index.css

*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
}

body {
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100svh;
    overflow: hidden;
    background-color: #222;
}

canvas {
    width: min(100svw, 100svh);
    height: min(100svw, 100svh);
    background-color: #333;
}

div {
    position: fixed;
    top: 10px;
    right: 10px;
    display: grid;
    gap: 10px;
    grid-auto-rows: 20px;
    grid-template-columns: 1fr;
}

input {
    position: relative;
    width: 20px;
    height: 20px;
    appearance: none;
}

input::before {
    content: "";
    display: block;
    position: absolute;
    width: 100%;
    height: 100%;
    border: 2px solid #FD0;
    background-color: #0000;
    border-radius: 3px;
}

input:checked::before {
    background-color: #FD0;
}

input:checked::after {
    content: "";
    display: block;
    position: absolute;
    left: 50%;
    top: 50%;
    width: 5px;
    height: 10px;
    transform: translate(-50%, -60%) rotate(45deg);
    border-width: 2px;
    border-color: #000;
    border-style: none solid solid none;
}