ant-design/components/collapse/demo/custom.tsx

import React from 'react';
import { CaretRightOutlined } from '@ant-design/icons';
import { Collapse, theme } from 'antd';

const { Panel } = Collapse;

const text = `
  A dog is a type of domesticated animal.
  Known for its loyalty and faithfulness,
  it can be found as a welcome guest in many households across the world.
`;

const App: React.FC = () => {
  const { token } = theme.useToken();

  const panelStyle = {
    marginBottom: 24,
    background: token.colorFillAlter,
    borderRadius: token.borderRadiusLG,
    border: 'none',
  };

  return (
    <Collapse
      bordered={false}
      defaultActiveKey={['1']}
      expandIcon={({ isActive }) => <CaretRightOutlined rotate={isActive ? 90 : 0} />}
      style={{ background: token.colorBgContainer }}
    >
      <Panel header="This is panel header 1" key="1" style={panelStyle}>
        <p>{text}</p>
      </Panel>
      <Panel header="This is panel header 2" key="2" style={panelStyle}>
        <p>{text}</p>
      </Panel>
      <Panel header="This is panel header 3" key="3" style={panelStyle}>
        <p>{text}</p>
      </Panel>
    </Collapse>
  );
};

export default App;