* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  background: #0b0f19;
  color: #e5e7eb;
}

a { color: #7dd3fc; text-decoration: none; }

.hero {
 padding: 64px 24px;
  background: linear-gradient(135deg, #2563eb, #06b6d4);
  display: flex;          /* 启用 flexbox */
  flex-direction: column; /* 垂直排列 */
  align-items: center;    /* 水平居中所有元素 */
  text-align: center;     /* 文本居中 */
}
/* 大标题 */
.hero h1 {
    font-size: 3rem;       /* 可根据需求调整大小 */
    font-weight: 700;
    margin: 0;
}
/* 副标题 */
.hero p.hero-sub {
    font-size: 1.2rem;
    opacity: 0.85;
    margin-top: 12px;
}
.top-bar {
  display: flex;
  justify-content: space-between;
  align-items: center;
}
/* 按钮 */
.hero-actions {
    margin-top: 24px;
}
.hero-actions .btn {
    margin-right: 12px;
}
.lang-switch button {
  background: rgba(255,255,255,.15);
  border: none;
  color: #fff;
  margin-left: 8px;
  padding: 6px 12px;
  border-radius: 6px;
  cursor: pointer;
}

.hero-sub {
  margin: 24px 0;
  font-size: 20px;
    opacity: 0.85;
    margin-top: 12px;
}

.hero-actions .btn {
  margin-right: 12px;
}

.btn {
  padding: 12px 22px;
  border-radius: 8px;
  font-weight: 600;
}

.primary {
  background: #fff;
  color: #2563eb;
}

.ghost {
  border: 1px solid rgba(255,255,255,.5);
  color: #fff;
}

.container {
  max-width: 1100px;
  margin: auto;
  padding: 48px 24px;
}

.card {
  background: #111827;
  border-radius: 12px;
  padding: 24px;
  box-shadow: 0 10px 40px rgba(0,0,0,.3);
  margin-bottom: 24px;
}

.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 24px;
}

footer {
  text-align: center;
  padding: 32px;
  color: #9ca3af;
  font-size: 14px;
}