/**
 * Master CSS - Student Test Software Platform
 * Central design system based on DESIGN_GUIDELINE.html
 *
 * This file contains:
 * - CSS Custom Properties (Design Tokens)
 * - Global Typography
 * - Button Styles
 * - Common Components
 * - Utility Classes
 * - Responsive Breakpoints
 *
 * Last Updated: 2025-11-10
 */

/* ============================================
   CSS CUSTOM PROPERTIES (Design Tokens)
   ============================================ */

:root {
    /* Primary Colors - Linglee Design System */
    --color-primary: #4E5FE5;           /* Primary blue */
    --color-primary-blue: #4E5FE5;      /* Alias for compatibility */
    --color-primary-light: #7C8AFF;     /* Lighter variation */
    --color-accent-coral: #E56B6F;      /* Coral/red accent */
    --color-accent-purple: #8E94F2;     /* Periwinkle/lavender */
    --color-accent-lavender: #A5B4FC;   /* Soft lavender (alias) */
    --color-accent-yellow: #FFC857;     /* Yellow accent */
    --color-success-green: #4AD295;     /* Success green */

    /* Background Colors */
    --color-white: #FFFFFF;
    --color-bg-white: #FFFFFF;          /* Alias */
    --color-bg-body: #F5F6FA;           /* Very light cool gray/blue */
    --color-bg-light-gray: #F5F7FA;     /* Alias for compatibility */
    --color-bg-soft-pink: #FDECEE;      /* Soft pink for banners */
    --color-bg-light-blue: #E8EAF6;     /* Soft blue backgrounds */
    --color-bg-soft-blue: #E8EAF6;      /* Alias */

    /* Text Colors - Linglee Design System */
    --color-text-dark: #2D3142;         /* Deep navy for headings */
    --color-text-medium: #808390;       /* Softer gray for body */
    --color-text-light: #B0B5C4;        /* Placeholders/disabled */
    --color-text-white: #FFFFFF;        /* White text */
    --color-border: #ECEEF5;            /* Border color */

    /* Semantic Colors */
    --color-gray-50: #F7FAFC;
    --color-gray-100: #EDF2F7;
    --color-gray-200: #E2E8F0;
    --color-gray-300: #CBD5E0;
    --color-gray-400: #A0AEC0;
    --color-gray-500: #718096;
    --color-gray-600: #4A5568;
    --color-gray-700: #2D3748;
    --color-gray-800: #1A202C;
    --color-gray-900: #171923;

    --color-black: #000000;

    /* Success/Error Colors (keep for alerts) */
    --color-success: #48BB78;
    --color-success-bg: #C6F6D5;
    --color-error: #F56565;
    --color-error-bg: #FED7D7;
    --color-warning: #ED8936;
    --color-warning-bg: #FEEBC8;
    --color-info: #4299E1;
    --color-info-bg: #BEE3F8;

    /* Shadows - Linglee Design System */
    --shadow-xs: 0 1px 3px rgba(0, 0, 0, 0.04);
    --shadow-sm: 0 2px 5px rgba(0, 0, 0, 0.02);
    --shadow-md: 0 4px 20px rgba(0, 0, 0, 0.05);
    --shadow-lg: 0 4px 24px rgba(0, 0, 0, 0.08);
    --shadow-xl: 0 8px 40px rgba(0, 0, 0, 0.10);
    --shadow-card: 0 10px 30px rgba(78, 95, 229, 0.08);
    --shadow-hover: 0 15px 35px rgba(78, 95, 229, 0.15);
    --shadow-button: 0 4px 15px rgba(78, 95, 229, 0.25);
    --shadow-button-blue: 0 4px 15px rgba(78, 95, 229, 0.25);
    --shadow-button-blue-hover: 0 6px 20px rgba(78, 95, 229, 0.4);
    --shadow-button-coral: 0 4px 12px rgba(255, 107, 107, 0.3);
    --shadow-button-coral-hover: 0 6px 20px rgba(255, 107, 107, 0.4);

    /* Typography */
    --font-family-base: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    --font-family-mono: 'Courier New', monospace;

    --font-size-xs: 12px;
    --font-size-sm: 13px;
    --font-size-base: 16px;
    --font-size-lg: 18px;
    --font-size-xl: 24px;
    --font-size-2xl: 32px;
    --font-size-3xl: 48px;

    --font-weight-normal: 400;
    --font-weight-medium: 500;
    --font-weight-semibold: 600;
    --font-weight-bold: 700;

    --line-height-tight: 1.2;
    --line-height-base: 1.6;
    --line-height-relaxed: 1.8;

    /* Spacing */
    --spacing-xs: 4px;
    --spacing-sm: 8px;
    --spacing-md: 16px;
    --spacing-lg: 24px;
    --spacing-xl: 32px;
    --spacing-2xl: 48px;
    --spacing-3xl: 64px;

    /* Border Radius - Linglee Design System */
    --radius-sm: 6px;
    --radius-md: 12px;
    --radius-lg: 20px;
    --radius-xl: 24px;
    --radius-2xl: 32px;
    --radius-full: 9999px;
    --radius-circle: 50%;

    /* Transitions */
    --transition-fast: 0.15s ease;
    --transition-base: 0.3s ease;
    --transition-slow: 0.5s ease;

    /* Z-Index Layers */
    --z-base: 1;
    --z-dropdown: 100;
    --z-sticky: 500;
    --z-fixed: 1000;
    --z-modal-backdrop: 1040;
    --z-modal: 1050;
    --z-popover: 1060;
    --z-tooltip: 1070;

    /* Responsive Breakpoints */
    --breakpoint-xs: 480px;
    --breakpoint-sm: 640px;
    --breakpoint-md: 768px;
    --breakpoint-lg: 1024px;
    --breakpoint-xl: 1280px;
    --breakpoint-2xl: 1536px;

    /* Effects */
    --backdrop-blur: blur(10px);
    --opacity-disabled: 0.6;
    --opacity-hover: 0.9;
}

/* ============================================
   GLOBAL RESETS & BASE STYLES
   ============================================ */

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

body {
    font-family: var(--font-family-base);
    font-size: var(--font-size-base);
    line-height: var(--line-height-base);
    color: var(--color-text-dark);
    background: var(--color-bg-light-gray);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

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

h1, h2, h3, h4, h5, h6 {
    font-weight: var(--font-weight-semibold);
    line-height: var(--line-height-tight);
    color: var(--color-text-dark);
    margin-bottom: var(--spacing-md);
}

h1 {
    font-size: var(--font-size-3xl);
    font-weight: var(--font-weight-bold);
}

h2 {
    font-size: var(--font-size-2xl);
    border-bottom: 3px solid var(--color-primary-blue);
    padding-bottom: var(--spacing-sm);
}

h3 {
    font-size: var(--font-size-xl);
    color: var(--color-gray-600);
}

h4 {
    font-size: var(--font-size-lg);
}

h5, h6 {
    font-size: var(--font-size-base);
}

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

a {
    color: var(--color-primary-blue);
    text-decoration: none;
    transition: color var(--transition-base);
}

a:hover {
    color: var(--color-accent-coral);
    text-decoration: underline;
}

code {
    background: var(--color-gray-100);
    padding: 3px 8px;
    border-radius: var(--radius-sm);
    font-family: var(--font-family-mono);
    color: var(--color-primary-blue);
    font-size: var(--font-size-sm);
}

pre {
    background: var(--color-gray-100);
    padding: var(--spacing-md);
    border-radius: var(--radius-md);
    overflow-x: auto;
    margin-bottom: var(--spacing-md);
}

pre code {
    background: none;
    padding: 0;
}

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

.btn {
    display: inline-block;
    padding: 14px 32px;
    font-size: var(--font-size-base);
    font-weight: var(--font-weight-semibold);
    text-align: center;
    text-decoration: none;
    border: none;
    border-radius: var(--radius-lg);
    cursor: pointer;
    transition: all var(--transition-base);
    font-family: var(--font-family-base);
}

/* Primary Button (Blue) */
.btn-primary {
    background: var(--color-primary-blue);
    color: var(--color-white);
    box-shadow: var(--shadow-button-blue);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-button-blue-hover);
    text-decoration: none;
    color: var(--color-white);
}

/* Coral Button */
.btn-coral {
    background: var(--color-accent-coral);
    color: var(--color-white);
    box-shadow: var(--shadow-button-coral);
}

.btn-coral:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-button-coral-hover);
    text-decoration: none;
    color: var(--color-white);
}

/* Secondary Button */
.btn-secondary {
    background: var(--color-gray-200);
    color: var(--color-gray-900);
    box-shadow: var(--shadow-sm);
}

.btn-secondary:hover {
    background: var(--color-gray-300);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

/* Outline Button */
.btn-outline {
    background: var(--color-white);
    color: var(--color-primary-blue);
    border: 2px solid var(--color-primary-blue);
    box-shadow: none;
}

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

/* Button Sizes */
.btn-sm {
    padding: var(--spacing-sm) var(--spacing-lg);
    font-size: var(--font-size-base);
}

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

/* Button Block */
.btn-block {
    display: block;
    width: 100%;
}

/* Disabled Button */
.btn:disabled,
.btn.disabled {
    opacity: var(--opacity-disabled);
    cursor: not-allowed;
    pointer-events: none;
}

/* ============================================
   FORM ELEMENTS
   ============================================ */

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

.form-label {
    display: block;
    margin-bottom: var(--spacing-sm);
    color: var(--color-gray-700);
    font-weight: var(--font-weight-medium);
}

.form-control {
    width: 100%;
    padding: 12px 20px;
    font-size: var(--font-size-base);
    font-family: var(--font-family-base);
    color: var(--color-text-dark);
    background: var(--color-white);
    border: 2px solid var(--color-border);
    border-radius: var(--radius-lg);
    transition: border-color var(--transition-base);
}

.form-control:focus {
    outline: none;
    border-color: var(--color-primary-blue);
    box-shadow: 0 0 0 3px rgba(78, 95, 229, 0.1);
}

.form-control:disabled {
    background: var(--color-gray-50);
    cursor: not-allowed;
    opacity: var(--opacity-disabled);
}

textarea.form-control {
    min-height: 120px;
    resize: vertical;
}

/* ============================================
   CARDS & CONTAINERS
   ============================================ */

.card {
    background: var(--color-white);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-card);
    border: 1px solid rgba(0,0,0,0.02);
    overflow: hidden;
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-hover);
}

.card-header {
    padding: var(--spacing-lg);
    background: var(--color-gray-50);
    border-bottom: 1px solid var(--color-border);
}

.card-body {
    padding: var(--spacing-lg);
}

.card-footer {
    padding: var(--spacing-lg);
    background: var(--color-gray-50);
    border-top: 1px solid var(--color-gray-200);
}

/* Container */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-lg);
    width: 100%;
}

.container-fluid {
    width: 100%;
    padding: 0 var(--spacing-lg);
}

/* Header Section */
.header {
    background: var(--color-white);
    border-radius: var(--radius-lg);
    padding: 30px;
    margin-bottom: 30px;
    box-shadow: var(--shadow-card);
    border: 1px solid rgba(0,0,0,0.02);
    transition: transform var(--transition-base);
}

.header:hover {
    transform: translateY(-5px);
}

.header h1 {
    color: var(--color-text-dark);
    margin-bottom: 10px;
    font-weight: 600;
}

.header h1 i {
    color: var(--color-primary-blue);
}

.header p {
    color: var(--color-text-medium);
    font-size: 1.1em;
}

.btn-group {
    display: flex;
    gap: 15px;
    margin-top: 20px;
    flex-wrap: wrap;
}

/* Content Section */
.content-section {
    background: var(--color-white);
    border-radius: var(--radius-lg);
    padding: 30px;
    margin-bottom: 20px;
    box-shadow: var(--shadow-card);
    border: 1px solid rgba(0,0,0,0.02);
}

.content-section h2 {
    color: var(--color-text-dark);
    margin-bottom: 20px;
    font-weight: 600;
    display: flex;
    align-items: center;
    gap: 10px;
}

.content-section h2 i {
    color: var(--color-primary-blue);
}

/* ============================================
   GRID SYSTEM
   ============================================ */

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

.grid-cols-2 {
    grid-template-columns: repeat(2, 1fr);
}

.grid-cols-3 {
    grid-template-columns: repeat(3, 1fr);
}

.grid-cols-4 {
    grid-template-columns: repeat(4, 1fr);
}

.grid-auto-fill {
    grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
}

.grid-auto-fit {
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
}

/* ============================================
   FLEXBOX UTILITIES
   ============================================ */

.flex {
    display: flex;
}

.flex-row {
    flex-direction: row;
}

.flex-col {
    flex-direction: column;
}

.flex-wrap {
    flex-wrap: wrap;
}

.flex-center {
    justify-content: center;
    align-items: center;
}

.justify-start {
    justify-content: flex-start;
}

.justify-center {
    justify-content: center;
}

.justify-end {
    justify-content: flex-end;
}

.justify-between {
    justify-content: space-between;
}

.justify-around {
    justify-content: space-around;
}

.items-start {
    align-items: flex-start;
}

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

.items-end {
    align-items: flex-end;
}

.flex-1 {
    flex: 1;
}

/* ============================================
   SPACING UTILITIES
   ============================================ */

/* Margin */
.m-0 { margin: 0; }
.m-xs { margin: var(--spacing-xs); }
.m-sm { margin: var(--spacing-sm); }
.m-md { margin: var(--spacing-md); }
.m-lg { margin: var(--spacing-lg); }
.m-xl { margin: var(--spacing-xl); }

.mt-0 { margin-top: 0; }
.mt-xs { margin-top: var(--spacing-xs); }
.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-0 { margin-bottom: 0; }
.mb-xs { margin-bottom: var(--spacing-xs); }
.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); }

/* Padding */
.p-0 { padding: 0; }
.p-xs { padding: var(--spacing-xs); }
.p-sm { padding: var(--spacing-sm); }
.p-md { padding: var(--spacing-md); }
.p-lg { padding: var(--spacing-lg); }
.p-xl { padding: var(--spacing-xl); }

.pt-0 { padding-top: 0; }
.pt-xs { padding-top: var(--spacing-xs); }
.pt-sm { padding-top: var(--spacing-sm); }
.pt-md { padding-top: var(--spacing-md); }
.pt-lg { padding-top: var(--spacing-lg); }
.pt-xl { padding-top: var(--spacing-xl); }

.pb-0 { padding-bottom: 0; }
.pb-xs { padding-bottom: var(--spacing-xs); }
.pb-sm { padding-bottom: var(--spacing-sm); }
.pb-md { padding-bottom: var(--spacing-md); }
.pb-lg { padding-bottom: var(--spacing-lg); }
.pb-xl { padding-bottom: var(--spacing-xl); }

/* Margin Right */
.mr-0 { margin-right: 0; }
.mr-xs { margin-right: var(--spacing-xs); }
.mr-sm { margin-right: var(--spacing-sm); }
.mr-md { margin-right: var(--spacing-md); }
.mr-lg { margin-right: var(--spacing-lg); }

/* Margin Left */
.ml-0 { margin-left: 0; }
.ml-xs { margin-left: var(--spacing-xs); }
.ml-sm { margin-left: var(--spacing-sm); }
.ml-md { margin-left: var(--spacing-md); }
.ml-lg { margin-left: var(--spacing-lg); }

/* Padding Left */
.pl-0 { padding-left: 0; }
.pl-xs { padding-left: var(--spacing-xs); }
.pl-sm { padding-left: var(--spacing-sm); }
.pl-md { padding-left: var(--spacing-md); }
.pl-lg { padding-left: var(--spacing-lg); }

/* Padding Right */
.pr-0 { padding-right: 0; }
.pr-xs { padding-right: var(--spacing-xs); }
.pr-sm { padding-right: var(--spacing-sm); }
.pr-md { padding-right: var(--spacing-md); }
.pr-lg { padding-right: var(--spacing-lg); }

/* ============================================
   TEXT UTILITIES
   ============================================ */

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

.text-xs { font-size: var(--font-size-xs); }
.text-sm { font-size: var(--font-size-sm); }
.text-base { font-size: var(--font-size-base); }
.text-lg { font-size: var(--font-size-lg); }
.text-xl { font-size: var(--font-size-xl); }
.text-2xl { font-size: var(--font-size-2xl); }
.text-3xl { font-size: var(--font-size-3xl); }

.font-normal { font-weight: var(--font-weight-normal); }
.font-medium { font-weight: var(--font-weight-medium); }
.font-semibold { font-weight: var(--font-weight-semibold); }
.font-bold { font-weight: var(--font-weight-bold); }

.text-primary { color: var(--color-primary-blue); }
.text-coral { color: var(--color-accent-coral); }
.text-lavender { color: var(--color-accent-lavender); }
.text-yellow { color: var(--color-accent-yellow); }
.text-dark { color: var(--color-text-dark); }
.text-medium { color: var(--color-text-medium); }
.text-light { color: var(--color-text-light); }
.text-muted { color: var(--color-text-light); }
.text-white { color: var(--color-white); }

/* ============================================
   BACKGROUND UTILITIES
   ============================================ */

.bg-primary { background-color: var(--color-primary-blue); }
.bg-coral { background-color: var(--color-accent-coral); }
.bg-lavender { background-color: var(--color-accent-lavender); }
.bg-yellow { background-color: var(--color-accent-yellow); }
.bg-white { background-color: var(--color-white); }
.bg-light-gray { background-color: var(--color-bg-light-gray); }
.bg-soft-pink { background-color: var(--color-bg-soft-pink); }
.bg-light-blue { background-color: var(--color-bg-light-blue); }
.bg-gray-50 { background-color: var(--color-gray-50); }
.bg-gray-100 { background-color: var(--color-gray-100); }
.bg-gray-200 { background-color: var(--color-gray-200); }

/* ============================================
   BORDER UTILITIES
   ============================================ */

.border { border: 1px solid var(--color-border); }
.border-0 { border: 0; }
.border-gray-200 { border-color: var(--color-gray-200); }
.border-gray-300 { border-color: var(--color-gray-300); }
.border-primary { border-color: var(--color-primary); }
.border-dashed { border-style: dashed; }

.rounded-sm { border-radius: var(--radius-sm); }
.rounded-md { border-radius: var(--radius-md); }
.rounded-lg { border-radius: var(--radius-lg); }
.rounded-xl { border-radius: var(--radius-xl); }
.rounded-2xl { border-radius: var(--radius-2xl); }
.rounded-full { border-radius: var(--radius-full); }
.rounded-circle { border-radius: var(--radius-circle); }

/* ============================================
   SHADOW UTILITIES
   ============================================ */

.shadow-sm { box-shadow: var(--shadow-sm); }
.shadow-md { box-shadow: var(--shadow-md); }
.shadow-lg { box-shadow: var(--shadow-lg); }
.shadow-xl { box-shadow: var(--shadow-xl); }
.shadow-none { box-shadow: none; }

/* ============================================
   DISPLAY UTILITIES
   ============================================ */

.d-none { display: none; }
.d-block { display: block; }
.d-inline { display: inline; }
.d-inline-block { display: inline-block; }
.d-flex { display: flex; }
.d-grid { display: grid; }

/* ============================================
   POSITION UTILITIES
   ============================================ */

.position-relative { position: relative; }
.position-absolute { position: absolute; }
.position-fixed { position: fixed; }
.position-sticky { position: sticky; }

/* ============================================
   VISIBILITY UTILITIES
   ============================================ */

.hidden { display: none; }
.visible { display: block; }
.invisible { visibility: hidden; }

/* ============================================
   ALERTS & NOTIFICATIONS
   ============================================ */

.alert {
    padding: var(--spacing-md);
    border-radius: var(--radius-md);
    margin-bottom: var(--spacing-md);
}

.alert-success {
    background-color: var(--color-success-bg);
    color: var(--color-success);
    border-left: 4px solid var(--color-success);
}

.alert-error {
    background-color: var(--color-error-bg);
    color: var(--color-error);
    border-left: 4px solid var(--color-error);
}

.alert-warning {
    background-color: var(--color-warning-bg);
    color: var(--color-warning);
    border-left: 4px solid var(--color-warning);
}

.alert-info {
    background-color: var(--color-info-bg);
    color: var(--color-info);
    border-left: 4px solid var(--color-info);
}

/* ============================================
   BADGE
   ============================================ */

.badge {
    display: inline-block;
    padding: var(--spacing-xs) var(--spacing-sm);
    font-size: var(--font-size-xs);
    font-weight: var(--font-weight-semibold);
    border-radius: var(--radius-sm);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

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

.badge-coral {
    background: var(--color-accent-coral);
    color: var(--color-white);
}

.badge-yellow {
    background: var(--color-accent-yellow);
    color: var(--color-text-dark);
}

.badge-success {
    background: var(--color-success);
    color: var(--color-white);
}

.badge-error {
    background: var(--color-error);
    color: var(--color-white);
}

/* ============================================
   MODAL
   ============================================ */

.modal {
    display: none;
    position: fixed;
    z-index: var(--z-modal-backdrop);
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    overflow: auto;
    background-color: rgba(0,0,0,0.5);
    animation: fadeIn 0.3s;
}

.modal-content {
    background-color: var(--color-white);
    margin: 50px auto;
    padding: 0;
    border-radius: var(--radius-lg);
    width: 95%;
    max-width: 1200px;
    box-shadow: var(--shadow-hover);
    animation: slideDown 0.3s;
    z-index: var(--z-modal);
}

@keyframes slideDown {
    from { transform: translateY(-50px); opacity: 0; }
    to { transform: translateY(0); opacity: 1; }
}

.modal-header {
    padding: 25px 30px;
    border-bottom: 2px solid var(--color-bg-light-gray);
    display: flex;
    justify-content: space-between;
    align-items: center;
    background: var(--color-bg-light-blue);
    border-radius: var(--radius-lg) var(--radius-lg) 0 0;
}

.modal-header h2 {
    color: var(--color-text-dark);
    margin: 0;
    font-weight: 600;
}

.modal-body {
    padding: 30px;
    max-height: 70vh;
    overflow-y: auto;
}

.modal-footer {
    padding: 20px 30px;
    border-top: 2px solid var(--color-bg-light-gray);
    display: flex;
    justify-content: flex-end;
    gap: 10px;
    background: var(--color-bg-light-gray);
    border-radius: 0 0 var(--radius-lg) var(--radius-lg);
}

.close {
    color: var(--color-text-medium);
    font-size: 32px;
    font-weight: bold;
    cursor: pointer;
    transition: color var(--transition-base);
    line-height: 1;
}

.close:hover {
    color: var(--color-accent-coral);
}

/* Button Variants */
.btn-cancel {
    padding: 12px 24px;
    background: var(--color-text-medium);
    color: var(--color-white);
    border: none;
    border-radius: var(--radius-md);
    cursor: pointer;
    font-weight: 600;
    transition: all var(--transition-base);
    font-family: var(--font-family-base);
}

.btn-cancel:hover {
    transform: translateY(-2px);
    background: var(--color-gray-600);
}

.btn-save {
    padding: 14px 32px;
    background: var(--color-primary-blue);
    color: var(--color-white);
    border: none;
    border-radius: var(--radius-md);
    cursor: pointer;
    font-weight: 600;
    transition: all var(--transition-base);
    box-shadow: var(--shadow-button-blue);
    font-family: var(--font-family-base);
}

.btn-save:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-button-blue-hover);
}

.btn-edit {
    background: var(--color-success-green);
    color: var(--color-white);
    box-shadow: 0 4px 12px rgba(74, 210, 149, 0.3);
}

.btn-edit:hover {
    box-shadow: 0 6px 20px rgba(74, 210, 149, 0.4);
}

.btn-delete {
    background: var(--color-accent-coral);
    color: var(--color-white);
    box-shadow: var(--shadow-button-coral);
}

.btn-delete:hover {
    box-shadow: var(--shadow-button-coral-hover);
}

.btn-assign {
    background: var(--color-accent-lavender);
    color: var(--color-text-dark);
    box-shadow: 0 4px 12px rgba(165, 180, 252, 0.3);
}

.btn-assign:hover {
    box-shadow: 0 6px 20px rgba(165, 180, 252, 0.4);
    color: var(--color-text-dark);
}

.btn-add-word {
    padding: 10px 20px;
    background: var(--color-success-green);
    color: var(--color-white);
    border: none;
    border-radius: var(--radius-md);
    cursor: pointer;
    font-weight: 600;
    transition: all var(--transition-base);
    box-shadow: 0 4px 12px rgba(74, 210, 149, 0.3);
    font-family: var(--font-family-base);
}

.btn-add-word:hover:not(:disabled) {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(74, 210, 149, 0.4);
}

.btn-add-word:disabled,
.btn:disabled {
    background: var(--color-text-light) !important;
    cursor: not-allowed !important;
    opacity: 0.6;
    box-shadow: none !important;
}

.btn-remove {
    padding: 10px 15px;
    background: var(--color-accent-coral);
    color: var(--color-white);
    border: none;
    border-radius: var(--radius-md);
    cursor: pointer;
    font-weight: 600;
    transition: all var(--transition-base);
    box-shadow: var(--shadow-button-coral);
    font-family: var(--font-family-base);
}

.btn-remove:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-button-coral-hover);
}

.btn-small {
    padding: 8px 16px;
    font-size: 13px;
    border-radius: var(--radius-md);
}

/* Empty State */
.empty-state {
    text-align: center;
    padding: 60px 20px;
    color: var(--color-text-medium);
}

.empty-state .icon {
    font-size: 4em;
    margin-bottom: 20px;
    opacity: 0.5;
    color: var(--color-accent-lavender);
}

/* ============================================
   LOADING SPINNER
   ============================================ */

.spinner {
    border: 3px solid var(--color-gray-200);
    border-top: 3px solid var(--color-primary-blue);
    border-radius: var(--radius-circle);
    width: 40px;
    height: 40px;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

.spinner-sm {
    width: 20px;
    height: 20px;
    border-width: 2px;
}

.spinner-lg {
    width: 60px;
    height: 60px;
    border-width: 4px;
}

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

/* Mobile First Approach */
@media (max-width: 768px) {
    .container {
        padding: 0 var(--spacing-md);
    }

    .grid-cols-2,
    .grid-cols-3,
    .grid-cols-4 {
        grid-template-columns: 1fr;
    }

    h1 {
        font-size: var(--font-size-2xl);
    }

    h2 {
        font-size: var(--font-size-xl);
    }

    .btn {
        padding: var(--spacing-sm) var(--spacing-lg);
        font-size: var(--font-size-base);
    }

    .hide-mobile {
        display: none !important;
    }
}

@media (min-width: 769px) {
    .hide-desktop {
        display: none !important;
    }
}

/* Tablet Breakpoint */
@media (min-width: 768px) and (max-width: 1024px) {
    .grid-cols-4 {
        grid-template-columns: repeat(2, 1fr);
    }
}

/* Desktop Breakpoint */
@media (min-width: 1024px) {
    .container {
        max-width: 1200px;
    }
}

/* ============================================
   PRINT STYLES
   ============================================ */

@media print {
    body {
        background: white;
        color: black;
    }

    .no-print {
        display: none !important;
    }

    .card {
        box-shadow: none;
        border: 1px solid var(--color-gray-300);
    }
}

/* ============================================
   ACCESSIBILITY
   ============================================ */

/* Focus Visible */
:focus-visible {
    outline: 2px solid var(--color-primary-blue);
    outline-offset: 2px;
}

/* Reduce Motion */
@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}

/* High Contrast Mode Support */
@media (prefers-contrast: high) {
    .btn {
        border: 2px solid currentColor;
    }
}

/* ============================================
   CUSTOM SCROLLBAR
   ============================================ */

::-webkit-scrollbar {
    width: 12px;
}

::-webkit-scrollbar-track {
    background: var(--color-gray-100);
}

::-webkit-scrollbar-thumb {
    background: var(--color-gray-400);
    border-radius: var(--radius-sm);
}

::-webkit-scrollbar-thumb:hover {
    background: var(--color-gray-600);
}

/* ============================================
   VOCABULARY DASHBOARD COMPONENTS
   ============================================ */

/* Dashboard Banner (Welcome Banner) */
.dashboard-banner {
    background-color: var(--color-bg-soft-pink);
    border-radius: var(--radius-lg);
    padding: 40px;
    position: relative;
    overflow: hidden;
    margin-bottom: 40px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 20px;
}

.dashboard-banner::before {
    content: '';
    position: absolute;
    top: -50px;
    left: -50px;
    width: 200px;
    height: 200px;
    background: rgba(255, 255, 255, 0.4);
    border-radius: 50%;
    pointer-events: none;
}

.banner-content h1 {
    color: var(--color-accent-coral);
    font-size: 28px;
    font-weight: 700;
    margin-bottom: 10px;
}

.banner-content p {
    color: #A3585A;
    max-width: 500px;
    margin: 0;
}

.banner-actions {
    display: flex;
    gap: 15px;
    z-index: 2;
    flex-wrap: wrap;
}

/* Section Headers */
.section-wrapper {
    margin-bottom: var(--spacing-xl);
}

.section-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
    padding: 0 5px;
}

.section-header h2 {
    font-size: 18px;
    font-weight: 700;
    color: var(--color-text-dark);
    margin: 0;
}

.section-header a {
    font-size: 13px;
    color: var(--color-text-medium);
    font-weight: 600;
    text-decoration: none;
    transition: color var(--transition-base);
}

.section-header a:hover {
    color: var(--color-primary);
}

/* Action Button */
.btn-action {
    background: var(--color-bg-soft-blue);
    color: var(--color-primary);
    font-weight: 600;
}

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

/* Utility: Margin Left Extra Small */
.ml-xs {
    margin-left: var(--spacing-xs);
}

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

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

/* Utility: Display None */
.d-none {
    display: none;
}

/* Text Colors */
.text-coral {
    color: var(--color-accent-coral);
}

.text-purple {
    color: var(--color-accent-purple);
}

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

/* Background Utilities */
.bg-pink {
    background-color: var(--color-bg-soft-pink);
}

.bg-light-gray {
    background-color: var(--color-bg-light-gray);
}

/* Flexbox Utilities */
.flex-1 {
    flex: 1;
}

.cursor-pointer {
    cursor: pointer;
}

/* Rounded */
.rounded-md {
    border-radius: var(--radius-md);
}

.rounded-lg {
    border-radius: var(--radius-lg);
}

/* Border None */
.border-none {
    border: none !important;
}

/* Gap Utilities */
.gap-sm {
    gap: var(--spacing-sm);
}

.gap-md {
    gap: var(--spacing-md);
}

.gap-lg {
    gap: var(--spacing-lg);
}

/* Margin/Padding Zero */
.m-0 {
    margin: 0 !important;
}

.p-md {
    padding: var(--spacing-md);
}

/* Display Flex with Utilities */
.d-flex {
    display: flex;
}

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

.justify-between {
    justify-content: space-between;
}

.flex-wrap {
    flex-wrap: wrap;
}

/* Grid Utilities */
.grid {
    display: grid;
}

.grid-cols-2 {
    grid-template-columns: repeat(2, 1fr);
}

.grid-auto-fill {
    grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
}

/* Text Sizes */
.text-xs {
    font-size: var(--font-size-xs);
}

.text-sm {
    font-size: var(--font-size-sm);
}

.text-md {
    font-size: var(--font-size-base);
}

.text-lg {
    font-size: var(--font-size-lg);
}

.text-xl {
    font-size: var(--font-size-xl);
}

/* Font Weight */
.font-semibold {
    font-weight: var(--font-weight-semibold);
}

.font-bold {
    font-weight: var(--font-weight-bold);
}

/* Spacing Utilities */
.mt-xs {
    margin-top: var(--spacing-xs);
}

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

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

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

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

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

/* Alert Styles */
.alert {
    padding: 15px 20px;
    border-radius: var(--radius-md);
    margin-bottom: var(--spacing-md);
    font-size: 14px;
}

.alert-error {
    background-color: var(--color-bg-soft-pink);
    color: var(--color-accent-coral);
    border-left: 4px solid var(--color-accent-coral);
}

.alert-success {
    background-color: rgba(74, 210, 149, 0.15);
    color: var(--color-success-green);
    border-left: 4px solid var(--color-success-green);
}

/* Form Label */
.form-label {
    display: block;
    margin-bottom: var(--spacing-sm);
    color: var(--color-text-dark);
    font-weight: 500;
    font-size: var(--font-size-sm);
}