/**
 * Grammar Tools - Complete Design System
 * Built for 100X Solutions
 * Dark SaaS Theme with Cyan Accents
 */

/* ============================================
   CSS RESET & BASE STYLES
   ============================================ */

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

:root {
    /* Color Palette */
    --bg-primary: #0F172A;
    --bg-secondary: #1E293B;
    --bg-tertiary: #334155;
    --text-primary: #FFFFFF;
    --text-secondary: #94A3B8;
    --text-muted: #64748B;
    
    /* Accent Colors */
    --accent-cyan: #22D3EE;
    --accent-blue: #38BDF8;
    --accent-gradient: linear-gradient(135deg, #22D3EE 0%, #38BDF8 100%);
    
    /* Status Colors */
    --success: #22C55E;
    --warning: #F59E0B;
    --error: #EF4444;
    --info: #3B82F6;
    
    /* UI Colors */
    --border-color: #334155;
    --input-bg: #1E293B;
    --card-bg: #1E293B;
    --hover-bg: #334155;
    
    /* Shadows */
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.3);
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.5);
    --shadow-glow: 0 0 20px rgba(34, 211, 238, 0.3);
    
    /* Typography */
    --font-primary: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --font-mono: 'SF Mono', 'Fira Code', monospace;
    
    /* Spacing */
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;
    
    /* Border Radius */
    --radius-sm: 6px;
    --radius-md: 8px;
    --radius-lg: 12px;
    --radius-xl: 16px;
    --radius-full: 9999px;
    
    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-normal: 250ms ease;
    --transition-slow: 350ms ease;
    
    /* Layout */
    --max-width: 1200px;
    --header-height: 70px;
    --sidebar-width: 280px;
}

html {
    font-size: 16px;
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-primary);
    background-color: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* ============================================
   TYPOGRAPHY
   ============================================ */

h1, h2, h3, h4, h5, h6 {
    font-weight: 700;
    line-height: 1.2;
    color: var(--text-primary);
}

h1 {
    font-size: 2.5rem;
    letter-spacing: -0.02em;
}

h2 {
    font-size: 2rem;
    letter-spacing: -0.01em;
}

h3 {
    font-size: 1.5rem;
}

h4 {
    font-size: 1.25rem;
}

h5 {
    font-size: 1.125rem;
}

h6 {
    font-size: 1rem;
}

p {
    color: var(--text-secondary);
    margin-bottom: var(--spacing-md);
}

a {
    color: var(--accent-cyan);
    text-decoration: none;
    transition: color var(--transition-fast);
}

a:hover {
    color: var(--accent-blue);
}

.text-muted {
    color: var(--text-muted);
}

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

/* ============================================
   LAYOUT
   ============================================ */

.container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 var(--spacing-lg);
}

.page-wrapper {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.main-content {
    flex: 1;
    padding: var(--spacing-xl) 0;
}

.section {
    margin-bottom: var(--spacing-2xl);
}

/* ============================================
   HEADER & NAVIGATION
   ============================================ */

.header {
    background-color: rgba(15, 23, 42, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border-color);
    position: sticky;
    top: 0;
    z-index: 1000;
    height: var(--header-height);
}

.header .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 100%;
}

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

.logo-icon {
    width: 40px;
    height: 40px;
    background: var(--accent-gradient);
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.25rem;
}

.logo-text {
    background: var(--accent-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.nav {
    display: flex;
    align-items: center;
    gap: var(--spacing-xl);
}

.nav-link {
    color: var(--text-secondary);
    font-weight: 500;
    padding: var(--spacing-sm) var(--spacing-md);
    border-radius: var(--radius-md);
    transition: all var(--transition-fast);
}

.nav-link:hover {
    color: var(--text-primary);
    background-color: var(--hover-bg);
}

.nav-link.active {
    color: var(--accent-cyan);
    background-color: rgba(34, 211, 238, 0.1);
}

.mobile-menu-btn {
    display: none;
    background: none;
    border: none;
    color: var(--text-primary);
    cursor: pointer;
    padding: var(--spacing-sm);
}

/* ============================================
   HERO SECTION
   ============================================ */

.hero {
    text-align: center;
    padding: var(--spacing-2xl) 0;
    margin-bottom: var(--spacing-xl);
}

.hero h1 {
    margin-bottom: var(--spacing-md);
    font-size: 3rem;
}

.hero h1 span {
    background: var(--accent-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero p {
    font-size: 1.25rem;
    max-width: 600px;
    margin: 0 auto var(--spacing-xl);
}

/* ============================================
   TOOL TABS NAVIGATION
   ============================================ */

.tool-tabs {
    display: flex;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-xl);
    overflow-x: auto;
    padding-bottom: var(--spacing-sm);
    scrollbar-width: thin;
    scrollbar-color: var(--border-color) transparent;
}

.tool-tab {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-md) var(--spacing-lg);
    background-color: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    color: var(--text-secondary);
    font-weight: 500;
    cursor: pointer;
    transition: all var(--transition-normal);
    white-space: nowrap;
}

.tool-tab:hover {
    border-color: var(--accent-cyan);
    color: var(--text-primary);
}

.tool-tab.active {
    background: var(--accent-gradient);
    border-color: transparent;
    color: var(--bg-primary);
}

.tool-tab-icon {
    font-size: 1.25rem;
}

.tool-tab-label {
    display: none;
}

@media (min-width: 640px) {
    .tool-tab-label {
        display: inline;
    }
}

/* ============================================
   TOOL PANELS
   ============================================ */

.tool-panel {
    display: none;
}

.tool-panel.active {
    display: block;
    animation: fadeIn var(--transition-normal);
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

.tool-header {
    margin-bottom: var(--spacing-lg);
}

.tool-header h2 {
    margin-bottom: var(--spacing-sm);
}

.tool-header p {
    color: var(--text-secondary);
}

.tool-content {
    display: grid;
    gap: var(--spacing-lg);
}

@media (min-width: 1024px) {
    .tool-content {
        grid-template-columns: 1fr 1fr;
    }
}

/* ============================================
   INPUT & OUTPUT AREAS
   ============================================ */

.io-container {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
}

.io-label {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: var(--spacing-sm);
}

.io-label-text {
    font-weight: 600;
    color: var(--text-primary);
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.io-textarea {
    width: 100%;
    min-height: 300px;
    padding: var(--spacing-lg);
    background-color: var(--input-bg);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-lg);
    color: var(--text-primary);
    font-family: var(--font-primary);
    font-size: 1rem;
    line-height: 1.7;
    resize: vertical;
    transition: all var(--transition-fast);
}

.io-textarea:focus {
    outline: none;
    border-color: var(--accent-cyan);
    box-shadow: var(--shadow-glow);
}

.io-textarea::placeholder {
    color: var(--text-muted);
}

.io-output {
    min-height: 300px;
    padding: var(--spacing-lg);
    background-color: var(--bg-secondary);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-lg);
    color: var(--text-primary);
    font-family: var(--font-primary);
    font-size: 1rem;
    line-height: 1.7;
    overflow-y: auto;
    white-space: pre-wrap;
    word-wrap: break-word;
}

.io-output.highlighted {
    border-color: var(--accent-cyan);
}

.io-output.empty {
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-muted);
    font-style: italic;
}

/* ============================================
   BUTTONS
   ============================================ */

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-md) var(--spacing-xl);
    border: none;
    border-radius: var(--radius-md);
    font-family: var(--font-primary);
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-normal);
}

.btn-primary {
    background: var(--accent-gradient);
    color: var(--bg-primary);
}

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

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

.btn-secondary {
    background-color: transparent;
    border: 2px solid var(--border-color);
    color: var(--text-primary);
}

.btn-secondary:hover {
    border-color: var(--accent-cyan);
    color: var(--accent-cyan);
}

.btn-ghost {
    background-color: transparent;
    color: var(--text-secondary);
}

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

.btn-icon {
    padding: var(--spacing-sm);
    border-radius: var(--radius-md);
}

.btn-lg {
    padding: var(--spacing-lg) var(--spacing-2xl);
    font-size: 1.125rem;
}

.btn-sm {
    padding: var(--spacing-sm) var(--spacing-md);
    font-size: 0.875rem;
}

.btn-group {
    display: flex;
    gap: var(--spacing-sm);
    flex-wrap: wrap;
}

/* ============================================
   FORM CONTROLS
   ============================================ */

.form-group {
    margin-bottom: var(--spacing-lg);
}

.form-label {
    display: block;
    margin-bottom: var(--spacing-sm);
    font-weight: 500;
    color: var(--text-primary);
}

.form-select {
    width: 100%;
    padding: var(--spacing-md);
    background-color: var(--input-bg);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    color: var(--text-primary);
    font-family: var(--font-primary);
    font-size: 1rem;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.form-select:focus {
    outline: none;
    border-color: var(--accent-cyan);
}

.form-select option {
    background-color: var(--bg-secondary);
}

.form-radio-group {
    display: flex;
    gap: var(--spacing-md);
    flex-wrap: wrap;
}

.form-radio {
    display: none;
}

.form-radio-label {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-md) var(--spacing-lg);
    background-color: var(--card-bg);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    color: var(--text-secondary);
    font-weight: 500;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.form-radio:checked + .form-radio-label {
    border-color: var(--accent-cyan);
    background-color: rgba(34, 211, 238, 0.1);
    color: var(--accent-cyan);
}

/* ============================================
   ISSUE HIGHLIGHTS (Grammar Checker)
   ============================================ */

.issue {
    position: relative;
    cursor: pointer;
}

.issue-warning {
    border-bottom: 2px solid var(--warning);
    background-color: rgba(245, 158, 11, 0.1);
}

.issue-error {
    border-bottom: 2px solid var(--error);
    background-color: rgba(239, 68, 68, 0.1);
}

.issue-info {
    border-bottom: 2px solid var(--info);
    background-color: rgba(59, 130, 246, 0.1);
}

.issue-tooltip {
    position: absolute;
    bottom: 100%;
    left: 50%;
    transform: translateX(-50%);
    padding: var(--spacing-sm) var(--spacing-md);
    background-color: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    font-size: 0.875rem;
    white-space: nowrap;
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-fast);
    z-index: 100;
}

.issue:hover .issue-tooltip {
    opacity: 1;
    visibility: visible;
}

/* ============================================
   STATS & METRICS
   ============================================ */

.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-lg);
}

.stat-item {
    background-color: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: var(--spacing-md);
    text-align: center;
}

.stat-value {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--accent-cyan);
}

.stat-label {
    font-size: 0.875rem;
    color: var(--text-secondary);
    margin-top: var(--spacing-xs);
}

.readability-meter {
    margin-top: var(--spacing-lg);
}

.readability-label {
    display: flex;
    justify-content: space-between;
    margin-bottom: var(--spacing-sm);
    font-size: 0.875rem;
    color: var(--text-secondary);
}

.readability-bar {
    height: 8px;
    background-color: var(--bg-tertiary);
    border-radius: var(--radius-full);
    overflow: hidden;
}

.readability-fill {
    height: 100%;
    background: var(--accent-gradient);
    border-radius: var(--radius-full);
    transition: width var(--transition-slow);
}

.readability-fill.easy {
    background-color: var(--success);
}

.readability-fill.medium {
    background-color: var(--warning);
}

.readability-fill.hard {
    background-color: var(--error);
}

/* ============================================
   ALERTS & NOTICES
   ============================================ */

.alert {
    padding: var(--spacing-md) var(--spacing-lg);
    border-radius: var(--radius-md);
    margin-bottom: var(--spacing-lg);
    display: flex;
    align-items: flex-start;
    gap: var(--spacing-md);
}

.alert-info {
    background-color: rgba(59, 130, 246, 0.1);
    border: 1px solid var(--info);
    color: var(--info);
}

.alert-warning {
    background-color: rgba(245, 158, 11, 0.1);
    border: 1px solid var(--warning);
    color: var(--warning);
}

.alert-success {
    background-color: rgba(34, 197, 94, 0.1);
    border: 1px solid var(--success);
    color: var(--success);
}

.alert-icon {
    flex-shrink: 0;
    font-size: 1.25rem;
}

.alert-content {
    flex: 1;
}

.alert-title {
    font-weight: 600;
    margin-bottom: var(--spacing-xs);
}

.alert-text {
    font-size: 0.875rem;
    color: var(--text-secondary);
    margin: 0;
}

/* ============================================
   FOOTER
   ============================================ */

.footer {
    background-color: var(--bg-secondary);
    border-top: 1px solid var(--border-color);
    padding: var(--spacing-2xl) 0;
    margin-top: var(--spacing-2xl);
}

.footer-grid {
    display: grid;
    gap: var(--spacing-xl);
    margin-bottom: var(--spacing-xl);
}

@media (min-width: 768px) {
    .footer-grid {
        grid-template-columns: 2fr 1fr 1fr 1fr;
    }
}

.footer-brand {
    max-width: 300px;
}

.footer-logo {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: var(--spacing-md);
}

.footer-desc {
    color: var(--text-secondary);
    font-size: 0.875rem;
    line-height: 1.6;
}

.footer-title {
    font-weight: 600;
    margin-bottom: var(--spacing-md);
    color: var(--text-primary);
}

.footer-links {
    list-style: none;
}

.footer-links li {
    margin-bottom: var(--spacing-sm);
}

.footer-links a {
    color: var(--text-secondary);
    font-size: 0.875rem;
    transition: color var(--transition-fast);
}

.footer-links a:hover {
    color: var(--accent-cyan);
}

.footer-bottom {
    padding-top: var(--spacing-xl);
    border-top: 1px solid var(--border-color);
    text-align: center;
    color: var(--text-muted);
    font-size: 0.875rem;
}

/* ============================================
   LEGAL PAGES
   ============================================ */

.legal-content {
    max-width: 800px;
    margin: 0 auto;
}

.legal-content h1 {
    margin-bottom: var(--spacing-xl);
}

.legal-content h2 {
    margin-top: var(--spacing-xl);
    margin-bottom: var(--spacing-md);
    font-size: 1.5rem;
}

.legal-content p {
    margin-bottom: var(--spacing-md);
    line-height: 1.8;
}

.legal-content ul, .legal-content ol {
    margin-bottom: var(--spacing-md);
    padding-left: var(--spacing-xl);
    color: var(--text-secondary);
}

.legal-content li {
    margin-bottom: var(--spacing-sm);
    line-height: 1.6;
}

.last-updated {
    color: var(--text-muted);
    font-size: 0.875rem;
    margin-bottom: var(--spacing-xl);
}

/* ============================================
   CONTACT PAGE
   ============================================ */

.contact-grid {
    display: grid;
    gap: var(--spacing-xl);
}

@media (min-width: 768px) {
    .contact-grid {
        grid-template-columns: 1fr 1fr;
    }
}

.contact-info {
    background-color: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: var(--spacing-xl);
}

.contact-info-item {
    display: flex;
    align-items: flex-start;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-lg);
}

.contact-info-icon {
    width: 48px;
    height: 48px;
    background: var(--accent-gradient);
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.25rem;
    flex-shrink: 0;
}

.contact-info-label {
    font-size: 0.875rem;
    color: var(--text-muted);
    margin-bottom: var(--spacing-xs);
}

.contact-info-value {
    color: var(--text-primary);
    font-weight: 500;
}

.contact-form {
    background-color: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: var(--spacing-xl);
}

.form-row {
    display: grid;
    gap: var(--spacing-md);
}

@media (min-width: 640px) {
    .form-row {
        grid-template-columns: 1fr 1fr;
    }
}

.form-input {
    width: 100%;
    padding: var(--spacing-md);
    background-color: var(--input-bg);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    color: var(--text-primary);
    font-family: var(--font-primary);
    font-size: 1rem;
    transition: all var(--transition-fast);
}

.form-input:focus {
    outline: none;
    border-color: var(--accent-cyan);
}

.form-input::placeholder {
    color: var(--text-muted);
}

.form-textarea {
    min-height: 150px;
    resize: vertical;
}

.form-submit {
    width: 100%;
    margin-top: var(--spacing-md);
}

/* ============================================
   TOAST NOTIFICATIONS
   ============================================ */

.toast-container {
    position: fixed;
    bottom: var(--spacing-xl);
    right: var(--spacing-xl);
    z-index: 2000;
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}

.toast {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    padding: var(--spacing-md) var(--spacing-lg);
    background-color: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-lg);
    animation: slideIn var(--transition-normal);
}

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

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

.toast-icon {
    font-size: 1.25rem;
}

.toast-message {
    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%);
    }
}

/* ============================================
   LOADING STATES
   ============================================ */

.loading-spinner {
    width: 40px;
    height: 40px;
    border: 3px solid var(--border-color);
    border-top-color: var(--accent-cyan);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

.loading-overlay {
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 200px;
}

/* ============================================
   RESPONSIVE DESIGN
   ============================================ */

@media (max-width: 1024px) {
    :root {
        --header-height: 60px;
    }
    
    h1 {
        font-size: 2rem;
    }
    
    h2 {
        font-size: 1.5rem;
    }
    
    .hero h1 {
        font-size: 2.5rem;
    }
}

@media (max-width: 768px) {
    .nav {
        display: none;
    }
    
    .mobile-menu-btn {
        display: block;
    }
    
    .tool-content {
        grid-template-columns: 1fr;
    }
    
    .io-textarea,
    .io-output {
        min-height: 250px;
    }
    
    .btn-lg {
        padding: var(--spacing-md) var(--spacing-xl);
        font-size: 1rem;
    }
    
    .stats-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .footer-grid {
        grid-template-columns: 1fr 1fr;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 var(--spacing-md);
    }
    
    h1 {
        font-size: 1.75rem;
    }
    
    .hero h1 {
        font-size: 2rem;
    }
    
    .tool-tabs {
        gap: var(--spacing-xs);
    }
    
    .tool-tab {
        padding: var(--spacing-sm) var(--spacing-md);
        font-size: 0.875rem;
    }
    
    .btn-group {
        flex-direction: column;
    }
    
    .btn {
        width: 100%;
    }
    
    .stats-grid {
        grid-template-columns: 1fr 1fr;
        gap: var(--spacing-sm);
    }
    
    .stat-item {
        padding: var(--spacing-sm);
    }
    
    .stat-value {
        font-size: 1.25rem;
    }
    
    .toast-container {
        left: var(--spacing-md);
        right: var(--spacing-md);
        bottom: var(--spacing-md);
    }
}

/* ============================================
   UTILITY CLASSES
   ============================================ */

.visually-hidden {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

.mt-sm { margin-top: var(--spacing-sm); }
.mt-md { margin-top: var(--spacing-md); }
.mt-lg { margin-top: var(--spacing-lg); }
.mt-xl { margin-top: var(--spacing-xl); }

.mb-sm { margin-bottom: var(--spacing-sm); }
.mb-md { margin-bottom: var(--spacing-md); }
.mb-lg { margin-bottom: var(--spacing-lg); }
.mb-xl { margin-bottom: var(--spacing-xl); }

.flex { display: flex; }
.flex-col { flex-direction: column; }
.items-center { align-items: center; }
.justify-between { justify-content: space-between; }
.gap-sm { gap: var(--spacing-sm); }
.gap-md { gap: var(--spacing-md); }
.gap-lg { gap: var(--spacing-lg); }

.hidden { display: none; }
.block { display: block; }
.inline-block { display: inline-block; }

.w-full { width: 100%; }
.h-full { height: 100%; }

/* Scrollbar Styling */
::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

::-webkit-scrollbar-track {
    background: var(--bg-secondary);
}

::-webkit-scrollbar-thumb {
    background: var(--border-color);
    border-radius: var(--radius-full);
}

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

/* Selection */
::selection {
    background-color: var(--accent-cyan);
    color: var(--bg-primary);
}

/* Focus visible */
:focus-visible {
    outline: 2px solid var(--accent-cyan);
    outline-offset: 2px;
}

/* Print styles */
@media print {
    .header,
    .footer,
    .tool-tabs,
    .btn-group {
        display: none;
    }
    
    body {
        background: white;
        color: black;
    }
    
    .io-output {
        border: 1px solid #ccc;
    }
}