:root {
  --color-primary: #2c3e50;
  --color-secondary: #3498db;
  --color-light: #ecf0f1;
  --grid-size: 20px;
}
body {
  font-family: 'Roboto', sans-serif;
  margin: 0;
  background-color: #f5f7fa;
  overflow: hidden;
}
#app {
  width: 100vw;
  height: 100vh;
  display: flex;
  position: relative;
}
#lienzo {
  flex: 1;
  border: 1px solid var(--color-primary);
  background-color: white;
  background-image: 
    linear-gradient(to right, #f5f5f5 1px, transparent 1px),
    linear-gradient(to bottom, #f5f5f5 1px, transparent 1px);
  background-size: var(--grid-size) var(--grid-size);
}
#toolbar {
  width: 300px;
  background: white;
  box-shadow: -2px 0 10px rgba(0,0,0,0.1);
  padding: 10px;
}
@media (max-width: 768px) {
  #toolbar {
    width: 100%;
    height: 200px;
    bottom: 0;
    top: auto;
  }
}