nav {
  position: fixed;
  top: 0;
  left: 0;
  height: 3rem;
  width: 100%;
  display: flex;
  justify-content: space-between;
  align-items: center;
  background: var(--clr-blu-1);
  box-shadow: 0 2px 5px rgba(0,0,0,0.5);
  z-index: 999;
}

nav * {
  color: var(--clr-ylw-1);
}

nav a {
  text-decoration: none;
}

nav img {
  height: 3.5rem;
  padding: 0 5%;
  transition: var(--main-transition);
}

nav img[src]:hover {
  filter: brightness(1.2);
}
nav ul {
  position: relative;
  width: 50%;
  height: 100%;
  display: flex;
  justify-content: space-around;
  align-items: center;
  background: var(--clr-blu-1);
}

.nav-item {
  position: relative;
  font-size: 1rem;
  list-style: none;
  cursor: pointer;
}

.nav-item:hover:before {
  transform: translateX(-50%) scaleX(1);
}
.nav-item:hover {
  filter: brightness(1.2);
}

.nav-item:before {
  content: "";
  position: absolute;
  bottom: -2px;
  left: 50%;
  transform: translateX(-50%) scaleX(0);
  width: 100%;
  height: 100%;
  border-bottom: 2px solid var(--clr-ylw-1);
  transition: var(--main-transition);
  z-index: -1;
}

.ul-overlay {
  display: none;
}

.burger {
  position: absolute;
  right: 2px;
  outline: 0;
  border: none;
  display: none;
  background: transparent;
}

#menu-toggle {
  position: absolute;
  right: 2px;
  display: none;
}

@media (max-width: 800px) {
  .nav-item {
    font-size: 15px;
  }
}

@media (max-width: 700px) {
  nav {
    height: 4rem;
  }
  nav img {
    height: 4.5rem;
  }
  nav ul {
    height: unset;
    position: fixed;
    transform: translateY(-100%);
    top: 0;
    width: 100vw;
    display: flex;
    justify-content: center;
    align-items: center;
    flex-direction: column;
    transform-origin: top;
    background: var(--clr-blu-1);
    transition: transform var(--main-transition);
    box-shadow: 0 2px 5px rgba(0,0,0,0.5);
    z-index: -1;
  }
  .ul-overlay {
    display: block;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 4rem;
    background: var(--clr-blu-1);
    z-index: -1;
  }
  ul a, .nav-item {
    padding: 1%;
    width: 100%;
    text-align: center;
  }
  .nav-item:hover:before {
    transform: translateX(-50%) scaleX(0);
  }
  .burger {
    position: absolute;
    display: flex;
    justify-content: space-evenly;
    align-items: center;
    flex-direction: column;
    cursor: pointer;
    width: 50px;
    height: 40px;
    border-radius: 5px;
  }
  .burger span {
    width: 80%;
    height: 0;
    border-top: 2px solid var(--clr-ylw-1);
  }
  #menu-toggle:checked + label {
    box-shadow: 0 0 2px var(--clr-ylw-1);
  }
  #menu-toggle:checked ~ ul {
    transform: translateY(3rem);
  }
}