/* 导航栏 */
header {
    position: fixed;
    top: 0;
    width: 100%;
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
    z-index: 1000;
    padding: 15px 0;
    transition: var(--transition);
}

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

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--accent-color);
    margin-left: 80px;
}

.nav-links {
    display: flex;
    gap: 25px;
}

.nav-links a {
    text-decoration: none;
    color: var(--text-primary);
    font-weight: 500;
    padding: 5px 10px;
    border-radius: 4px;
    transition: var(--transition);
}

.nav-links a:hover {
    color: var(--accent-color);
    background: rgba(52, 152, 219, 0.1);
}

.nav-right {
    display: flex;
    gap: 15px;
    align-items: center;
}

.theme-selector {
    display: flex;
    gap: 8px;
}

.theme-btn {
    width: 20px;
    height: 20px;
    border-radius: 50%;
    cursor: pointer;
    transition: var(--transition);
    border: 2px solid transparent;
}

.theme-btn:hover {
    transform: scale(1.1);
    box-shadow: 0 3px 8px rgba(0, 0, 0, 0.3);
}

.theme-btn.active {
    border-color: var(--accent-color);
}

.theme-default {
    background: linear-gradient(135deg, #f8fafc, #e2e8f0);
}

.theme-dark-btn {
    background: linear-gradient(135deg, #0f172a, #1e293b);
}

.theme-high-contrast-btn {
    background: linear-gradient(135deg, #000000, #222222);
}

.theme-darcula-btn {
    background: linear-gradient(135deg, #2b2b2b, #3c3f41);
}

/* FPS显示 */
#fps {
    position: fixed;
    top: 10px;
    left: 10px;
    background: rgba(0, 0, 0, 0.6);
    color: white;
    padding: 5px 10px;
    border-radius: 4px;
    font-size: 12px;
    z-index: 2000;
    font-family: monospace;
}