.demo-grid {
  display: grid;
  grid-template-columns: 1fr 360px;
  gap: 16px;
  align-items: start;
}

.stage-container {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 16px;
  position: relative;
  display: grid;
  place-items: center;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.25);
}

.stage {
  width: 100%;
  max-width: 960px;
  aspect-ratio: 16/9;
  background: #0f1218;
  border: 1px solid var(--border);
  border-radius: 12px;
  overflow: hidden;
  display: grid;
  place-items: center;
}

.stage-inner {
  display: grid;
  gap: 12px;
  text-align: center;
  padding: 12px;
}
.stage-inner h2 {
  margin: 0;
  font-size: 22px;
  letter-spacing: 0.3px;
}

/* CSS 降級示意：純 CSS 響應式，無需鎖向即可適應 */
.portrait-only {
  display: none;
}
.landscape-only {
  display: none;
}

@media (orientation: portrait) {
  .portrait-only {
    display: block;
  }
}
@media (orientation: landscape) {
  .landscape-only {
    display: block;
  }
}

.status-row {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 10px;
  width: 100%;
  max-width: 960px;
  margin: 6px auto 0;
}
.status-box {
  background: var(--panel-2);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 16px;
  text-align: center;
}
.status-label {
  font-size: 11px;
  color: var(--muted);
  margin-bottom: 8px;
  letter-spacing: 1px;
  font-weight: 600;
}
.status-value {
  font-size: 20px;
  font-weight: 700;
  color: var(--text);
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas,
    "Liberation Mono", monospace;
}

.control-panel {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 14px;
  display: grid;
  gap: 12px;
}
.control-section {
  background: var(--panel-2);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 12px;
}
.control-section h3 {
  margin: 0 0 8px;
  font-size: 13px;
  color: #cfd6e6;
  font-weight: 600;
}
.control-section .hint {
  font-size: 12px;
  color: #7e8aa6;
  margin-top: 8px;
}
.control-section .btn-row {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
  margin-top: 8px;
}
.control-section button {
  flex: 1;
  min-width: 120px;
  background: #0f1218;
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 8px 10px;
  cursor: pointer;
}

button:disabled {
  cursor: not-allowed;
  opacity: 0.5;
}

.btn-group-label {
  margin-top: 8px;
}
.support-status {
  margin-bottom: 8px;
}

/* Log 面板 */
.log-section .log {
  height: 180px;
  overflow: auto;
  background: #0e1423;
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 10px;
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas,
    "Liberation Mono", monospace;
  font-size: 12px;
}
.log-line {
  opacity: 0.95;
}

@media (max-width: 900px) {
  .layout {
    grid-template-columns: 1fr;
  }
  .demo-grid {
    grid-template-columns: 1fr;
  }
  .status-row {
    grid-template-columns: 1fr;
  }
}