A blockquote is an element which defines a block quotation within the text. They should essentially be used to show the quotations of another person which is related to your post content. Generally they are used to signify important text by drawing the viewer's eye to a separate block of text.
In the standard (Minima) blogger template a blockquote is defined by the following CSS code :
To make it look better modify the above code as below :
You can change the border color by changing this line :border:2px #000000 solid;
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