feat: forms disabled styles

Author: olivier3lanc

docs/assets/css/dsg_forms.css

@@ -12,6 +12,11 @@ input[type="search"]:focus {
     outline: none;
     border-color: var(--dsg-colors-secondary-500);
 }
+input[type="text"]:disabled,
+input[type="search"]:disabled,
+button:disabled {
+    opacity: 0.5;
+}
 
 /* Checkboxes UI */
 .__checkbox_ui:checked ~ label .__checkbox_ui {