a.highlight {
    background-color: #e4ab5b;
}

.useful-block {
    text-align: center;
    position: fixed;
    right: 0;
    bottom: 0;
    background-color: white;
    opacity: 0.9;
    padding: 5px;
}
.useful-block > i {
    margin-left: 10px;
    cursor: pointer;
}
.useful-block > i.voted {
    color: #4CAF50;
}
.useful-block:has(i.voted) {
    color: #babdb6;
}
.useful-block:has(i.voted) > i {
    cursor: default;
    pointer-events: none;
}