* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    overflow: hidden;
    background: #f5f5f5;
    color: #333;
    touch-action: none;
    -webkit-touch-callout: none;
    -webkit-user-select: none;
    user-select: none;
}

/* Loading Screen */
#loading-screen {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: #f5f5f5;
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    transition: opacity 0.5s ease;
}

#loading-screen.hidden {
    opacity: 0;
    pointer-events: none;
}

.loading-content {
    text-align: center;
}

.loader {
    width: 50px;
    height: 50px;
    border: 3px solid #e0e0e0;
    border-top-color: #667eea;
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin: 0 auto 15px;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

.loading-content p {
    font-size: 16px;
    color: #666;
}

#loading-progress {
    font-size: 13px;
    color: #999;
    margin-top: 8px;
}

/* 3D Canvas */
#canvas-container {
    width: 100vw;
    height: 100vh;
    position: fixed;
    top: 0;
    left: 0;
}

/* Start Screen */
#start-screen {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, #f5f5f7 0%, #e8e8ed 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 500;
}

.start-content {
    text-align: center;
    padding: 30px;
}

.start-content h1 {
    font-size: 36px;
    font-weight: 300;
    color: #222;
    margin-bottom: 8px;
    letter-spacing: 1px;
}

.start-content > p {
    font-size: 15px;
    color: #666;
    margin-bottom: 30px;
}

#enter-btn {
    background: #222;
    color: white;
    border: none;
    padding: 14px 36px;
    font-size: 15px;
    font-weight: 500;
    cursor: pointer;
    border-radius: 4px;
    transition: background 0.3s;
}

#enter-btn:hover {
    background: #444;
}

.controls-info {
    margin-top: 35px;
    display: flex;
    justify-content: center;
    gap: 30px;
}

.control-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 6px;
}

.control-item .key {
    background: #e8e8ed;
    padding: 6px 12px;
    border-radius: 4px;
    font-size: 11px;
    font-weight: 600;
    color: #555;
}

.control-item span:last-child {
    font-size: 10px;
    color: #888;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

/* Mobile Hint */
#mobile-hint {
    display: none;
    position: fixed;
    bottom: 30px;
    left: 50%;
    transform: translateX(-50%);
    background: rgba(0, 0, 0, 0.6);
    color: white;
    padding: 10px 20px;
    border-radius: 20px;
    font-size: 13px;
    z-index: 100;
    pointer-events: none;
    animation: fadeInOut 3s ease;
}

@keyframes fadeInOut {
    0%, 100% { opacity: 0; }
    20%, 80% { opacity: 1; }
}

/* Crosshair */
#crosshair {
    display: none;
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 12px;
    height: 12px;
    border: 2px solid rgba(255, 255, 255, 0.9);
    border-radius: 50%;
    pointer-events: none;
    z-index: 100;
    transition: all 0.2s ease;
}

#crosshair.hover {
    width: 28px;
    height: 28px;
    border-color: #667eea;
    background: rgba(102, 126, 234, 0.25);
}

/* Mobile Styles */
@media (max-width: 768px) {
    #start-screen {
        display: none !important;
    }
    
    #mobile-hint {
        display: block;
    }
}

@media (max-width: 480px) {
    .start-content h1 {
        font-size: 28px;
    }
    
    .controls-info {
        gap: 20px;
    }
}