nav {
  width: 100%;
  padding: 0;
  margin: 0;
}

nav ul {
  padding: 0;
  margin: 0;
  width: 100%;
  font-size: 0;
  list-style: none;
}

nav li {
  display: inline-block;
  padding: 0;
  margin: 0;
  width: 50%;
}

nav li a {
  display: block;
  text-align: center;
  text-decoration: none;
  font-size: 16px;
  font-weight: bold;
  color: #000;
  background: #efefef;
  padding: 20px 5px;
  text-transform: uppercase;
  border-bottom: 1px solid #03316f;


}

nav li a.active {
  background: #fff;
  color: #03316f;
  border: 1px solid #03316f;
  border-bottom: none;

  &:hover{
    cursor: default;
  }
}

nav {
  width: 100%;
  padding: 0;
  margin: 0;
}

nav ul {
  padding: 0;
  margin: 0;
  width: 100%;
  font-size: 0;
  list-style: none;
}

nav li {
  display: inline-block;
  padding: 0;
  margin: 0;
  width: 50%;
}

nav li a {
  display: block;
  text-align: center;
  text-decoration: none;
  font-size: 16px;
  font-weight: bold;
  color: #000;
  background: #efefef;
  padding: 20px 5px;
  text-transform: uppercase;
  border-bottom: 1px solid #03316f;


}

nav li a.active {
  background: #fff;
  color: #03316f;
  border: 1px solid #03316f;
  border-bottom: 1px solid #fff;

  &:hover{
    cursor: default;
  }
}

Fix a 'pixel' problem at nav border
Fix a 'pixel' problem at nav border
