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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    overflow: hidden;
    background: linear-gradient(135deg, #2C3E50 0%, #3498DB 100%);
    touch-action: none;
}

#game-canvas {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    display: block;
}

#ui-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    padding: 15px 20px;
    pointer-events: none;
    z-index: 10;
}

#ui-overlay h1 {
    text-align: center;
    color: white;
    font-size: 2rem;
    font-weight: 800;
    text-transform: uppercase;
    letter-spacing: 4px;
    text-shadow: 
        2px 2px 0 #27AE60,
        4px 4px 0 #1E8449,
        6px 6px 12px rgba(0, 0, 0, 0.4);
    margin-bottom: 10px;
    background: linear-gradient(180deg, #FFFFFF 0%, #E8F8F5 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    filter: drop-shadow(3px 3px 4px rgba(0,0,0,0.3));
}

#controls {
    position: fixed;
    top: 70px;
    right: 15px;
    display: flex;
    flex-direction: column;
    gap: 8px;
    pointer-events: auto;
}

.game-button {
    background: linear-gradient(145deg, #27AE60, #1E8449);
    border: none;
    padding: 10px 20px;
    border-radius: 25px;
    font-size: 0.9rem;
    font-weight: 600;
    color: white;
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 8px;
    box-shadow: 
        0 4px 15px rgba(39, 174, 96, 0.4),
        inset 0 1px 0 rgba(255, 255, 255, 0.2);
    transition: all 0.2s ease;
    text-shadow: 1px 1px 2px rgba(0,0,0,0.2);
}

.game-button:hover {
    transform: translateY(-2px);
    box-shadow: 
        0 6px 20px rgba(39, 174, 96, 0.5),
        inset 0 1px 0 rgba(255, 255, 255, 0.3);
    background: linear-gradient(145deg, #2ECC71, #27AE60);
}

.game-button:active {
    transform: translateY(0);
    box-shadow: 
        0 2px 8px rgba(39, 174, 96, 0.3),
        inset 0 2px 4px rgba(0, 0, 0, 0.1);
}

.btn-icon {
    font-size: 1.1rem;
}

#instructions {
    position: fixed;
    bottom: 15px;
    left: 15px;
    background: rgba(255, 255, 255, 0.95);
    padding: 12px 18px;
    border-radius: 15px;
    box-shadow: 
        0 4px 20px rgba(0, 0, 0, 0.15),
        0 0 0 1px rgba(39, 174, 96, 0.2);
    pointer-events: none;
    backdrop-filter: blur(10px);
}

#instructions p {
    color: #2C3E50;
    font-size: 0.85rem;
    margin: 4px 0;
    display: flex;
    align-items: center;
    gap: 8px;
}

#instructions .icon {
    font-size: 1rem;
    width: 24px;
    text-align: center;
}

/* Loading screen */
#loading-screen {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background: linear-gradient(135deg, #1E8449 0%, #27AE60 50%, #2ECC71 100%);
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    z-index: 1000;
    transition: opacity 0.6s ease, visibility 0.6s ease;
}

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

.loader-container {
    text-align: center;
}

.frog-loader {
    font-size: 80px;
    animation: hop 0.6s ease-in-out infinite;
    filter: drop-shadow(0 10px 20px rgba(0,0,0,0.3));
}

@keyframes hop {
    0%, 100% {
        transform: translateY(0) scale(1);
    }
    50% {
        transform: translateY(-20px) scale(1.1);
    }
}

#loading-screen p {
    color: white;
    font-size: 1.3rem;
    margin-top: 20px;
    font-weight: 600;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.2);
    letter-spacing: 1px;
}

/* Piece highlight effect */
.piece-selected {
    filter: drop-shadow(0 0 15px rgba(255, 235, 59, 0.8));
}

/* Mobile responsive */
@media (max-width: 768px) {
    #ui-overlay h1 {
        font-size: 1.3rem;
        letter-spacing: 2px;
    }
    
    #controls {
        top: 55px;
        right: 10px;
    }
    
    .game-button {
        padding: 8px 14px;
        font-size: 0.8rem;
        border-radius: 20px;
    }
    
    .btn-icon {
        font-size: 1rem;
    }
    
    #instructions {
        bottom: 10px;
        left: 10px;
        padding: 10px 14px;
        border-radius: 12px;
    }
    
    #instructions p {
        font-size: 0.75rem;
        margin: 3px 0;
    }
    
    #instructions .icon {
        font-size: 0.9rem;
        width: 20px;
    }
    
    .frog-loader {
        font-size: 60px;
    }
    
    #loading-screen p {
        font-size: 1.1rem;
    }
}

/* Very small screens */
@media (max-width: 480px) {
    #ui-overlay h1 {
        font-size: 1rem;
        letter-spacing: 1px;
    }
    
    #instructions {
        display: none; /* Hide on very small screens */
    }
}

/* Hover effects disabled on touch devices */
@media (hover: none) {
    .game-button:hover {
        transform: none;
        box-shadow: 
            0 4px 15px rgba(39, 174, 96, 0.4),
            inset 0 1px 0 rgba(255, 255, 255, 0.2);
        background: linear-gradient(145deg, #27AE60, #1E8449);
    }
}