/* CSS Variables for theming */
:root {
    --primary-color: #3b82f6;
    --primary-hover: #2563eb;
    --primary-light: #dbeafe;
    --secondary-color: #64748b;
    --secondary-hover: #475569;
    --background: #f8fafc;
    --surface: #ffffff;
    --surface-hover: #f1f5f9;
    --text-primary: #1e293b;
    --text-secondary: #64748b;
    --text-muted: #94a3b8;
    --border-color: #e2e8f0;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -2px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -4px rgba(0, 0, 0, 0.1);
    --radius-sm: 6px;
    --radius-md: 8px;
    --radius-lg: 12px;
    --transition: all 0.2s ease;

    /* Node colors by scheme */
    --node-fill: #3b82f6;
    --node-stroke: #1d4ed8;
    --node-text: #ffffff;
    --edge-color: #64748b;
}

/* Color Schemes */
[data-theme="forest"] {
    --node-fill: #22c55e;
    --node-stroke: #15803d;
    --node-text: #ffffff;
    --edge-color: #4ade80;
}

[data-theme="sunset"] {
    --node-fill: #f97316;
    --node-stroke: #c2410c;
    --node-text: #ffffff;
    --edge-color: #fb923c;
}

[data-theme="purple"] {
    --node-fill: #8b5cf6;
    --node-stroke: #6d28d9;
    --node-text: #ffffff;
    --edge-color: #a78bfa;
}

[data-theme="monochrome"] {
    --node-fill: #475569;
    --node-stroke: #1e293b;
    --node-text: #ffffff;
    --edge-color: #94a3b8;
}

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

html {
    font-size: 16px;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    background: var(--background);
    color: var(--text-primary);
    line-height: 1.5;
    min-height: 100vh;
}

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

/* Header */
.header {
    background: var(--surface);
    border-bottom: 1px solid var(--border-color);
    padding: 1rem 1.5rem;
    text-align: center;
}

.logo {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.75rem;
}

.logo-icon {
    width: 32px;
    height: 32px;
    color: var(--primary-color);
}

.logo h1 {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-primary);
}

.tagline {
    font-size: 0.875rem;
    color: var(--text-secondary);
    margin-top: 0.25rem;
}

/* Main Content */
.main-content {
    display: flex;
    flex: 1;
    overflow: hidden;
}

/* Control Panel */
.control-panel {
    width: 320px;
    background: var(--surface);
    border-right: 1px solid var(--border-color);
    overflow-y: auto;
    padding: 1rem;
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.control-section {
    background: var(--surface);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: 1rem;
}

.control-section h2 {
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--text-secondary);
    margin-bottom: 0.75rem;
}

/* Select Wrapper */
.select-wrapper {
    position: relative;
}

.select-wrapper::after {
    content: '';
    position: absolute;
    right: 12px;
    top: 50%;
    transform: translateY(-50%);
    width: 0;
    height: 0;
    border-left: 5px solid transparent;
    border-right: 5px solid transparent;
    border-top: 5px solid var(--text-secondary);
    pointer-events: none;
}

select {
    width: 100%;
    padding: 0.625rem 2rem 0.625rem 0.75rem;
    font-size: 0.875rem;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    background: var(--surface);
    color: var(--text-primary);
    cursor: pointer;
    appearance: none;
    transition: var(--transition);
}

select:hover {
    border-color: var(--primary-color);
}

select:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px var(--primary-light);
}

/* Input Group */
.input-group {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

textarea {
    width: 100%;
    min-height: 80px;
    padding: 0.75rem;
    font-size: 0.875rem;
    font-family: 'Monaco', 'Menlo', 'Ubuntu Mono', monospace;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    background: var(--surface);
    color: var(--text-primary);
    resize: vertical;
    transition: var(--transition);
}

textarea:hover {
    border-color: var(--primary-color);
}

textarea:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px var(--primary-light);
}

textarea::placeholder {
    color: var(--text-muted);
}

.input-hint {
    font-size: 0.75rem;
    color: var(--text-muted);
}

/* Button Group */
.button-group {
    display: flex;
    gap: 0.5rem;
    margin-bottom: 0.5rem;
}

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

.btn {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    padding: 0.625rem 1rem;
    font-size: 0.875rem;
    font-weight: 500;
    border: none;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: var(--transition);
}

.btn svg {
    width: 16px;
    height: 16px;
}

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

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

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

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

.btn-outline {
    background: transparent;
    color: var(--primary-color);
    border: 1px solid var(--primary-color);
}

.btn-outline:hover {
    background: var(--primary-light);
}

/* Settings */
.setting-group {
    margin-bottom: 1rem;
}

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

.setting-group label {
    display: block;
    font-size: 0.8125rem;
    font-weight: 500;
    color: var(--text-primary);
    margin-bottom: 0.5rem;
}

.slider-container {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.slider-container span {
    min-width: 45px;
    font-size: 0.75rem;
    color: var(--text-secondary);
    text-align: right;
}

input[type="range"] {
    flex: 1;
    height: 6px;
    border-radius: 3px;
    background: var(--border-color);
    appearance: none;
    cursor: pointer;
}

input[type="range"]::-webkit-slider-thumb {
    appearance: none;
    width: 16px;
    height: 16px;
    border-radius: 50%;
    background: var(--primary-color);
    cursor: pointer;
    transition: var(--transition);
}

input[type="range"]::-webkit-slider-thumb:hover {
    transform: scale(1.1);
}

input[type="range"]::-moz-range-thumb {
    width: 16px;
    height: 16px;
    border: none;
    border-radius: 50%;
    background: var(--primary-color);
    cursor: pointer;
}

/* Checkbox */
.checkbox-group label {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    cursor: pointer;
    margin-bottom: 0;
}

.checkbox-group input[type="checkbox"] {
    width: 18px;
    height: 18px;
    border: 2px solid var(--border-color);
    border-radius: 4px;
    appearance: none;
    cursor: pointer;
    transition: var(--transition);
    position: relative;
}

.checkbox-group input[type="checkbox"]:checked {
    background: var(--primary-color);
    border-color: var(--primary-color);
}

.checkbox-group input[type="checkbox"]:checked::after {
    content: '';
    position: absolute;
    left: 5px;
    top: 2px;
    width: 4px;
    height: 8px;
    border: solid white;
    border-width: 0 2px 2px 0;
    transform: rotate(45deg);
}

/* Info Box */
.info-section {
    flex-shrink: 0;
}

.info-box {
    font-size: 0.8125rem;
    color: var(--text-secondary);
    line-height: 1.6;
}

.info-box strong {
    color: var(--text-primary);
}

.info-box ul {
    margin: 0.5rem 0;
    padding-left: 1.25rem;
}

.info-box li {
    margin-bottom: 0.25rem;
}

/* Visualization Area */
.visualization-area {
    flex: 1;
    display: flex;
    flex-direction: column;
    background: var(--background);
    position: relative;
    overflow: hidden;
}

.canvas-container {
    flex: 1;
    position: relative;
    overflow: hidden;
}

#visualCanvas {
    display: block;
    width: 100%;
    height: 100%;
    cursor: grab;
}

#visualCanvas:active {
    cursor: grabbing;
}

/* Empty State */
.empty-state {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    text-align: center;
    color: var(--text-muted);
}

.empty-state svg {
    width: 80px;
    height: 80px;
    margin-bottom: 1rem;
    opacity: 0.5;
}

.empty-state h3 {
    font-size: 1.125rem;
    font-weight: 600;
    color: var(--text-secondary);
    margin-bottom: 0.5rem;
}

.empty-state p {
    font-size: 0.875rem;
}

.empty-state.hidden {
    display: none;
}

/* Canvas Controls */
.canvas-controls {
    position: absolute;
    bottom: 1rem;
    right: 1rem;
    display: flex;
    gap: 0.5rem;
    background: var(--surface);
    padding: 0.5rem;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
}

.icon-btn {
    width: 36px;
    height: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: transparent;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: var(--transition);
    color: var(--text-secondary);
}

.icon-btn:hover {
    background: var(--surface-hover);
    color: var(--primary-color);
    border-color: var(--primary-color);
}

.icon-btn svg {
    width: 18px;
    height: 18px;
}

/* Footer */
.footer {
    background: var(--surface);
    border-top: 1px solid var(--border-color);
    padding: 1rem;
    text-align: center;
}

.footer p {
    font-size: 0.875rem;
    color: var(--text-secondary);
}

.footer a {
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 500;
    transition: var(--transition);
}

.footer a:hover {
    color: var(--primary-hover);
    text-decoration: underline;
}

/* Responsive Design */
@media (max-width: 1024px) {
    .main-content {
        flex-direction: column;
    }

    .control-panel {
        width: 100%;
        max-height: 50vh;
        border-right: none;
        border-bottom: 1px solid var(--border-color);
        flex-direction: row;
        flex-wrap: wrap;
        gap: 0.75rem;
        padding: 0.75rem;
    }

    .control-section {
        flex: 1;
        min-width: 200px;
    }

    .info-section {
        display: none;
    }

    .visualization-area {
        min-height: 50vh;
    }
}

@media (max-width: 640px) {
    .header {
        padding: 0.75rem 1rem;
    }

    .logo h1 {
        font-size: 1.25rem;
    }

    .logo-icon {
        width: 28px;
        height: 28px;
    }

    .tagline {
        font-size: 0.75rem;
    }

    .control-panel {
        flex-direction: column;
        max-height: 40vh;
    }

    .control-section {
        min-width: 100%;
    }

    .button-group {
        flex-direction: column;
    }

    .canvas-controls {
        bottom: 0.5rem;
        right: 0.5rem;
        padding: 0.375rem;
    }

    .icon-btn {
        width: 32px;
        height: 32px;
    }

    .icon-btn svg {
        width: 16px;
        height: 16px;
    }
}

/* Animations */
@keyframes fadeIn {
    from {
        opacity: 0;
        transform: scale(0.95);
    }
    to {
        opacity: 1;
        transform: scale(1);
    }
}

@keyframes pulse {
    0%, 100% {
        transform: scale(1);
    }
    50% {
        transform: scale(1.05);
    }
}

.animate-in {
    animation: fadeIn 0.3s ease-out;
}

/* Scrollbar */
.control-panel::-webkit-scrollbar {
    width: 6px;
}

.control-panel::-webkit-scrollbar-track {
    background: transparent;
}

.control-panel::-webkit-scrollbar-thumb {
    background: var(--border-color);
    border-radius: 3px;
}

.control-panel::-webkit-scrollbar-thumb:hover {
    background: var(--text-muted);
}

/* Print Styles */
@media print {
    .control-panel,
    .canvas-controls,
    .footer {
        display: none;
    }

    .visualization-area {
        width: 100%;
        height: 100vh;
    }
}