body {
    background-color: black;
}

html,
body,
div#game {
    margin: 0;
    padding: 0;
    min-height: 100vh;
}

div#game {
    display: flex;
    justify-content: center;
    align-items: center;
}

.nothing-button {
    display: block;
    margin: 30px auto;
    padding: 0;
    position: relative;
    overflow: hidden;
    border-width: 0;
    outline: none;
    border-radius: 2px;
    box-shadow: 0 1px 4px rgba(0, 0, 0, 0.6);
    background-color: rgb(0, 128, 0);
    color: white;
    transition: background-color 0.3s;
}

.nothing-button:hover,
.nothing-button:focus {
    background-color: rgb(40, 158, 40);
}

.nothing-button > * {
    position: relative;
}

.nothing-button span {
    display: block;
    padding: 12px 24px;
    user-select: none;
}

.nothing-button:before {
    content: "";
    position: absolute;
    top: 50%;
    left: 50%;
    display: block;
    width: 0;
    padding-top: 0;
    border-radius: 100%;
    background-color: rgba(255, 255, 255, 0.3);
    transform: translate(-50%, -50%);
}

.nothing-button:active:before {
    width: 120%;
    padding-top: 120%;
    transition: width 0.2s ease-out, padding-top 0.2s ease-out;
}