Remove unnecessary CSS classes when specifying button icons

Currently we're using *both* ids and classes when specifying the button icons, which seems completely unnecessary and only serves to bloat the CSS code.
In general you always need to be careful about CSS specificity, but in these cases that should not actually be a problem.

Also, while not a button, this patch makes a similar simplification for the `pageNumber`-input.

web/viewer.css

@@ -772,57 +772,57 @@ select {
   inset-inline-start: 12px;
 }
 
-.toolbarButton#sidebarToggle::before {
+#sidebarToggle::before {
   mask-image: var(--toolbarButton-sidebarToggle-icon);
   transform: scaleX(var(--dir-factor));
 }
 
-.toolbarButton#secondaryToolbarToggle::before {
+#secondaryToolbarToggle::before {
   mask-image: var(--toolbarButton-secondaryToolbarToggle-icon);
   transform: scaleX(var(--dir-factor));
 }
 
-#findPrevious.toolbarButton::before {
+#findPrevious::before {
   mask-image: var(--findbarButton-previous-icon);
 }
 
-#findNext.toolbarButton::before {
+#findNext::before {
   mask-image: var(--findbarButton-next-icon);
 }
 
-.toolbarButton#previous::before {
+#previous::before {
   mask-image: var(--toolbarButton-pageUp-icon);
 }
 
-.toolbarButton#next::before {
+#next::before {
   mask-image: var(--toolbarButton-pageDown-icon);
 }
 
-.toolbarButton#zoomOut::before {
+#zoomOut::before {
   mask-image: var(--toolbarButton-zoomOut-icon);
 }
 
-.toolbarButton#zoomIn::before {
+#zoomIn::before {
   mask-image: var(--toolbarButton-zoomIn-icon);
 }
 
-.toolbarButton#presentationMode::before,
+#presentationMode::before,
-.secondaryToolbarButton#secondaryPresentationMode::before {
+#secondaryPresentationMode::before {
   mask-image: var(--toolbarButton-presentationMode-icon);
 }
 
-.toolbarButton#print::before,
+#print::before,
-.secondaryToolbarButton#secondaryPrint::before {
+#secondaryPrint::before {
   mask-image: var(--toolbarButton-print-icon);
 }
 
-.toolbarButton#openFile::before, /* -webkit-non-mozcentral */
+#openFile::before, /* -webkit-non-mozcentral */
-.secondaryToolbarButton#secondaryOpenFile::before /* -webkit-non-mozcentral */ {
+#secondaryOpenFile::before /* -webkit-non-mozcentral */ {
   mask-image: var(--toolbarButton-openFile-icon);
 }
 
-.toolbarButton#download::before,
+#download::before,
-.secondaryToolbarButton#secondaryDownload::before {
+#secondaryDownload::before {
   mask-image: var(--toolbarButton-download-icon);
 }
 
@@ -836,38 +836,38 @@ a.secondaryToolbarButton[href="#"] {
   pointer-events: none;
 }
 
-.toolbarButton#viewBookmark::before,
+#viewBookmark::before,
-.secondaryToolbarButton#secondaryViewBookmark::before {
+#secondaryViewBookmark::before {
   mask-image: var(--toolbarButton-bookmark-icon);
 }
 
-#viewThumbnail.toolbarButton::before {
+#viewThumbnail::before {
   mask-image: var(--toolbarButton-viewThumbnail-icon);
 }
 
-#viewOutline.toolbarButton::before {
+#viewOutline::before {
   mask-image: var(--toolbarButton-viewOutline-icon);
   transform: scaleX(var(--dir-factor));
 }
 
-#viewAttachments.toolbarButton::before {
+#viewAttachments::before {
   mask-image: var(--toolbarButton-viewAttachments-icon);
 }
 
-#viewLayers.toolbarButton::before {
+#viewLayers::before {
   mask-image: var(--toolbarButton-viewLayers-icon);
 }
 
-#currentOutlineItem.toolbarButton::before {
+#currentOutlineItem::before {
   mask-image: var(--toolbarButton-currentOutlineItem-icon);
   transform: scaleX(var(--dir-factor));
 }
 
-#viewFind.toolbarButton::before {
+#viewFind::before {
   mask-image: var(--toolbarButton-search-icon);
 }
 
-.toolbarButton.pdfSidebarNotification::after {
+.pdfSidebarNotification::after {
   position: absolute;
   display: inline-block;
   top: 1px;
@@ -898,59 +898,59 @@ a.secondaryToolbarButton[href="#"] {
   padding-inline-end: 4px;
 }
 
-.secondaryToolbarButton#firstPage::before {
+#firstPage::before {
   mask-image: var(--secondaryToolbarButton-firstPage-icon);
 }
 
-.secondaryToolbarButton#lastPage::before {
+#lastPage::before {
   mask-image: var(--secondaryToolbarButton-lastPage-icon);
 }
 
-.secondaryToolbarButton#pageRotateCcw::before {
+#pageRotateCcw::before {
   mask-image: var(--secondaryToolbarButton-rotateCcw-icon);
 }
 
-.secondaryToolbarButton#pageRotateCw::before {
+#pageRotateCw::before {
   mask-image: var(--secondaryToolbarButton-rotateCw-icon);
 }
 
-.secondaryToolbarButton#cursorSelectTool::before {
+#cursorSelectTool::before {
   mask-image: var(--secondaryToolbarButton-selectTool-icon);
 }
 
-.secondaryToolbarButton#cursorHandTool::before {
+#cursorHandTool::before {
   mask-image: var(--secondaryToolbarButton-handTool-icon);
 }
 
-.secondaryToolbarButton#scrollPage::before {
+#scrollPage::before {
   mask-image: var(--secondaryToolbarButton-scrollPage-icon);
 }
 
-.secondaryToolbarButton#scrollVertical::before {
+#scrollVertical::before {
   mask-image: var(--secondaryToolbarButton-scrollVertical-icon);
 }
 
-.secondaryToolbarButton#scrollHorizontal::before {
+#scrollHorizontal::before {
   mask-image: var(--secondaryToolbarButton-scrollHorizontal-icon);
 }
 
-.secondaryToolbarButton#scrollWrapped::before {
+#scrollWrapped::before {
   mask-image: var(--secondaryToolbarButton-scrollWrapped-icon);
 }
 
-.secondaryToolbarButton#spreadNone::before {
+#spreadNone::before {
   mask-image: var(--secondaryToolbarButton-spreadNone-icon);
 }
 
-.secondaryToolbarButton#spreadOdd::before {
+#spreadOdd::before {
   mask-image: var(--secondaryToolbarButton-spreadOdd-icon);
 }
 
-.secondaryToolbarButton#spreadEven::before {
+#spreadEven::before {
   mask-image: var(--secondaryToolbarButton-spreadEven-icon);
 }
 
-.secondaryToolbarButton#documentProperties::before {
+#documentProperties::before {
   mask-image: var(--secondaryToolbarButton-documentProperties-icon);
 }
 
@@ -991,18 +991,18 @@ a.secondaryToolbarButton[href="#"] {
   margin-inline-start: 7px;
 }
 
-.toolbarField#pageNumber {
+#pageNumber {
   -moz-appearance: textfield; /* hides the spinner in moz */
   text-align: right;
   width: 40px;
 }
-.toolbarField#pageNumber.visiblePageIsLoading {
+#pageNumber.visiblePageIsLoading {
   background-image: var(--loading-icon);
   background-repeat: no-repeat;
   background-position: 3px;
 }
 
-.toolbarField#pageNumber::-webkit-inner-spin-button {
+#pageNumber::-webkit-inner-spin-button {
   -webkit-appearance: none;
 }