.Page404 {
    text-align: center;
    min-height: 100vh;
    display: block;
}

.PageTable {
    display: table;
    vertical-align: middle;
    width: 100%;
}

.PageCell {
    display: table-cell;
    height: 100vh;
    vertical-align: middle;
    font-size: 200%;
    color: rgba(0,0,0,0.5);
}

.Number {
    font-size: 800%;
    line-height: 0.8;
    font-weight: bold;
}

.back {
    display: inline-block;
    padding: 1.5%;
    margin: 1%;
    color: #fff;
    background-color: rgba(0,0,0,0.5);
    border-radius: 4px;
    cursor: pointer;
    	-webkit-transition-property: background-color;
	-moz-transition-property: background-color;
	 -ms-transition-property: background-color;
	  -o-transition-property: background-color;
	     transition-property: background-color;
	-webkit-transition-duration: 0.3s;
	-moz-transition-duration: 0.3s;
	 -ms-transition-duration: 0.3s;
	  -o-transition-duration: 0.3s;
	     transition-duration: 0.3s
}

.back:hover {
    background-color: rgba(0,0,0,0.9);
}