* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

body {
    background-color: #f5f7fa;
    color: #333;
    line-height: 1.6;
}

.container {
    max-width: 900px;
    margin: 0 auto;
    padding: 30px 20px;
}

header {
    text-align: center;
    margin-bottom: 40px;
}

header h1 {
    color: #2c3e50;
    margin-bottom: 10px;
    font-size: 2.5rem;
}

header p {
    color: #7f8c8d;
    font-size: 1.1rem;
}

.converter-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
    background-color: #fff;
    padding: 25px;
    border-radius: 10px;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
}

.input-group {
    flex: 1;
    display: flex;
    flex-direction: column;
}

.input-group input {
    padding: 15px;
    border: 1px solid #ddd;
    border-radius: 5px;
    font-size: 1.2rem;
    margin-bottom: 10px;
    width: 100%;
}

.input-group select {
    padding: 12px;
    border: 1px solid #ddd;
    border-radius: 5px;
    font-size: 1rem;
    background-color: #f9f9f9;
    cursor: pointer;
}

.swap-button {
    margin: 0 20px;
}

.swap-button button {
    background-color: #3498db;
    color: white;
    border: none;
    width: 40px;
    height: 40px;
    border-radius: 50%;
    cursor: pointer;
    font-size: 1.2rem;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: background-color 0.3s;
}

.swap-button button:hover {
    background-color: #2980b9;
}

#convert-btn {
    display: block;
    width: 100%;
    padding: 15px;
    background-color: #2ecc71;
    color: white;
    border: none;
    border-radius: 5px;
    font-size: 1.1rem;
    cursor: pointer;
    transition: background-color 0.3s;
    margin-bottom: 20px;
}

#convert-btn:hover {
    background-color: #27ae60;
}

.info-container {
    background-color: #fff;
    padding: 15px 20px;
    border-radius: 8px;
    margin-bottom: 30px;
    display: flex;
    justify-content: space-between;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
}

.popular-rates {
    background-color: #fff;
    padding: 25px;
    border-radius: 10px;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
}

.popular-rates h3 {
    margin-bottom: 20px;
    color: #2c3e50;
    text-align: center;
}

.rates-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: 15px;
}

.rate-card {
    background-color: #f8f9fa;
    padding: 15px;
    border-radius: 8px;
    text-align: center;
    transition: transform 0.3s, box-shadow 0.3s;
}

.rate-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.1);
}

.rate-card .currency-pair {
    font-weight: bold;
    margin-bottom: 8px;
    color: #2c3e50;
}

.rate-card .rate-value {
    font-size: 1.2rem;
    color: #3498db;
}

footer {
    text-align: center;
    padding: 20px;
    margin-top: 40px;
    color: #7f8c8d;
    font-size: 0.9rem;
}

footer a {
    color: #3498db;
    text-decoration: none;
}

footer a:hover {
    text-decoration: underline;
}

@media (max-width: 768px) {
    .converter-container {
        flex-direction: column;
    }
    
    .input-group {
        width: 100%;
        margin-bottom: 15px;
    }
    
    .swap-button {
        margin: 10px 0;
    }
    
    .info-container {
        flex-direction: column;
    }
    
    .info-container div {
        margin-bottom: 10px;
    }
}