body {
  margin: 0;
  font-family: "Inter", "Open Sans", Arial, sans-serif;
  background-color: #f4f8fc; /* pale blue-white background */
  color: #0a2a43; /* dark navy text */
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  text-align: center;
}

header {
  background-color: #1e4d8f; /* strong medium blue */
  color: #ffffff;
  padding: 24px 0;
  margin-bottom: 32px;
  box-shadow: 0 4px 8px rgba(10, 42, 67, 0.25);
}

header h1 {
  margin: 0;
  font-size: 28px;
  letter-spacing: 1px;
  text-transform: uppercase;
}

nav {
  margin-top: 8px;
}

nav a {
  color: #ffffff;
  text-decoration: none;
  margin: 0 12px;
  font-weight: 500;
  font-size: 16px;
}

nav a:hover {
  color: #a3d4ff; /* light blue hover */
  text-decoration: underline;
}

main {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: flex-start;
  padding: 16px;
}

section {
  max-width: 820px;
  background-color: #ffffff;
  color: #0a2a43;
  padding: 28px;
  border-radius: 12px;
  box-shadow: 0 4px 16px rgba(10, 42, 67, 0.15);
}

h2 {
  color: #1e4d8f; /* same blue as header */
  margin-top: 0;
  font-size: 24px;
}

p {
  font-size: 16px;
  line-height: 26px;
  margin: 16px 0;
  color: #1e3c5a;
}

canvas {
  border: 2px solid #1e4d8f;
  border-radius: 12px;
  background-color: #f0f6ff;
  display: block;
  margin: 16px auto;
  max-width: 100%;
  height: auto;
}

.controls {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 12px;
  margin-top: 16px;
}

button {
  background-color: #1e4d8f;
  color: #ffffff;
  border: 1px solid #1e4d8f;
  padding: 10px 20px;
  border-radius: 12px;
  cursor: pointer;
  font-size: 16px;
  font-weight: 500;
  letter-spacing: 0.5px;
}

button:hover {
  background-color: #2f73d9; /* lighter blue on hover */
  border-color: #2f73d9;
}

footer {
  background-color: #1e4d8f;
  color: #ffffff;
  padding: 12px;
  font-size: 14px;
  text-align: center;
  margin-top: 32px;
  border-top: 1px solid #2f73d9;
}

.illusion {
  display: flex;
  flex-direction: row;     /* force side-by-side alignment */
  align-items: flex-start; /* top edges line up */
  justify-content: center; /* center both halves in page */
  gap: 24px;               /* space between text and canvas */
  margin: 40px auto;
  max-width: 5000px;       /* keeps page from stretching too wide */
}

/* left column: blurb */
.blurb {
  flex-basis: 30%;         /* about 1/3 of total width */
  max-width: 500px;
  text-align: left;
}

/* right column: canvas and controls */
.illusion-visual {
  flex-basis: 70%;         /* about 2/3 of total width */
  text-align: center;
}