body {
    color: #fff;
    background-color: #000;
    font-family: sans-serif;
    display: flex;
    padding: 0;
    margin: 0;
}

h1 {
    font-size: 28px;
}

* {
    box-sizing: border-box;
}

.scene {
    width: 100%;
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    overflow: auto;
}

.hidden {
    display: none;
}

.container {
    width: 100%;
    max-width: 900px;
    max-width: 100vh;
    max-width: calc(100vh - 120px);
    text-align: center;
}

.btn {
    background-color: transparent;
    background-image: none;
    color: #fff;
    text-align: center;
    border: 1px solid transparent;
    padding: 10px;
    font-size: 18px;
    text-transform: uppercase;
    cursor: pointer;
    text-decoration: none;
    display:inline-block;
}

.btn.active {
    border-color: #999;
}

.btn.hidden {
    display: none;
}

.btn:hover {
    border-color: #fff;
}

.color-picker {
    display: inline-block;
}

.color-picker.hidden {
    display: none;
}

.color-picker > span {
    border: 1px solid #fff;
    padding: 5px;
    display: block;
}
.color-picker > span:hover {
    border-color: #fc9;
}

.color-picker > input:checked + span {
    background-color: #999;
}

.color-picker > span > i {
    width: 15px;
    height: 15px;
    display: block;
}

.btn.picker {
    border: 1px solid #fff;
    display: block;
    padding: 0;
    width: 27px;
    height: 27px;
    position: relative;
}

.btn.picker:hover {
    border-color: #fc9;
}

.btn.picker > span {
    display: block;
    font-size: 15px;
    width: 25px;
    height: 25px;
    line-height: 25px;
    position: absolute;
    left: 0;
    top: 0;
}

.row {
    width: 100%;
    display: flex;
    flex-wrap: nowrap;
}

.row.hidden {
    display: none;
}

.row.center {
    align-items: center;
}

.col {
    width: 100%;
    padding: 0;
    margin: 0;
    flex-grow: 1;
    flex-basis: 0;
}

.col-auto {
    flex: 0 0 auto;
    width: auto;
}

.col.center {
    text-align: center;
}

.light {
    display: block;
    background-color: transparent;
    background-image: none;
    border: 1px solid #999;
    margin: 0;
    width: 100%;
    padding-bottom: 100%;
}

.light.on {
    background-color: #fff;
}
.light.init {
    background-image: linear-gradient(45deg, transparent 50%, #f00 50%);
}

.light:hover {
    border: 1px solid #fc9;
    box-shadow: inset 0 0 10px #fc9;
}

.message {
    position: fixed;
    width: 100%;
    height: 100%;
    left: 0;
    top: 0;
    display: flex;
    justify-content: center;
    align-items: center;
    background-color: rgba(0, 0, 0, 0.8);
}

.box {
    border: 1px solid #fff;
    padding: 20px;
}

.big {
    font-size: 28px;
}

.white {
    background-color: #fff;
}
.red {
    background-color: #f00;
}
.green {
    background-color: #0f0;
}
.blue {
    background-color: #00f;
}
.cyan {
    background-color: #0ff;
}
.yellow {
    background-color: #ff0;
}
.magenta {
    background-color: #f0f;
}
.black {
    background-color: #000;
}

.dropdown {
    position: relative;
    text-align: left;
    margin-left: 10px;
}

.dropdown > .dropdown-display {
    padding: 5px 15px;
    border: 1px solid #888;
    border-bottom-color: #fff;
}

.dropdown > .dropdown-menu {
    display: none;
    position: absolute;
    left: 0;
    top: 100%;
    width: 100%;
    max-height: 300px;
    overflow: auto;
    background-color: #000;
    border: 1px solid #fff;
    border-top: none;
    z-index: 10;
}

.dropdown > .dropdown-menu > .dropdown-item {
    padding: 5px 15px;
}

.dropdown > .dropdown-menu > .dropdown-item::before {
    content: '';
    display: inline-block;
    border-left: 8px solid transparent;
    border-top: 4px solid transparent;
    border-bottom: 4px solid transparent;
}

.dropdown-open > .dropdown-menu {
    display: block;
}

.code-block {
    overflow: hidden;
    font-size: 10px;
    word-break: keep-all;
    white-space: nowrap;
    text-overflow: ellipsis;
}

.level-button {
    color: #fff;
    text-decoration: none;
    display: block;
    text-align: left;
}

.level-button:hover {
    color: #fc9;
}

.level-button::before {
    content: '';
    display: inline-block;
    width: 1.5em;
    height: 1.5em;
    line-height: 1.5em;
    vertical-align: middle;
}

.level-button.solved::before {
    content: '\2714';
}
.level-button.ideal::before {
    content: '\1F3C6';
}
.level-button.improved::before {
    content: '\1F632';
}