fix(button): line-height & wave

src/_base/index.ts

@@ -6,6 +6,7 @@ export { default as NBaseFocusDetector } from './focus-detector'
 export { default as NBaseLoading } from './loading'
 export { default as NBaseSelectMenu } from './select-menu'
 export { default as NBaseWave } from './wave'
+export type { BaseWaveRef } from './wave'
 export { default as NBaseMenuMask } from './menu-mask'
 export { default as NBaseSelection } from './selection'
 export { default as NBaseSlotMachine } from './slot-machine'

src/_base/wave/index.ts

@@ -1 +1,2 @@
 export { default } from './src/Wave'
+export type { BaseWaveRef } from './src/Wave'

src/_base/wave/src/Wave.tsx

@@ -2,6 +2,10 @@ import { h, defineComponent, ref, onBeforeUnmount, nextTick } from 'vue'
 import { useStyle } from '../../../_mixins'
 import style from './styles/index.cssr'
 
+export interface BaseWaveRef {
+  play: () => void
+}
+
 export default defineComponent({
   name: 'BaseWave',
   setup () {

src/button/src/styles/button.cssr.ts

@@ -35,6 +35,7 @@ import iconSwitchTransition from '../../../_styles/transitions/icon-switch'
 // --border-color-xxx, used for custom color
 export default c([
   cB('button', `
+    line-height: 1;
     font-family: inherit;
     padding: var(--padding);
     height: var(--height);
@@ -188,7 +189,7 @@ export default c([
         left: 0;
         top: 50%;
         transform: translateY(-50%);
-        display: block;
+        display: flex;
       `, [
         iconSwitchTransition({
           top: '50%',