header { 
    background:black;
    color:yellow;
    text-align:left;
    position:fixed;
    width:60px;
    height:100%;
    margin-top:50px;
    border-right:1px solid grey;
    z-index:999;
}
body {
    margin:0px;
}
.headerbtn:active {
    background:white;
    color:black;
    filter:none;
}
.headerbtn {
    text-decoration:none;
    background:transparent;
    width:100%;
    display:block;
    padding-top:10px;
    padding-bottom:10px;
    text-align:center;
    height:auto;
    filter:
        invert(100%)
        sepia(100%)
        saturate(1000%)
        hue-rotate(2deg)
        brightness(95%)
        contrast(105%);
}
.button {
    text-decoration:none;
    padding:9px;
    cursor:pointer;
    background:black;
    border:1px solid white;
    border-radius:5px;
    color:white;
    font-size:70%;
    transition:all 0.3s;
}
.button:hover {
    background:white;
    color:black;
    border:1px solid black;
}
.dashboard {
    height:20px;
}
.courses {
    height:30px;
}
.active {
    background:white !important;
    color:black !important;
    filter:none !important;
}
#gamesContainer {
    display: flex;
    flex-wrap: wrap;
    gap: 10px; 
    margin-left:70px;
}
.gamesbutton {
    padding: 10px 15px;
    font-size: 14px;
    cursor: pointer;
    border: 1px solid #333;
    border-radius: 5px;
    background: #f0f0f0;
    white-space: nowrap;
}
.gamesbutton:hover {
    background: #ddd;
}
center {
    margin-left:70px;
}
input {
    cursor:text !important;
}
#qrPreview { 
    width: 100%; 
    max-width: 420px; 
    border:10px solid white;
    background:white;
    border-radius:20px;
}
.logo-preview { 
    width: 48px; 
    height: 48px; 
    border-radius: 12px; 
    background: #f0f2f7; 
    display: inline-grid; 
    place-items: center; 
    overflow: hidden; 
    border: 1px dashed #cbd2e1; 
}
.qr-stage { 
    display: grid; 
    place-items: center; 
    background: transparent; 
    border-radius: 18px; 
    padding: 16px; 
}
.wrap { 
    max-width: 1100px; 
    margin: 0 auto; 
    display: grid; 
    grid-template-columns: 1.2fr 1fr; 
    gap: 24px; 
}
.card { 
    background: #fff; 
    border-radius: 16px; 
    padding: 16px; 
    box-shadow: 0 8px 24px rgba(0,0,0,0.08); 
}