:root {
  --bg: #f7f8fc;
  --card: #ffffff;
  --text: #1f2a44;
  --muted: #8d96a8;
  --brand: #3b66db;
  --brand-press: #2d55c4;
  --line: #dce4f4;
}

* {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Segoe UI", sans-serif;
}

.page {
  position: relative;
  min-height: 100dvh;
  max-width: 780px;
  margin: 0 auto;
  padding: calc(env(safe-area-inset-top) + 18px) 18px calc(env(safe-area-inset-bottom) + 98px);
  overflow: hidden;
}

.bg-shape {
  position: absolute;
  border-radius: 50%;
  filter: blur(2px);
  pointer-events: none;
}

.bg-shape-top {
  width: 460px;
  height: 460px;
  right: -190px;
  top: -210px;
  background: radial-gradient(circle at 45% 45%, #edf3ff 0%, #e9f0ff 45%, #f7f8fc 75%);
}

.bg-shape-middle {
  width: 560px;
  height: 560px;
  left: -280px;
  top: 270px;
  background: radial-gradient(circle at 30% 40%, #f3f6ff 0%, #f6f8ff 48%, #f7f8fc 76%);
}

.brand {
  position: relative;
  z-index: 2;
  text-align: center;
  padding-top: 14px;
}

.brand-logo {
  width: 56px;
  height: 56px;
  border-radius: 14px;
  box-shadow: 0 8px 20px rgba(59, 102, 219, 0.16);
}

.brand-title {
  margin: 12px 0 8px;
  font-size: clamp(42px, 9.4vw, 56px);
  font-weight: 700;
  letter-spacing: 0.02em;
  color: #3f6ee6;
}

.brand-subtitle {
  margin: 0;
  color: #8a93a6;
  font-size: 15px;
  font-weight: 600;
}

.brand-note {
  margin: 8px 0 0;
  color: #7a8397;
  font-size: 14px;
  font-weight: 500;
}

.hero {
  position: relative;
  z-index: 1;
  display: flex;
  justify-content: center;
  margin-top: 14px;
  min-height: min(58vh, 780px);
}

.phone-wrap {
  width: min(88vw, 370px);
}

.phone-image {
  display: block;
  width: 100%;
  height: auto;
  filter: drop-shadow(0 18px 36px rgba(41, 65, 124, 0.13));
}

.download {
  position: fixed;
  left: 50%;
  bottom: calc(env(safe-area-inset-bottom) + 12px);
  transform: translateX(-50%);
  width: min(90vw, 680px);
  z-index: 20;
}

.download-btn {
  width: 100%;
  min-height: 58px;
  border: 0;
  border-radius: 999px;
  background: var(--brand);
  color: #fff;
  font-size: 24px;
  font-weight: 700;
  letter-spacing: 0.02em;
  cursor: pointer;
  box-shadow: 0 14px 24px rgba(61, 94, 199, 0.3);
  transition: transform 160ms ease, box-shadow 160ms ease, background-color 160ms ease;
}

.download-btn:active {
  transform: translateY(1px) scale(0.997);
  background: var(--brand-press);
}

.download-btn:focus-visible {
  outline: 3px solid #9db8ff;
  outline-offset: 2px;
}

@media (max-width: 420px) {
  .brand-title {
    font-size: 40px;
  }

  .brand-subtitle,
  .brand-note {
    font-size: 12px;
  }

  .download-btn {
    font-size: 19px;
    min-height: 50px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .download-btn {
    transition: none;
  }
}