* {
  box-sizing: border-box;
}
body {
  margin: 0;
  font-family: 'Segoe UI', sans-serif;
  background-color: #000;
  color: white;
  display: flex;
  flex-direction: column;
  height: 100vh;
}

header, footer {
  padding: 10px 20px;
  background-color: #111;
  text-align: center;
}

main {
  display: flex;
  flex: 1;
  overflow: hidden;
}

#ui {
  width: 350px;
  background-color: #1e1e1e;
  padding: 15px;
  overflow-y: auto;
  border-right: 2px solid #333;
}

#canvas-area {
  flex: 1;
  position: relative;
}

#fireworkCanvas {
  width: 100%;
  height: 100%;
  display: block;
}

#doc {
  width: 350px;
  background-color: #1e1e1e;
  padding: 15px;
  overflow-y: auto;
  border-left: 2px solid #333;
}

label, input, button {
  display: block;
  margin-bottom: 10px;
  width: 100%;
}

button {
  padding: 8px;
  font-weight: bold;
  border-radius: 6px;
  background: #444;
  color: white;
  border: none;
  cursor: pointer;
}

button:hover {
  background: #666;
}

h2, h3 {
  margin-top: 0;
  color: #ffcc00;
}

pre, textarea {
  background: #222;
  color: #0f0;
  padding: 10px;
  border-radius: 6px;
  white-space: pre-wrap;
  overflow: auto;
}