/* ==========================================================================
   全局核心变量设定 (对标 lihi.io 极净明亮 SaaS 风格)
   ========================================================================== */
:root {
  --bg: #f8fafc;                  
  --surface: rgba(255, 255, 255, 0.85); 
  --surface-solid: #ffffff;       
  --text: #0f172a;                
  --muted: #475569;               
  --line: #e2e8f0;                
  
  --blue: #2563eb;                
  --blue-dark: #1d4ed8;
  --blue-glow: rgba(37, 99, 235, 0.08);
  --violet: #7c3aed;
  --orange: #ea580c;
  --green: #10b981;
  --cyan: #06b6d4;
  
  --shadow-lg: 0 25px 50px -12px rgba(15, 23, 42, 0.06);
  --shadow-md: 0 12px 24px -4px rgba(15, 23, 42, 0.04);
  --radius-xl: 20px;
  --radius-lg: 16px;
  --radius-md: 12px;
  --container: 1180px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "PingFang SC", sans-serif;
  color: var(--text);
  background: var(--bg);
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

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

ul {
  margin: 0;
  padding: 0;
  list-style: none;
}

p, h1, h2, h3, h4 {
  margin: 0;
}

.container {
  width: min(var(--container), calc(100% - 40px));
  margin: 0 auto;
}

/* ==========================================================================
   头部导航栏
   ========================================================================== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: blur(20px);
  background: rgba(248, 250, 252, 0.85);
  border-bottom: 1px solid var(--line);
}

.nav-shell {
  min-height: 76px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
}

.brand img {
  width: 36px;
  height: 36px;
}

.brand strong {
  display: block;
  font-size: 19px;
  font-weight: 700;
  color: var(--text);
  letter-spacing: -0.5px;
}

.brand span {
  display: block;
  font-size: 10px;
  font-weight: 600;
  color: var(--blue);
  letter-spacing: 0.05em;
  text-transform: uppercase;
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 6px;
}

.nav-link {
  padding: 8px 16px;
  color: var(--muted);
  font-size: 14px;
  font-weight: 500;
  border-radius: 999px;
  transition: all 0.2s ease;
}

.nav-link:hover, .nav-link.is-active {
  color: var(--blue);
  background: rgba(37, 99, 235, 0.06);
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 40px;
  padding: 0 20px;
  border-radius: 8px;
  font-size: 14px;
  font-weight: 600;
  transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
  cursor: pointer;
}

.button-primary {
  background: var(--blue);
  color: #ffffff;
  box-shadow: 0 4px 12px rgba(37, 99, 235, 0.2);
}

.button-primary:hover {
  transform: translateY(-1px);
  background: var(--blue-dark);
  box-shadow: 0 6px 18px rgba(37, 99, 235, 0.3);
}

/* ==========================================================================
   首屏 (Hero Section) 样式
   ========================================================================== */
.hero-section {
  padding: 80px 0;
  position: relative;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.05fr 0.95fr;
  align-items: center;
  gap: 50px;
}

.hero-banner h1 {
  font-size: clamp(34px, 4.2vw, 48px);
  font-weight: 800;
  line-height: 1.2;
  color: var(--text);
  letter-spacing: -1px;
  margin-bottom: 20px;
}

.hero-banner h1 span {
  color: var(--blue);
  background: linear-gradient(135deg, var(--blue), #06b6d4);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-desc {
  font-size: 16px;
  line-height: 1.65;
  color: var(--muted);
  margin-bottom: 30px;
}

.hero-stats-strip {
  display: flex;
  gap: 40px;
  margin-top: 36px;
  padding-top: 24px;
  border-top: 1px solid var(--line);
}

.stat-item strong {
  display: block;
  font-size: 28px;
  color: var(--text);
  font-weight: 700;
}

.stat-item strong span {
  color: var(--blue);
}

.stat-item .label {
  display: block;
  margin-top: 4px;
  font-size: 13px;
  color: var(--muted);
}

/* 右侧真实白底图片高阶降噪裁剪外壳 */
.hero-visual {
  position: relative;
  width: 100%;
}

.hero-visual-mesh {
  position: absolute;
  width: 110%;
  height: 110%;
  background: radial-gradient(circle at center, rgba(37, 99, 235, 0.05) 0%, transparent 70%);
  z-index: 1;
  pointer-events: none;
}

.saas-browser-window {
  position: relative;
  z-index: 2;
  width: 100%;
  background: #ffffff;
  border: 1px solid #cbd5e1;
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-lg);
  overflow: hidden;
  animation: ssaasFloating 6s ease-in-out infinite;
}

.browser-header {
  background: #f8fafc;
  padding: 12px 16px;
  display: flex;
  align-items: center;
  border-bottom: 1px solid #e2e8f0;
}

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

.browser-dots span {
  width: 8px;
  height: 8px;
  border-radius: 50%;
}
.dot-red { background: #ff5f56; }
.dot-yellow { background: #ffbd2e; }
.dot-green { background: #27c93f; }

.browser-address-bar {
  margin-left: 20px;
  background: #ffffff;
  border: 1px solid #e2e8f0;
  border-radius: 6px;
  padding: 4px 16px;
  font-size: 11px;
  color: #64748b;
  font-family: monospace;
  display: flex;
  align-items: center;
  gap: 6px;
  flex-grow: 0.8;
}

.browser-content {
  position: relative;
  width: 100%;
  height: 320px;
  background: #ffffff;
  overflow: hidden;
}

.saas-dashboard-img {
  width: 100%;
  height: 520px;
  object-fit: cover;
  object-position: top center;
  display: block;
}

.browser-bottom-fade {
  position: absolute;
  bottom: 0;
  left: 0;
  width: 100%;
  height: 80px;
  background: linear-gradient(to bottom, transparent, rgba(255, 255, 255, 0.95) 85%, #ffffff);
  pointer-events: none;
  z-index: 3;
}

/* ==========================================================================
   模块通用样式与业务矩阵
   ========================================================================== */
.section {
  padding: 90px 0;
}

.section-alt {
  background: #f1f5f9; /* 浅灰交替色块，提供视觉停顿感 */
}

.section-heading {
  text-align: center;
  max-width: 650px;
  margin: 0 auto 56px;
}

.section-heading h2 {
  font-size: 32px;
  font-weight: 700;
  margin-bottom: 14px;
  color: var(--text);
  letter-spacing: -0.5px;
}

.section-heading p {
  color: var(--muted);
  font-size: 15px;
  line-height: 1.5;
}

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

.system-card {
  background: var(--surface-solid);
  border: 1px solid var(--line);
  border-radius: var(--radius-xl);
  padding: 36px;
  box-shadow: var(--shadow-md);
  transition: all 0.3s ease;
}

.system-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-lg);
}

.system-icon {
  width: 44px;
  height: 44px;
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 20px;
  margin-bottom: 20px;
}
.icon-orange { background: rgba(234, 88, 12, 0.08); color: var(--orange); }
.icon-green { background: rgba(16, 185, 129, 0.08); color: var(--green); }
.icon-blue { background: rgba(37, 99, 235, 0.08); color: var(--blue); }

.system-card h3 {
  font-size: 20px;
  font-weight: 700;
  margin-bottom: 12px;
}

.system-card p {
  color: var(--muted);
  font-size: 14px;
  line-height: 1.6;
  margin-bottom: 24px;
  min-height: 44px;
}

.feature-bullet-list {
  display: flex;
  flex-direction: column;
  gap: 10px;
  margin-bottom: 28px;
}

.feature-bullet-list li {
  font-size: 13px;
  color: #475569;
  display: flex;
  align-items: center;
  gap: 8px;
}

.feature-bullet-list li::before {
  content: '✓';
  color: var(--blue);
  font-weight: bold;
}

.card-actions {
  display: flex;
  gap: 16px;
}

.link-btn {
  font-size: 14px;
  font-weight: 600;
  color: var(--blue);
}

/* ==========================================================================
   核心防封黑科技板块样式
   ========================================================================== */
.tech-row-grid {
  display: flex;
  flex-direction: column;
  gap: 40px;
}

.tech-item-box {
  background: var(--surface-solid);
  border: 1px solid var(--line);
  border-radius: var(--radius-xl);
  padding: 40px;
  display: grid;
  grid-template-columns: 80px 1fr;
  gap: 30px;
  box-shadow: var(--shadow-md);
  align-items: flex-start;
}

.tech-badge-icon {
  width: 70px;
  height: 70px;
  border-radius: 16px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 32px;
}

.tech-badge-icon.shield-red { background: rgba(239, 68, 68, 0.08); color: #ef4444; }
.tech-badge-icon.route-cyan { background: rgba(6, 182, 212, 0.08); color: var(--cyan); }
.tech-badge-icon.brain-violet { background: rgba(124, 58, 237, 0.08); color: var(--violet); }

.tech-detail h3 {
  font-size: 20px;
  font-weight: 700;
  color: var(--text);
  margin-bottom: 12px;
}

.tech-detail p {
  font-size: 14px;
  line-height: 1.7;
  color: var(--muted);
}

/* ==========================================================================
   底层技术沉淀板块样式
   ========================================================================== */
.features-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}

.feature-card {
  background: var(--surface-solid);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  padding: 24px;
  text-align: center;
  box-shadow: var(--shadow-md);
}

.value-icon {
  font-size: 26px;
  color: var(--blue);
  margin-bottom: 14px;
}

.feature-card h3 {
  font-size: 16px;
  font-weight: 700;
  margin-bottom: 8px;
}

.feature-card p {
  font-size: 13px;
  color: var(--muted);
  line-height: 1.5;
}

/* ==========================================================================
   FAQ 折叠手风琴模块
   ========================================================================== */
.faq-accordion-box {
  max-width: 800px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.faq-row {
  background: var(--surface-solid);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  padding: 20px 24px;
}

.faq-q {
  font-size: 15px;
  font-weight: 700;
  color: var(--text);
  margin-bottom: 8px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.faq-q::before {
  content: 'Q:';
  color: var(--blue);
}

.faq-a {
  font-size: 13.5px;
  line-height: 1.6;
  color: var(--muted);
  padding-left: 22px;
}

.tg-float {
  position: fixed;
  right: 24px;
  bottom: 38px;
  z-index: 40;
  display: flex;
  align-items: flex-end;
  gap: 7px;
}

.tg-float__panel {
  width: 220px;
  padding: 14px;
  border-radius: 20px;
  border: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.98);
  box-shadow: 0 18px 42px rgba(15, 23, 42, 0.14);
  opacity: 0;
  transform: translateY(8px);
  pointer-events: none;
  transition: opacity 0.22s ease, transform 0.22s ease;
}

.tg-float:hover .tg-float__panel {
  opacity: 1;
  transform: translateY(0);
  pointer-events: auto;
}

.tg-float__qr {
  width: 100%;
  border-radius: 14px;
  display: block;
  margin-bottom: 10px;
}

.tg-float__desc {
  font-size: 12px;
  line-height: 1.7;
  color: var(--muted);
  text-align: center;
}

.tg-float__button {
  width: 64px;
  height: 64px;
  border-radius: 50%;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(135deg, #38bdf8, #2563eb);
  color: #ffffff;
  font-size: 28px;
  box-shadow: 0 18px 38px rgba(37, 99, 235, 0.30);
  transition: transform 0.22s ease, box-shadow 0.22s ease;
}

.tg-float__button:hover {
  color: #ffffff;
  transform: translateY(-4px) scale(1.04);
  box-shadow: 0 22px 44px rgba(37, 99, 235, 0.34);
}

/* ==========================================================================
   全局页脚样式
   ========================================================================== */
.site-footer {
  border-top: 1px solid var(--line);
  background: #ffffff;
  padding: 60px 0 30px;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr repeat(3, 1fr);
  gap: 40px;
  margin-bottom: 36px;
}

.brand-footer strong { color: var(--text); font-size: 18px; }
.footer-copy { color: var(--muted); font-size: 13px; margin-top: 12px; line-height: 1.6; }

.site-footer h3 {
  color: var(--text);
  font-size: 14px;
  font-weight: 700;
  margin-bottom: 16px;
}

.site-footer a {
  display: block;
  color: var(--muted);
  font-size: 13px;
  margin-bottom: 10px;
  transition: color 0.2s;
}

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

.footer-bottom {
  text-align: center;
  padding-top: 24px;
  border-top: 1px solid var(--line);
  color: #94a3b8;
  font-size: 12px;
}

/* ==========================================================================
   动画与响应式断点
   ========================================================================== */
@keyframes ssaasFloating {
  0% { transform: translateY(0px); }
  50% { transform: translateY(-6px); }
  100% { transform: translateY(0px); }
}

@media (max-width: 1024px) {
  .hero-grid, .systems-grid, .tech-item-box { grid-template-columns: 1fr; }
  .features-grid { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: 1fr repeat(3, 1fr); }
  .saas-browser-window { animation: none; margin-top: 20px; }
  .browser-content { height: auto; }
  .saas-dashboard-img { height: auto; object-fit: contain; }
  .browser-bottom-fade { display: none; }
}

@media (max-width: 640px) {
  .features-grid, .footer-grid { grid-template-columns: 1fr; }
  .hero-stats-strip { flex-direction: column; gap: 16px; }
  .tg-float {
    right: 14px;
    bottom: 14px;
  }

  .tg-float__panel {
    width: 180px;
  }

  .tg-float__button {
    width: 56px;
    height: 56px;
    font-size: 24px;
  }
}
/* ==========================================================================
   二级子页面互跳：导航栏全能下拉菜单样式
   ========================================================================== */

/* 让带有下拉菜单的导航项作为定位基准 */
.nav-item-dropdown {
  position: relative;
  display: inline-block;
}

/* 增加一个小箭头的微交互 */
.nav-link i.bi-chevron-down {
  font-size: 11px;
  margin-left: 4px;
  transition: transform 0.2s ease;
}

.nav-item-dropdown:hover .nav-link i.bi-chevron-down {
  transform: rotate(180deg); /* 鼠标悬停时箭头旋转 */
}

/* 下拉菜单面板主体 (明亮毛玻璃 SaaS 规范) */
.nav-dropdown-menu {
  position: absolute;
  top: 100%;
  left: 50%;
  transform: translateX(-50%) translateY(10px);
  width: 280px;
  background: rgba(255, 255, 255, 0.98);
  backdrop-filter: blur(16px);
  border: 1px solid #cbd5e1;
  border-radius: 12px;
  padding: 8px;
  box-shadow: 0 20px 40px rgba(15, 23, 42, 0.12);
  opacity: 0;
  visibility: hidden;
  transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
  z-index: 110;
}

/* 触发显示状态 */
.nav-item-dropdown:hover .nav-dropdown-menu {
  opacity: 1;
  visibility: visible;
  transform: translateX(-50%) translateY(4px);
}

/* 下拉独立功能小卡片 */
.dropdown-link-card {
  display: block;
  padding: 10px 14px;
  border-radius: 8px;
  transition: all 0.15s ease;
  margin-bottom: 2px;
}

.dropdown-link-card:last-child {
  margin-bottom: 0;
}

.dropdown-link-card strong {
  display: block;
  font-size: 13.5px;
  color: #0f172a;
  font-weight: 700;
  margin-bottom: 2px;
}

.dropdown-link-card span {
  display: block;
  font-size: 11.5px;
  color: #64748b;
  line-height: 1.4;
}

/* 三个系统的悬停专属高亮色反馈 */
.dropdown-link-card.hover-orange:hover { background: rgba(245, 158, 11, 0.06); }
.dropdown-link-card.hover-orange:hover strong { color: #d97706; }

.dropdown-link-card.hover-green:hover { background: rgba(16, 185, 129, 0.06); }
.dropdown-link-card.hover-green:hover strong { color: #059669; }

.dropdown-link-card.hover-blue:hover { background: rgba(37, 99, 235, 0.06); }
.dropdown-link-card.hover-blue:hover strong { color: var(--blue); }