.expand-button { min-width: 0; width: 40px; height: 28px; margin: 0; padding: 4px; border-radius: 5px; background-color: transparent; -moz-context-properties: fill, fill-opacity; fill: var(--fill-secondary); &:hover { background-color: var(--fill-quinary); } &[open="true"] { background-color: var(--fill-quarternary); } &:disabled { background-color: transparent; fill: var(--fill-tertiary); .toolbarbutton-menu-dropmarker { fill: var(--fill-tertiary); } } .toolbarbutton-menu-dropmarker { display: block; visibility: visible; background-image: url("chrome://zotero/skin/chevron-6.svg"); background-repeat: no-repeat; background-position: center; fill: var(--fill-secondary); width: 8px; height: 8px; } }