.dropdown {
    position: relative;
    font-size: 14px;
    color: #333;
}

.dropdown .dropdown-list {
    padding: 12px;
    background: #fff;
    position: absolute;
    top: 40px;
    left: 2px;
    right: 2px;
    box-shadow: 0 1px 2px 1px rgba(0, 0, 0, 0.15);
    transform-origin: 50% 0;
    transform: scale(1, 0);
    transition: transform 0.15s ease-in-out 0.15s;
    max-height: 66vh;
    overflow-y: scroll;
    z-index:10;
}

.dropdown .dropdown-option {
    display: block;
    padding: 8px 12px;
    opacity: 0;
    transition: opacity 0.15s ease-in-out;
    text-align:left;
}

.dropdown .dropdown-label {
    display: block;
    height: 38px;
    background: #fff;
    border: 1px solid #ccc;
    padding: 12px 12px;
    line-height: 1;
    cursor: pointer;
    text-align:left;
}

.dropdown .dropdown-label:before {
    content: "▼";
    float: right;
}

.dropdown.on .dropdown-list {
    transform: scale(1, 1);
    transition-delay: 0s;
}

    .dropdown.on .dropdown-list .dropdown-option {
        opacity: 1;
        transition-delay: 0.2s;
    }

.dropdown.on .dropdown-label:before {
    content: "▲";
}

.dropdown [type=checkbox] {
    position: relative;
    top: -1px;
    margin-right: 4px;
}