Error when applying custom css rules

Hi there,
I'm trying to turn all my buttons and input and text area's border-radius to be rounded, so I had used this css snippet:

input,
select, 
textarea,
.wp-block-button .wp-block-button__link, 
a.button, 
a.button:visited, 
button, 
html input[type=button], 
input[type=reset], 
input[type=submit],
.woocommerce #respond input#submit, 
.woocommerce a.button, 
.woocommerce button.button, 
.woocommerce input.button {
    border-radius: 5px;
}

but wordpress customizer gives me this error: "Looks like something’s gone wrong. Wait a couple seconds, and then try again."
Also I tried to do it using "simple CSS" plugin but also gives me an error: "Not Acceptable!
An appropriate representation of the requested resource could not be found on this server. This error was generated by Mod_Security."

Any help will be appreciated.

Thanks in advanced.