implemented one-way switching of php via javascript.

music/js/switch.js

@@ -0,0 +1,10 @@
+async function modeSwitch() {
+  const content = document.getElementById("content");
+  var response = await fetch('explore.php');
+
+  if (response.status === 200) {
+    let data = async () => { return await response.text() };
+    let text = await data();
+    content.innerHTML = text;
+  }
+}