Rough implementation of appearance settings

framework/core/less/admin/AppearancePage.less

@@ -0,0 +1,34 @@
+.AppearancePage {
+  @media @desktop-up {
+    .container {
+      max-width: 600px;
+      padding: 30px;
+      margin: 0;
+    }
+  }
+
+  fieldset {
+    margin-bottom: 40px;
+  }
+}
+.AppearancePage-colors-input {
+  overflow: hidden;
+
+  input {
+    width: 49%;
+    float: left;
+
+    &:first-child {
+      margin-right: 2%;
+    }
+  }
+}
+.AppearancePage-colors-input,
+.AppearancePage-colors .Checkbox {
+  margin-bottom: 15px;
+}
+
+.EditCustomCssModal textarea {
+  font-family: monospace;
+  line-height: 1;
+}

framework/core/less/admin/app.less

@@ -6,3 +6,4 @@
 @import "PermissionsPage.less";
 @import "EditGroupModal.less";
 @import "ExtensionsPage.less";
+@import "AppearancePage.less";