:root {
  --bg: #050505;
  --text: #f5f5f5;
  --app-width: 100vw;
  --app-height: 100vh;
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html,
body {
  width: 100%;
  height: 100%;
  min-height: 100%;
  background: var(--bg);
  color: var(--text);
  font-family: Arial, Helvetica, sans-serif;
  overflow: hidden;
  overscroll-behavior: none;
  touch-action: manipulation;
}

body {
  width: var(--app-width);
  height: var(--app-height);
  min-height: var(--app-height);
}

.welcome-overlay {
  position: fixed;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(5, 5, 5, 0.94);
  z-index: 10;
}

.welcome-overlay[hidden] {
  display: none;
}

.welcome-card {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 18px;
  padding: 24px;
}

.welcome-title {
  color: #f5f5f5;
  font: 700 28px/1.2 Arial, Helvetica, sans-serif;
  letter-spacing: 0.04em;
  text-align: center;
}

.welcome-button {
  appearance: none;
  border: 1px solid rgba(255, 255, 255, 0.22);
  border-radius: 18px;
  padding: 18px 28px;
  background: #f2f2f2;
  color: #111;
  font: 700 20px/1 Arial, Helvetica, sans-serif;
  letter-spacing: 0.03em;
  cursor: pointer;
  min-width: 200px;
  min-height: 60px;
}

#appCanvas {
  display: block;
  width: var(--app-width);
  height: var(--app-height);
  user-select: none;
  -webkit-user-select: none;
  touch-action: manipulation;
  -webkit-tap-highlight-color: transparent;
  cursor: pointer;
}