/* 公共样式 - 全局设置 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(135deg, #0a0e27 0%, #1a1f3a 100%);
    color: #e0e0e0;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

/* 头部导航 */
header {
    background: rgba(26, 31, 58, 0.9);
    border-bottom: 1px solid rgba(100, 200, 255, 0.3);
    padding: 20px 0;
    position: sticky;
    top: 0;
    z-index: 100;
}

.header-content {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

header h1 {
    font-size: 28px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    cursor: pointer;
}

nav {
    display: flex;
    gap: 15px;
}

/* 按钮样式 */
.btn-primary, .btn-secondary {
    padding: 12px 24px;
    border: none;
    border-radius: 8px;
    font-size: 16px;
    cursor: pointer;
    transition: all 0.3s;
}

.btn-primary {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(102, 126, 234, 0.4);
}

.btn-secondary {
    background: rgba(255, 255, 255, 0.1);
    border: 1px solid rgba(100, 200, 255, 0.3);
    color: #e0e0e0;
}

.btn-secondary:hover {
    background: rgba(255, 255, 255, 0.15);
    border-color: #667eea;
}

/* 主内容区 */
main {
    flex: 1;
    max-width: 1200px;
    width: 100%;
    margin: 40px auto;
    padding: 0 20px;
}

/* 页脚 */
footer {
    text-align: center;
    padding: 20px;
    color: #888;
    background: rgba(26, 31, 58, 0.5);
}

footer a {
    color: #667eea;
    text-decoration: none;
}

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

/* 隐藏类 */
.hidden {
    display: none !important;
}