.btn.book.custom {
   visibility: hidden;
   position: relative;
   display: inline-block;
}

.btn.book.custom::before {
   content: "Резервирай сега"; /* Or your preferred text */
   visibility: visible;
   position: absolute;
   top: 0;
   left: 0;
   width: 120%;
   height: 110%;
   display: flex;
   align-items: center;
   justify-content: center;
   background: inherit;  
   border-radius: 5px;             
}

/*
	Custom CSS
	Please make sure your CSS rules are 
	more particular / have higher priority
	then other page styles
*/
 #events h3   {
	/* add your css rule here */
}


 #events p.duration, #events div.duration   {
	/* add your css rule here */
}


 #events p.description, #events div.description   {
	/* add your css rule here */
}


 #events .selectedEvent   {
	/* add your css rule here */
}


 #events input.reserve_time_btn   {
	/* add your css rule here */
}


 #events input.select_another_btn   {
	/* add your css rule here */
}


 #eventForm #start_date-block-container h3, #eventForm #timeline-container h3   {
	/* add your css rule here */
}


 #eventForm #save_button   {
	/* add your css rule here */
}


 div.ui-widget-content   {
	/* add your css rule here */
}


 div.ui-widget-header   {
	/* add your css rule here */
}


 #timeline-container table.timeline   {
	/* add your css rule here */
}


 .timeline td.not_worked_time   {
	/* add your css rule here */
}


 .timeline td.free_time   {
	/* add your css rule here */
}


 .timeline td.selected_time   {
	/* add your css rule here */
}


 .timeline td.reserved_time   {
	/* add your css rule here */
}


 div#loading   {
	/* add your css rule here */
}


 #start_date-block-container .zend_form dt, start_date-block-container .zend_form dt b, start_date-block-container .zend_form dd label   {
	/* add your css rule here */
}