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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(135deg, #1a2980, #26d0ce);
    color: #333;
    min-height: 100vh;
    line-height: 1.6;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
}

header {
    text-align: center;
    margin-bottom: 40px;
    padding: 30px;
    background: rgba(255, 255, 255, 0.95);
    border-radius: 20px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
    animation: fadeIn 1s ease-out;
}

header h1 {
    color: #1a2980;
    font-size: 2.8rem;
    margin-bottom: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 15px;
}

header h1 i {
    color: #26d0ce;
    font-size: 2.5rem;
}

.subtitle {
    color: #666;
    font-size: 1.2rem;
    font-weight: 300;
}

.content {
    display: flex;
    flex-direction: column;
    gap: 40px;
}

.earth-container {
    background: rgba(255, 255, 255, 0.95);
    border-radius: 20px;
    padding: 30px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
    animation: slideUp 1s ease-out;
}

#earthCanvas {
    width: 100%;
    height: 500px;
    border-radius: 15px;
    background: linear-gradient(135deg, #0f2027, #203a43, #2c5364);
    box-shadow: inset 0 0 20px rgba(0, 0, 0, 0.3);
}

.controls {
    margin-top: 25px;
    display: flex;
    flex-wrap: wrap;
    gap: 20px;
    align-items: center;
    justify-content: center;
}

.control-group {
    display: flex;
    align-items: center;
    gap: 15px;
    flex-wrap: wrap;
}

.btn {
    padding: 12px 25px;
    background: linear-gradient(135deg, #1a2980, #26d0ce);
    color: white;
    border: none;
    border-radius: 50px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    gap: 8px;
    box-shadow: 0 4px 15px rgba(26, 41, 128, 0.3);
}

.btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(26, 41, 128, 0.4);
}

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

.control-group label {
    font-weight: 600;
    color: #1a2980;
}

#speedSlider {
    width: 200px;
    height: 8px;
    -webkit-appearance: none;
    background: linear-gradient(to right, #1a2980, #26d0ce);
    border-radius: 4px;
    outline: none;
}

#speedSlider::-webkit-slider-thumb {
    -webkit-appearance: none;
    width: 22px;
    height: 22px;
    border-radius: 50%;
    background: white;
    border: 3px solid #1a2980;
    cursor: pointer;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.2);
}

#speedValue {
    font-weight: 600;
    color: #1a2980;
    min-width: 40px;
}

.instructions, .features {
    background: rgba(255, 255, 255, 0.95);
    border-radius: 20px;
    padding: 30px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
    animation: slideUp 1s ease-out 0.2s both;
}

.instructions h2, .features h2 {
    color: #1a2980;
    font-size: 2rem;
    margin-bottom: 25px;
    display: flex;
    align-items: center;
    gap: 10px;
}

.instruction-list {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.instruction-item {
    display: flex;
    align-items: center;
    gap: 20px;
    padding: 20px;
    background: linear-gradient(135deg, rgba(26, 41, 128, 0.05), rgba(38, 208, 206, 0.05));
    border-radius: 15px;
    transition: transform 0.3s ease;
}

.instruction-item:hover {
    transform: translateX(10px);
}

.instruction-item i {
    font-size: 2rem;
    color: #26d0ce;
    min-width: 60px;
    text-align: center;
}

.instruction-item h3 {
    color: #1a2980;
    margin-bottom: 5px;
}

.feature-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 25px;
    margin-top: 20px;
}

.feature-card {
    background: linear-gradient(135deg, rgba(26, 41, 128, 0.1), rgba(38, 208, 206, 0.1));
    padding: 25px;
    border-radius: 15px;
    text-align: center;
    transition: all 0.3s ease;
    border: 2px solid transparent;
}

.feature-card:hover {
    transform: translateY(-5px);
    border-color: #26d0ce;
    box-shadow: 0 10px 25px rgba(38, 208, 206, 0.2);
}

.feature-card i {
    font-size: 2.5rem;
    color: #1a2980;
    margin-bottom: 15px;
}

.feature-card h3 {
    color: #1a2980;
    margin-bottom: 10px;
}

.feature-card p {
    color: #666;
    font-size: 0.95rem;
}

footer {
    text-align: center;
    margin-top: 50px;
    padding: 20px;
    color: white;
    font-size: 0.9rem;
    opacity: 0.8;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(-20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes slideUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@media (max-width: 768px) {
    header h1 {
        font-size: 2rem;
        flex-direction: column;
        gap: 10px;
    }
    
    #earthCanvas {
        height: 400px;
    }
    
    .controls {
        flex-direction: column;
        align-items: stretch;
    }
    
    .control-group {
        justify-content: center;
    }
    
    .feature-grid {
        grid-template-columns: 1fr;
    }
    
    .instruction-item {
        flex-direction: column;
        text-align: center;
    }
    
    .instruction-item i {
        min-width: auto;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 10px;
    }
    
    header, .earth-container, .instructions, .features {
        padding: 20px;
    }
    
    #earthCanvas {
        height: 300px;
    }
    
    .btn {
        padding: 10px 20px;
        font-size: 0.9rem;
    }
}