:root {
    --bg-dark: #0F0F23;
    --surface: #1E1E34;
    --surface-hover: #2D2D4B;
    --border: #3A3A5A;
    
    --primary: #8B5CF6;
    --primary-hover: #7C3AED;
    
    --text-main: #F8FAFC;
    --text-muted: #94A3B8;
    
    --radius-lg: 12px;
    --radius-md: 8px;
    --radius-sm: 4px;
    
    --transition: 200ms ease;
}

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

body {
    font-family: 'Inter', system-ui, sans-serif;
    background-color: var(--bg-dark);
    color: var(--text-main);
    line-height: 1.5;
    height: 100vh;
    display: flex;
    flex-direction: column;
    overflow: hidden;
}

/* Header */
.app-header {
    height: 60px;
    background: var(--surface);
    border-bottom: 1px solid var(--border);
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 1.5rem;
    flex-shrink: 0;
}

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

.logo h1 {
    font-size: 1.1rem;
    font-weight: 700;
    color: var(--text-main);
    letter-spacing: -0.02em;
}

.logo span {
    font-weight: 400;
    color: var(--text-muted);
}

/* Layout */
.app-layout {
    display: flex;
    flex: 1;
    overflow: hidden;
}

/* Sidebar */
.sidebar {
    width: 320px;
    background: var(--surface);
    border-right: 1px solid var(--border);
    display: flex;
    flex-direction: column;
    overflow-y: auto;
}

/* Accordion */
.accordion {
    display: flex;
    flex-direction: column;
}

.accordion-item {
    border-bottom: 1px solid var(--border);
}

.accordion-header {
    width: 100%;
    padding: 1rem 1.5rem;
    background: transparent;
    border: none;
    color: var(--text-main);
    font-family: inherit;
    font-size: 0.9rem;
    font-weight: 600;
    text-align: left;
    display: flex;
    justify-content: space-between;
    align-items: center;
    cursor: pointer;
    transition: var(--transition);
}

.accordion-header:hover {
    background: var(--surface-hover);
}

.icon-chevron {
    transition: transform var(--transition);
    color: var(--text-muted);
}

.accordion-item.active .icon-chevron {
    transform: rotate(180deg);
}

.accordion-content {
    display: none;
    padding: 0 1.5rem 1.5rem;
}

.accordion-item.active .accordion-content {
    display: block;
}

/* Forms */
.form-group {
    margin-top: 1rem;
}

.form-group.inline-group {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.form-group label {
    display: block;
    font-size: 0.8rem;
    color: var(--text-muted);
    margin-bottom: 0.4rem;
}

.form-group.inline-group label {
    margin-bottom: 0;
}

textarea, input[type="text"], input[type="number"], select {
    width: 100%;
    background: rgba(0,0,0,0.2);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    padding: 0.5rem;
    color: var(--text-main);
    font-family: inherit;
    font-size: 0.85rem;
    transition: var(--transition);
}

textarea {
    resize: vertical;
}

textarea:focus, input:focus, select:focus {
    outline: none;
    border-color: var(--primary);
}

.color-picker-wrap {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.color-picker-wrap input[type="color"] {
    width: 32px;
    height: 32px;
    padding: 0;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    background: transparent;
}

.color-picker-wrap input[type="color"]::-webkit-color-swatch-wrapper {
    padding: 0;
}
.color-picker-wrap input[type="color"]::-webkit-color-swatch {
    border: 1px solid var(--border);
    border-radius: 4px;
}

.color-picker-wrap input[type="text"] {
    width: 80px;
    font-family: monospace;
}

/* Style Grids */
.style-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 0.5rem;
    margin-top: 0.5rem;
}

#cornerStyleGrid {
    grid-template-columns: repeat(3, 1fr);
}

.style-btn {
    background: rgba(0,0,0,0.2);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    aspect-ratio: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: var(--transition);
    color: var(--text-muted);
}

.style-btn:hover {
    border-color: var(--text-muted);
}

.style-btn.active {
    border-color: var(--primary);
    background: rgba(139, 92, 246, 0.1);
    color: var(--primary);
}

/* CSS Shapes for buttons */
.style-btn span {
    display: block;
    width: 16px;
    height: 16px;
    background: currentColor;
}
.shape-square { border-radius: 0; }
.shape-dot { border-radius: 50%; }
.shape-rounded { border-radius: 4px; }
.shape-diamond { transform: rotate(45deg); }

.style-btn span[class*="-outline"] {
    background: transparent;
    border: 3px solid currentColor;
}
.shape-square-outline { border-radius: 0; }
.shape-dot-outline { border-radius: 50%; }
.shape-rounded-outline { border-radius: 4px; }


/* File Drop */
.file-drop {
    border: 1px dashed var(--border);
    border-radius: var(--radius-md);
    padding: 1rem;
    text-align: center;
    cursor: pointer;
    background: rgba(0,0,0,0.1);
    font-size: 0.8rem;
    color: var(--text-muted);
    transition: var(--transition);
}

.file-drop:hover {
    border-color: var(--primary);
    background: rgba(139, 92, 246, 0.05);
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    padding: 0.5rem 1rem;
    border-radius: var(--radius-md);
    font-family: inherit;
    font-size: 0.875rem;
    font-weight: 500;
    cursor: pointer;
    transition: var(--transition);
    border: 1px solid transparent;
}

.btn-sm {
    padding: 0.35rem 0.75rem;
    font-size: 0.8rem;
}

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

.btn-outline {
    background: transparent;
    color: var(--text-main);
    border-color: var(--border);
}
.btn-outline:hover { background: var(--surface-hover); }

/* Workspace */
.workspace {
    flex: 1;
    position: relative;
    background: var(--bg-dark);
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: auto;
    padding: 2rem;
}

.preview-container {
    background: #ffffff;
    padding: 2rem;
    border-radius: var(--radius-lg);
    box-shadow: 0 20px 40px rgba(0,0,0,0.4);
    min-width: 300px;
    min-height: 300px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.canvas-wrapper {
    position: relative;
    width: 300px; /* Preview default size */
    height: 300px;
}

.checkers-bg {
    background-image: 
        linear-gradient(45deg, #e5e7eb 25%, transparent 25%), 
        linear-gradient(-45deg, #e5e7eb 25%, transparent 25%), 
        linear-gradient(45deg, transparent 75%, #e5e7eb 75%), 
        linear-gradient(-45deg, transparent 75%, #e5e7eb 75%);
    background-size: 20px 20px;
    background-position: 0 0, 0 10px, 10px -10px, -10px 0px;
    background-color: #f3f4f6;
}

canvas {
    width: 100% !important;
    height: 100% !important;
    display: block;
}

/* Generic Helpers */
.block { display: block; }
.w-full { width: 100%; }
.mt-2 { margin-top: 0.5rem; }
.ml-2 { margin-left: 0.5rem; }
.transparent-label { font-size: 0.75rem; color: var(--text-muted); display: inline-flex; align-items: center; cursor: pointer; }