/* Variáveis CSS */
:root {
    /* Cores principais */
    --primary-color: #2c3e50;
    --secondary-color: #3498db;
    --accent-color: #e74c3c;
    --success-color: #27ae60;
    --warning-color: #f39c12;
    --danger-color: #e74c3c;
    
    /* Cores de diagramas */
    --normal-color: #3498db;
    --shear-color: #2ecc71;
    --moment-color: #e74c3c;
    --torsion-color: #9b59b6;
    --deformed-color: #f39c12;
    
    /* Cores de interface */
    --bg-primary: #f8f9fa;
    --bg-secondary: #ffffff;
    --bg-tertiary: #e9ecef;
    --text-primary: #212529;
    --text-secondary: #6c757d;
    --border-color: #dee2e6;
    
    /* Sombras */
    --shadow-sm: 0 2px 4px rgba(0,0,0,0.1);
    --shadow-md: 0 4px 8px rgba(0,0,0,0.12);
    --shadow-lg: 0 8px 16px rgba(0,0,0,0.15);
    
    /* Bordas */
    --border-radius-sm: 4px;
    --border-radius-md: 8px;
    --border-radius-lg: 12px;
    
    /* Espaçamentos */
    --spacing-xs: 4px;
    --spacing-sm: 8px;
    --spacing-md: 16px;
    --spacing-lg: 24px;
    --spacing-xl: 32px;
    
    /* Tipografia */
    --font-primary: 'Inter', sans-serif;
    --font-mono: 'Source Code Pro', monospace;
}

/* Reset e estilos base */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: var(--font-primary);
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    height: 100vh;
    overflow: hidden;
}

/* Tela de Boas-Vindas */
.welcome-screen {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    z-index: 1000;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: opacity 0.3s ease;
}

.welcome-screen.hidden {
    opacity: 0;
    pointer-events: none;
}

.welcome-container {
    width: 90%;
    max-width: 1200px;
    background: rgba(255, 255, 255, 0.95);
    border-radius: var(--border-radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow-lg);
    color: var(--text-primary);
}

.welcome-header {
    background: var(--primary-color);
    color: white;
    padding: var(--spacing-xl);
    text-align: center;
}

.welcome-header h1 {
    font-size: 2.5rem;
    margin-bottom: var(--spacing-sm);
}

.welcome-header .subtitle {
    font-size: 1.1rem;
    opacity: 0.9;
}

.welcome-content {
    padding: var(--spacing-xl);
}

.welcome-card {
    background: var(--bg-secondary);
    border-radius: var(--border-radius-md);
    padding: var(--spacing-lg);
    margin-bottom: var(--spacing-xl);
    box-shadow: var(--shadow-sm);
}

.feature-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: var(--spacing-lg);
    margin-top: var(--spacing-lg);
}

.feature {
    text-align: center;
    padding: var(--spacing-md);
}

.feature i {
    font-size: 2.5rem;
    color: var(--secondary-color);
    margin-bottom: var(--spacing-sm);
}

.structure-selector h3 {
    margin-bottom: var(--spacing-lg);
    color: var(--primary-color);
}

.structure-cards {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-xl);
}

.structure-card {
    background: var(--bg-secondary);
    border-radius: var(--border-radius-md);
    padding: var(--spacing-lg);
    text-align: center;
    transition: transform 0.2s, box-shadow 0.2s;
    cursor: pointer;
    border: 2px solid transparent;
}

.structure-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-md);
    border-color: var(--secondary-color);
}

.structure-card i {
    font-size: 3rem;
    color: var(--secondary-color);
    margin-bottom: var(--spacing-md);
}

.structure-card h4 {
    margin-bottom: var(--spacing-sm);
    color: var(--primary-color);
}

.structure-card p {
    color: var(--text-secondary);
    margin-bottom: var(--spacing-md);
    font-size: 0.9rem;
}

.btn-select {
    background: var(--secondary-color);
    color: white;
    border: none;
    padding: var(--spacing-sm) var(--spacing-lg);
    border-radius: var(--border-radius-sm);
    cursor: pointer;
    font-weight: 600;
    transition: background 0.2s;
}

.btn-select:hover {
    background: #2980b9;
}

.quick-start {
    text-align: center;
    padding: var(--spacing-lg);
}

.example-select {
    width: 100%;
    max-width: 400px;
    padding: var(--spacing-sm);
    border-radius: var(--border-radius-sm);
    border: 1px solid var(--border-color);
    font-family: var(--font-primary);
    margin-top: var(--spacing-sm);
}

.welcome-footer {
    padding: var(--spacing-lg);
    text-align: center;
    border-top: 1px solid var(--border-color);
}

.disclaimer {
    color: var(--text-secondary);
    font-size: 0.9rem;
    margin-bottom: var(--spacing-md);
}

/* Interface Principal */
.main-interface {
    display: flex;
    flex-direction: column;
    height: 100vh;
}

.app-header {
    background: var(--bg-secondary);
    padding: var(--spacing-md) var(--spacing-lg);
    display: flex;
    align-items: center;
    justify-content: space-between;
    border-bottom: 1px solid var(--border-color);
    box-shadow: var(--shadow-sm);
}

.header-left {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
}

.btn-icon {
    background: none;
    border: none;
    color: var(--text-secondary);
    font-size: 1.2rem;
    cursor: pointer;
    padding: var(--spacing-xs);
    border-radius: var(--border-radius-sm);
    transition: all 0.2s;
}

.btn-icon:hover {
    background: var(--bg-tertiary);
    color: var(--primary-color);
}

#structure-title {
    font-size: 1.5rem;
    color: var(--primary-color);
}

.structure-indicator {
    display: flex;
    gap: var(--spacing-sm);
    align-items: center;
}

#structure-type-indicator {
    background: var(--bg-tertiary);
    color: var(--text-secondary);
    padding: 2px 8px;
    border-radius: var(--border-radius-sm);
    font-size: 0.8rem;
    font-weight: 600;
    text-transform: uppercase;
}

.status-badge {
    padding: 2px 8px;
    border-radius: var(--border-radius-sm);
    font-size: 0.8rem;
    font-weight: 600;
    text-transform: uppercase;
}

.status-badge.isostatic {
    background: var(--success-color);
    color: white;
}

.status-badge.hypostatic {
    background: var(--warning-color);
    color: white;
}

.status-badge.hyperstatic {
    background: var(--danger-color);
    color: white;
}

.header-center {
    flex: 1;
    display: flex;
    justify-content: center;
}

.app-controls {
    display: flex;
    gap: var(--spacing-sm);
}

.btn-control {
    padding: var(--spacing-sm) var(--spacing-lg);
    border: none;
    border-radius: var(--border-radius-sm);
    cursor: pointer;
    font-weight: 600;
    transition: all 0.2s;
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
}

.btn-control:not(.btn-primary) {
    background: var(--bg-tertiary);
    color: var(--text-primary);
}

.btn-control:not(.btn-primary):hover {
    background: var(--border-color);
}

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

.btn-primary:hover {
    background: #2980b9;
}

.header-right {
    display: flex;
    gap: var(--spacing-sm);
}

/* Container Principal */
.main-container {
    display: flex;
    flex: 1;
    overflow: hidden;
}

/* Painéis Laterais */
.left-panel, .right-panel {
    width: 280px;
    background: var(--bg-secondary);
    border-right: 1px solid var(--border-color);
    overflow-y: auto;
    padding: var(--spacing-md);
}

.right-panel {
    border-right: none;
    border-left: 1px solid var(--border-color);
}

.panel-section {
    margin-bottom: var(--spacing-lg);
    padding-bottom: var(--spacing-md);
    border-bottom: 1px solid var(--border-color);
}

.panel-section:last-child {
    border-bottom: none;
}

.panel-section h3 {
    font-size: 0.9rem;
    text-transform: uppercase;
    color: var(--text-secondary);
    margin-bottom: var(--spacing-md);
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
}

/* Ferramentas */
.tool-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--spacing-sm);
}

.tool-btn {
    background: var(--bg-tertiary);
    border: 2px solid transparent;
    border-radius: var(--border-radius-sm);
    padding: var(--spacing-sm);
    cursor: pointer;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--spacing-xs);
    transition: all 0.2s;
}

.tool-btn:hover {
    background: var(--border-color);
}

.tool-btn.active {
    border-color: var(--secondary-color);
    background: #e3f2fd;
}

.tool-btn i {
    font-size: 1.2rem;
}

.tool-btn span {
    font-size: 0.8rem;
}

/* Vínculos */
.support-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--spacing-sm);
}

.support-btn {
    background: var(--bg-tertiary);
    border: 2px solid transparent;
    border-radius: var(--border-radius-sm);
    padding: var(--spacing-sm);
    cursor: pointer;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--spacing-xs);
    transition: all 0.2s;
}

.support-btn:hover {
    background: var(--border-color);
}

.support-icon {
    width: 40px;
    height: 40px;
    background-size: contain;
    background-repeat: no-repeat;
    background-position: center;
}

.support-icon.roller {
    background-image: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24"><path fill="%232c3e50" d="M12,2A10,10 0 0,1 22,12A10,10 0 0,1 12,22A10,10 0 0,1 2,12A10,10 0 0,1 12,2M12,4A8,8 0 0,0 4,12A8,8 0 0,0 12,20A8,8 0 0,0 20,12A8,8 0 0,0 12,4Z"/></svg>');
}

/* Cargas */
.load-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-md);
}

.load-btn {
    background: var(--bg-tertiary);
    border: 2px solid transparent;
    border-radius: var(--border-radius-sm);
    padding: var(--spacing-sm);
    cursor: pointer;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--spacing-xs);
    transition: all 0.2s;
}

.load-btn:hover {
    background: var(--border-color);
}

.load-btn i {
    font-size: 1.2rem;
}

.load-properties {
    background: var(--bg-tertiary);
    border-radius: var(--border-radius-sm);
    padding: var(--spacing-md);
}

.input-group {
    margin-bottom: var(--spacing-sm);
}

.input-group:last-child {
    margin-bottom: 0;
}

.input-group label {
    display: block;
    font-size: 0.8rem;
    color: var(--text-secondary);
    margin-bottom: 4px;
}

.input-group input {
    width: 100%;
    padding: 6px 8px;
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius-sm);
    font-family: var(--font-primary);
}

.input-group input[type="checkbox"] {
    width: auto;
}

/* Área Central */
.center-area {
    flex: 1;
    display: flex;
    flex-direction: column;
    padding: var(--spacing-md);
    gap: var(--spacing-md);
}

.canvas-container {
    flex: 1;
    position: relative;
    background: white;
    border-radius: var(--border-radius-md);
    overflow: hidden;
    box-shadow: var(--shadow-sm);
}

#structure-canvas {
    width: 100%;
    height: 100%;
    display: block;
}

.canvas-overlay {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    pointer-events: none;
}

.coordinate-display {
    position: absolute;
    bottom: 10px;
    left: 10px;
    background: rgba(0, 0, 0, 0.7);
    color: white;
    padding: 4px 8px;
    border-radius: var(--border-radius-sm);
    font-size: 0.8rem;
    font-family: var(--font-mono);
}

.selection-info {
    position: absolute;
    top: 10px;
    right: 10px;
    background: rgba(0, 0, 0, 0.7);
    color: white;
    padding: 4px 8px;
    border-radius: var(--border-radius-sm);
    font-size: 0.8rem;
}

.canvas-controls {
    position: absolute;
    top: 10px;
    right: 10px;
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.canvas-btn {
    width: 36px;
    height: 36px;
    background: white;
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius-sm);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: var(--shadow-sm);
}

.canvas-btn:hover {
    background: var(--bg-tertiary);
}

/* Controles de Diagramas */
.diagram-controls {
    background: var(--bg-secondary);
    border-radius: var(--border-radius-md);
    padding: var(--spacing-md);
    box-shadow: var(--shadow-sm);
}

.diagram-controls h3 {
    margin-bottom: var(--spacing-md);
    font-size: 0.9rem;
    text-transform: uppercase;
    color: var(--text-secondary);
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
}

.diagram-toggle {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-md);
}

.toggle-switch {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    cursor: pointer;
}

.toggle-switch input {
    display: none;
}

.toggle-slider {
    width: 36px;
    height: 20px;
    background: var(--bg-tertiary);
    border-radius: 10px;
    position: relative;
    transition: background 0.2s;
}

.toggle-slider::before {
    content: '';
    position: absolute;
    width: 16px;
    height: 16px;
    background: white;
    border-radius: 50%;
    top: 2px;
    left: 2px;
    transition: transform 0.2s;
}

input:checked + .toggle-slider {
    background: var(--color);
}

input:checked + .toggle-slider::before {
    transform: translateX(16px);
}

.toggle-label {
    font-size: 0.9rem;
}

/* Painel Direito - Abas */
.panel-tabs {
    display: flex;
    border-bottom: 1px solid var(--border-color);
    margin-bottom: var(--spacing-md);
}

.tab-btn {
    flex: 1;
    padding: var(--spacing-sm);
    background: none;
    border: none;
    border-bottom: 2px solid transparent;
    cursor: pointer;
    font-size: 0.9rem;
    color: var(--text-secondary);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-xs);
    transition: all 0.2s;
}

.tab-btn:hover {
    color: var(--primary-color);
}

.tab-btn.active {
    color: var(--secondary-color);
    border-bottom-color: var(--secondary-color);
}

.tab-content {
    display: none;
}

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

/* Resultados */
.results-section {
    margin-bottom: var(--spacing-lg);
}

.results-section h4 {
    font-size: 0.9rem;
    color: var(--text-secondary);
    margin-bottom: var(--spacing-sm);
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
}

.results-container {
    background: var(--bg-tertiary);
    border-radius: var(--border-radius-sm);
    padding: var(--spacing-md);
}

.placeholder {
    color: var(--text-secondary);
    font-style: italic;
    text-align: center;
}

.property-item {
    display: flex;
    justify-content: space-between;
    margin-bottom: var(--spacing-xs);
    font-size: 0.9rem;
}

.property-item:last-child {
    margin-bottom: 0;
}

.property-label {
    color: var(--text-secondary);
}

.property-value {
    font-weight: 600;
    font-family: var(--font-mono);
}

/* Tutorial */
.tutorial-section {
    margin-bottom: var(--spacing-lg);
}

.concept-card {
    background: var(--bg-tertiary);
    border-radius: var(--border-radius-sm);
    padding: var(--spacing-md);
}

.concept-card h5 {
    color: var(--primary-color);
    margin-bottom: var(--spacing-sm);
}

.equation {
    background: white;
    border-radius: var(--border-radius-sm);
    padding: var(--spacing-sm);
    font-family: var(--font-mono);
    text-align: center;
    margin-top: var(--spacing-sm);
}

.tutorial-steps {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}

.step {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.step-number {
    width: 24px;
    height: 24px;
    background: var(--secondary-color);
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.8rem;
    font-weight: 600;
}

.convention-card {
    background: var(--bg-tertiary);
    border-radius: var(--border-radius-sm);
    padding: var(--spacing-md);
}

.convention-item {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-sm);
}

.convention-item:last-child {
    margin-bottom: 0;
}

.convention-icon {
    width: 20px;
    height: 20px;
    border: 2px solid var(--success-color);
    border-radius: var(--border-radius-sm);
}

.convention-icon.positive-moment {
    border-color: var(--moment-color);
}

/* Barra de Status */
.status-bar {
    background: var(--bg-secondary);
    padding: var(--spacing-sm) var(--spacing-md);
    border-top: 1px solid var(--border-color);
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 0.8rem;
}

.status-left {
    flex: 1;
}

.status-message {
    color: var(--text-secondary);
}

.status-center {
    flex: 1;
    display: flex;
    justify-content: center;
}

.status-indicators {
    display: flex;
    gap: var(--spacing-lg);
}

.status-indicator {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
}

.status-right {
    flex: 1;
    text-align: right;
}

.version {
    color: var(--text-secondary);
}

/* Modal */
.modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
}

.modal.hidden {
    display: none;
}

.modal-content {
    background: white;
    border-radius: var(--border-radius-lg);
    width: 90%;
    max-width: 600px;
    max-height: 90vh;
    overflow: hidden;
    box-shadow: var(--shadow-lg);
}

.modal-header {
    padding: var(--spacing-lg);
    background: var(--primary-color);
    color: white;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.modal-close {
    background: none;
    border: none;
    color: white;
    font-size: 1.5rem;
    cursor: pointer;
}

.modal-body {
    padding: var(--spacing-lg);
    overflow-y: auto;
    max-height: 60vh;
}

.modal-footer {
    padding: var(--spacing-lg);
    border-top: 1px solid var(--border-color);
    display: flex;
    justify-content: flex-end;
    gap: var(--spacing-sm);
}

.btn-secondary {
    background: var(--bg-tertiary);
    color: var(--text-primary);
    border: none;
    padding: var(--spacing-sm) var(--spacing-lg);
    border-radius: var(--border-radius-sm);
    cursor: pointer;
    font-weight: 600;
    transition: background 0.2s;
}

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

.btn-text {
    background: none;
    border: none;
    color: var(--text-secondary);
    cursor: pointer;
    padding: var(--spacing-sm);
}

/* Classes Utilitárias */
.hidden {
    display: none !important;
}

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

.mt-1 { margin-top: var(--spacing-sm); }
.mt-2 { margin-top: var(--spacing-md); }
.mt-3 { margin-top: var(--spacing-lg); }

.mb-1 { margin-bottom: var(--spacing-sm); }
.mb-2 { margin-bottom: var(--spacing-md); }
.mb-3 { margin-bottom: var(--spacing-lg); }