* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

/* content */
.content {
    width: 100%;
    height: 100vh;
    background: url(https://images.unsplash.com/photo-1551334787-21e6bd3ab135?ixlib=rb-1.2.1&auto=format&fit=crop&w=1502&q=80);
    background-position: center;
    background-size: cover;
    color: white;
    text-align: center;
    position: relative;
}

.sec2 {
    background: url(https://images.unsplash.com/photo-1551309292-e185c0b6e22a?ixlib=rb-1.2.1&auto=format&fit=crop&w=1500&q=80);
    background-position: center;
    background-size: cover;
}
/*
h1 {
    font-size: 50px;
    position: absolute;
    width: 100%;
    top: 50%;
    left: 50%;
    transform: translateX(-50%) translateY(-50%);
}
*/

.menu {
    text-align: right;
    position: fixed;
    width: 100%;
    z-index: 200;
}
/* I hide the checkbox because I only need the label */
#check {
    display: none;
}







.button {
    padding-right: 3px;
    top: 18px;
    left: 17px;
    width: 48px;
    height: 48px;
    background: rgba(255, 255, 255, .95);
    padding: 12px;
    display: inline-block;
    cursor: pointer;
    transition: all 0.2s ease-in;
    padding-top: 13px;
    line-height: 8px;
    text-align: left;
    position: fixed;
    z-index: 201;
}

    .button:hover {
        background: #DBDBDB;
    }

    .button span {
        height: 3px;
        width: 100%;
        margin-bottom: 6px;
        background: #191919;
        display: inline-block;
        transition: all 0.5s cubic-bezier(.62,.43,.35,1.47);
    }


/* toggle icon animation */
#check:checked ~ .button span:nth-child(1) {
    width: 100%;
    transform: rotate(45deg) translateY(6px) translateX(6px);
}

#check:checked ~ .button span:nth-child(2) {
    width: 0;
}

#check:checked ~ .button span:nth-child(3) {
    width: 100%;
    transform: rotate(-45deg) translateY(-7px) translateX(7px);
}


/* the nav height is set to 0 when the navbar is closed */

nav {
    text-align: left;
    overflow: hidden;
    transition: all 0.4s ease;
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    background: #ffffff;
    height: 0;
}

    nav a {
        text-decoration: none;
        color: #0c1019;
        display: block;
        font-size: 15px;
        transition: all 0.4s cubic-bezier(.22,.43,.35,1.5);
        opacity: 0;
        transform: scale(0);
        transform-origin: top;
        text-align: center;
        border-bottom: 1px solid #e4e4e4;
    }

        nav a:hover {
            background: #DBDBDB;
        }

/* the nav height will be set to the height in pixels that would have for default, using height:auto won't work but you can put that value in pixels creating the slide*/
#check:checked ~ nav {
    height: 350px;
}

    #check:checked ~ nav a {
        padding: 10px;
        opacity: 1;
        transform: scale(1);
    }

/* you can edit the direction where the slide starts, changing the height animation to width, but it will take some changes.
for example:

nav{
    width: 0%;
    background: #ffffff;
    height: auto;
    max-height 144px;
    opacity: 0;
}

#check:checked ~ nav{
    width: 100%;
    opacity: 1;
} 

*/