:root {
  --color: #111;
  --bd-bg-color: #111;
}

body {
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 100vh;
  transition: 0.4s linear;
}

body.dark {
  background-color: var(--bd-bg-color);
  --color: #fff;
}

p {
  margin-right: 10px;
  font-weight: 700;
  font-family: helvetica;
  color: var(--color);
  padding: 5px;
  border: 2px solid var(--color);
  border-radius: 4px;
}

.outer {
  position: relative;
  width: 60px;
  height: 20px;
  border: 1px solid var(--color);
  border-radius: 25px;
  cursor: pointer;
}

.inner {
  content: "";
  position: absolute;
  width: 16px;
  height: 16px;
  left: 3px;
  top: 2px;
  border-radius: 50%;
  background-color: var(--color);
  transition: all 0.4s ease;
}

.toggle {
  left: 40px;
}