/* ==== 1. 配色变量 ==== */
:root {
  --bg-gradient-start: #0ff5d6;
  --bg-gradient-mid:   #0794f1;
  --bg-gradient-end:   #08fad2;

  --card-background: rgba(255, 255, 255, 0.9);
  --card-border-radius: 14px;
  --card-box-shadow: rgba(0, 0, 0, 0.12);

  --text-title: #6d2a4a;
  --text-subtitle: #6d2a4a;

  --btn-bg: #0befff;
  --btn-bg-hover: #0d67ee;
  --btn-text-color: #180000;

  --announcement-bg: rgba(255, 126, 185, 0.15);
  --announcement-border: rgba(255, 255, 255, 0.4);
  --announcement-text: #6d2a4a;
}

/* ==== 2. 全局基础 ==== */
* { margin:0; padding:0; box-sizing:border-box; font-family:-apple-system,BlinkMacSystemFont,'PingFang SC','Segoe UI',sans-serif; }
body {
  background: linear-gradient(135deg,
    var(--bg-gradient-start),
    var(--bg-gradient-mid),
    var(--bg-gradient-end));
  min-height: 100vh;
  padding: 12px;
  display: flex;
  justify-content: center;
  align-items: flex-start;
}

.nav-container {
  width: 100%;
  max-width: 480px;
  background: var(--card-background);
  border-radius: var(--card-border-radius);
  box-shadow: 0 6px 16px var(--card-box-shadow);
  padding: 20px;
  text-align: center;
}

.nav-container h1 {
  font-size: 1.8rem;
  color: var(--text-title);
  margin-bottom: 8px;
  font-weight: 700;
}
.nav-container p.subtitle {
  font-size: 0.9rem;
  color: var(--text-subtitle);
  margin-bottom: 16px;
  line-height: 1.5;
}

.announcement {
  background: var(--announcement-bg);
  border: 1px solid var(--announcement-border);
  border-radius: 10px;
  padding: 10px 14px;
  margin-bottom: 20px;
  text-align: left;
}
.announcement p {
  color: var(--announcement-text);
  font-size: 0.85rem;
  line-height: 1.4;
  margin-bottom: 4px;
}

.btn-card {
  background: #fff;
  border-radius: 12px;
  box-shadow: 0 4px 12px var(--card-box-shadow);
  margin-bottom: 14px;
  padding: 12px;
  text-align: center;
}
.btn {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  width: 100%;
  padding: 12px 0;
  background: var(--btn-bg);
  color: var(--btn-text-color);
  font-size: 1rem;
  font-weight: 600;
  border-radius: 8px;
  text-decoration: none;
  transition: background 0.25s ease;
}
.btn:hover { background: var(--btn-bg-hover); }

.app-image {
  width: 100%;
  max-width: 280px;
  margin: 16px auto 0;
  display: block;
  border-radius: 12px;
  box-shadow: 0 6px 16px rgba(0,0,0,0.12);
}

.decoration {
  margin-top: 20px;
  height: 60px;
  background: url('data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 1440 320"><path fill="rgba(255,255,255,0.2)" d="M0,224L48,218.7C96,213,192,203,288,181.3C384,160,480,128,576,138.7C672,149,768,203,864,229.3C960,256,1056,256,1152,229.3C1248,203,1344,149,1392,122.7L1440,96L1440,320L0,320Z"></path></svg>') no-repeat bottom;
  background-size: cover;
}