/* ==========================================================================
   驱动精灵官网 - 「桥面伸缩缝」空间隐喻 轻量纯净最终版 样式表
   核心概念：页面几乎是一片桥面混凝土，一条伸缩缝斜着切开，缝里能看到下面。
   骨架：混凝土、斜缝、缝下。
   色彩：混凝土 (#545961 / #747983 / #e8ebf0)、缝影 (#16181c / #20242b)、缝下河水 (#00796b / #26a69a / #80cbc4)
   ========================================================================== */

:root {
  --concrete-base: #525760;
  --concrete-light: #707580;
  --concrete-bg: #ebeeef;
  --concrete-card: #f8fafc;
  --concrete-border: rgba(90, 98, 108, 0.2);

  --gap-shadow-deep: #14161a;
  --gap-steel-edge: #343942;
  --gap-steel-comb: #484f5c;

  --river-under-deep: #004d40;
  --river-under: #00796b;
  --river-under-glow: #26a69a;
  --river-under-foam: #80cbc4;

  --brand-blue: #1e5eff;
  --brand-blue-hover: #0d47a1;
  --brand-teal: #00897b;
  --brand-gradient: linear-gradient(135deg, #1e5eff 0%, #00897b 100%);
  --ribbon-gradient: linear-gradient(135deg, #e8f0fe 0%, #e0f2f1 100%);

  --bg-page: #f4f6f8;
  --bg-card: #ffffff;
  --text-heading: #1a202c;
  --text-body: #4a5568;
  --text-light: #718096;
  --border-subtle: #e2e8f0;
  --border-card: #edf2f7;

  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --radius-pill: 9999px;

  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.04);
  --shadow-md: 0 8px 24px rgba(0, 0, 0, 0.07);
  --shadow-hover: 0 16px 36px rgba(0, 0, 0, 0.12);
  --shadow-concrete: 0 20px 48px rgba(28, 32, 38, 0.35);
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  color: var(--text-body);
  background-color: var(--bg-page);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

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

/* ==========================================================================
   1. 顶栏 (Header)
   左 logo，右五个文字链，同一行两端对齐
   ========================================================================== */
.site-header {
  background: rgba(255, 255, 255, 0.96);
border-bottom: 1px solid var(--border-subtle);
  position: sticky;
  top: 0;
  z-index: 1000;
  transition: all 0.25s ease;
}

.nav-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
}

.brand-logo {
  display: flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
}

.brand-logo-img {
  height: 40px;
  width: auto;
  object-fit: contain;
}

.brand-badge {
  font-size: 11px;
  background: rgba(0, 137, 123, 0.1);
  color: var(--brand-teal);
  padding: 3px 10px;
  border-radius: var(--radius-pill);
  font-weight: 700;
  letter-spacing: 0.5px;
  border: 1px solid rgba(0, 137, 123, 0.25);
}

.nav-links {
  display: flex;
  align-items: center;
  list-style: none;
  gap: 36px;
}

.nav-link {
  color: var(--text-body);
  text-decoration: none;
  font-size: 15px;
  font-weight: 500;
  transition: color 0.2s ease;
  position: relative;
  padding: 8px 0;
}

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

.nav-link.active::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 2px;
  background: var(--brand-teal);
  border-radius: 2px;
}

.nav-btn-highlight {
  background: var(--brand-teal);
  color: #ffffff !important;
  padding: 8px 20px !important;
  border-radius: var(--radius-pill);
  transition: all 0.2s ease;
  box-shadow: 0 4px 12px rgba(0, 137, 123, 0.25);
}

.nav-btn-highlight:hover {
  background: #00695c !important;
  transform: translateY(-1px);
}

/* ==========================================================================
   2. 主视觉 (Hero Section) - 「桥面伸缩缝」
   通栏大圆角卡片，标题和说明靠左，说明只占卡片宽度的 70%，口号
   骨架：混凝土、斜缝、缝下
   颜色：混凝土、缝影和一点下面的河
   缝上写“驱动精灵官网”，桥面写“驱动精灵”，缝左写“驱动精灵下载”，缝下写“驱动精灵绿色版”
   ========================================================================== */
.hero-wrapper {
  padding: 36px 0 20px;
}

.hero-large-card {
  background: linear-gradient(150deg, #424750 0%, #565c66 50%, #3a3f47 100%);
  border-radius: var(--radius-lg);
  padding: 48px 48px 40px;
  box-shadow: var(--shadow-concrete);
  border: 1px solid rgba(144, 153, 166, 0.3);
  position: relative;
  overflow: hidden;
  color: #ffffff;
}

.hero-title-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: rgba(38, 166, 154, 0.2);
  border: 1px solid rgba(128, 203, 196, 0.45);
  color: #e0f2f1;
  font-size: 13px;
  font-weight: 600;
  padding: 6px 16px;
  border-radius: var(--radius-pill);
  margin-bottom: 20px;
}

.hero-main-heading {
  font-size: 38px;
  line-height: 1.25;
  font-weight: 800;
  letter-spacing: -0.5px;
  color: #ffffff;
  margin-bottom: 18px;
}

.gradient-text {
  background: linear-gradient(135deg, #80cbc4 0%, #4dd0e1 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

/* 说明只占卡片宽度的 70% 靠左 */
.hero-desc-70 {
  width: 70%;
  max-width: 70%;
  font-size: 16px;
  line-height: 1.8;
  color: rgba(255, 255, 255, 0.88);
  margin-bottom: 24px;
}

.hero-slogan-box {
  background: rgba(255, 255, 255, 0.08);
  border-left: 4px solid var(--river-under-glow);
  padding: 12px 20px;
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  margin-bottom: 32px;
  font-size: 15px;
  color: #e0f2f1;
}

.hero-slogan-box strong {
  color: #b2dfdb;
}

/* 「桥面伸缩缝」具象空间舞台 */
.bridge-gap-scene {
  position: relative;
  background: #2b3038;
  border-radius: var(--radius-md);
  padding: 34px 28px;
  border: 1px solid rgba(144, 153, 166, 0.35);
  margin-top: 10px;
  overflow: hidden;
  box-shadow: inset 0 2px 20px rgba(0, 0, 0, 0.6);
}

/* 桥面大面积混凝土：桥面写“驱动精灵” */
.concrete-deck-surface {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 24px;
  position: relative;
  z-index: 2;
}

.concrete-deck-tag {
  background: linear-gradient(90deg, #494e58, #606672);
  border: 2px solid #8c93a0;
  color: #ffffff;
  font-size: 16px;
  font-weight: 800;
  padding: 8px 24px;
  border-radius: 6px;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.3);
  display: inline-flex;
  align-items: center;
  gap: 10px;
}

.concrete-deck-tag::before {
  content: "🌉";
}

.concrete-desc-pill {
  font-size: 12px;
  color: #c4cbd4;
  background: rgba(0, 0, 0, 0.3);
  padding: 4px 12px;
  border-radius: var(--radius-pill);
}

/* 伸缩缝斜向切开构造 */
.expansion-gap-oblique-track {
  position: relative;
  padding: 36px 20px;
  margin: 10px 0;
  /* 斜向切割纵深渐变 */
  background: linear-gradient(115deg, #23272e 0%, #17191e 35%, #004d40 50%, #17191e 65%, #23272e 100%);
  border-radius: var(--radius-md);
  border-top: 3px dashed #6b7280;
  border-bottom: 3px dashed #6b7280;
  box-shadow: inset 0 0 30px rgba(0, 0, 0, 0.8), 0 0 16px rgba(0, 121, 107, 0.3);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
}

/* 缝上写“驱动精灵官网” */
.gap-above-official {
  background: linear-gradient(135deg, #263238, #37474f);
  border: 2px solid #64b5f6;
  border-radius: var(--radius-md);
  padding: 12px 24px;
  color: #ffffff;
  text-decoration: none;
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.4);
  transition: transform 0.2s ease;
}

.gap-above-official:hover {
  transform: translateY(-2px);
  border-color: #90caf9;
}

.gap-above-official .gap-title {
  display: block;
  font-size: 17px;
  font-weight: 800;
  color: #e3f2fd;
}

.gap-above-official .gap-sub {
  font-size: 11px;
  color: #90caf9;
}

/* 缝左写“驱动精灵下载” */
.gap-left-download {
  background: linear-gradient(135deg, #bf360c, #e65100);
  border: 2px solid #ffb74d;
  color: #ffffff;
  padding: 12px 24px;
  border-radius: var(--radius-pill);
  text-decoration: none;
  font-weight: 700;
  font-size: 14px;
  box-shadow: 0 4px 16px rgba(230, 81, 0, 0.4);
  transition: all 0.2s ease;
}

.gap-left-download:hover {
  background: #f57c00;
  transform: translateY(-2px);
}

/* 缝下写“驱动精灵绿色版”（从缝隙透视看到下面的碧水波光） */
.gap-under-river {
  background: linear-gradient(135deg, #004d40, #00796b);
  border: 2px solid var(--river-under-glow);
  color: #ffffff;
  padding: 12px 26px;
  border-radius: var(--radius-md);
  text-decoration: none;
  box-shadow: 0 0 20px rgba(38, 166, 154, 0.45);
  transition: all 0.2s ease;
  text-align: right;
}

.gap-under-river:hover {
  transform: translateY(-2px);
  box-shadow: 0 0 28px rgba(38, 166, 154, 0.6);
}

.gap-under-river .river-title {
  display: block;
  font-size: 17px;
  font-weight: 800;
  color: #e0f2f1;
}

.gap-under-river .river-sub {
  font-size: 11px;
  color: #80cbc4;
}

/* ==========================================================================
   3. 下载 (Download CTA Section)
   整行居中的一颗胶囊按钮，下面一行灰色系统说明 (唯一主行动)
   ========================================================================== */
.download-action-section {
  padding: 36px 0 44px;
  text-align: center;
}

.capsule-btn-wrapper {
  display: flex;
  justify-content: center;
  align-items: center;
  margin-bottom: 12px;
}

.capsule-btn {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  background: var(--brand-gradient);
  color: #ffffff;
  padding: 18px 48px;
  border-radius: var(--radius-pill);
  font-size: 18px;
  font-weight: 700;
  text-decoration: none;
  box-shadow: 0 8px 28px rgba(0, 137, 123, 0.35);
  transition: all 0.25s ease;
  border: 1px solid rgba(255, 255, 255, 0.2);
}

.capsule-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 12px 36px rgba(0, 137, 123, 0.45);
}

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

.capsule-btn:hover svg {
  transform: translateY(2px);
}

.system-gray-spec {
  color: var(--text-light);
  font-size: 14px;
  line-height: 1.6;
}

/* ==========================================================================
   4. 数据 (Stats Section)
   四列等宽白卡片：用户、日活、下载、国家
   ========================================================================== */
.stats-section {
  padding: 10px 0 44px;
}

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

.stat-card-white {
  background: var(--bg-card);
  border-radius: var(--radius-md);
  padding: 28px 24px;
  border: 1px solid var(--border-card);
  box-shadow: var(--shadow-sm);
  text-align: center;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.stat-card-white:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
}

.stat-number {
  font-size: 34px;
  font-weight: 800;
  color: var(--brand-teal);
  line-height: 1.2;
  margin-bottom: 6px;
}

.stat-label {
  font-size: 15px;
  font-weight: 600;
  color: var(--text-heading);
  margin-bottom: 4px;
}

.stat-subtext {
  font-size: 13px;
  color: var(--text-light);
}

/* ==========================================================================
   5. 介绍 (Intro Ribbon Section)
   一条浅蓝到浅紫的通栏色带，标题加一段长文 (品牌说明)
   ========================================================================== */
.intro-ribbon-section {
  padding: 10px 0 54px;
}

.intro-ribbon-card {
  background: var(--ribbon-gradient);
  border-radius: var(--radius-lg);
  padding: 44px 48px;
  border: 1px solid rgba(0, 137, 123, 0.15);
  box-shadow: var(--shadow-sm);
}

.intro-ribbon-content {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 36px;
  align-items: center;
}

.intro-heading {
  font-size: 28px;
  font-weight: 800;
  color: var(--text-heading);
  line-height: 1.35;
  margin-bottom: 18px;
}

.intro-long-text {
  font-size: 15px;
  line-height: 1.85;
  color: #334155;
}

.intro-long-text p + p {
  margin-top: 14px;
}

.intro-media-box {
  border-radius: var(--radius-md);
  overflow: hidden;
  box-shadow: var(--shadow-md);
  border: 1px solid rgba(255, 255, 255, 0.8);
}

/* ==========================================================================
   6. 功能 (Core Features Section)
   左对齐标题，下面三列共六张卡
   ========================================================================== */
.features-section {
  padding: 20px 0 60px;
}

.section-title-left {
  font-size: 28px;
  font-weight: 800;
  color: var(--text-heading);
  text-align: left;
  margin-bottom: 8px;
}

.section-subtitle-left {
  font-size: 15px;
  color: var(--text-light);
  text-align: left;
  margin-bottom: 32px;
}

.features-grid-3x2 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.feature-item-card {
  background: var(--bg-card);
  border-radius: var(--radius-md);
  padding: 28px 24px;
  border: 1px solid var(--border-card);
  box-shadow: var(--shadow-sm);
  transition: all 0.25s ease;
}

.feature-item-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
  border-color: rgba(0, 137, 123, 0.3);
}

.feature-icon-circle {
  width: 48px;
  height: 48px;
  border-radius: 12px;
  background: rgba(0, 137, 123, 0.08);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 22px;
  color: var(--brand-teal);
  margin-bottom: 18px;
}

.feature-title {
  font-size: 18px;
  font-weight: 700;
  color: var(--text-heading);
  margin-bottom: 10px;
}

.feature-desc {
  font-size: 14px;
  line-height: 1.7;
  color: var(--text-body);
}

/* ==========================================================================
   7. 分类 (Categories Section)
   四列居中卡片，每张一个线性图标 (显卡、网卡、声卡、主板)
   ========================================================================== */
.categories-section {
  padding: 20px 0 60px;
}

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

.cat-center-card {
  background: var(--bg-card);
  border-radius: var(--radius-md);
  padding: 32px 20px;
  border: 1px solid var(--border-card);
  box-shadow: var(--shadow-sm);
  text-align: center;
  transition: all 0.25s ease;
}

.cat-center-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
  border-color: rgba(0, 137, 123, 0.3);
}

.cat-linear-icon {
  width: 60px;
  height: 60px;
  margin: 0 auto 18px;
  border-radius: 50%;
  background: #e0f2f1;
  color: var(--brand-teal);
  display: flex;
  align-items: center;
  justify-content: center;
}

.cat-title {
  font-size: 17px;
  font-weight: 700;
  color: var(--text-heading);
  margin-bottom: 8px;
}

.cat-desc {
  font-size: 13px;
  line-height: 1.6;
  color: var(--text-light);
}

/* ==========================================================================
   8. 问答 (FAQ Section)
   五张通栏白卡片，问题和答案全部摊开 (安装、备份、失败、离线、系统)
   ========================================================================== */
.faq-section {
  padding: 20px 0 60px;
}

.faq-stack-5 {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.faq-full-white-card {
  background: var(--bg-card);
  border-radius: var(--radius-md);
  padding: 28px 32px;
  border: 1px solid var(--border-card);
  box-shadow: var(--shadow-sm);
  transition: border-color 0.2s ease;
}

.faq-full-white-card:hover {
  border-color: rgba(0, 137, 123, 0.35);
}

.faq-question {
  display: flex;
  align-items: center;
  gap: 14px;
  font-size: 17px;
  font-weight: 700;
  color: var(--text-heading);
  margin-bottom: 12px;
}

.faq-q-tag {
  background: rgba(0, 137, 123, 0.1);
  color: var(--brand-teal);
  font-size: 12px;
  font-weight: 700;
  padding: 4px 10px;
  border-radius: 4px;
  flex-shrink: 0;
}

.faq-answer {
  font-size: 14px;
  line-height: 1.8;
  color: var(--text-body);
  padding-left: 54px;
}

/* ==========================================================================
   9. 指南 (Guides Section)
   一行四张等分小卡 (新手、备份、设置、离线)
   ========================================================================== */
.guides-section {
  padding: 20px 0 70px;
}

.guides-grid-4 {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}

.guide-step-card {
  background: var(--bg-card);
  border-radius: var(--radius-md);
  padding: 26px 22px;
  border: 1px solid var(--border-card);
  box-shadow: var(--shadow-sm);
  position: relative;
  transition: all 0.25s ease;
}

.guide-step-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
  border-color: rgba(0, 137, 123, 0.3);
}

.guide-step-num {
  font-size: 26px;
  font-weight: 900;
  color: #cfd8dc;
  line-height: 1;
  margin-bottom: 14px;
  display: block;
}

.guide-step-title {
  font-size: 16px;
  font-weight: 700;
  color: var(--text-heading);
  margin-bottom: 8px;
}

.guide-step-desc {
  font-size: 13px;
  line-height: 1.6;
  color: var(--text-light);
}

/* ==========================================================================
   10. 页脚 (Footer)
   四列：一段介绍加三组列表，上下各一条细线，版权居中
   ========================================================================== */
.site-footer {
  background: #ffffff;
  border-top: 1px solid var(--border-subtle);
  padding: 50px 0 36px;
  margin-top: 20px;
}

.footer-top-line {
  height: 1px;
  background: var(--border-subtle);
  margin-bottom: 40px;
}

.footer-grid-4 {
  display: grid;
  grid-template-columns: 1.5fr 1fr 1fr 1fr;
  gap: 40px;
  margin-bottom: 40px;
}

.footer-col-intro .footer-brand {
  font-size: 18px;
  font-weight: 800;
  color: var(--text-heading);
  margin-bottom: 14px;
}

.footer-intro-text {
  font-size: 13px;
  line-height: 1.8;
  color: var(--text-light);
}

.footer-heading {
  font-size: 15px;
  font-weight: 700;
  color: var(--text-heading);
  margin-bottom: 16px;
}

.footer-links {
  list-style: none;
}

.footer-link-item {
  margin-bottom: 10px;
}

.footer-link-item a {
  color: var(--text-light);
  font-size: 13px;
  text-decoration: none;
  transition: color 0.2s ease;
}

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

.footer-bottom-line {
  height: 1px;
  background: var(--border-subtle);
  margin-bottom: 24px;
}

.footer-copyright {
  text-align: center;
  font-size: 12px;
  color: var(--text-light);
}

/* ==========================================================================
   响应式媒体查询
   ========================================================================== */
@media (max-width: 1024px) {
  .hero-desc-70 {
    width: 85%;
    max-width: 85%;
  }
  .features-grid-3x2 {
    grid-template-columns: repeat(2, 1fr);
  }
  .stats-grid-4,
  .categories-grid-4,
  .guides-grid-4 {
    grid-template-columns: repeat(2, 1fr);
  }
  .intro-ribbon-content {
    grid-template-columns: 1fr;
  }
  .footer-grid-4 {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 768px) {
  .nav-links {
    display: none;
  }
  .hero-main-heading {
    font-size: 28px;
  }
  .hero-desc-70 {
    width: 100%;
    max-width: 100%;
  }
  .expansion-gap-oblique-track {
    flex-direction: column;
    align-items: stretch;
    text-align: center;
  }
  .gap-under-river {
    text-align: center;
  }
  .stats-grid-4,
  .categories-grid-4,
  .guides-grid-4,
  .features-grid-3x2 {
    grid-template-columns: 1fr;
  }
  .faq-answer {
    padding-left: 0;
  }
  .footer-grid-4 {
    grid-template-columns: 1fr;
  }
}


.features-section,
.faq-section,
.guides-section,
.categories-section,
.intro-band-section,
.site-footer {
  content-visibility: auto;
  contain-intrinsic-size: auto 520px;
}