:root {
  --bg: #05070f;
  --panel: #0d101a;
  --panel-stroke: rgba(255, 255, 255, 0.08);
  --text: #e7ecff;
  --nav-height: 78px;
  --nav-gap: 0px;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: "Helvetica Neue", Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
  height: 100vh;
  overflow: hidden;
}

.viewer {
  height: calc(100vh - var(--nav-height));
  display: flex;
  align-items: stretch;
  justify-content: stretch;
  padding: 0;
}

.frame {
  width: 100vw;
  height: 100%;
  border-radius: 0;
  overflow: hidden;
  border: none;
  background: var(--panel);
}

.frame iframe {
  width: 100%;
  height: 100%;
  border: none;
  background: #070a12;
}

.nav {
  position: fixed;
  left: 0;
  bottom: 0;
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
  min-height: var(--nav-height);
  padding: 12px 12px calc(12px + env(safe-area-inset-bottom));
  background: rgba(10, 12, 18, 0.9);
  border-top: 1px solid var(--panel-stroke);
  backdrop-filter: blur(10px);
}

.nav__info {
  flex: 1;
  margin-right: auto;
  font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  font-size: 14px;
  font-weight: 700;
  text-align: left;
  color: var(--text);
  opacity: 0.9;
}

.nav button {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  border: 1px solid var(--panel-stroke);
  background: linear-gradient(135deg, rgba(255, 255, 255, 0.06), rgba(255, 255, 255, 0.02));
  color: var(--text);
  font-size: 18px;
  cursor: pointer;
  transition: transform 0.12s ease, border-color 0.2s ease;
}

.nav button:hover {
  transform: translateY(-2px);
  border-color: rgba(255, 255, 255, 0.2);
}

.nav button:active {
  transform: translateY(0);
}