@media (max-width: 600px) {
    .container {
        padding: 15px;
        margin: 10px;
    }
    
    h1 { 
        font-size: 16px;
        letter-spacing: 1px;
    }
    
    .subtitle {
        font-size: 8px;
    }
    
    .controls {
        gap: 8px;
        flex-wrap: wrap;
    }
    
    .controls button {
        padding: 10px 8px;
        font-size: 8px;
        letter-spacing: 0.5px;
        flex: 1 1 calc(50% - 4px);
        min-width: 0;
    }
    
    .difficulty-content h3 {
        font-size: 14px;
    }
    
    .diff-label {
        font-size: 10px;
    }
    
    .diff-value {
        font-size: 8px;
    }
    
    .difficulty-menu-buttons {
        flex-direction: column;
        gap: 8px;
    }
    
    .difficulty-menu-btn {
        max-width: 100%;
        font-size: 8px;
        padding: 10px 12px;
    }
    
    .tile { 
        font-size: 18px; 
    }
    
    .tile[data-value="128"],
    .tile[data-value="256"],
    .tile[data-value="512"] { 
        font-size: 16px; 
    }
    
    .tile[data-value="1024"],
    .tile[data-value="2048"] { 
        font-size: 14px; 
    }
    
    .tile[data-value="4096"],
    .tile[data-value="8192"],
    .tile[data-value="16384"],
    .tile[data-value="32768"],
    .tile[data-value="65536"] {
        font-size: 12px;
    }
    
    .game-board {
        gap: 8px;
        padding: 8px;
    }
    
    .score-columns {
        flex-direction: column;
        align-items: center;
        gap: 10px;
    }
    
    .score-column {
        max-width: 100%;
        width: 100%;
    }
    
    .score-label {
        font-size: 8px;
    }
    
    .score {
        font-size: 14px;
    }
    
    .scoreboard-content h3,
    .instructions-content h3 {
        font-size: 12px;
    }
    
    .scoreboard-content {
        padding: 12px;
        max-height: 78vh;
        width: 96%;
    }
    
    .scoreboard-content h3 {
        font-size: 11px;
        margin-bottom: 10px;
    }
    
    .mode-selector-container {
        margin-bottom: 10px;
        min-height: 40px;
    }
    
    .dropdown-selected {
        padding: 9px 14px;
        font-size: 9px;
    }
    
    .instructions-content p {
        font-size: 8px;
    }
    
    .game-over h2 {
        font-size: 18px;
    }
    
    .game-over p {
        font-size: 11px;
    }
}

@media (max-width: 400px) {
    h1 {
        font-size: 14px;
        letter-spacing: 0.5px;
    }
    
    .subtitle {
        font-size: 7px;
    }
    
    .score-container {
        padding: 8px 12px;
    }
    
    .score {
        font-size: 12px;
    }
    
    .score-label {
        font-size: 7px;
    }
    
    .controls {
        gap: 6px;
    }
    
    .controls button {
        padding: 8px 6px;
        font-size: 7px;
        flex: 1 1 calc(50% - 3px);
    }
    
    .difficulty-content h3 {
        font-size: 12px;
    }
    
    .diff-label {
        font-size: 9px;
    }
    
    .diff-value {
        font-size: 7px;
    }
    
    .tile {
        font-size: 16px;
    }
    
    .tile[data-value="128"],
    .tile[data-value="256"],
    .tile[data-value="512"] {
        font-size: 14px;
    }
    
    .tile[data-value="1024"],
    .tile[data-value="2048"] {
        font-size: 12px;
    }
    
    .tile[data-value="4096"],
    .tile[data-value="8192"],
    .tile[data-value="16384"],
    .tile[data-value="32768"],
    .tile[data-value="65536"] {
        font-size: 10px;
    }
}