Hi Guys you can change the blue "wavy background" by going into the home.css file and then editing the section which is store message: Code should be something similar like this and this is what i have done to mine:
#storeMessage {
background-image: url("");
background-repeat: no-repeat;
height: 260px;
margin-left: 1px;
overflow:hidden;
background-color: #06245c;
margin-right: 1px;
}
hope it helps!!!