:root {
    --primary-color: #2c3e50;
    --secondary-color: #3498db;
    --background-color: #ecf0f1;
    --danger-color: #e74c3c;
    --success-color: #2ecc71;
    --text-color: #2c3e50;
    --border-radius: 12px;
    --shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    --transition: all 0.3s ease;
}

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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: var(--background-color);
    color: var(--text-color);
    line-height: 1.6;
    padding-bottom: 80px;
}

.app-header {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    padding: 20px;
    text-align: center;
    box-shadow: var(--shadow);
}

.app-header h1 {
    font-size: 1.8rem;
    margin-bottom: 5px;
}

.app-header p {
    opacity: 0.9;
    font-size: 0.9rem;
}

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

.app-section {
    display: none;
    animation: fadeIn 0.3s ease-in;
}

.app-section.active {
    display: block;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

.welcome-card {
    background: white;
    border-radius: var(--border-radius);
    padding: 25px;
    margin-bottom: 20px;
    box-shadow: var(--shadow);
    text-align: center;
}

.welcome-card h2 {
    color: var(--primary-color);
    margin-bottom: 10px;
    font-size: 1.5rem;
}

.quick-stats {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
    gap: 15px;
    margin-top: 20px;
}

.stat-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 15px;
    background: var(--background-color);
    border-radius: var(--border-radius);
}

.stat-item i {
    font-size: 1.5rem;
    color: var(--secondary-color);
    margin-bottom: 8px;
}

.stat-number {
    font-size: 1.2rem;
    font-weight: bold;
    color: var(--primary-color);
}

.stat-label {
    font-size: 0.8rem;
    color: #666;
    text-align: center;
}

.action-cards {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 15px;
}

.action-card {
    background: white;
    border-radius: var(--border-radius);
    padding: 20px;
    text-align: center;
    cursor: pointer;
    transition: var(--transition);
    box-shadow: var(--shadow);
}

.action-card:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 12px rgba(0, 0, 0, 0.15);
}

.action-card i {
    font-size: 2rem;
    color: var(--secondary-color);
    margin-bottom: 10px;
}

.action-card h3 {
    color: var(--primary-color);
    margin-bottom: 8px;
}

.calculator-container,
.projects-container,
.incentives-container,
.faq-container {
    background: white;
    border-radius: var(--border-radius);
    padding: 25px;
    box-shadow: var(--shadow);
}

.energy-form {
    max-width: 500px;
    margin: 0 auto;
}

.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    margin-bottom: 5px;
    font-weight: 600;
    color: var(--primary-color);
}

.form-group input,
.form-group select {
    width: 100%;
    padding: 12px;
    border: 2px solid #ddd;
    border-radius: var(--border-radius);
    font-size: 1rem;
    transition: var(--transition);
}

.form-group input:focus,
.form-group select:focus {
    outline: none;
    border-color: var(--secondary-color);
    box-shadow: 0 0 0 3px rgba(52, 152, 219, 0.1);
}

.btn-primary,
.btn-secondary {
    width: 100%;
    padding: 15px;
    border: none;
    border-radius: var(--border-radius);
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
}

.btn-primary {
    background: var(--secondary-color);
    color: white;
}

.btn-primary:hover {
    background: #2980b9;
    transform: translateY(-1px);
}

.btn-secondary {
    background: var(--success-color);
    color: white;
    margin-top: 20px;
}

.btn-secondary:hover {
    background: #27ae60;
}

.error-message {
    background: #fdf2f2;
    color: var(--danger-color);
    padding: 10px;
    border-radius: var(--border-radius);
    margin-bottom: 15px;
    display: none;
    border-left: 4px solid var(--danger-color);
}

.results-container {
    margin-top: 30px;
    padding-top: 20px;
    border-top: 2px solid var(--background-color);
}

.results-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 15px;
    margin-bottom: 20px;
}

.result-card {
    background: var(--background-color);
    padding: 20px;
    border-radius: var(--border-radius);
    text-align: center;
}

.result-card h4 {
    color: var(--primary-color);
    margin-bottom: 10px;
    font-size: 0.9rem;
}

.result-value {
    font-size: 1.5rem;
    font-weight: bold;
    color: var(--secondary-color);
    margin-bottom: 5px;
}

.result-unit {
    font-size: 0.8rem;
    color: #666;
}

.financing-options {
    background: #f8f9fa;
    padding: 20px;
    border-radius: var(--border-radius);
    margin-top: 20px;
}

.financing-details {
    margin-top: 15px;
}

.financing-option {
    background: white;
    padding: 15px;
    border-radius: 8px;
    margin-bottom: 10px;
    border-left: 4px solid var(--success-color);
}

.projects-list {
    margin-top: 20px;
}

.empty-state {
    text-align: center;
    padding: 40px 20px;
    color: #666;
}

.empty-state i {
    font-size: 3rem;
    margin-bottom: 15px;
    opacity: 0.5;
}

.project-card {
    background: var(--background-color);
    border-radius: var(--border-radius);
    padding: 20px;
    margin-bottom: 15px;
    position: relative;
}

.project-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 15px;
}

.project-name {
    font-size: 1.2rem;
    font-weight: bold;
    color: var(--primary-color);
}

.project-date {
    font-size: 0.8rem;
    color: #666;
}

.project-details {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    gap: 10px;
}

.project-detail {
    text-align: center;
}

.project-detail-value {
    font-weight: bold;
    color: var(--secondary-color);
}

.project-detail-label {
    font-size: 0.8rem;
    color: #666;
}

.project-actions {
    position: absolute;
    top: 15px;
    right: 15px;
}

.btn-icon {
    background: none;
    border: none;
    color: #666;
    cursor: pointer;
    padding: 5px;
    margin-left: 5px;
    border-radius: 4px;
    transition: var(--transition);
}

.btn-icon:hover {
    background: #f0f0f0;
    color: var(--primary-color);
}

.btn-icon.delete:hover {
    color: var(--danger-color);
}

.incentives-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 20px;
    margin-bottom: 30px;
}

.incentive-card {
    background: var(--background-color);
    border-radius: var(--border-radius);
    padding: 20px;
    border-left: 4px solid var(--success-color);
}

.incentive-card h3 {
    color: var(--primary-color);
    margin-bottom: 10px;
    font-size: 1.1rem;
}

.incentive-details {
    margin-top: 15px;
}

.incentive-benefit {
    background: var(--success-color);
    color: white;
    padding: 5px 10px;
    border-radius: 15px;
    font-size: 0.8rem;
    font-weight: 600;
}

.incentive-finder {
    background: #f8f9fa;
    padding: 20px;
    border-radius: var(--border-radius);
    margin-top: 20px;
}

.state-incentives {
    margin-top: 15px;
}

.state-incentive {
    background: white;
    padding: 15px;
    border-radius: 8px;
    margin-bottom: 10px;
    border-left: 4px solid var(--secondary-color);
}

.faq-item {
    border-bottom: 1px solid #eee;
    margin-bottom: 10px;
}

.faq-question {
    width: 100%;
    background: none;
    border: none;
    padding: 20px 0;
    text-align: left;
    font-size: 1rem;
    font-weight: 600;
    color: var(--primary-color);
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    transition: var(--transition);
}

.faq-question:hover {
    color: var(--secondary-color);
}

.faq-icon {
    font-size: 1.2rem;
    transition: var(--transition);
}

.faq-question[aria-expanded="true"] .faq-icon {
    transform: rotate(45deg);
}

.faq-answer {
    padding: 0 0 20px 0;
    color: #666;
    line-height: 1.6;
    animation: slideDown 0.3s ease-out;
}

@keyframes slideDown {
    from {
        opacity: 0;
        max-height: 0;
    }
    to {
        opacity: 1;
        max-height: 200px;
    }
}

.bottom-nav {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    background: white;
    display: flex;
    justify-content: space-around;
    padding: 10px 0;
    box-shadow: 0 -2px 10px rgba(0, 0, 0, 0.1);
    z-index: 1000;
}

.nav-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-decoration: none;
    color: #666;
    transition: var(--transition);
    padding: 5px 10px;
    border-radius: 8px;
    min-width: 60px;
}

.nav-item.active,
.nav-item:hover {
    color: var(--secondary-color);
    background: rgba(52, 152, 219, 0.1);
}

.nav-item i {
    font-size: 1.2rem;
    margin-bottom: 2px;
}

.nav-item span {
    font-size: 0.7rem;
    font-weight: 500;
}

footer {
    background: var(--primary-color);
    color: white;
    text-align: center;
    padding: 15px;
    font-size: 0.8rem;
    margin-top: 40px;
}

@media (max-width: 768px) {
    .app-main {
        padding: 15px;
    }
    
    .app-header h1 {
        font-size: 1.5rem;
    }
    
    .welcome-card {
        padding: 20px;
    }
    
    .quick-stats {
        grid-template-columns: repeat(3, 1fr);
        gap: 10px;
    }
    
    .stat-item {
        padding: 10px;
    }
    
    .action-cards {
        grid-template-columns: 1fr;
    }
    
    .results-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 10px;
    }
    
    .result-card {
        padding: 15px;
    }
    
    .result-value {
        font-size: 1.2rem;
    }
    
    .incentives-grid {
        grid-template-columns: 1fr;
    }
    
    .project-details {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 480px) {
    .quick-stats {
        grid-template-columns: 1fr;
    }
    
    .results-grid {
        grid-template-columns: 1fr;
    }
    
    .project-details {
        grid-template-columns: 1fr;
    }
    
    .nav-item span {
        font-size: 0.6rem;
    }
}