/**
 * Learnillion Platform - Main Stylesheet
 * Brand Colors & Typography
 */

/* ============================================
   FONTS
   ============================================ */
@import url('https://fonts.googleapis.com/css2?family=Quicksand:wght@400;500;600;700&family=Inter:wght@400;500;600;700&display=swap');

/* ============================================
   CSS VARIABLES - BRAND COLORS
   ============================================ */
:root {
    /* Primary Colors */
    --color-primary: #2563EB;
    --color-primary-dark: #1E40AF;
    --color-primary-light: #60A5FA;
    
    --color-orange: #F97316;
    --color-orange-dark: #EA580C;
    --color-orange-light: #FB923C;
    
    --color-green: #10B981;
    --color-green-dark: #059669;
    --color-green-light: #34D399;
    
    --color-yellow: #FEF3C7;
    --color-yellow-dark: #FBBF24;
    
    /* Neutral Colors */
    --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;
    
    /* Semantic Colors */
    --color-success: #10B981;
    --color-error: #EF4444;
    --color-warning: #F59E0B;
    --color-info: #3B82F6;
    
    /* Typography */
    --font-heading: 'Quicksand', sans-serif;
    --font-body: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    
    /* Spacing */
    --spacing-xs: 4px;
    --spacing-sm: 8px;
    --spacing-md: 16px;
    --spacing-lg: 24px;
    --spacing-xl: 32px;
    --spacing-2xl: 48px;
    --spacing-3xl: 64px;
    
    /* Border Radius */
    --radius-sm: 4px;
    --radius-md: 8px;
    --radius-lg: 12px;
    --radius-xl: 16px;
    --radius-full: 9999px;
    
    /* Shadows */
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
    
    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-normal: 300ms ease;
    --transition-slow: 500ms ease;
}

/* ============================================
   RESET & BASE STYLES
   ============================================ */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-body);
    font-size: 16px;
    line-height: 1.6;
    color: var(--color-gray-800);
    background: var(--color-gray-50);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* ============================================
   TYPOGRAPHY
   ============================================ */
h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-heading);
    font-weight: 700;
    line-height: 1.2;
    color: var(--color-gray-900);
    margin-bottom: var(--spacing-md);
}

h1 { font-size: 3rem; }      /* 48px */
h2 { font-size: 2.25rem; }   /* 36px */
h3 { font-size: 1.875rem; }  /* 30px */
h4 { font-size: 1.5rem; }    /* 24px */
h5 { font-size: 1.25rem; }   /* 20px */
h6 { font-size: 1rem; }      /* 16px */

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

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

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

strong {
    font-weight: 600;
}

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

.container-narrow {
    max-width: 800px;
}

.container-wide {
    max-width: 1400px;
}

.section {
    padding: var(--spacing-3xl) 0;
}

.section-sm {
    padding: var(--spacing-2xl) 0;
}

/* ============================================
   BUTTONS
   ============================================ */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
    padding: 12px 24px;
    font-family: var(--font-body);
    font-size: 16px;
    font-weight: 600;
    line-height: 1;
    text-align: center;
    text-decoration: none;
    border: 2px solid transparent;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all var(--transition-normal);
    white-space: nowrap;
}

.btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

/* Button Variants */
.btn-primary {
    background: var(--color-primary);
    color: white;
    border-color: var(--color-primary);
}

.btn-primary:hover:not(:disabled) {
    background: var(--color-primary-dark);
    border-color: var(--color-primary-dark);
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

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

.btn-orange:hover:not(:disabled) {
    background: var(--color-orange-dark);
    border-color: var(--color-orange-dark);
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

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

.btn-outline:hover:not(:disabled) {
    background: var(--color-primary);
    color: white;
}

.btn-ghost {
    background: transparent;
    color: var(--color-primary);
    border-color: transparent;
}

.btn-ghost:hover:not(:disabled) {
    background: var(--color-gray-100);
}

/* Button Sizes */
.btn-sm {
    padding: 8px 16px;
    font-size: 14px;
}

.btn-lg {
    padding: 16px 32px;
    font-size: 18px;
}

.btn-block {
    width: 100%;
}

/* ============================================
   FORMS
   ============================================ */
.form-group {
    margin-bottom: var(--spacing-lg);
}

.form-label {
    display: block;
    margin-bottom: var(--spacing-sm);
    font-weight: 600;
    color: var(--color-gray-700);
    font-size: 14px;
}

.form-label.required::after {
    content: ' *';
    color: var(--color-error);
}

.form-input,
.form-select,
.form-textarea {
    width: 100%;
    padding: 12px 16px;
    font-family: var(--font-body);
    font-size: 16px;
    color: var(--color-gray-800);
    background: white;
    border: 2px solid var(--color-gray-300);
    border-radius: var(--radius-md);
    transition: all var(--transition-fast);
}

.form-input:focus,
.form-select:focus,
.form-textarea:focus {
    outline: none;
    border-color: var(--color-primary);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

.form-input.error,
.form-select.error,
.form-textarea.error {
    border-color: var(--color-error);
}

.form-input.success,
.form-select.success,
.form-textarea.success {
    border-color: var(--color-success);
}

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

.form-help {
    display: block;
    margin-top: var(--spacing-xs);
    font-size: 14px;
    color: var(--color-gray-500);
}

.form-error {
    display: block;
    margin-top: var(--spacing-xs);
    font-size: 14px;
    color: var(--color-error);
    font-weight: 500;
}

.form-success {
    display: block;
    margin-top: var(--spacing-xs);
    font-size: 14px;
    color: var(--color-success);
    font-weight: 500;
}

/* Checkbox & Radio */
.form-checkbox,
.form-radio {
    display: flex;
    align-items: flex-start;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-md);
}

.form-checkbox input[type="checkbox"],
.form-radio input[type="radio"] {
    margin-top: 4px;
    width: 18px;
    height: 18px;
    cursor: pointer;
}

.form-checkbox label,
.form-radio label {
    flex: 1;
    cursor: pointer;
    font-size: 14px;
    color: var(--color-gray-700);
}

/* ============================================
   CARDS
   ============================================ */
.card {
    background: white;
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-md);
    overflow: hidden;
}

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

.card-header {
    padding: var(--spacing-lg) var(--spacing-xl);
    border-bottom: 1px solid var(--color-gray-200);
}

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

/* ============================================
   ALERTS
   ============================================ */
.alert {
    padding: var(--spacing-md) var(--spacing-lg);
    border-radius: var(--radius-md);
    margin-bottom: var(--spacing-lg);
    border-left: 4px solid;
}

.alert-success {
    background: #D1FAE5;
    border-color: var(--color-success);
    color: #065F46;
}

.alert-error {
    background: #FEE2E2;
    border-color: var(--color-error);
    color: #991B1B;
}

.alert-warning {
    background: #FEF3C7;
    border-color: var(--color-warning);
    color: #92400E;
}

.alert-info {
    background: #DBEAFE;
    border-color: var(--color-info);
    color: #1E40AF;
}

/* ============================================
   BADGES
   ============================================ */
.badge {
    display: inline-flex;
    align-items: center;
    padding: 4px 12px;
    font-size: 12px;
    font-weight: 600;
    border-radius: var(--radius-full);
}

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

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

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

/* ============================================
   UTILITIES
   ============================================ */
.text-center { text-align: center; }
.text-left { text-align: left; }
.text-right { text-align: right; }

.text-primary { color: var(--color-primary); }
.text-orange { color: var(--color-orange); }
.text-green { color: var(--color-green); }
.text-gray { color: var(--color-gray-500); }
.text-muted { color: var(--color-gray-600); }

.bg-primary { background: var(--color-primary); }
.bg-orange { background: var(--color-orange); }
.bg-green { background: var(--color-green); }
.bg-yellow { background: var(--color-yellow); }
.bg-gray { background: var(--color-gray-100); }

.mt-0 { margin-top: 0; }
.mt-1 { margin-top: var(--spacing-sm); }
.mt-2 { margin-top: var(--spacing-md); }
.mt-3 { margin-top: var(--spacing-lg); }
.mt-4 { margin-top: var(--spacing-xl); }

.mb-0 { margin-bottom: 0; }
.mb-1 { margin-bottom: var(--spacing-sm); }
.mb-2 { margin-bottom: var(--spacing-md); }
.mb-3 { margin-bottom: var(--spacing-lg); }
.mb-4 { margin-bottom: var(--spacing-xl); }

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

.gap-1 { gap: var(--spacing-sm); }
.gap-2 { gap: var(--spacing-md); }
.gap-3 { gap: var(--spacing-lg); }

/* ============================================
   RESPONSIVE
   ============================================ */
@media (max-width: 768px) {
    h1 { font-size: 2rem; }
    h2 { font-size: 1.75rem; }
    h3 { font-size: 1.5rem; }
    
    .section {
        padding: var(--spacing-2xl) 0;
    }
    
    .container {
        padding: 0 var(--spacing-md);
    }
    
    .btn-lg {
        padding: 14px 24px;
        font-size: 16px;
    }
}

/* ============================================
   ANIMATIONS
   ============================================ */
@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

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

.fade-in {
    animation: fadeIn 0.6s ease forwards;
}

.slide-in {
    animation: slideInRight 0.6s ease forwards;
}

/* ============================================
   LOADING SPINNER
   ============================================ */
.spinner {
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 3px solid rgba(255, 255, 255, 0.3);
    border-top-color: white;
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
}

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

/* ============================================
   PRINT STYLES
   ============================================ */
@media print {
    .no-print {
        display: none !important;
    }
}