index.css

*{
    box-sizing: border-box;
}

h1 {
    font-family: Brushstroke, fantasy;
    color: #000000;
}

body {
    
    background-color: rgb(12,34,67);

}

p {
    padding: 10px;
    margin: 0;
}

.container {
    border: none;
    margin-left: auto;
    margin-right: auto;
    margin-top: 10px;
    margin-bottom: 10px;
    padding: 10px;
    border-radius: 0px;
}

section {
    border: 1px solid black;
    background-color:rgb(235,235,235);
    width: 100%;
    height: auto;
    font-family: Helvetica;
    color: black;
    position: relative;
    overflow: auto;
}

#pizza {
    border: 1px solid black;
    text-align: center;
    width: 30%;
    margin-left: 70%;
    font-family: Georgia,sans-serif;
    font-weight: bold;
    font-size: 125%;
    margin-bottom: 0;
    margin-top: 0;
    padding: 5px;
    background-color: rgb(45,21,45);
    color: #FFFF00;
}

#chicken {
    border: 1px solid black;
    text-align: center;
    width: 30%;
    margin-left: 70%;
    font-family: Georgia,sans-serif;
    font-weight: bold;
    font-size: 125%;
    margin-bottom: 0;
    margin-top: 0;
    padding: 5px;
    background-color: rgb(32,144,84);
    color: #FFFF00;
}

#hamburger {
    border: 1px solid black;
    text-align: center;
    width: 30%;
    margin-left: 70%;
    font-family: Georgia,sans-serif;
    font-weight: bold;
    font-size: 125%;
    margin-bottom: 0;
    margin-top: 0;
    background-color: rgb(12,1,2);
    color: #FFFF00;
    padding: 5px;
}

#pizza-div {
  margin-bottom: 10px;
  margin-top: 10px;
}

#chicken-div {
  margin-bottom: 10px;
  margin-top: 10px;
}

#hamburger-div {
  margin-bottom: 10px;
  margin-top: 10px;
}

.navbar-brand {
  font-size: 2em;
  border: 0 0 10px 10px;
  color: #FFFFFF;
}

#header-nav {
  border: 0;
  background-color: rgb(123,45,67);
  color: #FFFFFF;
  border-radius:0;
}

.navbar-header button.navbar-toggle, .navbar-header .icon-bar {
  border: 1px solid green;
}
.navbar-header button.navbar-toggle {
  clear: both;
  margin-top: -30px;
}

.nav-header {
  background-color: #FFFFFF;
}

.nav-brand {
  color: #FFFFFF;
  font-size: 1.5em;
}

#nav-list {
  color: white;
}

hr {
  border-color: white;
}

.item {
  color: white;
  font-size: 1.2em;
}

/*desktop version*/
@media (min-width: 992px){
    .column-lg-4 {
        float: left;
        width: 33.33%;
    }
}
/*tablet version*/
@media (min-width: 768px) and (max-width: 991px){
    .colmn-md-6 {
        float: left;
        width: 50%;
    }
    .colmn-md-12 {
        float: left;
        width: 100%;
    }
}
/*mobile version*/
@media (max-width: 767px){
    .colmn-sm-12 {
        float: left;
        width: 100%;
    }
}