nav {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: #34495e;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 10px 0;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.2);
    position: relative; /* For the pseudo-element */
    overflow: hidden; /* Hide overflow from pseudo-element */
    border-radius: 8px; /* added */
}

    /*nav::before {
        content: '';
        position: absolute;
        top: 0;
        left: -100%;
        width: 300%;
        height: 100%;
        background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.1), transparent);
        animation: shimmer 5s linear infinite;
    }*/

@keyframes shimmer {
    0% {
        transform: translateX(0);
    }

    100% {
        transform: translateX(-66.66%);
    }
}

nav a {
    color: #ecf0f1;
    text-decoration: none;
    padding: 10px 20px;
    margin: 0 10px;
    position: relative; /* For the underline effect */
    transition: color 0.3s ease;
    font-weight: bold;
}

    nav a:hover {
        color: #1abc9c;        
    }

    /*nav a::before {
        content: '';
        position: absolute;
        width: 100%;
        height: 2px;
        bottom: 0;
        left: 0;
        background-color: #1abc9c;
        visibility: hidden;
        transform: scaleX(0);
        transition: all 0.3s ease-in-out 0s;
    }*/

    nav a:hover::before {
        visibility: visible;
        transform: scaleX(1);
    }

.nav-container {
    /*width: 80%;*/
    /*max-width: 1200px;*/
    /*margin: 0 auto;*/
    display: flex;
    justify-content: center;
    width: min(210mm, 90%); /* added */
    border-radius: 8px; /* added */
}