/* Liquid Glass Previewer - MIT License
   Copyright (c) 2026 Eri Tools */
:root {
    /* Color System */
    --bg-primary: #fafafa;
    --bg-secondary: #ffffff;
    --bg-tertiary: #f5f5f5;
    --text-primary: #1a1a1a;
    --text-secondary: #666666;
    --text-tertiary: #999999;
    --accent: #0066cc;
    --accent-hover: #0052a3;
    --border: #e5e5e5;
    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.08);
    --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.12);
    --icon-display-size: 180px;
    
    /* Typography */
    --font-body: 'DM Sans', -apple-system, BlinkMacSystemFont, sans-serif;
    --font-mono: 'JetBrains Mono', 'SF Mono', monospace;
    
    /* Spacing */
    --space-xs: 0.5rem;
    --space-sm: 1rem;
    --space-md: 1.5rem;
    --space-lg: 2rem;
    --space-xl: 3rem;
    --space-2xl: 4rem;
    
    /* Border Radius */
    --radius-sm: 6px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --radius-xl: 24px;
    
    /* Transitions */
    --transition-base: 200ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 350ms cubic-bezier(0.4, 0, 0.2, 1);
}

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

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

body {
    font-family: var(--font-body);
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--space-md);
    width: 100%;
}

/* Language Toggle */
.lang-toggle {
    position: fixed;
    top: var(--space-md);
    right: var(--space-md);
    z-index: 100;
    display: flex;
    gap: 4px;
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    padding: 4px;
    box-shadow: var(--shadow-sm);
}

.lang-btn {
    background: transparent;
    border: none;
    padding: 6px 12px;
    border-radius: 4px;
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--text-secondary);
    cursor: pointer;
    transition: all var(--transition-base);
    font-family: var(--font-body);
}

.lang-btn:hover {
    color: var(--text-primary);
    background: var(--bg-tertiary);
}

.lang-btn.active {
    background: var(--accent);
    color: white;
}

/* Header */
.header {
    padding: var(--space-xl) 0 var(--space-lg);
    text-align: center;
    animation: fadeInUp 600ms ease-out;
}

.brand {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-sm);
    margin-bottom: var(--space-sm);
}

.logo {
    color: var(--accent);
    animation: fadeIn 800ms ease-out 200ms backwards;
}

.brand-text h1 {
    font-size: 1.75rem;
    font-weight: 700;
    letter-spacing: -0.02em;
    color: var(--text-primary);
    animation: fadeIn 800ms ease-out 300ms backwards;
}

.brand-by {
    font-size: 0.875rem;
    color: var(--text-secondary);
    margin-top: 4px;
    animation: fadeIn 800ms ease-out 400ms backwards;
}

.eri-tools {
    color: var(--accent);
    font-weight: 600;
}

.tagline {
    font-size: 1rem;
    color: var(--text-secondary);
    max-width: 500px;
    margin: 0 auto;
    animation: fadeIn 800ms ease-out 500ms backwards;
}

.header-support {
    margin-top: var(--space-md);
    display: flex;
    justify-content: center;
}

/* Main */
.main {
    flex: 1;
    padding-bottom: var(--space-2xl);
}

/* Upload Section */
.upload-section {
    margin-bottom: calc(var(--space-md) + 8px);
    animation: fadeInUp 800ms ease-out 600ms backwards;
}

.upload-zone {
    background: var(--bg-secondary);
    border: 2px dashed var(--border);
    border-radius: var(--radius-lg);
    padding: var(--space-lg);
    text-align: center;
    transition: all var(--transition-base);
    cursor: pointer;
}

.upload-zone:hover {
    border-color: var(--accent);
    background: #fafcff;
}

.upload-zone.dragover {
    border-color: var(--accent);
    background: #f0f7ff;
    transform: scale(1.01);
}

.upload-icon {
    color: var(--text-tertiary);
    margin-bottom: var(--space-md);
}

.upload-zone h2 {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--space-xs);
}

.upload-zone p {
    font-size: 0.875rem;
    color: var(--text-secondary);
    margin-bottom: var(--space-md);
}

.btn-primary {
    background: var(--accent);
    color: white;
    border: none;
    padding: 12px 24px;
    border-radius: var(--radius-sm);
    font-size: 0.9375rem;
    font-weight: 500;
    cursor: pointer;
    transition: all var(--transition-base);
    font-family: var(--font-body);
}

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

.btn-primary:active {
    transform: translateY(0);
}

/* Controls Section */
.controls-section {
    margin-bottom: var(--space-sm);
    animation: fadeInUp 400ms ease-out;
}

.controls-row {
    display: flex;
    align-items: center;
    gap: var(--space-md);
    flex-wrap: wrap;
    margin-bottom: var(--space-sm);
}

.controls-section h3 {
    font-size: 0.875rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--text-secondary);
    margin-bottom: 0;
}

.color-presets {
    display: flex;
    gap: var(--space-sm);
    flex-wrap: wrap;
}

.color-btn {
    width: 56px;
    height: 56px;
    border: 2px solid transparent;
    border-radius: var(--radius-sm);
    background: var(--bg-secondary);
    cursor: pointer;
    transition: all var(--transition-base);
    padding: 4px;
    position: relative;
}

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

.color-btn.active {
    border-color: var(--accent);
    box-shadow: 0 0 0 3px rgba(0, 102, 204, 0.1);
}

.color-swatch {
    width: 100%;
    height: 100%;
    border-radius: 4px;
    border: 1px solid rgba(0, 0, 0, 0.1);
    display: flex;
    align-items: center;
    justify-content: center;
}

.color-custom .custom-swatch {
    background: linear-gradient(135deg, 
        #ff0000 0%, #ff7f00 16.66%, #ffff00 33.33%, 
        #00ff00 50%, #0000ff 66.66%, #4b0082 83.33%, #9400d3 100%);
}

.color-custom svg {
    filter: drop-shadow(0 1px 2px rgba(0, 0, 0, 0.3));
}

.color-custom {
    position: relative;
    overflow: hidden;
}

#colorPicker {
    position: absolute;
    inset: 0;
    opacity: 0;
    cursor: pointer;
}

#baseColorPicker {
    position: absolute;
    inset: 0;
    opacity: 0;
    cursor: pointer;
}

/* Preview Section */
.preview-section {
    animation: fadeInUp 400ms ease-out;
}

.preview-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: var(--space-lg);
    margin-bottom: var(--space-md);
}

.preview-card {
    background: var(--bg-secondary);
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow-sm);
    transition: all var(--transition-base);
}

.preview-card:hover {
    box-shadow: var(--shadow-md);
    transform: translateY(-2px);
}

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

.preview-header h4 {
    font-size: 0.9375rem;
    font-weight: 600;
    color: var(--text-primary);
}

.badge {
    font-size: 0.75rem;
    font-weight: 600;
    padding: 4px 8px;
    background: var(--accent);
    color: white;
    border-radius: 4px;
    text-transform: uppercase;
    letter-spacing: 0.03em;
}

.preview-canvas {
    padding: var(--space-md);
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 240px;
    background: var(--bg-tertiary);
    transition: background var(--transition-slow);
}

.preview-canvas canvas {
    width: var(--icon-display-size);
    height: var(--icon-display-size);
    border-radius: 0;
    box-shadow: none;
}

/* Info Section */
.info-section {
    margin-top: calc(var(--space-md) + 8px);
    animation: fadeInUp 800ms ease-out 700ms backwards;
}

.info-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--space-lg);
}

.info-card {
    background: var(--bg-secondary);
    padding: var(--space-lg);
    border-radius: var(--radius-md);
    border: 1px solid var(--border);
}

.info-card h3 {
    font-size: 1rem;
    font-weight: 600;
    margin-bottom: var(--space-sm);
    color: var(--text-primary);
}

.info-card p {
    font-size: 0.9375rem;
    color: var(--text-secondary);
    line-height: 1.7;
}

/* Footer */
.footer {
    background: var(--bg-secondary);
    border-top: 1px solid var(--border);
    padding: var(--space-md) 0;
    margin-top: calc(var(--space-md) - 24px);
}

.footer-content {
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 6px;
    flex-wrap: wrap;
    gap: 12px;
}

.footer-brand p {
    font-size: 0.9375rem;
    color: var(--text-secondary);
}

.eri-tools-link {
    color: var(--accent);
    text-decoration: none;
    font-weight: 600;
    transition: color var(--transition-base);
}

.eri-tools-link:hover {
    color: var(--accent-hover);
}

.kofi-btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    background: #13C3FF;
    color: white;
    padding: 10px 20px;
    border-radius: var(--radius-sm);
    text-decoration: none;
    font-weight: 500;
    font-size: 0.9375rem;
    transition: all var(--transition-base);
    box-shadow: var(--shadow-sm);
}

.kofi-btn:hover {
    background: #0fb5ec;
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

.kofi-btn--top {
    padding: 8px 16px;
    font-size: 0.875rem;
}

.footer-meta {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 12px;
    flex-wrap: wrap;
    font-size: 0.8125rem;
    color: var(--text-tertiary);
    text-align: center;
}

.footer-license {
    font-size: 0.8125rem;
    color: var(--text-tertiary);
}

.footer-source a {
    font-size: 0.8125rem;
    color: var(--text-tertiary);
    text-decoration: none;
}

.footer-source a:hover {
    color: var(--text-secondary);
}

.footer-copyright {
    font-size: 0.8125rem;
    color: var(--text-tertiary);
    text-align: center;
    margin-top: 6px;
}

/* Animations */
@keyframes fadeIn {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Responsive */
@media (max-width: 768px) {
    .header {
        padding: var(--space-xl) 0 var(--space-lg);
    }

    .brand {
        flex-direction: column;
        gap: var(--space-xs);
    }

    .brand-text h1 {
        font-size: 1.5rem;
    }

    .tagline {
        font-size: 0.9375rem;
    }

    .preview-grid {
        grid-template-columns: 1fr;
    }

    :root {
        --icon-display-size: 160px;
    }

    .footer-content {
        flex-direction: column;
        text-align: center;
    }

    .footer-meta {
        flex-direction: column;
        gap: 4px;
    }

    .lang-toggle {
        top: var(--space-sm);
        right: var(--space-sm);
    }
}

/* Print */
@media print {
    .lang-toggle,
    .upload-section,
    .controls-section,
    .info-section,
    .footer {
        display: none;
    }
}