.start-coding-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  border: none;
  border-radius: 8px;
  background: transparent;
  cursor: pointer;
  padding: 0;
  flex-shrink: 0;
  transition: background 0.15s, box-shadow 0.15s;
  position: relative;
}

.start-coding-icon {
  width: 20px;
  height: 20px;
  display: block;
  object-fit: contain;
  transition: opacity 0.15s, filter 0.15s;
}

.start-coding-btn:hover {
  background: rgba(0, 0, 0, 0.06);
}

.start-coding-btn.active {
  background: transparent;
}

.start-coding-btn.active .start-coding-icon {
  filter: drop-shadow(0 0 4px rgba(99, 102, 241, 0.5));
}

/* Theme overrides live in theme_controller.css */