diff --git a/band-plan.html b/band-plan.html
index fe64d6c..7c9e358 100644
--- a/band-plan.html
+++ b/band-plan.html
@@ -39,7 +39,7 @@ div>label {
 
 		function create_element_link(element, href) {
 			element.addEventListener("click", () => {
-				var lnk = document.createElement('a');
+				let lnk = document.createElement('a');
 
 				if (typeof href === "function") {
 					lnk.href = href();
@@ -127,9 +127,9 @@ div>label {
 		}
 
 		function update_table(bases, extensions) {
-			var tdata = [];
-			var base_header = {};
-			var ext_header = {};
+			let tdata = [];
+			let base_header = {};
+			let ext_header = {};
 
 			// first, fill base_header
 			bases.forEach((base) => {
@@ -208,7 +208,7 @@ div>label {
 
 			// require in tabular-tables
 			// eslint-disable-next-line no-undef
-			var table = new Tabulator("#data-table", {
+			let table = new Tabulator("#data-table", {
 				layout: "fitDataTable",
 				initialSort: [
 					{column: "frequency", dir: "asc"},
@@ -257,7 +257,7 @@ div>label {
 			});
 
 			table.on("tableBuilt", () => {
-				var div_togglebuttons = document.getElementById("togglebuttons");
+				let div_togglebuttons = document.getElementById("togglebuttons");
 				div_togglebuttons.innerHTML = "<span>Toggle column:</span>";
 				table.getColumns().forEach((col) => {
 					let col_name = col.getField();