textswitch: Fill the width of the host element

src/textswitch.js

@@ -49,6 +49,7 @@ export class TextSwitch extends LitElement {
 
             div {
                 white-space: nowrap;
+                display: flex;
             }
 
             #button1 {
@@ -60,6 +61,10 @@ export class TextSwitch extends LitElement {
                 color: var(--vpu-primary-text-color) !important;
             }
 
+            .button {
+                flex-grow: 1;
+            }
+
             .button:hover {
                 background-color: var(--vpu-secondary-bg-color) !important;
             }