/* ============================================================
   KidZaps - Design System
   A modern, vibrant, kid-friendly design with premium feel
   ============================================================ */

/* ---------- CSS Custom Properties (Design Tokens) ---------- */
:root {
    /* Primary Colors - Vibrant Purple/Blue */
    --color-primary: #6366F1;
    --color-primary-light: #818CF8;
    --color-primary-dark: #4F46E5;
    --color-primary-50: #EEF2FF;
    --color-primary-100: #E0E7FF;

    /* Accent Colors */
    --color-accent: #F59E0B;
    --color-accent-light: #FCD34D;
    --color-accent-dark: #D97706;

    /* Success / Reward */
    --color-success: #10B981;
    --color-success-light: #6EE7B7;

    /* Danger */
    --color-danger: #EF4444;
    --color-danger-light: #FCA5A5;

    /* Neutrals */
    --color-gray-50: #F9FAFB;
    --color-gray-100: #F3F4F6;
    --color-gray-200: #E5E7EB;
    --color-gray-300: #D1D5DB;
    --color-gray-400: #9CA3AF;
    --color-gray-500: #6B7280;
    --color-gray-600: #4B5563;
    --color-gray-700: #374151;
    --color-gray-800: #1F2937;
    --color-gray-900: #111827;

    /* Category Card Colors (rainbow palette) */
    --cat-red: #EF4444;
    --cat-orange: #F97316;
    --cat-amber: #F59E0B;
    --cat-lime: #84CC16;
    --cat-green: #22C55E;
    --cat-teal: #14B8A6;
    --cat-cyan: #06B6D4;
    --cat-blue: #3B82F6;
    --cat-indigo: #6366F1;
    --cat-violet: #8B5CF6;
    --cat-purple: #A855F7;
    --cat-fuchsia: #D946EF;
    --cat-pink: #EC4899;
    --cat-rose: #F43F5E;

    /* Typography */
    --font-primary: 'Nunito', 'Segoe UI', system-ui, -apple-system, sans-serif;
    --font-heading: 'Fredoka', 'Nunito', sans-serif;
    --font-mono: 'JetBrains Mono', 'Fira Code', monospace;

    /* Font Sizes */
    --text-xs: 0.75rem;
    --text-sm: 0.875rem;
    --text-base: 1rem;
    --text-lg: 1.125rem;
    --text-xl: 1.25rem;
    --text-2xl: 1.5rem;
    --text-3xl: 1.875rem;
    --text-4xl: 2.25rem;
    --text-5xl: 3rem;

    /* Spacing */
    --space-1: 0.25rem;
    --space-2: 0.5rem;
    --space-3: 0.75rem;
    --space-4: 1rem;
    --space-5: 1.25rem;
    --space-6: 1.5rem;
    --space-8: 2rem;
    --space-10: 2.5rem;
    --space-12: 3rem;
    --space-16: 4rem;
    --space-20: 5rem;

    /* Border Radius */
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    --radius-2xl: 1.5rem;
    --radius-full: 9999px;

    /* Shadows */
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.07), 0 2px 4px -2px rgba(0, 0, 0, 0.05);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.08), 0 4px 6px -4px rgba(0, 0, 0, 0.04);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 8px 10px -6px rgba(0, 0, 0, 0.04);
    --shadow-glow: 0 0 20px rgba(99, 102, 241, 0.15);
    --shadow-card: 0 2px 8px rgba(0, 0, 0, 0.06), 0 0 1px rgba(0, 0, 0, 0.1);
    --shadow-card-hover: 0 12px 24px rgba(0, 0, 0, 0.12), 0 0 1px rgba(0, 0, 0, 0.1);

    /* Transitions */
    --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-normal: 250ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 350ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-bounce: 500ms cubic-bezier(0.34, 1.56, 0.64, 1);

    /* Layout */
    --container-max: 1280px;
    --sidebar-width: 300px;
    --header-height: 70px;
}

/* ---------- Reset & Base ---------- */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    scroll-behavior: smooth;
    -webkit-text-size-adjust: 100%;
    font-size: 16px;
}

body {
    font-family: var(--font-primary);
    font-size: var(--text-base);
    line-height: 1.6;
    color: var(--color-gray-800);
    background-color: var(--color-gray-50);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    overflow-x: hidden;
}

/* ---------- Typography ---------- */
h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-heading);
    font-weight: 700;
    line-height: 1.3;
    color: var(--color-gray-900);
}

h1 { font-size: var(--text-4xl); }
h2 { font-size: var(--text-3xl); }
h3 { font-size: var(--text-2xl); }
h4 { font-size: var(--text-xl); }
h5 { font-size: var(--text-lg); }

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

a:hover {
    color: var(--color-primary-dark);
}

img {
    max-width: 100%;
    height: auto;
    display: block;
}

/* ---------- Container ---------- */
.container {
    width: 100%;
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 var(--space-6);
}

/* ---------- Header ---------- */
.site-header {
    background: white;
    border-bottom: 1px solid var(--color-gray-200);
    position: sticky;
    top: 0;
    z-index: 1000;
    height: var(--header-height);
    box-shadow: var(--shadow-sm);
}

.header-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 100%;
    gap: var(--space-6);
}

.site-logo {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    font-family: var(--font-heading);
    font-size: var(--text-2xl);
    font-weight: 800;
    color: var(--color-primary);
    text-decoration: none;
    flex-shrink: 0;
}

.site-logo img {
    height: 40px;
    width: auto;
}

.site-logo .logo-text {
    background: linear-gradient(135deg, var(--color-primary), var(--color-accent));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

/* Main Navigation */
.main-nav {
    display: flex;
    align-items: center;
    gap: var(--space-1);
}

.main-nav a {
    padding: var(--space-2) var(--space-4);
    border-radius: var(--radius-lg);
    color: var(--color-gray-600);
    font-weight: 600;
    font-size: var(--text-sm);
    transition: all var(--transition-fast);
    white-space: nowrap;
}

.main-nav a:hover,
.main-nav a.active {
    color: var(--color-primary);
    background: var(--color-primary-50);
}

/* Search Bar */
.header-search {
    position: relative;
    flex: 0 1 320px;
}

.header-search input {
    width: 100%;
    padding: var(--space-2) var(--space-4);
    padding-left: 2.5rem;
    border: 2px solid var(--color-gray-200);
    border-radius: var(--radius-full);
    font-size: var(--text-sm);
    font-family: var(--font-primary);
    background: var(--color-gray-50);
    transition: all var(--transition-fast);
    outline: none;
}

.header-search input:focus {
    border-color: var(--color-primary-light);
    background: white;
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.1);
}

.header-search .search-icon {
    position: absolute;
    left: 0.875rem;
    top: 50%;
    transform: translateY(-50%);
    color: var(--color-gray-400);
    width: 16px;
    height: 16px;
}

/* Locale Switcher */
.locale-switcher {
    display: flex;
    align-items: center;
    gap: var(--space-1);
    background: var(--color-gray-100);
    border-radius: var(--radius-full);
    padding: var(--space-1);
}

.locale-switcher a {
    padding: var(--space-1) var(--space-3);
    border-radius: var(--radius-full);
    font-size: var(--text-xs);
    font-weight: 700;
    color: var(--color-gray-500);
    transition: all var(--transition-fast);
}

.locale-switcher a.active {
    background: white;
    color: var(--color-primary);
    box-shadow: var(--shadow-sm);
}

/* Mobile menu toggle */
.mobile-menu-btn {
    display: none;
    background: none;
    border: none;
    padding: var(--space-2);
    cursor: pointer;
    color: var(--color-gray-600);
}

/* ---------- Hero Section ---------- */
.hero {
    background: linear-gradient(135deg, #667EEA 0%, #764BA2 100%);
    padding: var(--space-16) 0 var(--space-20);
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: -50%;
    right: -20%;
    width: 600px;
    height: 600px;
    background: rgba(255, 255, 255, 0.08);
    border-radius: 50%;
    animation: float 6s ease-in-out infinite;
}

.hero::after {
    content: '';
    position: absolute;
    bottom: -30%;
    left: -10%;
    width: 400px;
    height: 400px;
    background: rgba(255, 255, 255, 0.05);
    border-radius: 50%;
    animation: float 8s ease-in-out infinite reverse;
}

@keyframes float {
    0%, 100% { transform: translateY(0) rotate(0deg); }
    50% { transform: translateY(-20px) rotate(5deg); }
}

.hero-content {
    position: relative;
    z-index: 1;
    text-align: center;
    color: white;
}

.hero h1 {
    color: white;
    font-size: var(--text-5xl);
    margin-bottom: var(--space-4);
    text-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

.hero p {
    font-size: var(--text-xl);
    opacity: 0.9;
    max-width: 600px;
    margin: 0 auto var(--space-8);
}

.hero-search {
    max-width: 500px;
    margin: 0 auto;
    position: relative;
}

.hero-search input {
    width: 100%;
    padding: var(--space-4) var(--space-6);
    padding-right: 120px;
    border: none;
    border-radius: var(--radius-full);
    font-size: var(--text-lg);
    font-family: var(--font-primary);
    box-shadow: var(--shadow-xl);
    outline: none;
}

.hero-search button {
    position: absolute;
    right: 6px;
    top: 50%;
    transform: translateY(-50%);
    padding: var(--space-3) var(--space-6);
    background: var(--color-primary);
    color: white;
    border: none;
    border-radius: var(--radius-full);
    font-family: var(--font-primary);
    font-weight: 700;
    font-size: var(--text-sm);
    cursor: pointer;
    transition: background var(--transition-fast);
}

.hero-search button:hover {
    background: var(--color-primary-dark);
}

/* ---------- Grade Filter Bar ---------- */
.grade-bar {
    background: white;
    border-bottom: 1px solid var(--color-gray-200);
    padding: var(--space-3) 0;
    position: sticky;
    top: var(--header-height);
    z-index: 999;
    box-shadow: var(--shadow-sm);
}

.grade-bar-inner {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    overflow-x: auto;
    scrollbar-width: none;
    -ms-overflow-style: none;
}

.grade-bar-inner::-webkit-scrollbar {
    display: none;
}

.grade-bar-label {
    font-weight: 700;
    color: var(--color-gray-500);
    font-size: var(--text-sm);
    white-space: nowrap;
    flex-shrink: 0;
}

.grade-pill {
    display: inline-flex;
    align-items: center;
    padding: var(--space-2) var(--space-4);
    border-radius: var(--radius-full);
    font-size: var(--text-sm);
    font-weight: 600;
    color: var(--color-gray-600);
    background: var(--color-gray-100);
    border: 2px solid transparent;
    text-decoration: none;
    white-space: nowrap;
    transition: all var(--transition-fast);
    cursor: pointer;
}

.grade-pill:hover {
    background: var(--color-primary-50);
    color: var(--color-primary);
    border-color: var(--color-primary-light);
}

.grade-pill.active {
    background: var(--color-primary);
    color: white;
    border-color: var(--color-primary);
}

/* ---------- Section Headings ---------- */
.section {
    padding: var(--space-12) 0;
}

.section-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: var(--space-8);
}

.section-title {
    font-size: var(--text-2xl);
    position: relative;
    padding-left: var(--space-4);
}

.section-title::before {
    content: '';
    position: absolute;
    left: 0;
    top: 50%;
    transform: translateY(-50%);
    width: 4px;
    height: 70%;
    background: linear-gradient(180deg, var(--color-primary), var(--color-accent));
    border-radius: var(--radius-full);
}

.section-link {
    font-size: var(--text-sm);
    font-weight: 600;
    color: var(--color-primary);
    display: flex;
    align-items: center;
    gap: var(--space-1);
}

/* ---------- Category Grid ---------- */
.category-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: var(--space-6);
}

.category-card {
    background: white;
    border-radius: var(--radius-xl);
    padding: var(--space-6);
    text-align: center;
    text-decoration: none;
    color: inherit;
    box-shadow: var(--shadow-card);
    transition: all var(--transition-normal);
    position: relative;
    overflow: hidden;
    border: 2px solid transparent;
}

.category-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: var(--card-color, var(--color-primary));
    transition: height var(--transition-normal);
}

.category-card:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow-card-hover);
    border-color: var(--card-color, var(--color-primary));
}

.category-card:hover::before {
    height: 6px;
}

.category-icon {
    width: 64px;
    height: 64px;
    margin: 0 auto var(--space-4);
    background: var(--card-color-light, var(--color-primary-50));
    border-radius: var(--radius-xl);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 28px;
    transition: transform var(--transition-bounce);
}

.category-card:hover .category-icon {
    transform: scale(1.1) rotate(-5deg);
}

.category-card h3 {
    font-size: var(--text-lg);
    margin-bottom: var(--space-2);
    font-family: var(--font-heading);
}

.category-card p {
    font-size: var(--text-sm);
    color: var(--color-gray-500);
    line-height: 1.5;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.category-count {
    display: inline-flex;
    align-items: center;
    gap: var(--space-1);
    margin-top: var(--space-3);
    padding: var(--space-1) var(--space-3);
    background: var(--color-gray-100);
    border-radius: var(--radius-full);
    font-size: var(--text-xs);
    font-weight: 600;
    color: var(--color-gray-500);
}

/* ---------- Worksheet Cards ---------- */
.worksheet-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: var(--space-6);
}

.worksheet-card {
    background: white;
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow-card);
    transition: all var(--transition-normal);
    text-decoration: none;
    color: inherit;
    display: flex;
    flex-direction: column;
}

.worksheet-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-card-hover);
}

.worksheet-thumb {
    width: 100%;
    aspect-ratio: 4/3;
    object-fit: cover;
    background: var(--color-gray-100);
    transition: transform var(--transition-slow);
}

.worksheet-card:hover .worksheet-thumb {
    transform: scale(1.05);
}

.worksheet-thumb-wrapper {
    overflow: hidden;
    position: relative;
}

.worksheet-badge {
    position: absolute;
    top: var(--space-3);
    left: var(--space-3);
    padding: var(--space-1) var(--space-3);
    border-radius: var(--radius-full);
    font-size: var(--text-xs);
    font-weight: 700;
    color: white;
    background: var(--color-primary);
}

.worksheet-info {
    padding: var(--space-4);
    flex: 1;
    display: flex;
    flex-direction: column;
}

.worksheet-info h4 {
    font-size: var(--text-base);
    margin-bottom: var(--space-2);
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.worksheet-meta {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    margin-top: auto;
    padding-top: var(--space-3);
    border-top: 1px solid var(--color-gray-100);
    font-size: var(--text-xs);
    color: var(--color-gray-400);
}

.worksheet-meta span {
    display: flex;
    align-items: center;
    gap: var(--space-1);
}

/* ---------- Buttons ---------- */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-2);
    padding: var(--space-3) var(--space-6);
    border: 2px solid transparent;
    border-radius: var(--radius-lg);
    font-family: var(--font-primary);
    font-size: var(--text-sm);
    font-weight: 700;
    text-decoration: none;
    cursor: pointer;
    transition: all var(--transition-fast);
    outline: none;
    white-space: nowrap;
}

.btn:focus-visible {
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.3);
}

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

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

.btn-secondary {
    background: var(--color-gray-100);
    color: var(--color-gray-700);
}

.btn-secondary:hover {
    background: var(--color-gray-200);
}

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

.btn-accent:hover {
    background: var(--color-accent-dark);
}

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

.btn-danger {
    background: var(--color-danger);
    color: white;
}

.btn-outline {
    background: transparent;
    border-color: var(--color-gray-300);
    color: var(--color-gray-700);
}

.btn-outline:hover {
    border-color: var(--color-primary);
    color: var(--color-primary);
    background: var(--color-primary-50);
}

.btn-sm {
    padding: var(--space-1) var(--space-3);
    font-size: var(--text-xs);
}

.btn-lg {
    padding: var(--space-4) var(--space-8);
    font-size: var(--text-base);
}

.btn-icon {
    padding: var(--space-2);
    border-radius: var(--radius-md);
}

/* ---------- Pagination ---------- */
.pagination {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-2);
    margin-top: var(--space-10);
}

.pagination a,
.pagination span {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    border-radius: var(--radius-lg);
    font-size: var(--text-sm);
    font-weight: 600;
    color: var(--color-gray-600);
    background: white;
    border: 1px solid var(--color-gray-200);
    text-decoration: none;
    transition: all var(--transition-fast);
}

.pagination a:hover {
    background: var(--color-primary-50);
    border-color: var(--color-primary-light);
    color: var(--color-primary);
}

.pagination .active {
    background: var(--color-primary);
    color: white;
    border-color: var(--color-primary);
}

/* ---------- Breadcrumb ---------- */
.breadcrumb-nav {
    padding: var(--space-4) 0;
}

.breadcrumb {
    display: flex;
    align-items: center;
    gap: var(--space-2);
    list-style: none;
    font-size: var(--text-sm);
    color: var(--color-gray-400);
}

.breadcrumb-item + .breadcrumb-item::before {
    content: '›';
    margin-right: var(--space-2);
    color: var(--color-gray-300);
}

.breadcrumb-item a {
    color: var(--color-gray-500);
}

.breadcrumb-item a:hover {
    color: var(--color-primary);
}

.breadcrumb-item.active {
    color: var(--color-gray-700);
    font-weight: 600;
}

/* ---------- Footer ---------- */
.site-footer {
    background: var(--color-gray-900);
    color: var(--color-gray-300);
    padding: var(--space-16) 0 var(--space-8);
    margin-top: var(--space-16);
}

.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: var(--space-10);
    margin-bottom: var(--space-10);
}

.footer-brand .logo-text {
    font-family: var(--font-heading);
    font-size: var(--text-2xl);
    font-weight: 800;
    color: white;
    margin-bottom: var(--space-3);
}

.footer-brand p {
    font-size: var(--text-sm);
    line-height: 1.8;
    color: var(--color-gray-400);
}

.footer-heading {
    color: white;
    font-size: var(--text-base);
    font-weight: 700;
    margin-bottom: var(--space-4);
}

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

.footer-links li {
    margin-bottom: var(--space-2);
}

.footer-links a {
    color: var(--color-gray-400);
    font-size: var(--text-sm);
    transition: color var(--transition-fast);
}

.footer-links a:hover {
    color: white;
}

.footer-bottom {
    border-top: 1px solid var(--color-gray-800);
    padding-top: var(--space-6);
    display: flex;
    align-items: center;
    justify-content: space-between;
    font-size: var(--text-sm);
    color: var(--color-gray-500);
}

.social-links {
    display: flex;
    gap: var(--space-3);
}

.social-links a {
    width: 36px;
    height: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: var(--radius-full);
    background: var(--color-gray-800);
    color: var(--color-gray-400);
    transition: all var(--transition-fast);
}

.social-links a:hover {
    background: var(--color-primary);
    color: white;
    transform: translateY(-2px);
}

/* ---------- Ad Slots ---------- */
.ad-slot {
    margin: var(--space-6) 0;
    text-align: center;
}

.ad-slot.ad-header {
    margin: var(--space-4) auto;
    max-width: 728px;
}

.ad-mobile-only { display: none; }
.ad-tablet-only { display: none; }
.ad-desktop-only { display: block; }

/* ---------- Worksheet Detail Page ---------- */
.worksheet-detail {
    display: grid;
    grid-template-columns: 1fr 300px;
    gap: var(--space-8);
    padding: var(--space-8) 0;
}

.worksheet-main {
    min-width: 0;
}

.worksheet-title {
    font-size: var(--text-3xl);
    margin-bottom: var(--space-4);
}

.worksheet-author-info {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    padding: var(--space-4);
    background: var(--color-gray-50);
    border-radius: var(--radius-lg);
    margin-bottom: var(--space-6);
}

.author-avatar {
    width: 48px;
    height: 48px;
    border-radius: var(--radius-full);
    object-fit: cover;
    background: var(--color-primary-100);
}

.author-name {
    font-weight: 700;
    color: var(--color-gray-900);
}

.author-role {
    font-size: var(--text-xs);
    color: var(--color-gray-500);
}

.worksheet-actions {
    display: flex;
    gap: var(--space-3);
    margin-bottom: var(--space-6);
    flex-wrap: wrap;
}

.worksheet-preview {
    background: white;
    border-radius: var(--radius-xl);
    padding: var(--space-6);
    box-shadow: var(--shadow-card);
    margin-bottom: var(--space-6);
}

.worksheet-tags {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-2);
    margin-top: var(--space-4);
}

.tag {
    padding: var(--space-1) var(--space-3);
    border-radius: var(--radius-full);
    background: var(--color-gray-100);
    color: var(--color-gray-600);
    font-size: var(--text-xs);
    font-weight: 600;
    text-decoration: none;
    transition: all var(--transition-fast);
}

.tag:hover {
    background: var(--color-primary-50);
    color: var(--color-primary);
}

/* ---------- Sidebar ---------- */
.sidebar {
    position: sticky;
    top: calc(var(--header-height) + 60px);
    align-self: start;
}

.sidebar-widget {
    background: white;
    border-radius: var(--radius-xl);
    padding: var(--space-5);
    box-shadow: var(--shadow-card);
    margin-bottom: var(--space-6);
}

.sidebar-widget h4 {
    font-size: var(--text-base);
    margin-bottom: var(--space-4);
    padding-bottom: var(--space-3);
    border-bottom: 2px solid var(--color-gray-100);
}

/* ---------- Reward Popup ---------- */
.reward-overlay {
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.5);
    backdrop-filter: blur(4px);
    z-index: 10000;
    display: none;
    align-items: center;
    justify-content: center;
    animation: fadeIn 0.3s ease;
}

.reward-overlay.active {
    display: flex;
}

.reward-popup {
    background: white;
    border-radius: var(--radius-2xl);
    padding: var(--space-10);
    text-align: center;
    max-width: 420px;
    width: 90%;
    box-shadow: var(--shadow-xl);
    animation: popIn 0.5s cubic-bezier(0.34, 1.56, 0.64, 1);
}

.reward-emoji {
    font-size: 4rem;
    margin-bottom: var(--space-4);
    animation: bounce 1s infinite;
}

.reward-message {
    font-family: var(--font-heading);
    font-size: var(--text-2xl);
    color: var(--color-primary);
    margin-bottom: var(--space-3);
}

.reward-stars {
    display: flex;
    justify-content: center;
    gap: var(--space-2);
    margin-bottom: var(--space-6);
    font-size: 1.5rem;
    color: var(--color-accent);
}

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

@keyframes popIn {
    from { transform: scale(0.5); opacity: 0; }
    to { transform: scale(1); opacity: 1; }
}

@keyframes bounce {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-10px); }
}

/* ---------- Hint Overlay ---------- */
.hint-overlay {
    position: absolute;
    inset: 0;
    pointer-events: none;
    z-index: 100;
    display: none;
}

.hint-overlay.active {
    display: block;
}

.hint-pulse {
    animation: hintPulse 1.5s ease-in-out infinite;
}

@keyframes hintPulse {
    0%, 100% { opacity: 0.3; transform: scale(1); }
    50% { opacity: 0.8; transform: scale(1.05); }
}

/* ---------- Flash Messages ---------- */
.flash-message {
    padding: var(--space-4) var(--space-6);
    border-radius: var(--radius-lg);
    margin-bottom: var(--space-6);
    font-weight: 600;
    display: flex;
    align-items: center;
    gap: var(--space-3);
    animation: slideDown 0.3s ease;
}

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

.flash-success {
    background: #ECFDF5;
    color: #065F46;
    border: 1px solid #A7F3D0;
}

.flash-error {
    background: #FEF2F2;
    color: #991B1B;
    border: 1px solid #FECACA;
}

.flash-info {
    background: #EFF6FF;
    color: #1E40AF;
    border: 1px solid #BFDBFE;
}

/* ---------- Forms ---------- */
.form-group {
    margin-bottom: var(--space-5);
}

.form-label {
    display: block;
    margin-bottom: var(--space-2);
    font-weight: 600;
    font-size: var(--text-sm);
    color: var(--color-gray-700);
}

.form-input,
.form-select,
.form-textarea {
    width: 100%;
    padding: var(--space-3) var(--space-4);
    border: 2px solid var(--color-gray-200);
    border-radius: var(--radius-lg);
    font-family: var(--font-primary);
    font-size: var(--text-sm);
    color: var(--color-gray-800);
    background: white;
    transition: all var(--transition-fast);
    outline: none;
}

.form-input:focus,
.form-select:focus,
.form-textarea:focus {
    border-color: var(--color-primary);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.1);
}

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

.form-checkbox {
    display: flex;
    align-items: center;
    gap: var(--space-2);
    cursor: pointer;
}

.form-checkbox input[type="checkbox"] {
    width: 18px;
    height: 18px;
    accent-color: var(--color-primary);
}

/* ---------- Utility Classes ---------- */
.text-center { text-align: center; }
.text-left { text-align: left; }
.text-right { text-align: right; }
.text-primary { color: var(--color-primary); }
.text-muted { color: var(--color-gray-500); }
.text-small { font-size: var(--text-sm); }
.text-xs { font-size: var(--text-xs); }
.fw-bold { font-weight: 700; }
.mt-4 { margin-top: var(--space-4); }
.mt-6 { margin-top: var(--space-6); }
.mt-8 { margin-top: var(--space-8); }
.mb-4 { margin-bottom: var(--space-4); }
.mb-6 { margin-bottom: var(--space-6); }
.mb-8 { margin-bottom: var(--space-8); }
.hidden { display: none !important; }
.flex { display: flex; }
.flex-center { display: flex; align-items: center; justify-content: center; }
.gap-2 { gap: var(--space-2); }
.gap-4 { gap: var(--space-4); }