pm-controls/source/app/controls/components/base/drop-down/drop-down.css

ProModel Controls

.dropdown-container {
    position: fixed;
    z-index: 2000;
}

.dropdown-control {
    position: absolute;    
    box-shadow: 0px 1px 3px 0px rgba(0,0,0,0.2), 0px 1px 1px 0px rgba(0,0,0,0.14), 0px 2px 1px -1px rgba(0,0,0,0.12);    
    background-color: white;
}

.dropdown-top-border {
    border-top: 1px solid #ECEFF1;
}

.legacy-dropdown-container {
    width: 100%;
}