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

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

.app-container {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

/* Header Styles */
.app-header {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid rgba(255, 255, 255, 0.2);
    padding: 1rem 2rem;
    box-shadow: 0 2px 20px rgba(0, 0, 0, 0.1);
}

.header-content h1 {
    font-size: 2.5rem;
    color: #4a5568;
    margin-bottom: 0.5rem;
    display: flex;
    align-items: center;
    gap: 1rem;
}

.header-content h1 i {
    color: #667eea;
}

.header-content p {
    color: #718096;
    font-size: 1.1rem;
}

/* Navigation Styles */
.main-nav {
    background: rgba(255, 255, 255, 0.9);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid rgba(255, 255, 255, 0.2);
    padding: 0 2rem;
}

.nav-tabs {
    display: flex;
    gap: 0;
}

.nav-tab {
    background: none;
    border: none;
    padding: 1rem 2rem;
    cursor: pointer;
    font-size: 1rem;
    color: #718096;
    border-bottom: 3px solid transparent;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.nav-tab:hover {
    color: #4a5568;
    background: rgba(102, 126, 234, 0.1);
}

.nav-tab.active {
    color: #667eea;
    border-bottom-color: #667eea;
    background: rgba(102, 126, 234, 0.1);
}

/* Main Content */
.main-content {
    flex: 1;
    padding: 2rem;
}

.content-section {
    display: none;
}

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

.section-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 2rem;
    background: rgba(255, 255, 255, 0.9);
    padding: 1.5rem;
    border-radius: 12px;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.1);
}

.section-header h2 {
    color: #4a5568;
    font-size: 1.8rem;
}

.action-buttons {
    display: flex;
    gap: 1rem;
}

/* Button Styles */
.btn {
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    font-size: 1rem;
    font-weight: 500;
    transition: all 0.3s ease;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    text-decoration: none;
}

.btn-primary {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(102, 126, 234, 0.3);
}

.btn-secondary {
    background: #e2e8f0;
    color: #4a5568;
}

.btn-secondary:hover {
    background: #cbd5e0;
    transform: translateY(-2px);
}

.btn-sm {
    padding: 0.5rem 1rem;
    font-size: 0.9rem;
}

/* Workspace Layout */
.workspace {
    display: grid;
    grid-template-columns: 300px 1fr;
    gap: 2rem;
    height: calc(100vh - 200px);
}

.sidebar {
    background: rgba(255, 255, 255, 0.9);
    border-radius: 12px;
    padding: 1.5rem;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.1);
    overflow-y: auto;
}

.sidebar-section {
    margin-bottom: 2rem;
}

.sidebar-section h3 {
    color: #4a5568;
    margin-bottom: 1rem;
    font-size: 1.2rem;
    border-bottom: 2px solid #e2e8f0;
    padding-bottom: 0.5rem;
}

/* Canvas Container */
.canvas-container {
    background: rgba(255, 255, 255, 0.9);
    border-radius: 12px;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.1);
    display: flex;
    flex-direction: column;
    overflow: hidden;
}

.canvas-header {
    padding: 1rem 1.5rem;
    border-bottom: 1px solid #e2e8f0;
    background: #f7fafc;
}

.canvas-controls {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.zoom-level {
    font-weight: 500;
    color: #4a5568;
    min-width: 50px;
    text-align: center;
}

.canvas {
    flex: 1;
    padding: 2rem;
    overflow: auto;
    background: #f7fafc;
    background-image: 
        radial-gradient(circle at 1px 1px, rgba(0,0,0,0.1) 1px, transparent 0);
    background-size: 20px 20px;
}

/* Responsive Design */
@media (max-width: 1024px) {
    .workspace {
        grid-template-columns: 250px 1fr;
    }
    
    .header-content h1 {
        font-size: 2rem;
    }
}

@media (max-width: 768px) {
    .workspace {
        grid-template-columns: 1fr;
        grid-template-rows: auto 1fr;
    }
    
    .sidebar {
        order: 2;
        height: 200px;
    }
    
    .canvas-container {
        order: 1;
    }
    
    .section-header {
        flex-direction: column;
        gap: 1rem;
        align-items: stretch;
    }
    
    .action-buttons {
        justify-content: center;
    }
    
    .nav-tabs {
        flex-wrap: wrap;
    }
    
    .nav-tab {
        flex: 1;
        min-width: 120px;
    }
}

@media (max-width: 480px) {
    .main-content {
        padding: 1rem;
    }
    
    .app-header {
        padding: 1rem;
    }
    
    .header-content h1 {
        font-size: 1.5rem;
    }
    
    .header-content p {
        font-size: 1rem;
    }
    
    .nav-tab {
        padding: 0.75rem 1rem;
        font-size: 0.9rem;
    }
}