nav .menu-nav {
    display: flex;
    list-style: none;
}

nav .menu-nav li {
    margin: 0 1rem;
}

.main-font {
    font-family: 'Roboto Condensed', sans-serif;
}

.content {
    display: flex;
    justify-content: center;
    align-items: center;
    text-align: center;
    margin-top: 2rem;
    flex-grow: 1;
}

.content img {
    margin: 1rem;
    border-radius: 5%;
    box-shadow: 3px 3px 3px #9b9b9b;
}

.content p {
    margin: 1rem;
    font-family: "IBM Plex Sans Thai", sans-serif;
    font-weight: 400;
    font-style: normal;
    color: #dfdfdf;
}

@media (max-width: 768px) {
    nav .menu-nav {
        display: none;
        flex-direction: column;
    }
    
    nav .menu-nav.active {
        display: flex;
    }

    .menu-toggle {
        display: block;
        cursor: pointer;
        font-size: 1.5rem;
    }
}

@media (min-width: 769px) {
    .menu-toggle {
        display: none;
    }

    nav .menu-nav {
        display: flex;
    }
}

.flex-container {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
}

.content {
    margin: 1rem;
}

.popup {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 1000;
}

.popup-content {
    background: #313131;
    padding: 2rem;
    margin: 2rem;
    border-radius: 5px;
    text-align: center;
}

.popup input[type="password"] {
    padding: 0.5rem 1rem;
    margin-top: 1rem;
    margin-right: 1rem;
    border-radius: 5px;
    color: #313131;
    border: none;
    margin-bottom: 1rem;
}

.popup button {
    padding: 0.5rem 1rem;
    background: #007bff;
    border: none;
    color: #fff;
    border-radius: 5px;
    cursor: pointer;
}

.responsive-img {
    width: 100%;
    height: auto;
    max-width: 100%;
}

@media (min-width: 768px) {
    .responsive-img {
        width: 600px;
    }
}