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

body {
    font-family: 'Arial', sans-serif;
    background: linear-gradient(to bottom, #87CEEB 0%, #98D8E8 50%, #B0E0E6 100%);
    overflow: hidden;
    height: 100vh;
}

.game-container {
    position: relative;
    width: 100vw;
    height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
}

.sky-background {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(to bottom, 
        #1e3c72 0%, 
        #2a5298 20%, 
        #87CEEB 40%, 
        #98D8E8 60%, 
        #B0E0E6 80%, 
        #E0F6FF 100%);
    z-index: -1;
}

#gameCanvas {
    border: 3px solid #8B4513;
    border-radius: 10px;
    background: linear-gradient(to bottom, #87CEEB, #DEB887);
    box-shadow: 0 0 20px rgba(0,0,0,0.3);
}

.ui-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    z-index: 10;
}

.score-panel {
    position: absolute;
    top: 20px;
    left: 20px;
    background: rgba(0,0,0,0.7);
    color: white;
    padding: 15px;
    border-radius: 10px;
    font-size: 16px;
    font-weight: bold;
    pointer-events: auto;
}

.score-panel div {
    margin: 5px 0;
}

.controls {
    position: absolute;
    bottom: 20px;
    left: 50%;
    transform: translateX(-50%);
    background: rgba(0,0,0,0.7);
    color: white;
    padding: 10px 20px;
    border-radius: 25px;
    font-size: 14px;
    text-align: center;
}

.start-screen, .game-over {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 40px;
    border-radius: 20px;
    text-align: center;
    box-shadow: 0 10px 30px rgba(0,0,0,0.3);
    pointer-events: auto;
    max-width: 400px;
}

.start-screen h1 {
    font-size: 2.5em;
    margin-bottom: 20px;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.3);
}

.start-screen p, .game-over p {
    margin: 10px 0;
    font-size: 1.1em;
    line-height: 1.4;
}

.btn {
    background: linear-gradient(45deg, #FF6B6B, #FF8E53);
    color: white;
    border: none;
    padding: 15px 30px;
    font-size: 18px;
    font-weight: bold;
    border-radius: 30px;
    cursor: pointer;
    margin-top: 20px;
    transition: all 0.3s ease;
    pointer-events: auto;
}

.btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(0,0,0,0.2);
    background: linear-gradient(45deg, #FF8E53, #FF6B6B);
}

.btn:active {
    transform: translateY(0);
}

.hidden {
    display: none !important;
}

.game-over h2 {
    font-size: 2em;
    margin-bottom: 15px;
    color: #FFD700;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.3);
}

/* Particle effects for background */
.sky-background::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image: 
        radial-gradient(2px 2px at 20px 30px, #fff, transparent),
        radial-gradient(2px 2px at 40px 70px, rgba(255,255,255,0.8), transparent),
        radial-gradient(1px 1px at 90px 40px, #fff, transparent),
        radial-gradient(1px 1px at 130px 80px, rgba(255,255,255,0.6), transparent),
        radial-gradient(2px 2px at 160px 30px, #fff, transparent);
    background-repeat: repeat;
    background-size: 200px 100px;
    animation: sparkle 20s linear infinite;
    opacity: 0.6;
}

@keyframes sparkle {
    from { transform: translateY(0); }
    to { transform: translateY(-100px); }
}

/* Responsive design */
@media (max-width: 900px) {
    #gameCanvas {
        width: 95vw;
        height: 70vh;
    }
    
    .start-screen, .game-over {
        max-width: 90vw;
        padding: 30px 20px;
    }
    
    .start-screen h1 {
        font-size: 2em;
    }
    
    .score-panel {
        font-size: 14px;
        padding: 10px;
    }
}

@media (max-width: 600px) {
    .controls {
        font-size: 12px;
        padding: 8px 15px;
    }
    
    .btn {
        padding: 12px 25px;
        font-size: 16px;
    }
}

/* Achievement notification styles */
.achievement-popup {
    position: fixed;
    top: 20px;
    right: 20px;
    background: linear-gradient(135deg, #FFD700 0%, #FFA500 100%);
    color: #333;
    padding: 15px 20px;
    border-radius: 10px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.3);
    z-index: 1000;
    animation: slideInAchievement 0.5s ease-out, fadeOutAchievement 0.5s ease-in 2.5s;
    max-width: 300px;
}

.achievement-content h3 {
    margin: 0 0 5px 0;
    font-size: 16px;
    font-weight: bold;
}

.achievement-content p {
    margin: 0;
    font-size: 14px;
}

@keyframes slideInAchievement {
    from {
        transform: translateX(100%);
        opacity: 0;
    }
    to {
        transform: translateX(0);
        opacity: 1;
    }
}

@keyframes fadeOutAchievement {
    from {
        opacity: 1;
    }
    to {
        opacity: 0;
    }
}