html, body {
  margin: 0;
  padding: 0;
  width: 100%;
  height: 100%;
  overflow: hidden;
  background: #000;
  color: #fff;
  font-family: -apple-system, BlinkMacSystemFont, "Helvetica Neue", Helvetica, Arial, system-ui, sans-serif;
}

#header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: 56px;
  padding: 0 18px;
  display: flex;
  align-items: center;
  justify-content: flex-start;
  background: rgba(0, 0, 0, 0.9);
  backdrop-filter: blur(18px);
  z-index: 10;
  box-sizing: border-box;
}

#header-title {
  font-family: 'PPNeueBit', monospace;
  font-weight: 800;
  letter-spacing: 0.12em;
  font-size: 24px;
  text-transform: uppercase;
}

#viewer {
  position: fixed;
  inset: 0;
  top: 56px; /* below header */
  transition: width 0.3s ease, right 0.3s ease;
}

#overlay {
  position: fixed;
  left: 0;
  right: 0;
  bottom: 0;
  padding: 10px 16px 20px;
  background: linear-gradient(to top, rgba(0,0,0,0.8), transparent);
  font-size: 14px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  pointer-events: none;
}

#overlay span {
  pointer-events: auto;
}

#overlay a {
  color: #4da3ff;
  text-decoration: none;
  pointer-events: auto;
}

#helper-controls {
  position: fixed;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  z-index: 50;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  pointer-events: none;
  opacity: 0;
  transition: opacity 1s ease-in-out;
}

#helper-controls:not(.hidden) {
  opacity: 1;
}

#helper-controls.hidden {
  opacity: 0;
}

#helper-controls .helper-icon {
  font-size: 32px;
  color: #fff;
  font-weight: 300;
}

#helper-controls .helper-text {
  font-family: 'PPNeueBit', monospace;
  font-size: 20px;
  color: #fff;
  text-transform: lowercase;
  letter-spacing: 0.1em;
}