.topnav {
    background: rgba(15, 23, 42, 0.6);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--card-border, rgba(255, 255, 255, 0.08));
    position: sticky;
    top: 0;
    z-index: 100;
    width: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-wrap: wrap;
    padding: 0.5rem 1rem;
}

.topnav a {
    float: left;
    display: block;
    color: var(--text-main, #f8fafc);
    text-align: center;
    padding: 0.75rem 1.25rem;
    text-decoration: none;
    font-size: 1rem;
    font-weight: 500;
    border-radius: 8px;
    margin: 0.25rem;
    transition: all 0.2s ease;
}

.topnav a:hover {
    background-color: rgba(255, 255, 255, 0.1);
    color: var(--primary, #00f2fe);
}

.topnav a.active {
    background: linear-gradient(135deg, rgba(0, 242, 254, 0.2), rgba(79, 172, 254, 0.2));
    color: var(--primary, #00f2fe);
    border: 1px solid rgba(0, 242, 254, 0.3);
}

.topnav .icon {
    display: none;
}

@media screen and (max-width: 600px) {
    .topnav {
        justify-content: space-between;
    }
    
    .topnav a:not(:first-child) {
        display: none;
    }

    .topnav a.icon {
        float: right;
        display: block;
        background: transparent;
        border: none;
    }
    
    .topnav.responsive {
        flex-direction: column;
        align-items: stretch;
    }
    
    .topnav.responsive a {
        display: block;
        text-align: left;
        margin: 0.25rem 0;
    }
}