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                <div class="demo fancy-gradient fancy-gradient--rainbow">
  <h1 class="title">
    Royal Rainbow!


/// Highly Customizable Gradient Background
/// This background is created using a solid background color, and then four
/// radial gradient "spotlights". These spotlights are entirely defined with
/// custom properties, so they can be easily tweaked. For each spotlight,
/// you can change the color, width, height, and positioning.
/// Colors from

:root {
  // overall gradient background color
  --gradient_bg_color: #006dca; // blue

  // spot 1 - top left corner
  --gradient_spot1_color: #001a39; // dark blue
  --gradient_spot1_w: 75vw;
  --gradient_spot1_h: 75vh;
  --gradient_spot1_x: 0;
  --gradient_spot1_y: 0;

  // spot 2 - top right corner
  --gradient_spot2_color: #9b70ff; // violet
  --gradient_spot2_w: 75vw;
  --gradient_spot2_h: 75vh;
  --gradient_spot2_x: 100%;
  --gradient_spot2_y: 0;

  // spot 3 - bottom right corner
  --gradient_spot3_color: #42ffc6; // aquamarine
  --gradient_spot3_w: 75vw;
  --gradient_spot3_h: 75vh;
  --gradient_spot3_x: 100%;
  --gradient_spot3_y: 100%;

  // spot 4 - bottom left corner
  --gradient_spot4_color: #ff3b8d; // rose
  --gradient_spot4_w: 75vw;
  --gradient_spot4_h: 75vh;
  --gradient_spot4_x: 0;
  --gradient_spot4_y: 100%;

.fancy-gradient {
  background-color: var(--gradient_bg_color);
  background-image: radial-gradient(
      var(--gradient_spot1_w) var(--gradient_spot1_h) at left
        var(--gradient_spot1_x) top var(--gradient_spot1_y),
      var(--gradient_spot2_w) var(--gradient_spot2_h) at left
        var(--gradient_spot2_x) top var(--gradient_spot2_y),
      var(--gradient_spot3_w) var(--gradient_spot3_h) at left
        var(--gradient_spot3_x) top var(--gradient_spot3_y),
      var(--gradient_spot4_w) var(--gradient_spot4_h) at left
        var(--gradient_spot4_x) top var(--gradient_spot4_y),

/// Royal Rainbow!
/// The spots are arranged in a diagonal line at about the same angle
/// as the text to create a rainbow effect. Note that the spots are
/// a bit offset to the left because they're stacked, so the leftmost
/// spot covers more space than the rightmost.
.fancy-gradient--rainbow {
  --gradient_spot1_color: #db0072; /* rose */
  --gradient_spot1_w: 50vw;
  --gradient_spot1_h: 100vh;
  --gradient_spot1_x: -10%;
  --gradient_spot1_y: 80%;

  --gradient_spot2_color: #ffe53e; /* yellow */
  --gradient_spot2_w: 50vw;
  --gradient_spot2_h: 100vh;
  --gradient_spot2_x: 25%;
  --gradient_spot2_y: 60%;

  --gradient_spot3_color: #00ffe4; /* teal */
  --gradient_spot3_w: 50vw;
  --gradient_spot3_h: 100vh;
  --gradient_spot3_x: 55%;
  --gradient_spot3_y: 40%;

  --gradient_spot4_color: #d150ff; /* purple */
  --gradient_spot4_w: 50vw;
  --gradient_spot4_h: 100vh;
  --gradient_spot4_x: 90%;
  --gradient_spot4_y: 20%;

/// Base Styles

.demo {
  width: 100vw;
  height: 100vh;
  position: relative;

.title {
  color: rgba(255, 255, 255, 0.8);
  font-family: ui-rounded, system-ui, sans-serif;
  font-size: clamp(32px, 9vw, 200px);
  text-align: center;
  position: absolute;
  left: 0;
  right: 0;
  top: 50%;
  transform: translateY(-50%) skew(0deg, -10deg);
  text-shadow: 0.025em 0.025em 0.025em rgba(0,0,0,0.1);

* {
  margin: 0;