Use basic styling from sample html

src/index.css

@@ -1,5 +1,17 @@
-body {
+*,*::before,*::after {
+  box-sizing: border-box;
+}
+
+* {
   margin: 0;
   padding: 0;
+}
+
+html, body, #root {
+  width: 100%;
+  height: 100%;
+}
+
+body {
   font-family: sans-serif;
 }