Collapse the logout button text on narrow displays

This prevents ugly line wraps on long site names

snikket_web/scss/app.scss

@@ -1017,6 +1017,23 @@ div.profile-card {
 			display: none;
 		}
 	}
+
+
+	input[type="submit"], button, .button {
+		&.slimmify {
+			> svg.icon {
+				margin-right: 0;
+			}
+
+			> span {
+				position: absolute;
+				width: 1px;
+				height: 1px;
+				overflow: hidden;
+				top: -100px;
+			}
+		}
+	}
 }
 
 /* clipboard button */

snikket_web/templates/app.html

@@ -5,5 +5,5 @@
 {% endblock %}
 {% block topbar_right %}
 {{- super() -}}
-{% call standard_button("logout", url_for("user.logout"), class="tertiary") %}{% trans %}Log out{% endtrans %}{% endcall %}
+{% call standard_button("logout", url_for("user.logout"), class="tertiary slimmify") %}{% trans %}Log out{% endtrans %}{% endcall %}
 {%- endblock %}