docs: 避免文档搜索框被主题样式影响 Closes #6389 (#6819)

examples/components/DocSearch.jsx

@@ -164,7 +164,7 @@ export default class DocSearch extends React.Component {
           show={this.state.show}
           position={'right'}
         >
-          <div className={`${this.props.theme.ns}TextControl-input search-bar`}>
+          <div className={`search-bar`}>
             <Icon icon="search" className="icon" />
             <input
               ref={this.ref}

examples/style.scss

@@ -949,16 +949,23 @@ body {
 
   .search-bar {
     padding: 22px 20px;
-    border: 0;
     border-bottom: 1px solid #e8ebee;
     border-radius: 0;
     font-size: 16px;
     font-weight: 500;
+    display: flex;
 
     > .icon-search {
       margin-right: 10px;
       top: 1px;
     }
+    > input {
+      flex-basis: 1.875rem;
+      flex-grow: 1;
+      border: none;
+      outline: none;
+      width: 100%;
+    }
   }
 
   .search-result {