* { margin: 0; padding: 0; box-sizing: border-box; }

body { 
    min-height: 100vh; 
    display: flex; 
    flex-direction: column;
    align-items: center; 
    justify-content: center;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
}

/* Header */
.header {
    background: rgba(0,0,0,0.1);
    color: white;
    padding: 15px 0;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 100;
    backdrop-filter: blur(10px);
}

.header-inner {
    max-width: 800px;
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    align-items: center;
    gap: 15px;
}

.back-link {
    color: white;
    text-decoration: none;
    font-size: 14px;
    padding: 8px 15px;
    border-radius: 20px;
    background: rgba(255,255,255,0.2);
    transition: background 0.3s;
}

.back-link:hover {
    background: rgba(255,255,255,0.3);
}

.page-title {
    font-size: 18px;
    font-weight: 600;
    flex: 1;
    text-align: center;
    color: white;
}

/* 导航栏右侧控制区 */
.header-controls {
    display: flex;
    align-items: center;
    gap: 10px;
    margin-left: auto;
}

.box {
    text-align: center;
    color: white;
    padding: 20px;
    margin-top: 60px;
}

.spinner {
    width: 50px;
    height: 50px;
    border: 4px solid rgba(255,255,255,0.3);
    border-top-color: white;
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin: 0 auto 20px;
}

@keyframes spin { to { transform: rotate(360deg); } }

.browser-name {
    font-size: 18px;
    margin-bottom: 10px;
}

.hint {
    font-size: 14px;
    opacity: 0.8;
    margin-top: 15px;
}

.links {
    margin-top: 30px;
    padding-top: 20px;
    border-top: 1px solid rgba(255,255,255,0.3);
}

.links a {
    color: white;
    text-decoration: underline;
    font-size: 14px;
    margin: 0 10px;
    opacity: 0.8;
    cursor: pointer;
}

.links a:hover { opacity: 1; }