enhance(frontend): improve usability on touch device

packages/frontend/src/style.scss

@@ -81,6 +81,11 @@ html {
 	&.useSystemFont {
 		font-family: system-ui;
 	}
+
+	&:not(.forceSelectableAll) {
+		user-select: none;
+		-webkit-user-select: none;
+	}
 }
 
 html._themeChanging_ {
@@ -120,6 +125,8 @@ a {
 textarea, input {
 	tap-highlight-color: transparent;
 	-webkit-tap-highlight-color: transparent;
+	user-select: text;
+	-webkit-user-select: text;
 }
 
 optgroup, option {
@@ -184,6 +191,16 @@ rt {
 	padding: 0.3em 0.5em;
 }
 
+._selectable {
+	user-select: text;
+	-webkit-user-select: text;
+}
+
+._selectableAtomic {
+	user-select: all;
+	-webkit-user-select: all;
+}
+
 ._noSelect {
 	user-select: none;
 	-webkit-user-select: none;