docs(components): [tree] update example style (#19945)

docs/examples/tree/checking-tree.vue

@@ -10,7 +10,7 @@
     :props="defaultProps"
   />
 
-  <div class="buttons">
+  <div class="mt-2">
     <el-button @click="getCheckedNodes">get by node</el-button>
     <el-button @click="getCheckedKeys">get by key</el-button>
     <el-button @click="setCheckedNodes">set by node</el-button>

docs/examples/tree/custom-node-class.vue

@@ -84,12 +84,15 @@ const data: Tree[] = [
 .is-penultimate > .el-tree-node__content {
   color: #626aef;
 }
-
-.el-tree .el-tree-node.is-penultimate > .el-tree-node__children {
-  display: flex;
-  flex-direction: row;
-}
 .is-penultimate > .el-tree-node__children > div {
-  width: 25%;
+  display: inline-block;
+  margin-right: 4px;
+
+  &:not(:first-child) .el-tree-node__content {
+    padding-left: 0px !important;
+  }
+  .el-tree-node__content {
+    padding-right: 16px;
+  }
 }
 </style>

docs/examples/tree/filtering.vue

@@ -1,7 +1,7 @@
 <template>
   <el-input
     v-model="filterText"
-    style="width: 240px"
+    class="w-60 mb-2"
     placeholder="Filter keyword"
   />