Problem with Image instead of text tab

.open_action {
	position: fixed;
    background-image: url("images/TabSlide.png");
    background-repeat: no-repeat;
    background-size: 48px 297px;
	width:48px;
    height: 297px;
    top: 45% !important;
}
.closed_action {
	position: static;
    background-image: url("images/TabSlide.png");
    background-repeat: no-repeat;
    background-size: 48px 297px;
	width:48px;
    height: 297px;
    top: 45% !important;
}

(Where TabSlide.png is the picture that I have replaced)
all the rest is in default condition.

How can I fix this problem?