body {
  font-family: Roboto, system-ui, sans-serif;
  background: var(--bg);
  color: var(--text);
}

.top-bar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 16px 24px;
}

.top-bar nav a {
  margin: 0 12px;
  cursor: pointer;
}

.hero {
  text-align: center;
  padding: 120px 16px;
}

.hero h1 {
  font-size: 44px;
  margin-bottom: 12px;
}

.hero p {
  opacity: 0.7;
  font-size: 18px;
}

.cta {
  display: inline-block;
  margin-top: 32px;
  padding: 14px 32px;
  background: var(--primary);
  color: #fff;
  border-radius: 999px;
  text-decoration: none;
}

.platforms {
  display: flex;
  justify-content: center;
  gap: 16px;
  padding: 40px;
}

.chip {
  background: var(--card);
  padding: 10px 18px;
  border-radius: 999px;
}

.features {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 24px;
  padding: 40px;
}

.card {
  background: var(--card);
  padding: 32px;
  border-radius: var(--radius);
  text-align: center;
  font-size: 18px;
}

footer {
  text-align: center;
  padding: 24px;
  font-size: 12px;
  opacity: 0.6;
}

.screenshots {
  padding: 64px 16px;
  text-align: center;
}

.screenshots h2 {
  font-size: 28px;
  margin-bottom: 24px;
}

.carousel {
  position: relative;
  max-width: 960px;
  margin: 0 auto;
  overflow: hidden;
  border-radius: 24px;
  background: var(--card);
}

.carousel-track {
  display: flex;
  transition: transform 0.45s cubic-bezier(.4, 0, .2, 1);
}

.carousel-track img {
  width: 100%;
  flex-shrink: 0;
  object-fit: contain;
  background: #000;
}

/* 左右按钮（Material 悬浮感） */
.carousel .nav {
  position: absolute;
  top: 50%;
  transform: translateY(-50%);
  width: 44px;
  height: 44px;
  border-radius: 50%;
  border: none;
  background: rgba(0, 0, 0, .45);
  color: #fff;
  font-size: 28px;
  cursor: pointer;
}

.carousel .prev {
  left: 12px;
}

.carousel .next {
  right: 12px;
}

.carousel .nav:hover {
  background: rgba(0, 0, 0, .65);
}

.device-carousel {
  position: relative;
  max-width: 960px;
  margin: 0 auto;
  overflow: hidden;
}

.device-track {
  display: flex;
  transition: transform .5s cubic-bezier(.4, 0, .2, 1);
}

.device {
  flex: 0 0 100%;
  display: flex;
  justify-content: center;
}

.device .screen {
  background: #000;
  overflow: hidden;
}

.device.phone .screen {
  width: 280px;
  height: 580px;
  border-radius: 36px;
  padding: 12px;
  background: #000;
  box-shadow:
    0 20px 40px rgba(0, 0, 0, .25),
    inset 0 0 0 6px #222;
}

.device.phone img {
  width: 100%;
  height: 100%;
  border-radius: 24px;
  object-fit: cover;
}

.device.tablet .screen {
  width: 520px;
  height: 360px;
  border-radius: 28px;
  padding: 12px;
  box-shadow: 0 20px 40px rgba(0, 0, 0, .2);
}

.device.tablet img {
  width: 100%;
  height: 100%;
  border-radius: 18px;
  object-fit: cover;
}

.device.tv .screen {
  width: 640px;
  height: 360px;
  border-radius: 12px;
  padding: 10px;
  box-shadow: 0 24px 48px rgba(0, 0, 0, .3);
}

.device.tv img {
  width: 100%;
  height: 100%;
  border-radius: 6px;
  object-fit: contain;
  background: #000;
}

html[data-theme="dark"] .device .screen {
  box-shadow:
    0 20px 40px rgba(0, 0, 0, .6),
    inset 0 0 0 6px #111;
}

.inner-carousel {
  width: 100%;
  height: 100%;
  position: relative;
  overflow: hidden;
}

.inner-track {
  display: flex;
  height: 100%;
  transition: transform .45s cubic-bezier(.4, 0, .2, 1);
}

.inner-track img {
  width: 100%;
  height: 100%;
  flex-shrink: 0;
  object-fit: cover;
}

.inner-dots {
  position: absolute;
  bottom: 10px;
  left: 0;
  right: 0;
  display: flex;
  justify-content: center;
  gap: 6px;
}

.inner-dots span {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: rgba(255, 255, 255, .4);
}

.inner-dots span.active {
  background: #fff;
  width: 18px;
  border-radius: 999px;
}

.device-tabs {
  position: relative;
  display: flex;
  gap: 24px;
  justify-content: center;
  margin-bottom: 32px;
}

.device-tabs .tab {
  background: none;
  border: none;
  font-size: 16px;
  padding: 8px 4px;
  cursor: pointer;
  color: var(--text);
  opacity: .6;
}

.device-tabs .tab.active {
  opacity: 1;
  font-weight: 500;
}

.tab-indicator {
  position: absolute;
  left: 0;
  bottom: -6px;
  height: 3px;
  width: 24px;
  background: var(--primary);
  border-radius: 999px;
  transition: transform .35s cubic-bezier(.4,0,.2,1);
}