:root {
    --bg-color: #0f172a;
    --surface-color: #1e293b;
    --surface-hover: #334155;
    --primary-color: #3b82f6;
    --primary-hover: #2563eb;
    --text-primary: #f8fafc;
    --text-secondary: #94a3b8;
    --border-color: #334155;
    --success-color: #22c55e;

    --font-main: 'Inter', system-ui, -apple-system, sans-serif;

    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);

    --radius-lg: 1rem;
    --radius-md: 0.75rem;
    --radius-sm: 0.5rem;
}

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

body {
    font-family: var(--font-main);
    background-color: var(--bg-color);
    color: var(--text-primary);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    overflow-x: hidden;
}

.app-container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 2rem;
    width: 100%;
    flex: 1;
    display: flex;
    flex-direction: column;
}

/* Header */
.app-header {
    text-align: center;
    margin-bottom: 3rem;
    animation: fadeInDown 0.8s ease-out;
}

.logo {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.75rem;
    margin-bottom: 0.5rem;
}

.logo h1 {
    font-size: 2.5rem;
    font-weight: 700;
    background: linear-gradient(135deg, #60a5fa, #a855f7);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    letter-spacing: -0.05em;
}

.logo .icon {
    font-size: 2.5rem;
}

.tagline {
    color: var(--text-secondary);
    font-size: 1.1rem;
}

/* Workspace */
.workspace {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    position: relative;
}

/* Upload Zone */
.upload-zone {
    width: 100%;
    max-width: 800px;
    height: 400px;
    background-color: var(--surface-color);
    border: 3px dashed var(--border-color);
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all 0.3s ease;
    animation: fadeInUp 0.8s ease-out 0.2s backwards;
}

.upload-zone:hover,
.upload-zone.drag-over {
    border-color: var(--primary-color);
    background-color: var(--surface-hover);
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.upload-content {
    text-align: center;
    color: var(--text-secondary);
}

.upload-icon {
    width: 64px;
    height: 64px;
    margin-bottom: 1.5rem;
    color: var(--primary-color);
    opacity: 0.8;
}

.upload-content h3 {
    font-size: 1.5rem;
    color: var(--text-primary);
    margin-bottom: 0.5rem;
}

.upload-content .highlight {
    color: var(--primary-color);
    text-decoration: underline;
    text-underline-offset: 4px;
}

/* Editor Area - Main Layout */
.editor-area {
    display: grid;
    grid-template-columns: 1fr 340px;
    gap: 2rem;
    width: 100%;
    height: 100%;
    min-height: 600px;
    animation: fadeIn 0.5s ease-out;
}

.editor-area.hidden {
    display: none;
}

/* Canvas Wrapper */
.canvas-wrapper {
    background-color: #020617;
    /* Very dark for contrast */
    border-radius: var(--radius-lg);
    overflow: hidden;
    position: relative;
    box-shadow: inset 0 0 20px rgb(0 0 0 / 0.5);
    display: flex;
    align-items: center;
    justify-content: center;
    border: 1px solid var(--border-color);
    cursor: crosshair;
}

canvas {
    max-width: 100%;
    max-height: 80vh;
    box-shadow: var(--shadow-xl);
}

/* Magnifier */
.magnifier {
    position: absolute;
    width: 120px;
    height: 120px;
    border: 3px solid #fff;
    border-radius: 50%;
    pointer-events: none;
    z-index: 100;
    box-shadow: 0 0 0 3px rgba(0, 0, 0, 0.3), var(--shadow-lg);
    background-repeat: no-repeat;
    background-color: var(--surface-color);
    /* Fallback */
    display: none;
    /* Controlled by JS */
    image-rendering: pixelated;
    /* Crisp pixels for zoom */
}

.magnifier.hidden {
    display: none !important;
}

/* Color Panel Sidebar */
.color-panel {
    background-color: var(--surface-color);
    border-radius: var(--radius-lg);
    padding: 2rem;
    display: flex;
    flex-direction: column;
    gap: 2rem;
    border: 1px solid var(--border-color);
    height: fit-content;
    position: sticky;
    top: 2rem;
}

.color-preview-card {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1rem;
    margin-bottom: 0.5rem;
}

.preview-group {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    align-items: center;
    /* Center labels */
}

.preview-label {
    font-size: 0.75rem;
    font-weight: 700;
    color: var(--text-secondary);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    text-align: center;
}

.preview-box {
    width: 100%;
    aspect-ratio: 16/10;
    /* More rectangular, less huge */
    background-color: transparent;
    border-radius: var(--radius-md);
    border: 2px solid var(--border-color);
    box-shadow: inset 0 2px 4px 0 rgb(0 0 0 / 0.05);
    /* Inset shadow for depth */
    transition: background-color 0.1s, border-color 0.2s, transform 0.2s;
    background-image:
        linear-gradient(45deg, #2e2e2e 25%, transparent 25%),
        linear-gradient(-45deg, #2e2e2e 25%, transparent 25%),
        linear-gradient(45deg, transparent 75%, #2e2e2e 75%),
        linear-gradient(-45deg, transparent 75%, #2e2e2e 75%);
    background-size: 16px 16px;
    /* Smaller pattern */
    background-position: 0 0, 0 8px, 8px -8px, -8px 0px;
}

/* Distinct style for Locked box when active */
#preview-locked {
    border-width: 2px;
}

/* Subtle pulse for Live box to indicate activity */
#preview-hover::after {
    content: '';
    display: block;
    width: 100%;
    height: 100%;
    box-shadow: 0 0 0 0 rgba(59, 130, 246, 0);
    /* Primary color fade */
}

.value-group {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.value-group label {
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--text-secondary);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

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

.copy-input input {
    flex: 1;
    background-color: var(--bg-color);
    border: 1px solid var(--border-color);
    padding: 0.75rem 1rem;
    border-radius: var(--radius-sm);
    color: var(--text-primary);
    font-family: 'Courier New', monospace;
    font-size: 1rem;
    outline: none;
    transition: border-color 0.2s;
}

.copy-input input:focus {
    border-color: var(--primary-color);
}

.icon-btn {
    background-color: var(--surface-hover);
    border: none;
    color: var(--text-primary);
    width: 48px;
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: all 0.2s;
    display: flex;
    align-items: center;
    justify-content: center;
}

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

.icon-btn svg {
    width: 20px;
    height: 20px;
}

.reset-btn {
    margin-top: auto;
    background-color: transparent;
    border: 1px solid var(--border-color);
    color: var(--text-secondary);
    padding: 1rem;
    border-radius: var(--radius-sm);
    cursor: pointer;
    font-weight: 500;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    transition: all 0.2s;
}

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

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

/* Toast Notification */
.toast {
    position: fixed;
    bottom: 2rem;
    left: 50%;
    transform: translateX(-50%);
    background-color: var(--success-color);
    color: white;
    padding: 0.75rem 1.5rem;
    border-radius: 9999px;
    font-weight: 500;
    box-shadow: var(--shadow-lg);
    z-index: 1000;
    transition: transform 0.3s ease, opacity 0.3s ease;
}

.toast.hidden {
    transform: translate(-50%, 20px);
    opacity: 0;
    pointer-events: none;
}

/* Animations */
@keyframes fadeInDown {
    from {
        opacity: 0;
        transform: translateY(-20px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes fadeIn {
    from {
        opacity: 0;
    }

    to {
        opacity: 1;
    }
}

/* Responsive */
@media (max-width: 900px) {
    .editor-area {
        grid-template-columns: 1fr;
    }

    .color-panel {
        position: static;
        flex-direction: row;
        flex-wrap: wrap;
        align-items: center;
    }

    .color-preview-card {
        flex: 1;
        min-width: 280px;
        flex-direction: row;
    }

    .preview-box {
        width: 100px;
        aspect-ratio: 1;
    }

    .reset-btn {
        margin-top: 0;
        width: 100%;
    }
}

@media (max-width: 600px) {
    .app-header h1 {
        font-size: 2rem;
    }

    .color-preview-card {
        flex-direction: column;
    }

    .preview-box {
        width: 100%;
        aspect-ratio: 16/9;
    }
}