Fix RTL handling, holiday names direction and UI details for full page RTL.

src/components/HeaderControls.vue

@@ -101,12 +101,12 @@ onBeforeUnmount(() => {
   display: flex;
   justify-content: end;
   align-items: center;
-  margin-right: 1.5rem;
+  margin-inline-end: 2rem;
 }
 .toggle-btn {
   position: fixed;
   top: 0;
-  right: 0;
+  inset-inline-end: 0;
   background: transparent;
   border: none;
   color: var(--muted);
@@ -157,7 +157,6 @@ onBeforeUnmount(() => {
   color: var(--muted);
   padding: 0;
   margin: 0;
-  margin-right: 0.6rem;
   cursor: pointer;
   font-size: 1.5rem;
   line-height: 1;