/*  — 全屏 iframe，无顶栏 */
:root {
  --bg: #131313;
  --on-bg: #e5e2e1;
  --on-surface-variant: #e9bcb6;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html.dark,
html {
  color-scheme: dark;
  height: 100%;
}

body.app-shell {
  margin: 0;
  min-height: 100%;
  height: 100%;
  background: var(--bg);
  color: var(--on-bg);
  font-family: "Segoe UI", "Microsoft YaHei UI", "PingFang SC", system-ui, sans-serif;
  font-size: 15px;
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
  display: flex;
  flex-direction: column;
}

.main-embed {
  flex: 1;
  min-height: 0;
  display: flex;
  flex-direction: column;
  padding: 0;
}

.embed-frame {
  flex: 1;
  min-height: 0;
  background: rgba(14, 14, 14, 0.75);
  overflow: hidden;
  position: relative;
}

.embed-frame.empty {
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 1.25rem;
  color: var(--on-surface-variant);
  font-style: italic;
  font-size: 0.95rem;
}

.embed-frame.has-url {
  padding: 0;
}

.embed-iframe {
  position: absolute;
  left: 0;
  top: 0;
  width: 100%;
  height: 100%;
  border: none;
  background: #fff;
}