tt-rss/lib/dijit/themes/nihilo/form/Select.css

.nihilo .dijitSelectError .dijitButtonContents,
.nihilo .dijitSelectHover .dijitArrowButton,
.nihilo .dijitSelectActive .dijitArrowButton,
.nihilo .dijitSelectOpened .dijitArrowButton,
.nihilo .dijitSelectDisabled .dijitArrowButton,
.nihilo .dijitSelectReadOnly .dijitArrowButton {
	background: transparent none;
}

.nihilo .dijitSelect .dijitArrowButton {
	background: #bcd5f0 url("../images/buttonEnabled.png") repeat-x top left;
	border-width: 0;
}

/* Mirror DropDownButton */
.nihilo .dijitSelectDisabled,
.nihilo .dijitSelectDisabled TD {
    border-color: #dedede !important;
    background:#fafafa url("../images/buttonDisabled.png") top repeat-x;
}
.dj_ie .nihilo .dijitSelectDisabled  TD * {
	filter: gray() alpha(opacity=50);
}

.nihilo .dijitSelectHover,
.nihilo .dijitSelectHover TD {
    color:#000;
    background:#fcfcfc url("../images/buttonHover.png") repeat-x top left;
}

.nihilo .dijitSelectActive,
.nihilo .dijitSelectOpened,
.nihilo .dijitSelectActive TD,
.nihilo .dijitSelectOpened TD {
    border-color:#dedede !important;
    background: #f5f5f5 url("../images/buttonActive.png") top left repeat-x;
}

/* Make the menu look more combobox-like */
.nihilo .dijitSelectMenu td {
	padding: 0;
}
.nihilo .dijitSelectMenu .dijitMenuItemLabel,
.nihilo .dijitSelectMenu .dijitMenuArrowCell {
	padding: 0.1em 0.2em;
}