diff --git a/src/sass/blocks/layout/_app.scss b/src/sass/blocks/layout/_app.scss
index 7fe3c3e..a90ed24 100644
--- a/src/sass/blocks/layout/_app.scss
+++ b/src/sass/blocks/layout/_app.scss
@@ -28,7 +28,7 @@
             display: none;
         }
 
-        @include respond-to(not-lg) {
+        @include respond-to(smaller-lg) {
             transform: translateX(-100%);
         }
         @include respond-to(lg) {
@@ -45,7 +45,7 @@
         right: 0;
         bottom: 0;
 
-        @include respond-to(not-lg) {
+        @include respond-to(smaller-lg) {
             &:after {
                 display: block;
                 content: '';
@@ -87,7 +87,7 @@
     }
 
     // Animation
-    @include respond-to(not-lg) {
+    @include respond-to(smaller-lg) {
         will-change: transform;
         transform-style: preserve-3d;
         transition: transform 0.15s ease-out;
@@ -99,7 +99,7 @@
 
     // Modifier to open sidebar
     &--show-aside {
-        @include respond-to(not-lg) {
+        @include respond-to(smaller-lg) {
             transform: translateX($aside-width);
             .app__container:after {
                 transform: none;
diff --git a/src/sass/blocks/layout/_mail-list-wrapper.scss b/src/sass/blocks/layout/_mail-list-wrapper.scss
index 4d9a8ba..abb2cc5 100644
--- a/src/sass/blocks/layout/_mail-list-wrapper.scss
+++ b/src/sass/blocks/layout/_mail-list-wrapper.scss
@@ -35,7 +35,15 @@
 
     // Modifier to open sidebar
     &--show-aside {
-        @include respond-to(not-md) {
+        @include respond-to(smaller-md) {
+            .mail-list-wrapper__aside {
+                display: block;
+            }
+            .mail-list-wrapper__container {
+                display: none;
+            }
+        }
+        @include respond-to(lg) {
             .mail-list-wrapper__aside {
                 display: block;
             }
diff --git a/src/sass/blocks/views/_mail-list.scss b/src/sass/blocks/views/_mail-list.scss
index 46e7586..fe0e63e 100755
--- a/src/sass/blocks/views/_mail-list.scss
+++ b/src/sass/blocks/views/_mail-list.scss
@@ -7,7 +7,7 @@
     // do not share any common styles between large and other screens
     // because styling is very different
 
-    @include respond-to(not-lg) {
+    @include respond-to(smaller-lg) {
         display: flex;
         flex-direction: column;
         height: 100%;
@@ -152,7 +152,7 @@
     // do not share any common styles between large and other screens
     // because styling is very different
 
-    @include respond-to(not-lg) {
+    @include respond-to(smaller-lg) {
         $padding-horizontal: 30px;
         $padding-vertical: 11px;
 
diff --git a/src/sass/blocks/views/_read.scss b/src/sass/blocks/views/_read.scss
index 62f82cc..4a5eb9d 100644
--- a/src/sass/blocks/views/_read.scss
+++ b/src/sass/blocks/views/_read.scss
@@ -161,7 +161,7 @@
             }
         }
     }
-    @include respond-to(sm-only) {
+    @include respond-to(smaller-md) {
         &--stripped {
             .read__addresses > * {
                 display: none;
diff --git a/src/sass/mixins/_responsive.scss b/src/sass/mixins/_responsive.scss
index 9e6c0fc..b1f2955 100755
--- a/src/sass/mixins/_responsive.scss
+++ b/src/sass/mixins/_responsive.scss
@@ -7,8 +7,8 @@ $mediaqueries: (
     md:                  "(min-width: #{$screen-md-min})",
     md-only:             "(min-width: #{$screen-md-min}) and (max-width: #{$screen-md-max})",
     lg:                  "(min-width: #{$screen-lg-min})",
-    not-md:              "(max-width: #{$screen-sm-max}), (min-width: #{$screen-lg-min})",
-    not-lg:              "(max-width: #{$screen-md-max})"
+    smaller-md:          "(max-width: #{$screen-sm-max})",
+    smaller-lg:          "(max-width: #{$screen-md-max})",
 );
 
 // Central Media Query Mixin
diff --git a/src/sass/utilities/_responsive.scss b/src/sass/utilities/_responsive.scss
index 974dfbd..b181fc7 100644
--- a/src/sass/utilities/_responsive.scss
+++ b/src/sass/utilities/_responsive.scss
@@ -6,7 +6,7 @@
     }
 }
 .u-visible-md {
-    @include respond-to(sm-only) {
+    @include respond-to(smaller-md) {
         display: none !important;
     }
     @include respond-to(lg) {
@@ -14,13 +14,13 @@
     }
 }
 .u-visible-lg {
-    @include respond-to(not-lg) {
+    @include respond-to(smaller-lg) {
         display: none !important;
     }
 }
 
 .u-hidden-sm {
-    @include respond-to(sm-only) {
+    @include respond-to(smaller-md) {
         display: none !important;
     }
 }