CSS issues with changing colors

Hello,

I’m trying to change the color of my websites underlines, links, buttons, and hover overs to purple/black. I’ve been using codes from other forum posts on here with some success, but for some reason the coding works on one page and will not work on another page; sometimes the coding works and sometimes it doesn’t.

I’ve put the coding in the additional css tab as well as the editor page on the dashboard. I’m not sure if they’re conflicting, or there is something i’m missing, but the coding works one minute than goes back to the original colors the next minute.

This is the coding I have in my additional CSS as well as my editor on the dashboard:
/*
You can add your own CSS here.

Click the help icon above to learn more.
*/

a {
color: #5A4BA3;
}
a:hover {
color: #2A2D33;
}
.widget .widget-title:before,
.nav-links a {
background-color: #5A4BA3;
}
#main-nav a:hover {
color: #5A4BA3;
}

.entry-title a:after {
height: 2px;
background: #5A4BA3 !important;
width: 50px;
}

.listpost-content-wrap .entry-title a:after {
background: #5A4BA3 !important;
}

ul.nav > li.current_page_item > a:before {
height: 2px;
background: #5A4BA3 !important;
}

.entry-title:before {
height: 3px;
background: #5A4BA3 !important;
}

If anyone has ideas on what the issue/issues are and could assist i’d greatly appreciate it.

Thanks in advance!