:root {
    --primary-color: #2196F3;
    --success-color: #4CAF50;
    --warning-color: #FFC107;
    --danger-color: #F44336;
    --purple-color: #9C27B0;
    --white: #FFFFFF;
    --light-gray: #F5F5F5;
    --gray: #9E9E9E;
    --dark-gray: #424242;
    --black: #212121;
    --shadow: 0 2px 8px rgba(0,0,0,0.1);
    --shadow-hover: 0 4px 16px rgba(0,0,0,0.15);
    --border-radius: 12px;
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(135deg, var(--light-gray) 0%, #E3F2FD 100%);
    color: var(--black);
    line-height: 1.6;
    padding-bottom: 80px;
    min-height: 100vh;
}

.app-header {
    background: linear-gradient(135deg, var(--primary-color), #1976D2);
    color: var(--white);
    padding: 20px;
    text-align: center;
    box-shadow: var(--shadow);
    position: sticky;
    top: 0;
    z-index: 100;
}

.header-content h1 {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 4px;
}

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

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

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

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

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

.welcome-card {
    background: var(--white);
    border-radius: var(--border-radius);
    padding: 24px;
    margin-bottom: 20px;
    box-shadow: var(--shadow);
    text-align: center;
}

.welcome-card h2 {
    color: var(--primary-color);
    margin-bottom: 12px;
    font-size: 1.4rem;
}

.welcome-card p {
    color: var(--dark-gray);
    font-size: 1rem;
}

.quick-stats {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 16px;
    margin-bottom: 24px;
}

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

.stat-card:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-hover);
}

.stat-card i {
    font-size: 2rem;
    color: var(--primary-color);
    margin-bottom: 12px;
}

.stat-number {
    display: block;
    font-size: 1.8rem;
    font-weight: 700;
    color: var(--black);
    margin-bottom: 4px;
}

.stat-label {
    font-size: 0.9rem;
    color: var(--gray);
}

.action-buttons {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 16px 24px;
    border: none;
    border-radius: var(--border-radius);
    font-size: 1rem;
    font-weight: 500;
    text-decoration: none;
    cursor: pointer;
    transition: var(--transition);
    box-shadow: var(--shadow);
}

.btn:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-hover);
}

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

.btn-primary:hover {
    background: #1976D2;
}

.btn-secondary {
    background: var(--white);
    color: var(--primary-color);
    border: 2px solid var(--primary-color);
}

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

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

.btn-warning {
    background: var(--warning-color);
    color: var(--black);
}

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

.analysis-header,
.results-header,
.simulation-header,
.history-header {
    text-align: center;
    margin-bottom: 24px;
}

.analysis-header h2,
.results-header h2,
.simulation-header h2,
.history-header h2 {
    color: var(--primary-color);
    font-size: 1.4rem;
    margin-bottom: 8px;
}

.analysis-header p,
.simulation-header p {
    color: var(--dark-gray);
    font-size: 1rem;
}

.results-actions,
.history-actions {
    display: flex;
    gap: 12px;
    justify-content: center;
    margin-top: 16px;
}

.company-form {
    background: var(--white);
    border-radius: var(--border-radius);
    padding: 24px;
    box-shadow: var(--shadow);
}

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

.form-group label {
    display: flex;
    align-items: center;
    gap: 8px;
    font-weight: 500;
    color: var(--dark-gray);
    margin-bottom: 8px;
}

.form-group label i {
    color: var(--primary-color);
    width: 20px;
}

.form-group input,
.form-group select {
    width: 100%;
    padding: 14px 16px;
    border: 2px solid #E0E0E0;
    border-radius: 8px;
    font-size: 1rem;
    transition: var(--transition);
    background: var(--white);
}

.form-group input:focus,
.form-group select:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(33, 150, 243, 0.1);
}

.analysis-results {
    display: grid;
    gap: 20px;
}

.result-card {
    background: var(--white);
    border-radius: var(--border-radius);
    padding: 24px;
    box-shadow: var(--shadow);
}

.result-card h3 {
    color: var(--primary-color);
    margin-bottom: 16px;
    font-size: 1.2rem;
}

.info-grid {
    display: grid;
    gap: 12px;
}

.info-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 12px 0;
    border-bottom: 1px solid #E0E0E0;
}

.info-item:last-child {
    border-bottom: none;
}

.info-label {
    font-weight: 500;
    color: var(--dark-gray);
}

.info-value {
    font-weight: 600;
    color: var(--black);
}

.analysis-content,
.impact-content,
.recommendations-content {
    line-height: 1.6;
}

.status-badge {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 6px 12px;
    border-radius: 20px;
    font-size: 0.85rem;
    font-weight: 500;
    margin: 4px 0;
}

.status-optimal {
    background: rgba(76, 175, 80, 0.1);
    color: var(--success-color);
}

.status-warning {
    background: rgba(255, 193, 7, 0.1);
    color: #F57C00;
}

.status-critical {
    background: rgba(244, 67, 54, 0.1);
    color: var(--danger-color);
}

.recommendation-item {
    background: var(--light-gray);
    border-radius: 8px;
    padding: 16px;
    margin-bottom: 12px;
    border-left: 4px solid var(--primary-color);
}

.recommendation-item h4 {
    color: var(--primary-color);
    margin-bottom: 8px;
    font-size: 1rem;
}

.simulation-controls {
    background: var(--white);
    border-radius: var(--border-radius);
    padding: 24px;
    margin-bottom: 24px;
    box-shadow: var(--shadow);
}

.simulation-results {
    display: grid;
    gap: 20px;
}

.simulation-card {
    background: var(--white);
    border-radius: var(--border-radius);
    padding: 24px;
    box-shadow: var(--shadow);
}

.simulation-summary {
    background: var(--white);
    border-radius: var(--border-radius);
    padding: 24px;
    box-shadow: var(--shadow);
}

.summary-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 12px 0;
    border-bottom: 1px solid #E0E0E0;
}

.summary-item:last-child {
    border-bottom: none;
}

.summary-label {
    font-weight: 500;
    color: var(--dark-gray);
}

.summary-value {
    font-weight: 700;
    color: var(--primary-color);
    font-size: 1.1rem;
}

.history-list {
    display: grid;
    gap: 16px;
}

.history-item {
    background: var(--white);
    border-radius: var(--border-radius);
    padding: 20px;
    box-shadow: var(--shadow);
    transition: var(--transition);
}

.history-item:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-hover);
}

.history-header-info {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: 12px;
}

.history-company {
    font-weight: 600;
    color: var(--black);
    font-size: 1.1rem;
}

.history-date {
    font-size: 0.85rem;
    color: var(--gray);
}

.history-details {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 12px;
    margin-bottom: 16px;
}

.history-detail {
    font-size: 0.9rem;
}

.history-detail strong {
    color: var(--dark-gray);
}

.history-actions {
    display: flex;
    gap: 8px;
}

.btn-small {
    padding: 8px 16px;
    font-size: 0.85rem;
}

.empty-state {
    text-align: center;
    padding: 40px 20px;
    color: var(--gray);
}

.empty-state i {
    font-size: 3rem;
    margin-bottom: 16px;
    color: var(--gray);
}

.empty-state p {
    font-size: 1.1rem;
    margin-bottom: 20px;
}

.faq-section {
    background: var(--white);
    border-radius: var(--border-radius);
    padding: 24px;
    margin: 24px 0;
    box-shadow: var(--shadow);
}

.faq-section h2 {
    color: var(--primary-color);
    margin-bottom: 24px;
    text-align: center;
    font-size: 1.4rem;
}

.faq-container {
    display: grid;
    gap: 12px;
}

.faq-item {
    border: 1px solid #E0E0E0;
    border-radius: 8px;
    overflow: hidden;
}

.faq-question {
    width: 100%;
    padding: 16px 20px;
    background: var(--light-gray);
    border: none;
    text-align: left;
    font-size: 1rem;
    font-weight: 500;
    color: var(--black);
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    transition: var(--transition);
}

.faq-question:hover {
    background: #EEEEEE;
}

.faq-question[aria-expanded="true"] {
    background: var(--primary-color);
    color: var(--white);
}

.faq-icon {
    font-size: 1.2rem;
    font-weight: 700;
    transition: var(--transition);
}

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

.faq-answer {
    padding: 0 20px;
    max-height: 0;
    overflow: hidden;
    transition: all 0.3s ease-in-out;
}

.faq-answer:not([hidden]) {
    padding: 20px;
    max-height: 200px;
}

.faq-answer p {
    color: var(--dark-gray);
    line-height: 1.6;
}

.bottom-nav {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    background: var(--white);
    border-top: 1px solid #E0E0E0;
    display: flex;
    justify-content: space-around;
    padding: 8px 0;
    box-shadow: 0 -2px 8px rgba(0,0,0,0.1);
    z-index: 1000;
}

.nav-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 4px;
    padding: 8px 12px;
    text-decoration: none;
    color: var(--gray);
    transition: var(--transition);
    border-radius: 8px;
    min-width: 60px;
}

.nav-item.active {
    color: var(--primary-color);
    background: rgba(33, 150, 243, 0.1);
}

.nav-item i {
    font-size: 1.2rem;
}

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

footer {
    text-align: center;
    padding: 20px;
    color: var(--gray);
    font-size: 0.85rem;
    margin-top: 40px;
    background: var(--white);
    border-top: 1px solid #E0E0E0;
}

.alert {
    padding: 16px;
    border-radius: 8px;
    margin-bottom: 16px;
    display: flex;
    align-items: center;
    gap: 12px;
}

.alert-success {
    background: rgba(76, 175, 80, 0.1);
    border-left: 4px solid var(--success-color);
    color: var(--success-color);
}

.alert-warning {
    background: rgba(255, 193, 7, 0.1);
    border-left: 4px solid var(--warning-color);
    color: #F57C00;
}

.alert-danger {
    background: rgba(244, 67, 54, 0.1);
    border-left: 4px solid var(--danger-color);
    color: var(--danger-color);
}

.loading {
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 40px;
}

.spinner {
    width: 40px;
    height: 40px;
    border: 4px solid #E0E0E0;
    border-top: 4px solid var(--primary-color);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

@media (min-width: 768px) {
    .app-main {
        padding: 32px;
    }
    
    .quick-stats {
        grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    }
    
    .action-buttons {
        flex-direction: row;
        justify-content: center;
    }
    
    .results-actions,
    .history-actions {
        flex-direction: row;
    }
    
    .analysis-results {
        grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    }
    
    .simulation-results {
        grid-template-columns: 2fr 1fr;
    }
    
    .history-details {
        grid-template-columns: repeat(3, 1fr);
    }
    
    .bottom-nav {
        max-width: 600px;
        left: 50%;
        transform: translateX(-50%);
        border-radius: var(--border-radius) var(--border-radius) 0 0;
    }
}

@media (min-width: 1024px) {
    .header-content h1 {
        font-size: 2rem;
    }
    
    .header-content p {
        font-size: 1rem;
    }
    
    .analysis-results {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .faq-container {
        grid-template-columns: repeat(2, 1fr);
        gap: 20px;
    }
}

canvas {
    max-width: 100%;
    height: auto;
    border-radius: 8px;
}

.chart-container {
    position: relative;
    height: 300px;
    margin: 16px 0;
}

@media (max-width: 480px) {
    .app-main {
        padding: 16px;
    }
    
    .company-form,
    .simulation-controls {
        padding: 20px;
    }
    
    .result-card,
    .simulation-card {
        padding: 20px;
    }
    
    .history-details {
        grid-template-columns: 1fr;
    }
    
    .history-actions {
        flex-direction: column;
    }
    
    .btn {
        padding: 14px 20px;
        font-size: 0.95rem;
    }
}