**For Magento 2:**

If you want to style or customize in success page after order success page redirect to cart page.

Now solution is here:

Go To `vendor/magento/module-checkout/Controller/Onepage`
 open `Success.php` File.

In this file you see Below Code 

     if (!$this->_objectManager->get('Magento\Checkout\Model\Session\SuccessValidator')->isValid()) {
         return $this->resultRedirectFactory->create()->setPath('checkout/cart');
     }

Just comment this code and your problem is solve. After comment this you dont redirect to cart page.