How to Change the Search and Register Form Colors

Please check each code and choose the ones you want to use, then add the codes to style.css of child theme

General code:

.form-header {
    border-left: 10px solid rgba(31, 168, 209, 0.3);
    border-right: 10px solid rgba(31, 168, 209, 0.3);
    border-top: 10px solid rgba(31, 168, 209, 0.3);
}
.form-search, .form-header {
    background: none repeat scroll 0 0 #0296C0;
}
.form-search {
    border-left: 10px solid rgba(31, 168, 209, 0.3);
    border-right: 10px solid rgba(31, 168, 209, 0.3);
}

.form-search.custom div.custom.dropdown a.selector, .form-search.custom div.custom.dropdown a.current, .form-search.custom select {
    border: 1px solid #1FA8D1;
}
.form-search.custom div.custom.dropdown a.current, .form-search.custom input[type="text"], .form-search.custom input[type="password"], .form-search.custom select {
    background-color: #1FA8D1;
}

Witch Latest Carousel:

.form-footer {
    background: url("../images/patterns/gray_pattern.gif") repeat scroll 0 0 #F8F8F8 !important;
    border-bottom: 10px solid #FAFAFA !important;
    border-left: 10px solid #FAFAFA !important;
    border-right: 10px solid #FAFAFA !important;
    color: #777777 !important;
}

Without Latest Carousel:

.form-footer {
    background: none !important;
    border-bottom: none !important;
    border-left: none !important;
    border-right: none !important;
    color: #777777 !important;
}

How to change the colors

You can use normal color names like black, blue, red etc

Or specific color codes like #1FA8D1

Check a list of colors and tools to get the colors you want

http://html-color-codes.info/codigos-de-colores-hexadecimales/

http://www.w3schools.com/colors/colors_picker.asp