@keyframes fadeIn {
    0% {
        opacity: 0;
    }
    100% {
        opacity: 1;
    }
}

:root {
    --main-bg-color: #4315df;
    --main-text-color: #b8e71a;
    --app-height: 100%;

    font-family: Inter, system-ui, Avenir, Helvetica, Arial, sans-serif;
    line-height: 1.5;
    font-weight: 400;

    color-scheme: light dark;
    color: var(--main-text-color);
    background-color: var(--main-bg-color);

    font-synthesis: none;
    text-rendering: optimizeLegibility;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    -webkit-text-size-adjust: 100%;
}

body {
    margin: 0;
    display: flex;
    justify-content: center;
    align-items: center;
    width: 100vw;
    height: 100vh;
    height: var(--app-height);
}

h1 {
    font-size: 3.2em;
    line-height: 1.4;
    margin: 0;
    padding-bottom: 20px;
    text-align: center;
}

form {
    text-align: center;
}

#app {
    margin: auto;
    opacity: 0;
}

.fadeIn {
    animation-name: fadeIn;
    animation-duration: 0.6s;
    animation-fill-mode: forwards;
}

.container {
    display: inline-block;
    position: relative;
    padding: 18px;
    cursor: pointer;
    -webkit-user-select: none;
    -moz-user-select: none;
    -ms-user-select: none;
    user-select: none;
}

.container input {
    position: absolute;
    opacity: 0;
    cursor: pointer;
}

.container .svg {
    width: 100px;
    padding: 20px;
    border-radius: 8px;
    border: 2px dashed var(--main-text-color);
}

.container .svg * {
    fill: var(--main-text-color);
}

.container input:checked ~ .svg {
    background-color: var(--main-text-color);
    border: 2px dashed var(--main-text-color);
}

.container input:disabled ~ .svg {
    opacity: 0.8;
}

.container input:checked ~ .svg * {
    fill: var(--main-bg-color);
}

@media screen and (max-height: 640px) {
    h1 {
        font-size: 2.4em;
    }

    .container .svg {
        width: 60px;
        height: 60px;
    }
}