html {
    width: 100%;
    height: 100%;
    background-color: #2a323d;
    color: white;
    font-weight: normal;
    line-height: 1.5;
}

#title {
    text-align: center;
}

section {
    width: 95%;
    max-width: 1200px;
    margin: auto;
    background-color: #242a33;
    box-shadow: 2px 2px 3px #222;
    border-radius: 2px;
    padding: 10px;
    margin-bottom: 20px;
}

section img {
    margin: auto;
    display: block;
}

section table {
    margin: auto;
    min-width: 50%;
    text-align: left;
}

section button {
    margin: 10px;
    background: none;
    outline: none;
    border: solid 1px grey;
    color: white;
    cursor: pointer;
    transition: background .2s;
    border-radius: 10px;
    padding: 4px 8px;
    font-size: large;
    transition: .2s;
}

section button:hover {
    background: #2a323d;
}

section .field {
    display: flex;
    margin: 8px 0;
    border-bottom: solid 2px #2a323d;
    padding-bottom: 8px;
}

section .field > * {
    flex-basis: 50%;
}

section .field > :first-child {
    flex-shrink: 1;
}

#footer {
    font-size: .8em;
    width: 95%;
    max-width: 1200px;
    margin: auto;
    margin-top: 20px;
    padding-bottom: 10px;
    text-align: center;
}

#footer .link {
    color: #ffab40;
}

input {
    background: none;
    border: none;
    border-bottom: solid 1px grey;
    transition: border .2s;
    color: white;
    font-size: medium;
    min-width: 0;
}

input:focus {
    border-bottom-color: white;
    outline: none;
}

input:invalid {
    color: red;
}

input[type=color] {
    padding: 0;
    border-bottom: none;
}

input[type=checkbox],
input[type=radio] {
    display: none;
}

input[type=checkbox] + label,
input[type=radio] + label {
    display: block;
    cursor: pointer;
}

input[type=radio] + label:not(:last-child) {
    margin-bottom: 8px;
}

input[type=checkbox] + label:before,
input[type=radio] + label:before {
    border: 1px solid grey;
    display: inline-block;
    box-sizing: border-box;
    width: 24px;
    height: 24px;
    vertical-align: bottom;
    color: transparent;
    transition: .2s;
    text-align: center;
    margin-right: 8px;
}

input[type=checkbox] + label:before {
    content: "\2714";
    border-radius: 3px;
}

input[type=radio] + label:before {
    content: "\25CF";
    border-radius: 50%;
    font-size: smaller;
}

input[type=checkbox] + label:active:before,
input[type=radio] + label:active:before,
button:active {
    transform: translateY(-10px);
    border-color: white;
}

input[type=checkbox]:checked + label:before,
input[type=radio]:checked + label:before {
    background-color: #2a323d;
    color: #fff;
}

#reset {
    border-bottom: none;
    text-transform: uppercase;
    border-radius: 10px;
    padding: 4px 8px;
    cursor: pointer;
    border: solid 2px red;
    transition: background .2s;
}

#reset:hover {
    background: red;
}

.button-row {
    text-align: center;
}

.instruction {
    margin: 0;
}

/* 
 * Fun fact: every selector using a #id selector was originally written using 
 *  other types of selectors, apart from this one.
 * I usually try to avoid using IDs altogether - even in Javascript I usually
 *  use React, so I don't even use IDs there - but had to add a bunch here to
 *  meet the requirements :/
 */
.instruction + #target {
    box-shadow: 2px 2px 3px #222;
    margin: 10px auto;
}

@keyframes rotate {
    from {
        transform: rotateZ(0);
    }
    to {
        transform: rotateZ(360deg);
    }
}

@keyframes popout {
    0% {
        box-shadow: 0 0 red, 0 0 red, 0 0 red, 0 0 red, 0 0 red, 0 0 red, 0 0 red, 0 0 red;
        transform: translateX(0) translateY(0);
    }
    50% {
        box-shadow: 1px -1px red, 2px -2px red, 3px -3px red, 4px -4px red, 5px -5px red, 6px -6px red, 7px -7px red, 8px -8px red;
        transform: translateX(-8px) translateY(8px);
    }
    100% {
        box-shadow: 0 0 red, 0 0 red, 0 0 red, 0 0 red, 0 0 red, 0 0 red, 0 0 red, 0 0 red;
        transform: translateX(0) translateY(0);
    }
}

@keyframes jump {
    0% {
        transform: translateY(0);
    }
    50% {
        transform: translateY(-20px);
    }
    100% {
        transform: translateY(0);
    }
}