.app {
  height: 100vh;
  overscroll-behavior-y: none;
  display: flex;
  position: relative;
}

.burger {
  width: 30px;
  height: 22px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  background: none;
  border: none;
  cursor: pointer;
  padding: 0;
  position: absolute;
  top: 20px;
  left: 20px;
  z-index: 1000;
}

.burger span {
  height: 4px;
  background: #000;
  border-radius: 2px;
  transition: 0.3s;
}

.burger.active span:nth-child(1) {
  transform: translateY(9px) rotate(45deg);
  background: #fff;
}

.burger.active span:nth-child(2) {
  opacity: 0;
}

.burger.active span:nth-child(3) {
  transform: translateY(-9px) rotate(-45deg);
  background: #fff;
}
