Hello Alex,

try

.portfolio .item:first-child .item-title::after {
    color: #FF1B0B;
}

change the hex color and add the code to customizer -> additional CSS

Contact page:

if it's about this message

https://prnt.sc/1s0yux0

you have

.wpcf7 form.sent .wpcf7-response-output {
    border-color: #46b450;
}
.wpcf7 form .wpcf7-response-output {
    border: 2px solid #00a0d2;
}

div.wpcf7-response-output {
    background: #ff0000;
    color: #fff;
}