:root {
    --primary-color: #0d6efd;
    --secondary-color: #6c757d;
    --success-color: #198754;
    --info-color: #0dcaf0;
    --warning-color: #ffc107;
    --danger-color: #dc3545;
    --light-color: #f8f9fa;
    --dark-color: #212529;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: #f8f9fa;
    color: #333;
}

.navbar-brand {
    font-weight: 700;
}

.nav-link.active {
    font-weight: 600;
    border-bottom: 2px solid var(--primary-color);
}

.hero-section {
    background: linear-gradient(rgba(13, 110, 253, 0.8), rgba(13, 110, 253, 0.6)), url('https://images.unsplash.com/photo-1551288049-bebda4e38f71?ixlib=rb-4.0.3&ixid=M3wxMjA3fDB8MHxwaG90by1wYWdlfHx8fGVufDB8fHx8fA%3D%3D&auto=format&fit=crop&w=1470&q=80') center/cover no-repeat;
    color: white;
    padding: 4rem 0;
    border-radius: 0 0 20px 20px;
    margin-bottom: 2rem;
}

.calculator-card {
    border-radius: 15px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
    overflow: hidden;
    transition: transform 0.3s ease;
}

.calculator-card:hover {
    transform: translateY(-5px);
}

.card-header {
    background-color: var(--primary-color);
    color: white;
    font-weight: 600;
    padding: 1rem 1.5rem;
}

.form-label {
    font-weight: 500;
}

.btn-calculate {
    background-color: var(--primary-color);
    border: none;
    padding: 0.75rem 2rem;
    font-weight: 600;
    border-radius: 50px;
    transition: all 0.3s ease;
}

.btn-calculate:hover {
    background-color: #0b5ed7;
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(13, 110, 253, 0.3);
}

.result-card {
    border-radius: 15px;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.08);
    background: white;
    padding: 1.5rem;
    margin-top: 1.5rem;
    border-left: 5px solid var(--primary-color);
}

.sigma-meter {
    height: 30px;
    background: linear-gradient(to right, var(--danger-color), var(--warning-color), var(--success-color));
    border-radius: 15px;
    position: relative;
    margin: 1.5rem 0;
}

.sigma-indicator {
    position: absolute;
    top: -10px;
    width: 20px;
    height: 50px;
    background-color: white;
    border: 3px solid var(--dark-color);
    border-radius: 10px;
    transform: translateX(-50%);
    transition: left 0.5s ease;
}

.chart-container {
    position: relative;
    height: 300px;
    width: 100%;
}

.info-section {
    background-color: white;
    border-radius: 15px;
    padding: 2rem;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.05);
    margin-bottom: 2rem;
}

.info-section h3 {
    color: var(--primary-color);
    margin-bottom: 1rem;
}

.faq-item {
    margin-bottom: 1.5rem;
    border-bottom: 1px solid #eee;
    padding-bottom: 1rem;
}

.faq-question {
    font-weight: 600;
    color: var(--primary-color);
    cursor: pointer;
}

.faq-answer {
    margin-top: 0.5rem;
    color: #555;
}

.social-icons a {
    font-size: 1.2rem;
    transition: color 0.3s ease;
}

.social-icons a:hover {
    color: var(--primary-color) !important;
}

footer a {
    text-decoration: none;
    transition: color 0.3s ease;
}

footer a:hover {
    color: white !important;
}

@media (max-width: 768px) {
    .hero-section {
        padding: 2rem 0;
    }
    
    .calculator-card {
        margin-bottom: 1.5rem;
    }
}