.header
{
    background-color: red;
    height: 50px;
}
body { margin: 0; overflow: hidden; background: #000; font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif; }
#gpuCanvas { display: block; width: 100vw; height: 100vh; }

#ui-panel {
    position: absolute;
    top: 20px;
    right: 20px;
    background: rgba(20, 20, 25, 0.85);
    backdrop-filter: blur(8px);
    padding: 20px;
    border-radius: 8px;
    border: 1px solid #333;
    width: 260px;
    display: flex;
    flex-direction: column;
    gap: 15px;
    color: #eee;
    box-shadow: 0 10px 30px rgba(0,0,0,0.8);
}

#ui-panel h2 { margin: 0 0 5px 0; font-size: 18px; border-bottom: 1px solid #444; padding-bottom: 10px; }
#ui-panel label { font-size: 11px; text-transform: uppercase; letter-spacing: 1px; color: #aaa; }

#ui-panel select, #ui-panel input { 
    width: 100%; padding: 8px; background: #111; border: 1px solid #555; 
    color: #fff; border-radius: 4px; box-sizing: border-box; outline: none;
}
#ui-panel select:focus, #ui-panel input:focus { border-color: #0088ff; }

#ui-panel .row { display: flex; gap: 8px; }
#ui-panel .row input { flex: 1; font-family: monospace; }

#ui-panel button {
    padding: 10px; cursor: pointer; background: #333; color: white;
    border: none; border-radius: 4px; font-weight: bold; transition: 0.2s;
}
#ui-panel button:hover { background: #444; }

#ui-panel button.primary { background: #0066cc; margin-top: 10px; }
#ui-panel button.primary:hover { background: #0088ff; }

#gpuCanvas {
    display: block; width: 100vw; height: 100vh;
    touch-action: none; 
    -webkit-touch-callout: none;
    -webkit-user-select: none;
    user-select: none;
}

@media screen and (max-width: 800px) {
    #ui-panel {
        top: 10px; right: 10px;
        width: 180px; /* Keskenyebb panel */
        padding: 10px;
        font-size: 10px;
        max-height: 90vh;
        overflow-y: auto;
    }
    #ui-panel h2 { font-size: 14px; }
    #ui-panel button, #ui-panel select, #ui-panel input { padding: 5px; }
}

#orientation-warning {
    display: none;
    position: absolute; top: 0; left: 0; width: 100vw; height: 100vh;
    background: rgba(0,0,0,0.9); color: white;
    justify-content: center; align-items: center;
    font-size: 24px; text-align: center; z-index: 9999;
}
@media screen and (orientation: portrait) and (max-width: 600px) {
    #orientation-warning { display: flex; }
}