style.css

html {
    font-family: 'Courier New', Courier, monospace;
    height: 100%;
    width: 100%;
    background: rgb(0,0,0);
    background: linear-gradient(90deg, rgb(20,61,171) 0%, rgba(0,0,0,1) 10%, rgba(0,0,0,1) 90%, rgb(51,198,69) 100%);
}
body {
    height: 100%;
    width: 100%;
    margin: 0;
}
body > div {
    width: 90%;
    margin: auto;
}
#header {
    height: 100px;
}
#main {
    height: calc(100% - 100px - 50px);
}
#footer {
    height: 50px;
    font-size: 10px;
    line-height: 50px;
    color: rgb(100,33,146);
    text-align: center;
}
.nah {
    visibility: hidden;
}
.exit {
    float: right;
}
.midIcon {
    border: 2px solid transparent;
    box-sizing: border-box;
    font-size: 30px;
}
.midIcon:hover {
    background-color: rgba(255,255,255,0.3);
    cursor: pointer;
}
.bigIcon {
    font-size: 40px;
}
.bigIcon:hover {
    font-size: 45px;
    background-color: rgba(255,255,255,0.3);
    cursor: pointer;
}
.bold-text {
    font-weight: bold;
}
/* 2+ lvl */
#menu-top {
    width: 100%;
    height: 100%;
    line-height: 100px;
    font-size: 40px;
    text-align: center;
}
#listView {
    width: 90%;
    margin: auto;
    height: 100%;
    background-color: rgb(252,246,144);
}
#listItems {
    width: 80%;
    margin: auto;
    height: 65px;
    text-align: center;
    padding-top: 5px;
    border-style: none none double none;
    border-width: 10px;
    border-color: rgb(212,159,119);
}
#listItems span {
    display: inline-block;
    width: 60px;
    height: 60px;
}
.selected-item {
    border: 2px solid black !important;
    background-color: rgb(212,159,119);
}
/* 3+ lvl */
#info {
    width: 50%;
    min-height: 100px;
    margin: auto;
    padding-top: 5px;
}
#info > div {
    width: 80%;
    margin: auto;
    text-align: center;
}