:root {
  --main-color: #f3f1ec;
  --main-background-color: #171717;
  --bar-width: 30px;
  --bar-height: 2px;
  --hamburger-gap: 6px;
  --hamburger-background: transparent;
  --hamburger-margin: 20px;
  --animation-timing: 200ms ease-in-out;
  --hamburger-height: calc(
    (var(--bar-height) * 3) + (var(--hamburger-gap) * 2)
  );
}

body {
  margin: 0;
  background-color: var(--main-background-color);
  color: var(--main-color);
  font-family: "Geist";
  display: flex;
  justify-content: center;
  align-items: center;
}

header {
  width: 100vw;
  top: 0;
  left: 0;
  height: 40px;
}

#welcome-message {
  display: flex;
  flex-direction: column;
  align-items: center;
}

.hamburger-menu {
  /* square root of 2: 1.41421356237 */
  --x-width: calc(var(--hamburger-height) * 1.41421356237);
  display: flex;
  flex-direction: column;
  gap: var(--hamburger-gap);
  z-index: 2;
  cursor: pointer;
  position: absolute;
  top: var(--hamburger-margin);
  right: var(--hamburger-margin);
}

/* creates 3 bars of menu*/
.hamburger-menu::before,
.hamburger-menu input,
.hamburger-menu::after {
  content: "";
  width: var(--bar-width);
  height: var(--bar-height);
  background-color: var(--main-color);
  border-radius: 50px;
  transform-origin: left center;
  transition:
    opacity var(--animation-timing),
    width var(--animation-timing),
    rotate var(--animation-timing),
    translate var(--animation-timing);
}

.hamburger-menu input {
  appearance: none;
  padding: 0;
  margin: 0;
  outline: none;
  pointer-events: none;
}

.hamburger-menu:has(input:checked)::before {
  rotate: 45deg;
  width: var(--x-width);
  /* Add offset for bar, in math we deal with thin lines, negative to move up */
  translate: 0 calc(var(--bar-height) / -2);
}
.hamburger-menu:has(input:checked)::after {
  rotate: -45deg;
  width: var(--x-width);
  /* Add offset for bar, in math we deal with thin lines */
  translate: 0 calc(var(--bar-height) / 2);
}

.hamburger-menu input:checked {
  opacity: 0;
  width: 0;
}

.sidebar {
  position: fixed;
  right: 0;
  top: 0;
  background-color: var(--hamburger-background);
  background-image: linear-gradient(
    to right,
    rgba(239, 239, 239, 0.06),
    var(--hamburger-background)
  );
  min-height: 100vh;
  background-color: var(--main-background-color);
  z-index: 1;
  width: 200px;
  translate: 100%;
  transition: translate var(--animation-timing);
}

body:has(.hamburger-menu input:checked) .sidebar {
  translate: 0;
}

.sidebar nav {
  margin-top: calc(var(--hamburger-height) * 4);
}

nav {
  display: flex;
  flex-direction: column;
  align-items: center;
}