core functionality complete

src/viewer/viewer.css

@@ -0,0 +1,54 @@
+:root {
+  --bg: #1a1a2e;
+  --text: #ffffff;
+  --panel-bg: #16213e;
+}
+
+* {
+  margin: 0;
+  padding: 0;
+  box-sizing: border-box;
+}
+
+body {
+  background: var(--bg);
+  color: var(--text);
+  width: 100vw;
+  height: 100vh;
+  overflow: hidden;
+}
+
+#panels {
+  display: grid;
+  grid-template-columns: 1fr 1fr;
+  grid-template-rows: 1fr 1fr;
+  gap: 2px;
+  width: 100%;
+  height: 100%;
+}
+
+.panel {
+  background: var(--panel-bg);
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  overflow: hidden;
+  position: relative;
+}
+
+.panel.empty {
+  opacity: 0.3;
+}
+
+.panel.empty::after {
+  content: 'No video';
+  color: #64748b;
+  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
+  font-size: 14px;
+}
+
+.panel video {
+  width: 100%;
+  height: 100%;
+  object-fit: contain;
+}