/* Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: #333;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
    background: rgba(255, 255, 255, 0.95);
    min-height: 100vh;
    box-shadow: 0 0 30px rgba(0, 0, 0, 0.1);
}

/* Header Styles */
header {
    text-align: center;
    margin-bottom: 2rem;
    padding: 2.5rem 0 1.5rem 0;
    background: linear-gradient(135deg, #232526 0%, #3498db 100%);
    color: #fff;
    border-radius: 16px 16px 0 0;
    box-shadow: 0 6px 24px rgba(44, 62, 80, 0.15);
    position: relative;
    z-index: 2;
}

header h1 {
    font-size: 2.8rem;
    font-weight: 600;
    letter-spacing: 2.5px;
    text-shadow: 0 4px 16px rgba(52, 152, 219, 0.25);
    margin-bottom: 0.5rem;
    font-family: 'Segoe UI', 'Montserrat', 'Arial', sans-serif;
}

/* Navigation Bar Styles */
.main-nav {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 2rem;
    background: linear-gradient(90deg, #3498db 0%, #764ba2 100%);
    padding: 1rem 0;
    border-radius: 0 0 16px 16px;
    box-shadow: 0 2px 12px rgba(52, 152, 219, 0.08);
    margin-bottom: 2rem;
    position: relative;
    z-index: 1;
}

.main-nav a {
    color: #fff;
    text-decoration: none;
    font-size: 1.15rem;
    font-weight: 500;
    padding: 0.5rem 1.2rem;
    border-radius: 8px;
    transition: background 0.3s, color 0.3s, box-shadow 0.3s;
    position: relative;
}

.main-nav a:hover,
.main-nav a:focus {
    background: rgba(255,255,255,0.12);
    color: #ffe082;
    box-shadow: 0 2px 8px rgba(52, 152, 219, 0.15);
}

.main-nav a.active {
    background: #fff;
    color: #3498db;
    font-weight: 700;
    box-shadow: 0 2px 8px rgba(52, 152, 219, 0.18);
}

/* Country Selector Styles */
.country-selector {
    margin: 2rem 0;
    padding: 1.5rem;
    background: #f8f9fa;
    border-radius: 10px;
    border-left: 4px solid #3498db;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
}

.country-selector label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 600;
    color: #2c3e50;
    font-size: 1.1rem;
}

.country-selector select {
    width: 100%;
    padding: 0.75rem;
    border: 2px solid #e1e8ed;
    border-radius: 5px;
    font-size: 1rem;
    background: white;
    color: #333;
    transition: all 0.3s ease;
}

.country-selector select:focus {
    outline: none;
    border-color: #3498db;
    box-shadow: 0 0 0 3px rgba(52, 152, 219, 0.1);
}

/* Calculator Section */
.calculator-section {
    margin: 2rem 0;
    padding: 2rem;
    background: white;
    border-radius: 15px;
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.1);
    border: 1px solid #e1e8ed;
}

.calculator-section h2 {
    color: #2c3e50;
    margin-bottom: 1.5rem;
    font-size: 1.8rem;
    font-weight: 600;
    text-align: center;
}

.calculator-form {
    display: grid;
    gap: 1.5rem;
}

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

.input-group label {
    margin-bottom: 0.5rem;
    font-weight: 600;
    color: #2c3e50;
    font-size: 1rem;
}

.input-group input {
    padding: 0.75rem;
    border: 2px solid #e1e8ed;
    border-radius: 5px;
    font-size: 1rem;
    transition: all 0.3s ease;
    background: #fafbfc;
}

.input-group input:focus {
    outline: none;
    border-color: #3498db;
    box-shadow: 0 0 0 3px rgba(52, 152, 219, 0.1);
    background: white;
}

.input-group input::placeholder {
    color: #95a5a6;
}

.calculate-btn {
    padding: 1rem 2rem;
    background: linear-gradient(135deg, #3498db 0%, #2980b9 100%);
    color: white;
    border: none;
    border-radius: 5px;
    font-size: 1.1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    margin-top: 1rem;
    box-shadow: 0 3px 10px rgba(52, 152, 219, 0.3);
}

.calculate-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(52, 152, 219, 0.4);
}

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

/* Result Section */
.result-section {
    margin-top: 1.5rem;
    padding: 1.5rem;
    background: linear-gradient(135deg, #27ae60 0%, #2ecc71 100%);
    color: white;
    border-radius: 10px;
    display: none;
    box-shadow: 0 3px 15px rgba(39, 174, 96, 0.3);
}

.result-section.show {
    display: block;
    animation: slideIn 0.5s ease;
}

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

/* CTA Section */
.cta-section {
    margin: 2rem 0;
    text-align: center;
    padding: 2rem;
    background: linear-gradient(135deg, #f39c12 0%, #e67e22 100%);
    border-radius: 15px;
    box-shadow: 0 5px 20px rgba(243, 156, 18, 0.3);
}

.cta-button {
    display: inline-block;
    padding: 1rem 2.5rem;
    background: white;
    color: #e67e22;
    text-decoration: none;
    border-radius: 50px;
    font-weight: 700;
    font-size: 1.2rem;
    transition: all 0.3s ease;
    box-shadow: 0 3px 15px rgba(0, 0, 0, 0.1);
    border: 3px solid transparent;
}

.cta-button:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.2);
    border-color: white;
    background: transparent;
    color: white;
}

/* Content Article */
.content-article {
    margin: 3rem 0;
    padding: 2rem;
    background: white;
    border-radius: 15px;
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.1);
    line-height: 1.8;
}

.content-article h2 {
    color: #2c3e50;
    margin-bottom: 1.5rem;
    font-size: 1.8rem;
    font-weight: 600;
    border-bottom: 3px solid #3498db;
    padding-bottom: 0.5rem;
}

.content-article h3 {
    color: #34495e;
    margin: 1.5rem 0 1rem;
    font-size: 1.4rem;
    font-weight: 600;
}

.content-article p {
    margin-bottom: 1rem;
    color: #555;
    text-align: justify;
}

/* Responsive Design */
@media (max-width: 768px) {
    .container {
        padding: 10px;
    }
    
    header h1 {
        font-size: 2rem;
    }
    
    .calculator-section,
    .content-article {
        padding: 1.5rem;
        margin: 1rem 0;
    }
    
    .input-group {
        margin-bottom: 1rem;
    }
    
    .cta-button {
        padding: 0.8rem 2rem;
        font-size: 1rem;
    }
}

@media (max-width: 480px) {
    header {
        padding: 1rem 0;
    }
    
    header h1 {
        font-size: 1.5rem;
        letter-spacing: 1px;
    }
    
    .calculator-section,
    .content-article,
    .cta-section {
        padding: 1rem;
    }
    
    .country-selector {
        padding: 1rem;
    }
}