diff --git a/index.html b/index.html
index d7cba96..9f4bc4d 100644
--- a/index.html
+++ b/index.html
@@ -8,12 +8,14 @@
   </head>
   <body>
 		<div id="calculator">
-			<label for="expr">Expression</label>
-			<input id="expr" required type="text" />
+			<div id="input-row">
+				<label for="expr">Expression</label>
+				<input id="expr" required type="text" />
 
-			<div id="modulus-row">
-				<label for="modulus">mod</label>
-				<input id="modulus" required type="number" min="1" step="1" />
+				<div id="modulus-box">
+					<label id="modulus-label" for="modulus">mod</label>
+					<input id="modulus" required type="number" min="1" step="1" />
+				</div>
 			</div>
 
 			<output id="result" for="expr modulus"></output>
diff --git a/styles.css b/styles.css
index cf745f0..c577966 100644
--- a/styles.css
+++ b/styles.css
@@ -7,13 +7,32 @@ label[for="expr"] {
 	display: none;
 }
 
-#expr {
+#input-row {
 	grid-column: 1 / 5;
+	display: flex;
+	flex-flow: wrap;
 }
 
-#modulus-row {
-	grid-column: 1 / 5;
-	text-align: right;
+#expr {
+	flex: 4 auto;
+	min-width: 0;
+}
+
+#modulus-box {
+	flex: auto;
+	display: flex;
+	flex-flow: wrap;
+	justify-content: end;
+	min-width: 0;
+}
+
+#modulus-label {
+	flex: initial;
+}
+
+#modulus {
+	flex: auto;
+	min-width: 0;
 }
 
 #result {
