Split one CSS file into multiple or extract contents after a certain comment

Question

How can I split a CSS file into two by a custom condition, that means is there a way to split one CSV file after certain comments in the CSS file?

.one{
background-color: black;
}

.two{
background-color: yellow;
}

/** end of css1 **/

.three{
background-color: red;
}

.four{
background-color: green;
}

now I'd like to copy only contents after the comment

/** end of css1 **/

one new file should have only

.three{
background-color: red;
}

.four{
background-color: green;
}