/* CSS Variables */
:root {
    --primary-color: #6366F1;
    --primary-hover: #4F46E5;
    --secondary-color: #10B981;
    --accent-color: #FF6B6B;
    --background: #0F172A;
    --surface: #1E293B;
    --surface-hover: #334155;
    --border-color: #334155;
    --text-primary: #F8FAFC;
    --text-secondary: #94A3B8;
    --text-muted: #64748B;
    --success: #10B981;
    --warning: #F59E0B;
    --error: #EF4444;
    --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.3), 0 2px 4px -2px rgba(0, 0, 0, 0.2);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.3), 0 4px 6px -4px rgba(0, 0, 0, 0.2);
    --radius: 8px;
    --radius-lg: 12px;
    --transition: all 0.2s ease;
}

/* Reset & Base Styles */
*, *::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, sans-serif;
    background: var(--background);
    color: var(--text-primary);
    line-height: 1.6;
    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;
}

.header-content {
    max-width: 1400px;
    margin: 0 auto;
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 0.5rem;
}

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

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

.logo h1 {
    font-size: 1.5rem;
    font-weight: 700;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

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

/* Main Content */
.main-content {
    flex: 1;
    display: grid;
    grid-template-columns: 280px 1fr 300px;
    gap: 1.5rem;
    padding: 1.5rem;
    max-width: 1600px;
    margin: 0 auto;
    width: 100%;
}

/* Control Panel */
.controls-panel {
    background: var(--surface);
    border-radius: var(--radius-lg);
    padding: 1.25rem;
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
    height: fit-content;
    position: sticky;
    top: 1.5rem;
}

.control-group h3 {
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--text-secondary);
    margin-bottom: 0.75rem;
}

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

.mode-btn {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 0.75rem 1rem;
    background: var(--background);
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    color: var(--text-secondary);
    cursor: pointer;
    transition: var(--transition);
    font-size: 0.875rem;
}

.mode-btn svg {
    width: 20px;
    height: 20px;
    flex-shrink: 0;
}

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

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

/* Settings */
.setting-row {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    margin-bottom: 0.75rem;
}

.setting-row label {
    font-size: 0.875rem;
    color: var(--text-secondary);
    min-width: 60px;
}

.setting-row input[type="color"] {
    width: 36px;
    height: 36px;
    border: none;
    border-radius: var(--radius);
    cursor: pointer;
    background: none;
}

.setting-row input[type="color"]::-webkit-color-swatch-wrapper {
    padding: 2px;
}

.setting-row input[type="color"]::-webkit-color-swatch {
    border-radius: 4px;
    border: 2px solid var(--border-color);
}

.setting-row input[type="range"] {
    flex: 1;
    height: 4px;
    background: var(--background);
    border-radius: 2px;
    -webkit-appearance: none;
    cursor: pointer;
}

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

.setting-row input[type="range"]::-webkit-slider-thumb:hover {
    transform: scale(1.2);
}

.setting-row span {
    font-size: 0.75rem;
    color: var(--text-muted);
    min-width: 35px;
    text-align: right;
}

/* Action Buttons */
.action-buttons {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.action-btn {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.625rem 0.875rem;
    background: var(--background);
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    color: var(--text-secondary);
    cursor: pointer;
    transition: var(--transition);
    font-size: 0.8125rem;
}

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

.action-btn:hover {
    background: var(--surface-hover);
    color: var(--text-primary);
}

/* Canvas Section */
.canvas-section {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.canvas-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.canvas-header h2 {
    font-size: 1.125rem;
    font-weight: 600;
}

.canvas-info {
    display: flex;
    gap: 1.5rem;
    font-size: 0.8125rem;
    color: var(--text-muted);
    font-family: 'SF Mono', 'Monaco', 'Consolas', monospace;
}

.canvas-container {
    position: relative;
    background: var(--surface);
    border-radius: var(--radius-lg);
    overflow: hidden;
    min-height: 500px;
    flex: 1;
}

/* Ruler Overlays */
.ruler-overlay {
    position: absolute;
    background: var(--background);
    z-index: 10;
    display: none;
}

.ruler-overlay.visible {
    display: block;
}

.ruler-overlay.horizontal {
    top: 0;
    left: 30px;
    right: 0;
    height: 24px;
    border-bottom: 1px solid var(--border-color);
}

.ruler-overlay.vertical {
    left: 0;
    top: 24px;
    bottom: 0;
    width: 30px;
    border-right: 1px solid var(--border-color);
}

.ruler-tick {
    position: absolute;
    background: var(--text-muted);
}

.ruler-overlay.horizontal .ruler-tick {
    width: 1px;
    bottom: 0;
}

.ruler-overlay.horizontal .ruler-tick.major {
    height: 10px;
}

.ruler-overlay.horizontal .ruler-tick.minor {
    height: 5px;
}

.ruler-overlay.vertical .ruler-tick {
    height: 1px;
    right: 0;
}

.ruler-overlay.vertical .ruler-tick.major {
    width: 10px;
}

.ruler-overlay.vertical .ruler-tick.minor {
    width: 5px;
}

.ruler-label {
    position: absolute;
    font-size: 9px;
    color: var(--text-muted);
    font-family: 'SF Mono', 'Monaco', 'Consolas', monospace;
}

.ruler-overlay.horizontal .ruler-label {
    top: 2px;
}

.ruler-overlay.vertical .ruler-label {
    left: 2px;
    transform: rotate(-90deg);
    transform-origin: left top;
}

/* Measurement Canvas */
.measurement-canvas {
    position: relative;
    min-height: 500px;
    cursor: crosshair;
    background:
        linear-gradient(90deg, var(--border-color) 1px, transparent 1px),
        linear-gradient(var(--border-color) 1px, transparent 1px);
    background-size: 20px 20px;
    background-position: -1px -1px;
}

.canvas-placeholder {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    text-align: center;
    color: var(--text-muted);
    pointer-events: none;
}

.canvas-placeholder svg {
    width: 64px;
    height: 64px;
    margin-bottom: 1rem;
    opacity: 0.5;
}

.canvas-placeholder p {
    font-size: 1rem;
    margin-bottom: 0.25rem;
}

.canvas-placeholder span {
    font-size: 0.8125rem;
    opacity: 0.7;
}

.canvas-placeholder.hidden {
    display: none;
}

.canvas-image {
    display: none;
    max-width: 100%;
    max-height: 100%;
    object-fit: contain;
}

.canvas-image.visible {
    display: block;
}

/* Guides Layer */
.guides-layer {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    pointer-events: none;
}

.guide {
    position: absolute;
    pointer-events: auto;
    cursor: pointer;
}

.guide.horizontal {
    left: 0;
    right: 0;
    height: 1px;
}

.guide.vertical {
    top: 0;
    bottom: 0;
    width: 1px;
}

.guide-label {
    position: absolute;
    background: var(--surface);
    color: var(--text-primary);
    padding: 2px 6px;
    border-radius: 3px;
    font-size: 11px;
    font-family: 'SF Mono', 'Monaco', 'Consolas', monospace;
    white-space: nowrap;
    box-shadow: var(--shadow);
}

.guide.horizontal .guide-label {
    right: 8px;
    top: 4px;
}

.guide.vertical .guide-label {
    top: 8px;
    left: 4px;
}

/* Active Measurement */
.active-measurement {
    position: absolute;
    pointer-events: none;
    display: none;
}

.active-measurement.visible {
    display: block;
}

.active-measurement.horizontal {
    height: 2px;
    background: var(--accent-color);
}

.active-measurement.vertical {
    width: 2px;
    background: var(--accent-color);
}

.active-measurement.box {
    border: 2px solid var(--accent-color);
    background: rgba(255, 107, 107, 0.1);
}

.measurement-dimension {
    position: absolute;
    background: var(--accent-color);
    color: white;
    padding: 4px 8px;
    border-radius: 4px;
    font-size: 12px;
    font-weight: 600;
    font-family: 'SF Mono', 'Monaco', 'Consolas', monospace;
    white-space: nowrap;
    box-shadow: var(--shadow);
}

.active-measurement.horizontal .measurement-dimension {
    top: 8px;
    left: 50%;
    transform: translateX(-50%);
}

.active-measurement.vertical .measurement-dimension {
    left: 8px;
    top: 50%;
    transform: translateY(-50%);
}

.active-measurement.box .measurement-dimension {
    top: -28px;
    left: 50%;
    transform: translateX(-50%);
}

.active-measurement.box .measurement-dimension.height-label {
    top: 50%;
    left: calc(100% + 8px);
    transform: translateY(-50%) translateX(0);
}

/* Saved Measurement Markers */
.saved-measurement {
    position: absolute;
    pointer-events: auto;
    cursor: pointer;
    transition: var(--transition);
}

.saved-measurement:hover {
    opacity: 0.8;
}

.saved-measurement.horizontal {
    height: 2px;
}

.saved-measurement.vertical {
    width: 2px;
}

.saved-measurement.box {
    border: 2px solid;
    background: rgba(99, 102, 241, 0.1);
}

.saved-measurement .measurement-label {
    position: absolute;
    background: var(--surface);
    color: var(--text-primary);
    padding: 3px 8px;
    border-radius: 4px;
    font-size: 11px;
    font-family: 'SF Mono', 'Monaco', 'Consolas', monospace;
    white-space: nowrap;
    box-shadow: var(--shadow);
    border: 1px solid var(--border-color);
}

.saved-measurement.horizontal .measurement-label {
    top: 6px;
    left: 50%;
    transform: translateX(-50%);
}

.saved-measurement.vertical .measurement-label {
    left: 6px;
    top: 50%;
    transform: translateY(-50%);
}

.saved-measurement.box .measurement-label {
    top: -26px;
    left: 50%;
    transform: translateX(-50%);
}

/* Canvas Actions */
.canvas-actions {
    display: flex;
    gap: 0.75rem;
    flex-wrap: wrap;
}

.upload-btn {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.75rem 1.25rem;
    background: var(--primary-color);
    border: none;
    border-radius: var(--radius);
    color: white;
    font-size: 0.875rem;
    font-weight: 500;
    cursor: pointer;
    transition: var(--transition);
}

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

.upload-btn.secondary {
    background: var(--surface);
    border: 1px solid var(--border-color);
    color: var(--text-secondary);
}

.upload-btn.secondary:hover {
    background: var(--surface-hover);
    color: var(--text-primary);
}

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

/* Measurements Panel */
.measurements-panel {
    background: var(--surface);
    border-radius: var(--radius-lg);
    display: flex;
    flex-direction: column;
    height: fit-content;
    max-height: calc(100vh - 180px);
    position: sticky;
    top: 1.5rem;
}

.panel-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 1.25rem;
    border-bottom: 1px solid var(--border-color);
}

.panel-header h3 {
    font-size: 0.875rem;
    font-weight: 600;
}

.icon-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 32px;
    height: 32px;
    background: var(--background);
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    color: var(--text-secondary);
    cursor: pointer;
    transition: var(--transition);
}

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

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

.measurements-list {
    flex: 1;
    overflow-y: auto;
    padding: 0.75rem;
}

.empty-state {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 2rem 1rem;
    text-align: center;
    color: var(--text-muted);
}

.empty-state svg {
    width: 48px;
    height: 48px;
    margin-bottom: 1rem;
    opacity: 0.5;
}

.empty-state p {
    font-size: 0.875rem;
    margin-bottom: 0.25rem;
}

.empty-state span {
    font-size: 0.75rem;
    opacity: 0.7;
}

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

/* Measurement Card */
.measurement-card {
    background: var(--background);
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    padding: 0.875rem;
    margin-bottom: 0.5rem;
    transition: var(--transition);
}

.measurement-card:hover {
    border-color: var(--primary-color);
}

.measurement-card-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 0.5rem;
}

.measurement-type {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    color: var(--primary-color);
}

.measurement-type svg {
    width: 14px;
    height: 14px;
}

.measurement-delete {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 24px;
    height: 24px;
    background: transparent;
    border: none;
    border-radius: 4px;
    color: var(--text-muted);
    cursor: pointer;
    transition: var(--transition);
}

.measurement-delete:hover {
    background: var(--error);
    color: white;
}

.measurement-delete svg {
    width: 14px;
    height: 14px;
}

.measurement-values {
    display: flex;
    gap: 1rem;
    font-family: 'SF Mono', 'Monaco', 'Consolas', monospace;
    font-size: 0.9375rem;
    color: var(--text-primary);
}

.measurement-value {
    display: flex;
    align-items: center;
    gap: 0.25rem;
}

.measurement-value span {
    color: var(--text-muted);
    font-size: 0.75rem;
}

.measurement-position {
    font-size: 0.75rem;
    color: var(--text-muted);
    margin-top: 0.5rem;
}

/* Footer */
.footer {
    background: var(--surface);
    border-top: 1px solid var(--border-color);
    padding: 1rem 1.5rem;
    margin-top: auto;
}

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

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

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

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

/* Toast Notifications */
.toast-container {
    position: fixed;
    bottom: 1.5rem;
    right: 1.5rem;
    z-index: 1000;
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.toast {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 0.875rem 1.25rem;
    background: var(--surface);
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    box-shadow: var(--shadow-lg);
    animation: slideIn 0.3s ease;
}

.toast.success {
    border-color: var(--success);
}

.toast.error {
    border-color: var(--error);
}

.toast.warning {
    border-color: var(--warning);
}

.toast-icon {
    width: 20px;
    height: 20px;
    flex-shrink: 0;
}

.toast.success .toast-icon {
    color: var(--success);
}

.toast.error .toast-icon {
    color: var(--error);
}

.toast.warning .toast-icon {
    color: var(--warning);
}

.toast-message {
    font-size: 0.875rem;
    color: var(--text-primary);
}

@keyframes slideIn {
    from {
        opacity: 0;
        transform: translateX(100%);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

@keyframes slideOut {
    from {
        opacity: 1;
        transform: translateX(0);
    }
    to {
        opacity: 0;
        transform: translateX(100%);
    }
}

.toast.hiding {
    animation: slideOut 0.3s ease forwards;
}

/* Responsive Design */
@media (max-width: 1200px) {
    .main-content {
        grid-template-columns: 1fr;
        gap: 1rem;
    }

    .controls-panel,
    .measurements-panel {
        position: static;
        max-height: none;
    }

    .controls-panel {
        display: grid;
        grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
        gap: 1rem;
    }

    .control-group {
        margin-bottom: 0;
    }
}

@media (max-width: 768px) {
    .header-content {
        flex-direction: column;
        align-items: flex-start;
    }

    .main-content {
        padding: 1rem;
    }

    .controls-panel {
        grid-template-columns: 1fr;
    }

    .button-group {
        flex-direction: row;
        flex-wrap: wrap;
    }

    .mode-btn {
        flex: 1;
        min-width: 100px;
        justify-content: center;
    }

    .mode-btn span {
        display: none;
    }

    .canvas-info {
        flex-direction: column;
        gap: 0.25rem;
    }

    .canvas-actions {
        flex-direction: column;
    }

    .upload-btn {
        width: 100%;
        justify-content: center;
    }

    .measurements-list {
        max-height: 300px;
    }
}

@media (max-width: 480px) {
    .logo h1 {
        font-size: 1.25rem;
    }

    .canvas-container {
        min-height: 300px;
    }

    .measurement-canvas {
        min-height: 300px;
    }

    .toast-container {
        left: 1rem;
        right: 1rem;
        bottom: 1rem;
    }
}

/* Drag State */
.measurement-canvas.dragging {
    cursor: crosshair !important;
}

/* Custom Scrollbar */
.measurements-list::-webkit-scrollbar {
    width: 6px;
}

.measurements-list::-webkit-scrollbar-track {
    background: var(--background);
    border-radius: 3px;
}

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

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

/* Selection Prevention during drag */
.no-select {
    -webkit-user-select: none;
    -moz-user-select: none;
    -ms-user-select: none;
    user-select: none;
}

/* Drop Zone */
.canvas-container.drag-over {
    outline: 3px dashed var(--primary-color);
    outline-offset: -3px;
}

.canvas-container.drag-over .measurement-canvas {
    opacity: 0.7;
}