/* ============================================
   Email Validator Landing Page - Custom Styles
   ============================================ */

/* CSS Custom Properties */
:root {
    /* Primary Colors */
    --color-primary-50: #EEF2FF;
    --color-primary-100: #E0E7FF;
    --color-primary-200: #C7D2FE;
    --color-primary-500: #6366F1;
    --color-primary-600: #4F46E5;
    --color-primary-700: #4338CA;
    --color-primary-900: #312E81;
    
    /* Secondary Colors */
    --color-secondary-400: #A78BFA;
    --color-secondary-500: #8B5CF6;
    --color-secondary-600: #7C3AED;
    
    /* Neutral Colors */
    --color-gray-50: #F9FAFB;
    --color-gray-100: #F3F4F6;
    --color-gray-200: #E5E7EB;
    --color-gray-400: #9CA3AF;
    --color-gray-600: #4B5563;
    --color-gray-800: #1F2937;
    --color-gray-900: #111827;
    
    /* Semantic Colors */
    --color-success: #10B981;
    --color-warning: #F59E0B;
    --color-error: #EF4444;
    --color-info: #3B82F6;
    
    /* Gradients */
    --gradient-hero: linear-gradient(135deg, #312E81 0%, #4F46E5 50%, #7C3AED 100%);
    --gradient-button: linear-gradient(135deg, #4F46E5 0%, #7C3AED 100%);
    --gradient-card-hover: linear-gradient(180deg, rgba(99, 102, 241, 0.05) 0%, transparent 100%);
    
    /* Transitions */
    --transition-base: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-fast: all 0.15s ease-in-out;
    --transition-slow: all 0.5s cubic-bezier(0.4, 0, 0.2, 1);
}

/* ============================================
   Base Styles
   ============================================ */

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    color: var(--color-gray-900);
    background-color: var(--color-gray-50);
}

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

/* ============================================
   Accessibility - Skip Link
   ============================================ */

.skip-link {
    position: absolute;
    top: -100%;
    left: 0;
    background: var(--color-primary-600);
    color: white;
    padding: 12px 24px;
    z-index: 1000;
    text-decoration: none;
    font-weight: 600;
    border-radius: 0 0 8px 0;
    transition: top 0.3s;
}

.skip-link:focus {
    top: 0;
    outline: 2px solid white;
    outline-offset: 2px;
}

/* Focus Styles - WCAG 2.1 AA */
:focus-visible {
    outline: 3px solid var(--color-primary-500);
    outline-offset: 2px;
}

button:focus-visible,
a:focus-visible,
input:focus-visible {
    outline: 3px solid var(--color-primary-500);
    outline-offset: 2px;
}

/* Screen Reader Only */
.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;
}

/* ============================================
   Header & Navigation
   ============================================ */

#header {
    background: rgba(255, 255, 255, 0.9);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
}

#header.scrolled {
    background: rgba(255, 255, 255, 0.95);
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
}

/* ============================================
   Buttons
   ============================================ */

.btn-primary {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 12px 24px;
    background: var(--gradient-button);
    color: white;
    font-weight: 600;
    font-size: 16px;
    border-radius: 12px;
    text-decoration: none;
    transition: var(--transition-base);
    border: none;
    cursor: pointer;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 25px -5px rgba(79, 70, 229, 0.4);
}

.btn-primary:active {
    transform: scale(0.98);
}

.btn-primary.btn-large {
    padding: 16px 32px;
    font-size: 18px;
    border-radius: 14px;
}

.btn-secondary {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 12px 24px;
    background: white;
    color: var(--color-primary-600);
    font-weight: 600;
    font-size: 16px;
    border-radius: 12px;
    text-decoration: none;
    border: 2px solid var(--color-primary-600);
    transition: var(--transition-base);
    cursor: pointer;
}

.btn-secondary:hover {
    background: var(--color-primary-50);
    transform: translateY(-2px);
}

/* ============================================
   Hero Section
   ============================================ */

.hero-background {
    background: var(--gradient-hero);
    background-size: 200% 200%;
    animation: meshGradient 15s ease infinite;
}

@keyframes meshGradient {
    0%, 100% {
        background-position: 0% 50%;
    }
    50% {
        background-position: 100% 50%;
    }
}

.hero-pattern {
    background-image: 
        linear-gradient(rgba(255, 255, 255, 0.1) 1px, transparent 1px),
        linear-gradient(90deg, rgba(255, 255, 255, 0.1) 1px, transparent 1px);
    background-size: 40px 40px;
}

/* ============================================
   Section Padding
   ============================================ */

.section-padding {
    padding: 80px 0;
}

@media (max-width: 768px) {
    .section-padding {
        padding: 48px 0;
    }
}

/* ============================================
   Features Grid
   ============================================ */

.features-grid {
    display: grid;
    grid-template-columns: repeat(1, 1fr);
    gap: 24px;
}

@media (min-width: 640px) {
    .features-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (min-width: 1024px) {
    .features-grid {
        grid-template-columns: repeat(4, 1fr);
    }
}

.feature-card {
    background: white;
    border-radius: 16px;
    padding: 32px 24px;
    text-align: center;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
    transition: var(--transition-base);
    border: 1px solid var(--color-gray-200);
}

.feature-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
    border-color: var(--color-primary-200);
}

.feature-icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 72px;
    height: 72px;
    border-radius: 16px;
    background: linear-gradient(135deg, var(--color-primary-50) 0%, var(--color-primary-100) 100%);
    margin-bottom: 20px;
    color: var(--color-primary-600);
}

.feature-title {
    font-size: 20px;
    font-weight: 600;
    color: var(--color-gray-800);
    margin-bottom: 12px;
}

.feature-description {
    font-size: 14px;
    color: var(--color-gray-600);
    line-height: 1.6;
}

/* ============================================
   How It Works - Steps
   ============================================ */

.steps-grid {
    display: grid;
    grid-template-columns: repeat(1, 1fr);
    gap: 32px;
    list-style: none;
    padding: 0;
    margin: 0;
}

@media (min-width: 768px) {
    .steps-grid {
        grid-template-columns: repeat(4, 1fr);
    }
}

.step-card {
    text-align: center;
    position: relative;
}

.step-number {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    background: var(--gradient-button);
    color: white;
    font-weight: 700;
    font-size: 18px;
    border-radius: 50%;
    margin-bottom: 20px;
}

.step-icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 80px;
    height: 80px;
    border-radius: 20px;
    background: var(--color-gray-100);
    margin-bottom: 20px;
    color: var(--color-primary-600);
}

.step-title {
    font-size: 18px;
    font-weight: 600;
    color: var(--color-gray-800);
    margin-bottom: 8px;
}

.step-description {
    font-size: 14px;
    color: var(--color-gray-600);
    line-height: 1.5;
}

/* Connector line between steps */
@media (min-width: 768px) {
    .step-card:not(:last-child)::after {
        content: '';
        position: absolute;
        top: 20px;
        left: calc(50% + 40px);
        width: calc(100% - 80px);
        height: 2px;
        background: linear-gradient(90deg, var(--color-primary-300), var(--color-secondary-300));
        z-index: 0;
    }
}

/* ============================================
   Testimonials
   ============================================ */

.testimonial-card {
    background: white;
    border-radius: 16px;
    padding: 32px;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
    border: 1px solid var(--color-gray-200);
    transition: var(--transition-base);
}

.testimonial-card:hover {
    box-shadow: 0 10px 25px -5px rgba(0, 0, 0, 0.1);
}

.testimonial-quote {
    margin-bottom: 24px;
}

.testimonial-quote p {
    font-size: 16px;
    color: var(--color-gray-700);
    line-height: 1.6;
    font-style: italic;
}

.testimonial-author {
    display: flex;
    align-items: center;
    gap: 16px;
}

.avatar {
    width: 56px;
    height: 56px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    font-size: 18px;
    color: white;
    flex-shrink: 0;
}

.avatar-primary {
    background: linear-gradient(135deg, var(--color-primary-500), var(--color-primary-700));
}

.avatar-secondary {
    background: linear-gradient(135deg, var(--color-secondary-500), var(--color-secondary-600));
}

.avatar-accent {
    background: linear-gradient(135deg, var(--color-success), #059669);
}

.author-name {
    display: block;
    font-weight: 600;
    color: var(--color-gray-900);
    font-style: normal;
}

.author-title {
    font-size: 14px;
    color: var(--color-gray-600);
    margin-top: 2px;
}

.author-meta {
    font-size: 12px;
    color: var(--color-gray-400);
    margin-top: 2px;
}

/* Company Logos */
.company-logo {
    font-size: 16px;
    font-weight: 600;
    color: var(--color-gray-400);
    transition: var(--transition-base);
}

.company-logo:hover {
    color: var(--color-primary-600);
}

/* ============================================
   Pricing
   ============================================ */

.pricing-toggle-btn {
    padding: 10px 20px;
    border-radius: 9999px;
    font-weight: 500;
    font-size: 14px;
    color: var(--color-gray-600);
    background: transparent;
    border: none;
    cursor: pointer;
    transition: var(--transition-base);
}

.pricing-toggle-btn:hover {
    color: var(--color-gray-900);
}

.pricing-toggle-btn--active {
    background: white;
    color: var(--color-gray-900);
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

.pricing-card {
    background: white;
    border-radius: 20px;
    padding: 32px;
    text-align: center;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
    border: 2px solid var(--color-gray-200);
    transition: var(--transition-base);
    position: relative;
}

.pricing-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
}

.pricing-card--popular {
    border-color: var(--color-primary-500);
    transform: scale(1.05);
}

.pricing-card--popular:hover {
    transform: scale(1.05) translateY(-4px);
}

.badge-popular {
    position: absolute;
    top: -12px;
    left: 50%;
    transform: translateX(-50%);
    background: var(--gradient-button);
    color: white;
    font-size: 12px;
    font-weight: 600;
    padding: 4px 16px;
    border-radius: 9999px;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.pricing-plan-name {
    font-size: 24px;
    font-weight: 700;
    color: var(--color-gray-900);
    margin-bottom: 16px;
}

.pricing-price {
    margin-bottom: 8px;
}

.price-amount {
    font-size: 48px;
    font-weight: 700;
    color: var(--color-gray-900);
}

.price-currency {
    font-size: 18px;
    color: var(--color-gray-600);
}

.pricing-checks {
    font-size: 14px;
    color: var(--color-gray-500);
    margin-bottom: 24px;
}

.pricing-features {
    list-style: none;
    padding: 0;
    margin: 0 0 32px 0;
    text-align: left;
}

.pricing-features li {
    padding: 8px 0;
    font-size: 14px;
    color: var(--color-gray-700);
    display: flex;
    align-items: center;
    gap: 12px;
}

.pricing-features li::before {
    content: '✓';
    color: var(--color-success);
    font-weight: 700;
}

/* ============================================
   FAQ Accordion
   ============================================ */

.faq-item {
    border-bottom: 1px solid var(--color-gray-200);
}

.faq-question {
    width: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 24px 0;
    background: none;
    border: none;
    cursor: pointer;
    text-align: left;
    font-size: 18px;
    font-weight: 600;
    color: var(--color-gray-900);
    transition: var(--transition-base);
}

.faq-question:hover {
    color: var(--color-primary-600);
}

.faq-icon {
    width: 24px;
    height: 24px;
    flex-shrink: 0;
    transition: transform 0.3s ease;
}

.faq-question[aria-expanded="true"] .faq-icon {
    transform: rotate(180deg);
}

.faq-answer {
    padding-bottom: 24px;
    overflow: hidden;
    transition: max-height 0.3s ease-out, padding 0.3s ease-out;
    max-height: 0;
}

.faq-answer:not([hidden]) {
    max-height: 200px;
}

.faq-answer p {
    font-size: 16px;
    color: var(--color-gray-600);
    line-height: 1.6;
}

/* ============================================
   CTA Section
   ============================================ */

.cta-section {
    background: var(--gradient-button);
    position: relative;
    overflow: hidden;
}

.cta-section::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-image: 
        radial-gradient(circle at 20% 50%, rgba(255, 255, 255, 0.1) 0%, transparent 50%),
        radial-gradient(circle at 80% 50%, rgba(255, 255, 255, 0.1) 0%, transparent 50%);
}

.cta-content {
    position: relative;
    z-index: 1;
    text-align: center;
    max-width: 600px;
    margin: 0 auto;
}

.cta-form {
    max-width: 480px;
    margin: 0 auto;
}

.cta-form .form-group {
    display: flex;
    gap: 12px;
}

@media (max-width: 640px) {
    .cta-form .form-group {
        flex-direction: column;
    }
}

.cta-input {
    flex: 1;
    padding: 16px 20px;
    font-size: 16px;
    border: 2px solid rgba(255, 255, 255, 0.3);
    border-radius: 12px;
    background: rgba(255, 255, 255, 0.1);
    color: white;
    transition: var(--transition-base);
}

.cta-input::placeholder {
    color: rgba(255, 255, 255, 0.6);
}

.cta-input:focus {
    outline: none;
    border-color: white;
    background: rgba(255, 255, 255, 0.15);
}

.cta-input:invalid:not(:placeholder-shown) {
    border-color: var(--color-error);
}

.cta-button {
    display: inline-flex;
    align-items: center;
    padding: 16px 28px;
    background: white;
    color: var(--color-primary-600);
    font-weight: 600;
    font-size: 16px;
    border-radius: 12px;
    border: none;
    cursor: pointer;
    transition: var(--transition-base);
    white-space: nowrap;
}

.cta-button:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 25px -5px rgba(0, 0, 0, 0.2);
}

.cta-form .error-message {
    color: #FECACA;
    font-size: 14px;
    margin-top: 8px;
    text-align: left;
}

/* ============================================
   Footer
   ============================================ */

footer a {
    transition: color 0.2s ease;
}

footer a:hover {
    color: white !important;
}

/* ============================================
   Scroll Animations
   ============================================ */

.animate-on-scroll {
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.6s ease-out, transform 0.6s ease-out;
}

.animate-on-scroll.visible {
    opacity: 1;
    transform: translateY(0);
}

/* Stagger delays handled inline in HTML */

/* ============================================
   Mobile Menu
   ============================================ */

#mobile-menu {
    transition: max-height 0.3s ease-out, opacity 0.3s ease-out;
    max-height: 0;
    opacity: 0;
    overflow: hidden;
}

#mobile-menu.open {
    max-height: 400px;
    opacity: 1;
}

/* ============================================
   Utility Classes
   ============================================ */

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

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

.bg-primary-500 {
    background-color: var(--color-primary-500);
}

/* Container */
.container {
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 24px;
}

@media (max-width: 640px) {
    .container {
        padding: 0 16px;
    }
}

/* Grid */
.grid {
    display: grid;
    gap: 24px;
}

@media (min-width: 768px) {
    .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);
    }
}

/* ============================================
   Print Styles
   ============================================ */

@media print {
    .skip-link,
    #header,
    .cta-section,
    .animate-on-scroll {
        display: none !important;
    }
    
    body {
        background: white;
        color: black;
    }
    
    .section-padding {
        padding: 40px 0;
    }
}