split formatter page to textarea and editor

src/routes/(editor)/experimental/editor.module.css

@@ -0,0 +1,50 @@
+.root {
+    position: relative;
+    margin: 1em;
+    padding: .5em;
+    gap: 1em;
+    display: grid;
+
+    grid: 100% / repeat(2, minmax(0, 1fr));
+
+    inline-size: calc(100% - 2em);
+    block-size: calc(100% - 2em);
+
+    place-content: start;
+    background-color: var(--surface-500);
+    border-radius: var(--radii-xl);
+
+    & > :is(textarea, .textarea) {
+        overflow: auto;
+        padding: .5em;
+        background-color: transparent;
+    }
+
+    & ::highlight(search-results) {
+        background-color: var(--secondary-900);
+    }
+
+    & ::highlight(spelling-error) {
+        text-decoration-line: spelling-error;
+    }
+
+    & ::highlight(grammar-error) {
+        text-decoration-line: grammar-error;
+    }
+
+    .search {
+        position: absolute;
+        inset-inline-end: 0;
+        inset-block-start: 0;
+
+        display: block grid;
+        grid-auto-flow: row;
+
+        padding: .5em;
+        gap: .5em;
+
+        background-color: var(--surface-700);
+        border-radius: var(--radii-m);
+        box-shadow: var(--shadow-2);
+    }
+}