Navigation menu is too big on smaller resolution

As seen in the attached images one screen (smaller) creates three row stacked navigation menu but on the larger resolution it's perfect. What can I do to fix this so it's consistent throughout larger and smaller displays?

This is my code for my navigation:

@media only screen and (min-width: 640px) and (max-width: 1500px) { 
  a{
    width:80%; 
    margin:auto}
}

.header-nav-folder-title {
  height: 30px;
}

.header-nav-item {
  padding: 12px 16px;
}

* {
  box-sizing: border-box;
}

.header-nav-item--active a{
  background: unset !important;
}

.header-nav-item--hover a{
  background: unset !important;
}

a.header-nav-folder-title:hover + div, .header-nav-folder-content {
    text-align: center !important;
    position: absolute;
    left: 50% !important;
    right: unset !important;
    -webkit-transform: translatex(-50%);
    -o-transform: translatex(-50%);
    transform: translatex(-50%);
  background: #fff !important;
      position: absolute;
      padding-left: 155px;
      margin-top: 10px;
}

.header-nav-item {
  margin: 0;
  padding: 0;
  list-style: none;
  overflow: hidden;
}



//STYLING AROUND DROPDOWN
.header-nav-folder-content {
  padding-top: 5px !important;
      padding: 2px 10px;
    border: 1px solid #979997;

    -webkit-appearance: none;
    -moz-appearance: none;
    -ms-appearance: none;
    -o-appearance: none;
    appearance: none;

    -webkit-border-radius: 4px;
    -moz-border-radius: 4px;
    -ms-border-radius: 4px;
    -o-border-radius: 4px;
    border-radius: 4px;
  }

.header-nav-item:hover{
  overflow: visible;
  
}

.header-nav-folder-item-content {
  position: relative;
  background-color: #fff;  
}

.header-nav-folder-item-content:hover {
  color:#AFAFAF !important;
}


.header-nav-folder-item-content {
  display: block;
  padding: 7px 6px;
  color: black;
  text-decoration: none;
  text-align: center;
}



// END OF NAVIGATION STYLING

You can consider forcing burger menu icon appears on smaller resolution.

What do you think? We can check & give the code