refactoring with ciclo for

assets/scss/libs/main.scss

@@ -235,11 +235,20 @@ ul.item-list li {
     line-height: 20px;
 }
 
-.m-25 {
-    margin: 25px;
-}
-.mx-25 {
-    margin: 25px 0;
+@each $value in (10, 20, 25) {
+    $margin_sizes: ("": "#{$value}px", "y": "#{$value}px 0", "x": "0 #{$value}px");
+    @each $name, $margin in $margin_sizes {
+      .m#{$name}-#{$value} {
+        margin: #{$margin} !important;
+      }
+    }
+
+    $margin_sizes: ("t": "top", "e": "right", "b": "bottom", "s": "left");
+    @each $name, $position in $margin_sizes {
+      .m#{$name}-#{$value} {
+        margin-#{$position}: #{$value}px !important;
+      }
+    }
 }
 .my-25 {
     margin: 0 25px;