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

:root {
    --primary-color: #6366f1;
    --primary-hover: #5558e3;
    --secondary-color: #64748b;
    --danger-color: #ef4444;
    --success-color: #10b981;
    --background: #ffffff;
    --surface: #f8fafc;
    --border: #e2e8f0;
    --text-primary: #1e293b;
    --text-secondary: #64748b;
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1);
    --radius: 8px;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    color: var(--text-primary);
    overflow-x: hidden;
}

.app-container {
    max-width: 1920px;
    margin: 0 auto;
    background: var(--background);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.header {
    background: var(--background);
    border-bottom: 1px solid var(--border);
    padding: 1rem 1.5rem;
    box-shadow: var(--shadow-sm);
    position: sticky;
    top: 0;
    z-index: 100;
}

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-color);
}

.logo svg {
    width: 32px;
    height: 32px;
}

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

.main-content {
    display: flex;
    flex: 1;
    overflow: hidden;
}

.sidebar {
    width: 320px;
    background: var(--surface);
    border-right: 1px solid var(--border);
    padding: 1.5rem;
    overflow-y: auto;
    flex-shrink: 0;
}

.workspace {
    flex: 1;
    display: flex;
    flex-direction: column;
    background: var(--background);
    position: relative;
}

.code-panel {
    width: 400px;
    background: var(--surface);
    border-left: 1px solid var(--border);
    display: flex;
    flex-direction: column;
    flex-shrink: 0;
}

.panel {
    background: var(--background);
    border-radius: var(--radius);
    padding: 1.25rem;
    margin-bottom: 1.5rem;
    box-shadow: var(--shadow-sm);
}

.panel-title {
    font-size: 1rem;
    font-weight: 600;
    margin-bottom: 1rem;
    color: var(--text-primary);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.panel-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 1.5rem;
    border-bottom: 1px solid var(--border);
}

.control-group {
    margin-bottom: 1.25rem;
}

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

.control-label {
    display: block;
    font-size: 0.875rem;
    font-weight: 500;
    margin-bottom: 0.5rem;
    color: var(--text-secondary);
}

.control-input,
.control-select {
    width: 100%;
    padding: 0.5rem 0.75rem;
    border: 1px solid var(--border);
    border-radius: calc(var(--radius) / 2);
    font-size: 0.875rem;
    background: var(--background);
    transition: all 0.2s;
}

.control-input:focus,
.control-select:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgb(99 102 241 / 0.1);
}

.input-group {
    display: flex;
    gap: 0.5rem;
}

.input-group .control-input {
    flex: 1;
}

.icon-btn {
    padding: 0.5rem 0.75rem;
    border: 1px solid var(--border);
    border-radius: calc(var(--radius) / 2);
    background: var(--background);
    cursor: pointer;
    transition: all 0.2s;
    font-size: 1rem;
    font-weight: 600;
}

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

.range-group {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.control-range {
    flex: 1;
    -webkit-appearance: none;
    appearance: none;
    height: 6px;
    border-radius: 3px;
    background: var(--border);
    outline: none;
}

.control-range::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 18px;
    height: 18px;
    border-radius: 50%;
    background: var(--primary-color);
    cursor: pointer;
    transition: all 0.2s;
}

.control-range::-webkit-slider-thumb:hover {
    transform: scale(1.2);
    box-shadow: 0 0 0 8px rgb(99 102 241 / 0.1);
}

.range-value {
    min-width: 48px;
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--text-secondary);
}

.template-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 0.75rem;
    margin-bottom: 1rem;
}

.template-btn {
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 0.75rem;
    border: 2px solid var(--border);
    border-radius: var(--radius);
    background: var(--background);
    cursor: pointer;
    transition: all 0.2s;
}

.template-btn:hover {
    border-color: var(--primary-color);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.template-icon {
    width: 60px;
    height: 40px;
    margin-bottom: 0.5rem;
    color: var(--primary-color);
}

.template-btn span {
    font-size: 0.75rem;
    font-weight: 500;
    color: var(--text-secondary);
}

.btn {
    padding: 0.625rem 1.25rem;
    border: none;
    border-radius: calc(var(--radius) / 2);
    font-size: 0.875rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
}

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

.btn-primary:hover {
    background: var(--primary-hover);
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

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

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

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

.btn-danger:hover {
    background: #dc2626;
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

.btn-icon {
    padding: 0.5rem;
    background: transparent;
    border: 1px solid var(--border);
}

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

.toolbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 1.5rem;
    background: var(--surface);
    border-bottom: 1px solid var(--border);
}

.toolbar-group {
    display: flex;
    gap: 0.5rem;
}

.grid-container-wrapper {
    flex: 1;
    padding: 2rem;
    overflow: auto;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(45deg, #f0f0f0 25%, transparent 25%, transparent 75%, #f0f0f0 75%, #f0f0f0),
                linear-gradient(45deg, #f0f0f0 25%, transparent 25%, transparent 75%, #f0f0f0 75%, #f0f0f0);
    background-size: 20px 20px;
    background-position: 0 0, 10px 10px;
}

.grid-container {
    display: grid;
    width: 100%;
    max-width: 800px;
    height: 500px;
    background: white;
    border: 2px dashed var(--border);
    border-radius: var(--radius);
    padding: 1rem;
    position: relative;
}

.grid-item {
    background: var(--primary-color);
    border-radius: calc(var(--radius) / 2);
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    cursor: move;
    transition: all 0.2s;
    user-select: none;
    overflow: hidden;
}

.grid-item:hover {
    transform: scale(0.98);
    box-shadow: var(--shadow-lg);
}

.grid-item.selected {
    outline: 3px solid var(--primary-color);
    outline-offset: 2px;
}

.grid-item.dragging {
    opacity: 0.5;
    cursor: grabbing;
}

.item-label {
    font-size: 1.5rem;
    font-weight: 700;
    color: white;
    pointer-events: none;
}

.resize-handle {
    position: absolute;
    background: var(--primary-color);
    opacity: 0;
    transition: opacity 0.2s;
}

.grid-item:hover .resize-handle {
    opacity: 0.5;
}

.resize-handle:hover {
    opacity: 1 !important;
}

.resize-handle-right {
    right: 0;
    top: 50%;
    transform: translateY(-50%);
    width: 8px;
    height: 40px;
    cursor: ew-resize;
    border-radius: 4px;
}

.resize-handle-bottom {
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 40px;
    height: 8px;
    cursor: ns-resize;
    border-radius: 4px;
}

.resize-handle-corner {
    right: 0;
    bottom: 0;
    width: 16px;
    height: 16px;
    cursor: nwse-resize;
    border-radius: 0 0 calc(var(--radius) / 2) 0;
}

.item-properties-panel {
    position: absolute;
    right: 1.5rem;
    top: 50%;
    transform: translateY(-50%);
    background: var(--background);
    border-radius: var(--radius);
    padding: 1.25rem;
    box-shadow: var(--shadow-lg);
    width: 280px;
    z-index: 10;
}

.code-tabs {
    display: flex;
    gap: 0.5rem;
}

.tab-btn {
    padding: 0.375rem 0.75rem;
    border: none;
    background: transparent;
    color: var(--text-secondary);
    font-size: 0.875rem;
    font-weight: 500;
    cursor: pointer;
    border-radius: calc(var(--radius) / 2);
    transition: all 0.2s;
}

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

.tab-btn:not(.active):hover {
    background: var(--surface);
}

.code-content {
    flex: 1;
    overflow: auto;
    padding: 1.5rem;
}

.code-block {
    font-family: 'Consolas', 'Monaco', 'Courier New', monospace;
    font-size: 0.875rem;
    line-height: 1.6;
    white-space: pre;
    color: var(--text-primary);
}

.code-actions {
    padding: 1rem 1.5rem;
    border-top: 1px solid var(--border);
    display: flex;
    gap: 0.75rem;
}

.toast {
    position: fixed;
    bottom: 2rem;
    left: 50%;
    transform: translateX(-50%) translateY(100px);
    background: var(--text-primary);
    color: white;
    padding: 0.75rem 1.5rem;
    border-radius: var(--radius);
    font-size: 0.875rem;
    font-weight: 500;
    opacity: 0;
    transition: all 0.3s;
    z-index: 1000;
    pointer-events: none;
}

.toast.show {
    opacity: 1;
    transform: translateX(-50%) translateY(0);
}

@media (max-width: 1400px) {
    .code-panel {
        width: 350px;
    }
}

@media (max-width: 1200px) {
    .sidebar {
        width: 280px;
    }
    
    .code-panel {
        position: absolute;
        right: 0;
        top: 0;
        bottom: 0;
        transform: translateX(100%);
        transition: transform 0.3s;
        z-index: 50;
        box-shadow: -4px 0 16px rgba(0,0,0,0.1);
    }
    
    .code-panel.show {
        transform: translateX(0);
    }
}

@media (max-width: 768px) {
    .main-content {
        flex-direction: column;
    }
    
    .sidebar {
        width: 100%;
        border-right: none;
        border-bottom: 1px solid var(--border);
        max-height: 40vh;
    }
    
    .code-panel {
        width: 100%;
        position: static;
        transform: none;
        border-left: none;
        border-top: 1px solid var(--border);
    }
    
    .grid-container-wrapper {
        padding: 1rem;
    }
    
    .grid-container {
        height: 400px;
    }
    
    .template-grid {
        grid-template-columns: 1fr;
    }
    
    .item-properties-panel {
        position: fixed;
        right: 1rem;
        left: 1rem;
        width: auto;
        top: auto;
        bottom: 1rem;
        transform: none;
    }
}