* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: Arial, Helvetica, sans-serif;
}

body {
  transition: background-color 0.3s ease;
}

nav {
  background: #212121;
  padding: 15px;
  text-align: center;
}

nav a {
  color: white;
  text-decoration: none;
  font-weight: bold;
}

/* ===== Canvas ===== */
.canvas {
  margin: 100px auto;
  width: 80%;
  text-align: center;
}

.colors {
  margin: 30px 0;
}

/* ===== Color Buttons ===== */
.button {
  width: 100px;
  height: 100px;
  border: 2px solid #000;
  display: inline-block;
  margin: 10px;
  cursor: pointer;
  transition: all 0.2s ease;
}

/* Selected state */
.button.active {
  border: 5px solid #000;
  box-shadow: 0 0 10px rgba(0,0,0,0.4);
}

/* Colors */
#grey { background-color: grey; }
#white { background-color: white; }
#blue { background-color: blue; }
#yellow { background-color: yellow; }
#purple { background-color: purple; }

/* ===== Text ===== */
h2 {
  font-size: 20px;
  margin-top: 30px;
  color: #000;
}

h2 span {
  display: block;
  margin-top: 12px;
  font-size: 18px;
  font-weight: 600;
  color: #000;
}