// Create array to store tab images
var tabImages = new Array(6);

// Preload images into tabImages array
tabImages[0] = new Image();
tabImages[0].src = "images/shop_tab_off.jpg";
tabImages[1] = new Image();
tabImages[1].src = "images/shop_tab_on.jpg";
tabImages[2] = new Image();
tabImages[2].src = "images/location_tab_off.jpg";
tabImages[3] = new Image();
tabImages[3].src = "images/location_tab_on.jpg";
tabImages[4] = new Image();
tabImages[4].src = "images/herstory_tab_off.jpg";
tabImages[5] = new Image();
tabImages[5].src = "images/herstory_tab_on.jpg";

function SwapTabImage(tid, ind) {
  document[tid].src = tabImages[ind].src;
}