html, body {
    height: 100%;
    margin: 0;
    padding: 0;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    display: flex;
    flex-direction: column;
}

#head {
    background-color: rgb(218, 109, 31);
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 10px;
}

#head img {
    width: 28px;
    margin-left: 14px;
    margin-right: 14px;
}

#head a {
    color: aliceblue;
    font-size: 30px;
    font-style: bold;
    text-decoration: none;
}

.hamburger {
    display: none;
    flex-direction: column;
    cursor: pointer;
}

.hamburger span {
    width: 25px;
    height: 3px;
    background-color: white;
    margin: 2px 0;
}

#page {
    display: flex;
    flex-wrap: wrap;
    flex-grow: 1;
}

#nav {
    background-color: white;
    flex: 1;
    min-width: 150px;
}

#nav ul {
    list-style-type: none;
    padding: 0%;
}

#nav li a {
    text-decoration: none;
    color: black;
    font-size: 1rem;
    display: block;
    padding: 10px 40px;
}

#nav li a:hover {
    transition: background-color 0.3s ease;
    background-color: rgba(216, 90, 0, 0.829);
    color: #fff;
}

#content {
    background-image: url("img//Background/Yoga\ wallpaper\ small.jpg");
    background-position: center;
    background-blend-mode: darken;
    background-size: cover;
    background-repeat: no-repeat;
    flex: 3;
    min-height: 400px;
    padding: 20px;
    justify-content: center;
    display: flex;
    align-items: center;
}

#content #PDF {
    background-color: rgba(255, 255, 255, 0.9);
    padding: 20px;
    margin: 50px;
    justify-content: center;
    display: grid;
}

#content #PDF img {
    width: 130px;
}

#content #PDF #img {
    justify-content: center;
    display: flex;
    padding: 30px 30px 0px 30px;
}

#content #PDF #text {
    justify-content: center;
    display: flex;
    font-size: 25px;
}

#content #PDF #button {
    padding: 20px;
}

#content #PDF a{
    padding: 15px;
    background-color: green;
    color: #fff;
    text-decoration: none;
    font-size: 20px;
}

#content #PDF a:hover{
    text-decoration: underline;
}

#ad {
    background-color: white;
    flex: 1;
    min-width: 200px;
}

#footer {
    background-color: #333;
    color: white;
    text-align: center;
    padding: 5px;
    font-size: 0.6rem;
}

@media screen and (max-width: 768px) {
    .hamburger {
        display: flex;
    }

    #nav {
        display: none;
        width: 100%;
        transition: all 0.3s ease-in-out;
    }
    #head img {
        width: 20px;
        margin-left: 5px;
        margin-right: 5px;
    }

    #head b {
        font-size: 20px;
    }

    #nav.active {
        display: block;
    }

    #content #PDF {
        background-color: rgba(255, 255, 255, 0.9);
        padding: 20px;
        margin: 50px;
        justify-content: center;
        display: grid;
    }
    
    #content #PDF img {
        width: 96px;
    }
    
    #content #PDF #img {
        justify-content: center;
        display: flex;
        padding: 30px 30px 0px 30px;
    }
    
    #content #PDF #text {
        justify-content: center;
        display: flex;
        font-size: 17px;
    }
    
    #content #PDF #button {
        padding: 15px;
    }
    
    #content #PDF a{
        padding: 15px;
        background-color: green;
        color: #fff;
        text-decoration: none;
        font-size: 14px;
    }

    #page {
        flex-direction: column;
    }

    #ad {
        min-height: 100px;
    }
}

@media screen and (max-width: 480px) {
    #nav {
        transition: all 0.3s ease-in-out;
    }
}