Most of the items in EyeCare WordPress theme provide you options to change colors through WordPress cutomizer also you can play with colors in Page builder modules. However that is time consuming so the quick way to change colors is changing colors for optometry WordPress theme directly through CSS. As theme's CSS file keep updating with theme's new updates. And we are not going to make our secondary color as yours. So the best way is put your CSS in wp-admin >> Appearance >> customize >> additional CSS go there and add the following CSS make sure to change color code as per your desired color code.
/*Property Background Color*/
.topBar,
#top,
.blog-post.sticky,
.blog-post .sticky-post,
.post-content .category-block a,
.call-to-action,
.tags li a:hover,
.special-staff .doctor-links,
.dots-style .owl-dot.active span,
.dots-style .owl-dot:hover span,
.top-bar .dropdown.menu>li.opens-right>.is-dropdown-submenu li a,
.layer3,
.is-active a,
.top-bar ul li a:hover,
.owl-nav .owl-prev:hover,
.owl-nav .owl-next:hover,
.icon-box .icon-side,
.button.secondary,
.bordered-light:hover,
.button.primary:hover,
.woocommerce .button-big .button,
.product-img .sale,
.product-page .sale {
background-color:#56b224 !important;
}
/*Property Border Color*/
.dots-style .owl-dot span,
.button.bordered-dark,
.header .icon-box .icon-side,
.owl-nav .owl-prev, .owl-nav .owl-next,
.bordered-light:hover {
border-color:#56b224 !important;
}
/*Property Color*/
.process .number,
.row .our-process h2,
.price span,
.footer-icon-box .icon-side,
.footer a:hover,
.footer h2,
.welcome-message h2 span,
.single-doctor-page .hentry h2 span,
.slider-form-wrapper .title-area p,
.button.bordered-dark,
.header .icon-box .icon-side,
.section-title h2 span,
.owl-nav .owl-prev,
.owl-nav .owl-next,
.entry-content a {
color:#56b224 !important;
}
/*Devices below 40 EM*/
@media only screen and (max-width: 40em) {
.top-bar ul ul {
background-color:#56b224 !important;
}
}
/*Devices between 64em and 40em*/
@media screen and (min-width: 40em) and (max-width: 64em) {
.top-bar ul ul {
background-color:#56b224 !important;
}
}
Please copy and add the CSS above in your wp-admin >> Appearance >> Customize >> Additional CSS and that will do the work for you let me know if you have any further questions. Thanks