*{
margin: 0;
padding: 0;
box-sizing: border-box;
}
html,body{
/* height: 100%; */
width: 100%;
}

body{
    display: flex;
    align-items: center;
    justify-content: center;
    background-color: #efedd6 ;
    flex-direction: column;
    overflow-x: hidden;
}

h1{
    margin: 10px;
}
#box{
    display: flex;
    align-items: center;
    justify-content: center;
    color: #fff;
    background-color: steelblue;
    width: 400px;
    height: 200px;
    margin: 10px;
    border-radius: 10px;
    box-shadow: 2px 4px 5px rgba(0, 0, 0, 0.3);
    transform: translateX(400%);
    transition: transform 0.4s ease;
}
#box:nth-of-type(even){
    transform: translateX(-400%);
}
#box.show{
    transform: translateX(0);
}