body{font-family:Arial,sans-serif;margin:0;background:#f0f2f5}.app{max-width:1100px;margin:0 auto;padding:10px}header{display:flex;justify-content:space-between;align-items:center;margin-bottom:10px}.btn{margin:6px;padding:8px 12px;background:#007bff;color:#fff;border:none;border-radius:4px;cursor:pointer}.btn.small{padding:6px 10px;font-size:12px}.btn.tiny{padding:4px 6px;font-size:11px}.btn.danger{background:#dc3545}.auth{background:#fff;padding:20px;border-radius:8px;max-width:400px;margin:40px auto}.auth input{display:block;width:100%;margin:6px 0;padding:8px}.main{display:flex;gap:10px}.sidebar{width:280px;background:#fff;padding:10px;border-radius:8px}.sidebar ul{list-style:none;padding:0}.sidebar li{display:flex;justify-content:space-between;align-items:center;padding:6px 0;border-bottom:1px solid #eee}.sidebar li.online{background:#e6ffed}.chatbox{margin-top:10px}.messages{height:200px;overflow:auto;background:#fafafa;padding:8px;border:1px solid #eee;border-radius:4px;margin:8px 0}.msg{padding:4px}.msg.mine{text-align:right}.content{flex:1;background:#fff;padding:10px;border-radius:8px}.videos{display:flex;gap:20px}.video{width:320px;height:240px;background:#000;border-radius:6px}.controls{margin-top:10px}.incoming{background:#fff3cd;padding:8px;border:1px solid #ffeeba;border-radius:6px;display:inline-block}