diff --git a/src/runtime/components/Button.vue b/src/runtime/components/Button.vue
index fbec6fb6..28972ae2 100644
--- a/src/runtime/components/Button.vue
+++ b/src/runtime/components/Button.vue
@@ -90,7 +90,7 @@ const ui = computed(() => button({
   <ULink
     :type="type"
     :disabled="disabled || isLoading"
-    :class="ui.base({ class: props.class })"
+    :class="ui.base({ class: [props.class, props.ui?.base] })"
     v-bind="linkProps"
     raw
     @click="onClickWrapper"
diff --git a/src/runtime/components/Select.vue b/src/runtime/components/Select.vue
index 2d4ba771..645b7df5 100644
--- a/src/runtime/components/Select.vue
+++ b/src/runtime/components/Select.vue
@@ -161,7 +161,7 @@ function onUpdateOpen(value: boolean) {
     @update:model-value="onUpdate"
     @update:open="onUpdateOpen"
   >
-    <SelectTrigger :class="ui.base({ class: props.class })">
+    <SelectTrigger :class="ui.base({ class: [props.class, props.ui?.base] })">
       <span v-if="isLeading || !!slots.leading" :class="ui.leading({ class: props.ui?.leading })">
         <slot name="leading" :model-value="modelValue" :open="open" :ui="ui">
           <UIcon v-if="leadingIconName" :name="leadingIconName" :class="ui.leadingIcon({ class: props.ui?.leadingIcon })" />
diff --git a/src/runtime/components/SelectMenu.vue b/src/runtime/components/SelectMenu.vue
index 6f36b514..a7ba852a 100644
--- a/src/runtime/components/SelectMenu.vue
+++ b/src/runtime/components/SelectMenu.vue
@@ -219,7 +219,7 @@ function onUpdateOpen(value: boolean) {
     @update:open="onUpdateOpen"
   >
     <ComboboxAnchor as-child>
-      <ComboboxTrigger :class="ui.base({ class: props.class })" tabindex="0">
+      <ComboboxTrigger :class="ui.base({ class: [props.class, props.ui?.base] })" tabindex="0">
         <span v-if="isLeading || !!slots.leading" :class="ui.leading({ class: props.ui?.leading })">
           <slot name="leading" :model-value="(modelValue as T)" :open="open" :ui="ui">
             <UIcon v-if="leadingIconName" :name="leadingIconName" :class="ui.leadingIcon({ class: props.ui?.leadingIcon })" />
diff --git a/src/runtime/components/Toaster.vue b/src/runtime/components/Toaster.vue
index d4214b35..601cc8ca 100644
--- a/src/runtime/components/Toaster.vue
+++ b/src/runtime/components/Toaster.vue
@@ -115,7 +115,7 @@ function getOffset(index: number) {
 
     <ToastViewport
       :data-expanded="expanded"
-      :class="ui.viewport({ class: props.class })"
+      :class="ui.viewport({ class: [props.class, props.ui?.viewport] })"
       :style="{
         '--scale-factor': '0.05',
         '--translate-factor': position?.startsWith('top') ? '1px' : '-1px',