header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px 60px;
    background: var(--card);
    box-shadow: 0 1px 4px var(--shadow);
    position: sticky;
    top: 0;
    z-index: 10;
}

header .logo {
    font-size: 25px;
    font-weight: 700;
    color: #1E88E5;
    display: flex;
    align-items: center;
    gap: 8px;
}

nav a {
    margin: 0 14px;
    text-decoration: none;
    color: #0f172a;
    font-weight: 500;
}

@media (max-width: 600px) {
    header {
        padding: 16px 20px;
    }

    nav {
        display: none;
    }
}