fix: box-sizing border-box by default

src/styles.scss

@@ -7,6 +7,11 @@
   --secondaryFont: 'Poppins', sans-serif;
 }
 
+html,
+* {
+  box-sizing: border-box;
+}
+
 body {
   background-color: var(--primary);
   font-family: var(--primaryFont);