/* 主色系：安全、防诈 #2F6BFF #F6F8FC #1F2D3D #5F6B7A */
:root {
  --primary: #2F6BFF;
  --primary-dark: #1d5ae8;
  --background: #F6F8FC;
  --background-deep: #e8eef8;
  --text-primary: #1F2D3D;
  --text-secondary: #5F6B7A;
  --white: #ffffff;
}

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

html {
  font-size: 18px;
  -webkit-font-smoothing: antialiased;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
  color: #e4e8f0;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 32px 0 48px;
  position: relative;
  overflow-x: hidden;
}

/* 炫酷科技感背景：深色渐变 + 光效 + 可选背景图（无版权） */
.body-bg {
  position: fixed;
  inset: 0;
  z-index: -1;
  background: linear-gradient(165deg, #0c1222 0%, #1a1f3a 25%, #16213e 50%, #0f3460 75%, #1a1f3a 100%);
}

.body-bg .bg-image {
  position: absolute;
  inset: 0;
  background-size: cover;
  background-position: center;
  background-repeat: no-repeat;
  opacity: 0.35;
  pointer-events: none;
}

.body-bg::before {
  content: '';
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(47, 107, 255, 0.07) 1px, transparent 1px),
    linear-gradient(90deg, rgba(47, 107, 255, 0.07) 1px, transparent 1px);
  background-size: 48px 48px;
  pointer-events: none;
}

.body-bg::after {
  content: '';
  position: absolute;
  inset: 0;
  background:
    radial-gradient(ellipse 120% 80% at 20% 0%, rgba(47, 107, 255, 0.25) 0%, transparent 50%),
    radial-gradient(ellipse 80% 60% at 80% 100%, rgba(99, 102, 241, 0.2) 0%, transparent 50%),
    radial-gradient(ellipse 60% 40% at 50% 50%, rgba(79, 172, 254, 0.08) 0%, transparent 60%);
  pointer-events: none;
}

/* 主内容区：按红框宽度布局，不限制在中间一小块 */
.container {
  max-width: 1100px;
  width: 100%;
  text-align: center;
  padding: 0 40px;
}

.logo {
  width: 140px;
  height: 140px;
  margin: 0 auto 24px;
  display: block;
  border-radius: 28px;
  object-fit: contain;
  box-shadow: 0 12px 32px rgba(47, 107, 255, 0.2);
}

h1 {
  font-size: 2.75rem;
  font-weight: 700;
  color: #fff;
  margin-bottom: 12px;
  letter-spacing: 0.02em;
  line-height: 1.2;
  text-shadow: 0 2px 8px rgba(0, 0, 0, 0.3);
}

.subtitle {
  font-size: 1.5rem;
  color: #93b8ff;
  font-weight: 600;
  margin-bottom: 20px;
  letter-spacing: 0.03em;
}

.intro {
  font-size: 1.2rem;
  color: rgba(228, 232, 240, 0.9);
  line-height: 1.65;
  margin-bottom: 24px;
}

.description {
  text-align: left;
  font-size: 1.1rem;
  color: rgba(228, 232, 240, 0.95);
  line-height: 1.75;
  margin-bottom: 40px;
  padding: 0 24px;
  max-width: 100%;
}

.description p {
  margin-bottom: 14px;
}

.description p:last-child {
  margin-bottom: 0;
}

.description strong {
  color: #93b8ff;
}

.download-wrap {
  margin-top: 36px;
  display: flex;
  flex-wrap: wrap;
  gap: 18px;
  justify-content: center;
  align-items: center;
}

.btn-download {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
  min-width: 200px;
  padding: 18px 32px;
  font-size: 1.15rem;
  font-weight: 600;
  color: #fff;
  background: var(--primary);
  border: none;
  border-radius: 16px;
  cursor: pointer;
  text-decoration: none;
  transition: background 0.2s, transform 0.05s;
  box-shadow: 0 6px 20px rgba(47, 107, 255, 0.35);
}

.btn-download:hover {
  background: var(--primary-dark);
}

.btn-download:active {
  transform: scale(0.98);
}

.btn-download svg {
  width: 26px;
  height: 26px;
  flex-shrink: 0;
}

.btn-download.btn-google {
  background: #1a1a1a;
  box-shadow: 0 6px 20px rgba(0, 0, 0, 0.2);
}

.btn-download.btn-google:hover {
  background: #333;
}

/* 下方：四张图固定 9:16，整页横向一排、宽度不限制不换行 */
.carousel-section {
  width: 100%;
  margin-top: 56px;
  padding: 0 32px 32px;
  box-sizing: border-box;
}

.carousel-section h2 {
  font-size: 1.4rem;
  color: #fff;
  margin-bottom: 24px;
  text-align: center;
  font-weight: 700;
  padding: 0 16px;
}

.carousel-track {
  display: flex;
  flex-wrap: nowrap;
  justify-content: space-evenly;
  align-items: flex-start;
  gap: 28px;
  width: 100%;
  min-width: 0;
  padding: 0 16px;
}

@media (max-width: 1240px) {
  .carousel-track {
    flex-wrap: wrap;
    justify-content: center;
  }
}

.carousel-slide {
  flex: 0 0 auto;
  width: 280px;
  min-width: 0;
}

.carousel-image-wrap {
  aspect-ratio: 9 / 16;
  width: 100%;
  border-radius: 16px;
  overflow: hidden;
  background: linear-gradient(145deg, #1e2a4a 0%, #2a3560 100%);
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.35);
}

.carousel-image-wrap img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

.carousel-caption {
  margin-top: 14px;
  padding: 0 4px;
  text-align: center;
}

.carousel-caption .slide-title {
  font-size: 1.05rem;
  font-weight: 600;
  color: #fff;
  margin-bottom: 4px;
}

.carousel-caption .slide-desc {
  font-size: 0.95rem;
  color: rgba(228, 232, 240, 0.8);
  line-height: 1.5;
}

.toast {
  position: fixed;
  bottom: 32px;
  left: 50%;
  transform: translateX(-50%) translateY(80px);
  padding: 16px 28px;
  background: var(--text-primary);
  color: #fff;
  font-size: 1rem;
  border-radius: 12px;
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.2);
  opacity: 0;
  transition: transform 0.3s, opacity 0.3s;
  z-index: 1000;
  pointer-events: none;
}

.toast.show {
  transform: translateX(-50%) translateY(0);
  opacity: 1;
}

/* 页脚：固定在页面最底部 */
.page-footer {
  margin-top: auto;
  padding: 28px 24px 32px;
  border-top: 1px solid rgba(255, 255, 255, 0.12);
  font-size: 0.95rem;
  color: rgba(228, 232, 240, 0.75);
  text-align: center;
  line-height: 1.9;
  width: 100%;
  box-sizing: border-box;
}

.page-footer a {
  color: #93b8ff;
  text-decoration: none;
}

.page-footer a:hover {
  text-decoration: underline;
}

.page-footer .footer-links {
  margin-bottom: 8px;
}

.page-footer .footer-links span {
  margin: 0 10px;
  color: rgba(255, 255, 255, 0.3);
}

.page-footer .copyright {
  margin-top: 6px;
}

.page-footer .contact {
  margin-top: 6px;
}