feature-settings: 'palt' 1;
}

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

a {
  color: inherit;
  text-decoration: none;
}

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

/* 全站悬浮回顶按钮 */
.back-to-top {
  position: fixed;
  right: clamp(20px, 3vw, 44px);
  bottom: 88px;
  z-index: 900;
  width: 50px;
  height: 50px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--primary-700);
  background: rgba(255, 255, 255, 0.68);
  border: 1px solid rgba(255, 255, 255, 0.82);
  border-radius: 50%;
  box-shadow: 0 8px 24px rgba(15, 29, 50, 0.14), inset 0 0 0 1px rgba(35, 69, 110, 0.08);
  -webkit-backdrop-filter: blur(14px) saturate(135%);
  backdrop-filter: blur(14px) saturate(135%);
  opacity: 0;
  pointer-events: none;
  transform: translateY(12px) scale(0.92);
  transition: opacity var(--dur-base) var(--ease-out), transform var(--dur-base) var(--ease-out), background var(--dur-fast) ease, color var(--dur-fast) ease;
}

.back-to-top.is-visible {
  opacity: 1;
  pointer-events: auto;
  transform: translateY(0) scale(1);
}

.back-to-top:hover {
  color: #fff;
  background: rgba(226, 72, 28, 0.86);
  border-color: rgba(255, 255, 255, 0.72);
  transform: translateY(-3px) scale(1.03);
}

.back-to-top:focus-visible {
  outline: 3px solid rgba(240, 101, 50, 0.30);
  outline-offset: 3px;
}

.back-to-top svg {
  width: 22px;
  height: 22px;
  fill: none;
  stroke: currentColor;
  stroke-width: 1.8;
  stroke-linecap: round;
  stroke-linejoin: round;
}

@media (max-width: 600px) {
  .back-to-top {
    right: 16px;
    bottom: calc(72px + env(safe-area-inset-bottom, 0px));
    width: 44px;
    height: 44px;
  }

  .back-to-top svg {
    width: 20px;
    height: 20px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .back-to-top {
    transition: none;
  }
}

.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 48px;
  position: relative;
}

@media (max-width: 900px) {
  .container { padding: 0 28px; }
}

@media (max-width: 560px) {
  .container { padding: 0 20px; }
}

/* ===== 通用章节样式 ===== */

.section {
  padding: var(--section-padding-y) 0;
  position: relative;
  overflow: hidden;
}

/* 章节外沿统一：章节最后一块内容不再叠加自身的底部留白。
   这样各章节之间只由 section 的统一上下 padding 决定间距。 */
.section > .container > :last-child {
  margin-bottom: 0;
}

.section-dark {
  background-color: #ffffff;
  color: var(--gray-800);
  position: relative;
}

.section-dark::after {
  content: '';
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(30, 60, 100, 0.06) 1px, transparent 1px),
    linear-gradient(90deg, rgba(30, 60, 100, 0.06) 1px, transparent 1px);
  background-size: 80px 80px;
  mask-image: radial-gradient(ellipse 85% 70% at 50% 50%, black 0%, transparent 80%);
  -webkit-mask-image: radial-gradient(ellipse 85% 70% at 50% 50%, black 0%, transparent 80%);
  pointer-events: none;
  z-index: 0;
}

.section-dark > * {
  position: relative;
  z-index: 1;
}

.section-light {
  background-color: var(--surface-soft);
  position: relative;
}

.section-light::after {
  content: '';
  position: absolute;
  inset: 0;
  background-image:
    radial-gradient(circle at 1px 1px, rgba(30, 60, 100, 0.10) 1px, transparent 0);
  background-size: 24px 24px;
  mask-image: radial-gradient(ellipse 90% 80% at 50% 50%, black 0%, transparent 85%);
  -webkit-mask-image: radial-gradient(ellipse 90% 80% at 50% 50%, black 0%, transparent 85%);
  pointer-events: none;
  z-index: 0;
}

.section-light > * {
  position: relative;
  z-index: 1;
}

/* 全站分界线统一收敛到「内容 → 页脚」交界处一条。
   页面内部 section 间不再自动加线。
   各页面底部 → 页脚的线由各自页面样式单独控制。

   历史背景：此前用 section-light + section-dark 自动加交界线，
   导致公司介绍页等出现多条内部线，不符合最终设计。
   保留注释和规则结构以便回溯。 */
.section-light + .section-dark,
.section-dark + .section-light {
  position: relative;
}

.section-light + .section-dark::before,
.section-dark + .section-light::before {
  content: none;
}



.section-label {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 2.5px;
  text-transform: none;
  margin-bottom: 20px;
  font-feature-settings: 'palt' 1;
}

.section-label::before {
  content: '';
  display: inline-block;
  width: 28px;
  height: 1px;
  background: currentColor;
  opacity: 0.5;
}

.section-label-dark {
  color: var(--accent-600);
}

.section-label-light {
  color: var(--accent-600);
}

/* 内页章节编号：公司介绍、业务体系、场景方案共用同一套排版 */
.section-index-heading {
  display: inline-flex;
  align-items: center;
  gap: 14px;
  margin-bottom: 22px;
  color: var(--gray-700);
  letter-spacing: normal;
}

.section-label.section-index-heading::before {
  display: none;
}

.section-index-number {
  flex: none;
  min-width: 42px;
  color: var(--accent-600);
  font-family: var(--font-display);
  font-size: clamp(30px, 3vw, 40px);
  font-weight: 700;
  font-variant-numeric: tabular-nums;
  letter-spacing: -0.04em;
  line-height: 1;
}

.section-index-rule {
  flex: none;
  width: 32px;
  height: 1px;
  background: var(--accent-500);
  opacity: 0.55;
}

.section-index-title {
  margin: 0;
  color: var(--gray-700);
  font-family: var(--font-body);
  font-size: 14px;
  font-weight: 600;
  letter-spacing: 0.16em;
  line-height: 1.3;
}

@media (max-width: 600px) {
  .section-index-heading {
    gap: 10px;
    margin-bottom: 18px;
  }

  .section-index-number {
    min-width: 36px;
    font-size: 28px;
  }

  .section-index-rule {
    width: 24px;
  }

  .section-index-title {
    font-size: 13px;
    letter-spacing: 0.12em;
  }
}

/* 章节标题 —— 更大对比、更细的中宫 */
.section-title {
  font-family: var(--font-display);
  font-size: clamp(30px, 3.8vw, 48px);
  font-weight: 700;
  line-height: 1.2;
  margin-bottom: 18px;
  letter-spacing: -0.015em;
  color: var(--gray-900);
}

.section-dark .section-title {
  color: var(--gray-900);
}

.section-subtitle {
  font-size: clamp(15px, 1.2vw, 17px);
  line-height: 1.8;
  max-width: 620px;
  color: var(--gray-500);
  font-weight: 400;
}

.section-dark .section-subtitle {
  color: var(--gray-500);
  opacity: 1;
}

.section-header {
  margin-bottom: 72px;
}

.section-header.text-center .section-subtitle {
  margin-left: auto;
  margin-right: auto;
}

@media (max-width: 768px) {
  .section {
    padding: var(--section-padding-y-mobile) 0;
  }
  .section-header {
    margin-bottom: 48px;
  }
}

/* ===== 按钮样式 ===== */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  padding: 14px 32px;
  font-size: 15px;
  font-weight: 600;
  border-radius: var(--radius-sm);
  transition: all var(--dur-base) var(--ease-out);
  white-space: nowrap;
  position: relative;
  overflow: hidden;
  letter-spacing: 0.02em;
}

.btn-primary {
  background: var(--gradient-accent);
  color: #ffffff;
  box-shadow: 0 6px 18px rgba(240, 101, 50, 0.30), 0 2px 6px rgba(240, 101, 50, 0.18);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 10px 28px rgba(240, 101, 50, 0.38), 0 4px 10px rgba(240, 101, 50, 0.22);
}

.btn-primary:active {
  transform: translateY(0);
}

.btn-outline {
  background: rgba(255, 255, 255, 0.65);
  color: var(--gray-800);
  border: 1.5px solid var(--gray-200);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
}

.btn-outline:hover {
  border-color: var(--gray-400);
  background: #ffffff;
  color: var(--gray-900);
}

/* ===== 卡片通用样式 ===== */

.card {
  background: #ffffff;
  border-radius: var(--radius-lg);
  box-shadow: var(--card-shadow);
  border: 1px solid var(--border-subtle);
  transition: all var(--dur-base) var(--ease-out);
  overflow: hidden;
  position: relative;
}

.card::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 2px;
  background: var(--gradient-top-accent);
  transition: all var(--dur-slow) var(--ease-out);
  opacity: 0;
  z-index: 2;
}

.card::after {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 1px;
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.8), rgba(255, 255, 255, 0));
  pointer-events: none;
  z-index: 1;
}

.card:hover {
  transform: translateY(-4px);
  box-shadow: var(--card-shadow-hover);
  border-color: var(--gray-300);
}

.card:hover::before {
  opacity: 1;
}

.card-dark {
  background: var(--gradient-glass-light);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  box-shadow: var(--card-shadow);
  position: relative;
  overflow: hidden;
}

.card-dark::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 2px;
  background: var(--gradient-top-accent);
  opacity: 0;
  transition: opacity var(--dur-slow) var(--ease-out);
  z-index: 2;
}

.card-dark:hover {
  background: #ffffff;
  border-color: var(--gray-300);
  box-shadow: var(--card-shadow-hover);
}

.card-dark:hover::before {
  opacity: 1;
}

/* ===== 动画 ===== */

@keyframes fadeInUp {
  from { opacity: 0; transform: translateY(24px); }
  to   { opacity: 1; transform: translateY(0); }
}

@keyframes fadeIn {
  from { opacity: 0; }
  to   { opacity: 1; }
}

@keyframes slideInLeft {
  from { opacity: 0; transform: translateX(-32px); }
  to   { opacity: 1; transform: translateX(0); }
}

@keyframes float {
  0%, 100% { transform: translateY(0); }
  50%      { transform: translateY(-8px); }
}

.animate-float {
  animation: float 6s ease-in-out infinite;
}

/* ===== 滚动揭示 ===== */

.reveal {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity var(--dur-slow) var(--ease-out),
              transform var(--dur-slow) var(--ease-out);
}

.reveal.is-visible {
  opacity: 1;
  transform: translateY(0);
}

/* ===== 辅助类 ===== */

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

/* 仅供读屏与搜索引擎的页面级标题：视觉不可见，但保留在无障碍树中。
   内页可见的页名是面包屑，页面级 h1 用该类承载，因此不改变现有视觉设计。 */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  clip-path: inset(50%);
  white-space: nowrap;
  border: 0;
}

.text-gradient {
  background: var(--gradient-accent);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* 内页章节导航：仅在手机向下滚动后显示，保持单行横向浏览。 */
.page-jump-nav {
  display: none;
  align-items: center;
  justify-content: flex-start;
  gap: 8px;
  overflow-x: auto;
  scrollbar-width: none;
  -webkit-overflow-scrolling: touch;
}

.page-jump-nav::-webkit-scrollbar {
  display: none;
}

.page-jump-nav a {
  flex: 0 0 auto;
  padding: 9px 16px;
  color: var(--gray-700);
  background: rgba(255, 255, 255, 0.92);
  border: 1px solid var(--gray-200);
  border-radius: var(--radius-full);
  box-shadow: 0 2px 8px rgba(15, 29, 50, 0.05);
  font-size: 13px;
  font-weight: 600;
  text-decoration: none;
  white-space: nowrap;
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
}

.page-jump-nav a:hover {
  color: var(--accent-700);
  border-color: var(--accent-200);
}

.page-jump-nav a.page-jump-nav-active {
  color: #ffffff;
  background: var(--gradient-accent);
  border-color: transparent;
  box-shadow: 0 4px 12px rgba(240, 101, 50, 0.26);
}

.page-jump-nav a:focus-visible {
  outline: 3px solid rgba(61, 122, 184, 0.45);
  outline-offset: 2px;
}

@media (max-width: 600px) {
  .page-jump-nav {
    position: fixed;
    top: calc(var(--nav-height) + 8px);
    left: 12px;
    right: 12px;
    z-index: 80;
    display: flex;
    justify-content: safe center;
    width: auto;
    padding: 10px;
    scroll-padding-inline: 10px;
    background: rgba(247, 250, 252, 0.96);
    border: 1px solid rgba(15, 29, 50, 0.10);
    border-radius: var(--radius-md);
    box-shadow: 0 8px 24px rgba(15, 29, 50, 0.10);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    opacity: 0;
    visibility: hidden;
    pointer-events: none;
    transform: translateY(-10px);
    transition: opacity var(--dur-fast) var(--ease-out),
                transform var(--dur-fast) var(--ease-out),
                visibility var(--dur-fast) var(--ease-out),
                top var(--dur-fast) var(--ease-out);
  }

  .page-jump-nav-visible {
    opacity: 1;
    visibility: visible;
    pointer-events: auto;
    transform: translateY(0);
  }

  .mobile-header-hidden .page-jump-nav {
    top: max(8px, env(safe-area-inset-top));
  }

  .page-jump-nav a {
    min-height: 40px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 8px 14px;
    font-size: 13px;
  }
}

/* ===== 无障碍：减少动效 ===== */

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
    scroll-behavior: auto !important;
  }
  .reveal {
    opacity: 1;
    transform: none;
  }
}