:root {
    --darkpink: #ff99aa;
}

html, body {
    background: lightgray;
    color: slategray;
    font-family: sans-serif;
    font-size: 16px;
}

button {
    font-size: inherit;
}

h1, h4 {
    font-weight: normal;
    margin: 0;
}

button,
input,
label,
textarea {
    color: darkslategray;
    font-family: inherit;
    font-size: inherit;
}

a,
button,
label {
    cursor: pointer;
}

[type="checkbox"] {
    width: 1.3em;
    height: 1.3em;
    margin: 0 .5em;
    vertical-align: text-bottom;
    border: 1px solid slategray;
    background: mistyrose;
    border-radius: .333em;
    -webkit-appearance: none;
       -moz-appearance: none;
            appearance: none;
}
[type="checkbox"]:hover {
    background-color: var(--darkpink);
}
[type="checkbox"]:checked {
    background: url("checkmark.png") center no-repeat;
    background-color: var(--darkpink);
    background-size: 80%;
}
[type="checkbox"]:focus {
    outline: none;
    border-color: royalblue;
    box-shadow: 0 0 0px 1px royalblue, 0 0 0px 3px white;
}

main {
    line-height: 2;
    text-align: center;
}

main header,
main article,
main footer {
    margin: 1em;
}

main header {
    font-size: 2em;
}

header button {
    background: mistyrose;
    border: 1px solid pink;
    border-radius: 50%;
    color: pink;
    padding: .5em .7em;
    box-shadow: 0 0 6px 0 purple;
    text-shadow: 1px 1px 3px purple;
    width: 7.5em;
    height: 2.5em;
}

header button:hover {
    background: radial-gradient(mistyrose 48%, pink 86%);
    border-color: purple;
}

header button:focus {
    border-color: royalblue;
    border-width: 2px;
    box-shadow: inset 2px 2px 0 1px white, 2px 2px 0 1px white;
    outline: none;
}

footer button {
    border: 1px solid slategray;
    background: mistyrose;
    border-radius: .333em;
    padding: .1em .333em;
}
footer button:hover {
    background-color: var(--darkpink);
    color: white;
}
footer button:focus {
    outline: none;
    border-color: royalblue;
    box-shadow: 0 0 0px 1px royalblue, 0 0 0px 3px white;
}

textarea {
    display: block;
    margin: 0 auto;
    background: #fff9;
    border-radius: .5em;
    border: 1px solid slategray;
    padding: .2em .3em;
    width: 27em;
    min-height: 13em;
}

textarea:focus {
    outline: none;
    border-color: royalblue;
    box-shadow: 0 0 0px 1px royalblue, 0 0 0px 3px white;
}