/* ========================================
   Reset & Base Styles
   ======================================== */

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

:root {
    /* Colors */
    --primary-color: #0066cc;
    --primary-dark: #0052a3;
    --secondary-color: #6ba3d8;
    --text-dark: #1a1a1a;
    --text-light: #ffffff;
    --text-gray: #666666;
    --bg-light: #f5f7fa;
    --bg-dark: #2a2a2a;
    --bg-white: #ffffff;
    --border-color: #e0e0e0;
    
    /* Typography */
    --font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    --font-size-base: 16px;
    --line-height-base: 1.6;
    
    /* Spacing */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 2rem;
    --spacing-lg: 3rem;
    --spacing-xl: 4rem;
    --spacing-xxl: 6rem;
    
    /* Container */
    --container-max-width: 1200px;
    
    /* Transitions */
    --transition-speed: 0.3s;
}

body {
    font-family: var(--font-family);
    font-size: var(--font-size-base);
    line-height: var(--line-height-base);
    color: var(--text-dark);
    background-color: var(--bg-white);
}

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

a {
    text-decoration: none;
    color: inherit;
    transition: color var(--transition-speed);
}

button {
    font-family: inherit;
    cursor: pointer;
    border: none;
    transition: all var(--transition-speed);
}

/* ========================================
   Container
   ======================================== */

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

/* ========================================
   Typography
   ======================================== */

.section-title {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: var(--spacing-md);
    color: var(--text-dark);
    line-height: 1.2;
}

.section-description {
    font-size: 1.125rem;
    color: var(--text-gray);
    line-height: 1.7;
    max-width: 800px;
}

.section-header {
    text-align: center;
    margin-bottom: var(--spacing-xl);
}

.section-header .section-description {
    margin: 0 auto;
}

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

.btn {
    display: inline-block;
    padding: 1rem 2.5rem;
    font-size: 1rem;
    font-weight: 600;
    border-radius: 8px;
    transition: all var(--transition-speed);
}

.btn-primary {
    background-color: var(--secondary-color);
    color: var(--text-light);
}

.btn-primary:hover {
    background-color: var(--primary-color);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0, 102, 204, 0.3);
}

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

.btn-secondary:hover {
    background-color: var(--primary-color);
    color: var(--text-light);
}

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

.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background-color: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    z-index: 1000;
    padding: var(--spacing-sm) 0;
}

.nav-container {
    max-width: var(--container-max-width);
    margin: 0 auto;
    padding: 0 var(--spacing-md);
    display: flex;
    justify-content: flex-end;
    align-items: center;
}

.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 4px;
    background: none;
    padding: 0.5rem;
}

.nav-toggle span {
    display: block;
    width: 25px;
    height: 3px;
    background-color: var(--text-dark);
    transition: all var(--transition-speed);
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: var(--spacing-lg);
}

.nav-menu a {
    font-weight: 500;
    color: var(--text-dark);
    position: relative;
}

.nav-menu a::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background-color: var(--primary-color);
    transition: width var(--transition-speed);
}

.nav-menu a:hover::after {
    width: 100%;
}

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

.hero {
    position: relative;
    height: 100vh;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    background-image: 
        linear-gradient(135deg, rgba(102, 126, 234, 0.8) 0%, rgba(118, 75, 162, 0.8) 100%),
        url('https://images.unsplash.com/photo-1557821552-17105176677c?w=1920&h=1080&fit=crop');
    background-size: cover;
    background-position: center;
    background-attachment: fixed;
    color: var(--text-light);
}

.hero-content {
    padding: var(--spacing-md);
    animation: fadeInUp 1s ease-out;
}

.hero-title {
    font-size: 4rem;
    font-weight: 700;
    margin-bottom: var(--spacing-sm);
    letter-spacing: -1px;
}

.hero-subtitle {
    font-size: 1.5rem;
    font-weight: 400;
    margin-bottom: var(--spacing-xs);
    opacity: 0.95;
}

.hero-tagline {
    font-size: 1.25rem;
    font-weight: 300;
    opacity: 0.9;
}

.scroll-indicator {
    position: absolute;
    bottom: var(--spacing-lg);
    left: 50%;
    transform: translateX(-50%);
    animation: bounce 2s infinite;
}

.scroll-icon {
    color: var(--text-light);
    opacity: 0.8;
}

/* ========================================
   Introduction Section
   ======================================== */

.intro-section {
    padding: var(--spacing-xxl) 0;
    background-color: var(--bg-light);
}

.intro-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-xl);
    align-items: center;
}

.intro-text .section-title {
    color: var(--primary-color);
    text-align: left;
}

.intro-text .section-description {
    margin-bottom: var(--spacing-md);
}

.intro-image {
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.1);
}

.intro-image img {
    width: 100%;
    height: auto;
    transition: transform var(--transition-speed);
}

.intro-image:hover img {
    transform: scale(1.05);
}

/* ========================================
   Problem Section
   ======================================== */

.problem-section {
    padding: var(--spacing-xxl) 0;
    background-color: var(--bg-white);
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--spacing-lg);
}

.feature-card {
    background-color: var(--bg-light);
    padding: var(--spacing-lg);
    border-radius: 12px;
    text-align: center;
    transition: all var(--transition-speed);
}

.feature-card:hover {
    transform: translateY(-8px);
    box-shadow: 0 12px 30px rgba(0, 0, 0, 0.1);
}

.feature-icon {
    width: 80px;
    height: 80px;
    margin: 0 auto var(--spacing-md);
    display: flex;
    align-items: center;
    justify-content: center;
    background-color: var(--bg-white);
    border-radius: 50%;
}

.feature-icon svg {
    color: var(--primary-color);
}

.feature-title {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: var(--spacing-sm);
    color: var(--primary-color);
}

.feature-description {
    font-size: 1rem;
    color: var(--text-gray);
    line-height: 1.6;
}

/* ========================================
   How It Works Section
   ======================================== */

.how-it-works-section {
    padding: var(--spacing-xxl) 0;
    background-color: var(--bg-dark);
    color: var(--text-light);
}

.how-it-works-section .section-title,
.how-it-works-section .section-description {
    color: var(--text-light);
}

.numbered-features {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--spacing-lg);
}

.numbered-feature {
    background-color: rgba(255, 255, 255, 0.05);
    padding: var(--spacing-lg);
    border-radius: 12px;
    transition: all var(--transition-speed);
}

.numbered-feature:hover {
    background-color: rgba(255, 255, 255, 0.1);
    transform: translateY(-4px);
}

.feature-number {
    width: 50px;
    height: 50px;
    display: flex;
    align-items: center;
    justify-content: center;
    background-color: transparent;
    border: 2px solid var(--secondary-color);
    border-radius: 50%;
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--secondary-color);
    margin-bottom: var(--spacing-md);
}

.numbered-feature .feature-title {
    color: var(--text-light);
    margin-bottom: var(--spacing-sm);
}

.numbered-feature .feature-description {
    color: rgba(255, 255, 255, 0.8);
}

/* ========================================
   Why Section
   ======================================== */

.why-section {
    padding: var(--spacing-xxl) 0;
    background-color: var(--bg-light);
}

.list-features {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-lg);
    max-width: 900px;
    margin: 0 auto;
}

.list-feature {
    background-color: var(--bg-white);
    padding: var(--spacing-lg);
    border-radius: 12px;
    border-left: 4px solid var(--primary-color);
    transition: all var(--transition-speed);
}

.list-feature:hover {
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.1);
    transform: translateX(8px);
}

.list-feature .feature-title {
    font-size: 1.5rem;
    margin-bottom: var(--spacing-sm);
}

/* ========================================
   Audience Section
   ======================================== */

.audience-section {
    padding: var(--spacing-xxl) 0;
    background-color: var(--bg-white);
}

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

.cta-section {
    padding: var(--spacing-xxl) 0;
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--primary-dark) 100%);
    color: var(--text-light);
    text-align: center;
}

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

.cta-section .section-title,
.cta-section .section-description {
    color: var(--text-light);
}

.cta-section .section-description {
    margin: 0 auto var(--spacing-lg);
}

.cta-section .btn-primary {
    background-color: var(--text-light);
    color: var(--primary-color);
}

.cta-section .btn-primary:hover {
    background-color: var(--bg-light);
    transform: translateY(-2px);
    box-shadow: 0 8px 20px rgba(0, 0, 0, 0.2);
}

/* ========================================
   Contact Section
   ======================================== */

.contact-section {
    padding: var(--spacing-xxl) 0;
    background-color: var(--bg-light);
}

.contact-info {
    display: flex;
    justify-content: center;
    gap: var(--spacing-xl);
    margin-bottom: var(--spacing-lg);
    flex-wrap: wrap;
}

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

.contact-label {
    font-size: 0.875rem;
    color: var(--text-gray);
    margin-bottom: var(--spacing-xs);
    text-transform: uppercase;
    letter-spacing: 1px;
}

.contact-link {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--primary-color);
}

.contact-link:hover {
    color: var(--primary-dark);
}

.contact-section .btn-secondary {
    display: block;
    margin: 0 auto;
}

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

.footer {
    padding: var(--spacing-lg) 0;
    background-color: var(--bg-dark);
    color: var(--text-light);
    text-align: center;
}

.footer-text {
    font-size: 0.875rem;
    opacity: 0.8;
}

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

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes bounce {
    0%, 20%, 50%, 80%, 100% {
        transform: translateX(-50%) translateY(0);
    }
    40% {
        transform: translateX(-50%) translateY(-10px);
    }
    60% {
        transform: translateX(-50%) translateY(-5px);
    }
}

/* ========================================
   Responsive Design
   ======================================== */

@media (max-width: 992px) {
    .section-title {
        font-size: 2rem;
    }
    
    .hero-title {
        font-size: 3rem;
    }
    
    .intro-grid {
        grid-template-columns: 1fr;
        gap: var(--spacing-lg);
    }
    
    .intro-text .section-title {
        text-align: center;
    }
    
    .features-grid {
        grid-template-columns: 1fr;
    }
    
    .numbered-features {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 768px) {
    :root {
        --spacing-xxl: 3rem;
        --spacing-xl: 2rem;
    }
    
    .header {
        padding: var(--spacing-xs) 0;
    }
    
    .nav-toggle {
        display: flex;
    }
    
    .nav-menu {
        position: fixed;
        top: 60px;
        right: -100%;
        width: 250px;
        height: calc(100vh - 60px);
        background-color: var(--bg-white);
        flex-direction: column;
        padding: var(--spacing-md);
        box-shadow: -2px 0 10px rgba(0, 0, 0, 0.1);
        transition: right var(--transition-speed);
    }
    
    .nav-menu.active {
        right: 0;
    }
    
    .hero-title {
        font-size: 2.5rem;
    }
    
    .hero-subtitle {
        font-size: 1.25rem;
    }
    
    .hero-tagline {
        font-size: 1rem;
    }
    
    .section-title {
        font-size: 1.75rem;
    }
    
    .section-description {
        font-size: 1rem;
    }
    
    .contact-info {
        flex-direction: column;
        gap: var(--spacing-md);
    }
}

@media (max-width: 480px) {
    .hero-title {
        font-size: 2rem;
    }
    
    .btn {
        padding: 0.875rem 2rem;
        font-size: 0.9375rem;
    }
}

/* ========================================
   Smooth Scrolling
   ======================================== */

html {
    scroll-behavior: smooth;
}

/* Offset for fixed header */
section {
    scroll-margin-top: 80px;
}

/* Modal Styles */
.modal-overlay {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.7);
    z-index: 1000;
    align-items: center;
    justify-content: center;
    padding: 20px;
}

.modal-overlay.active {
    display: flex;
    animation: fadeIn 0.3s ease;
}

.modal-container {
    background: white;
    border-radius: 12px;
    width: 100%;
    max-width: 500px;
    max-height: 90vh;
    overflow-y: auto;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
    animation: slideUp 0.3s ease;
}

.modal-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 24px;
    border-bottom: 1px solid #eaeaea;
}

.modal-title {
    margin: 0;
    font-size: 1.5rem;
    font-weight: 600;
    color: #333;
}

.modal-close {
    background: none;
    border: none;
    font-size: 28px;
    cursor: pointer;
    color: #666;
    line-height: 1;
    padding: 0;
    width: 32px;
    height: 32px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    transition: all 0.2s;
}

.modal-close:hover {
    background-color: #f5f5f5;
    color: #333;
}

.modal-body {
    padding: 24px;
}

/* Form Styles */
.form-group {
    margin-bottom: 24px;
}

.form-label {
    display: block;
    margin-bottom: 8px;
    font-weight: 500;
    color: #333;
}

.form-label.required::after {
    content: " *";
    color: #ff4757;
}

.form-input,
.form-textarea {
    width: 100%;
    padding: 12px 16px;
    border: 1px solid #ddd;
    border-radius: 8px;
    font-size: 16px;
    transition: all 0.2s;
    box-sizing: border-box;
}

.form-input:focus,
.form-textarea:focus {
    outline: none;
    border-color: #4d8aff;
    box-shadow: 0 0 0 3px rgba(77, 138, 255, 0.1);
}

.form-input.error,
.form-textarea.error {
    border-color: #ff4757;
}

.form-input::placeholder,
.form-textarea::placeholder {
    color: #999;
}

.form-hint {
    font-size: 14px;
    color: #666;
    margin-top: 6px;
}

/* Radio Group */
.radio-group {
    display: flex;
    flex-direction: column;
    gap: 12px;
    margin-top: 8px;
}

.radio-label {
    display: flex;
    align-items: center;
    cursor: pointer;
    padding: 12px 16px;
    border: 1px solid #ddd;
    border-radius: 8px;
    transition: all 0.2s;
}

.radio-label:hover {
    background-color: #f8f9fa;
    border-color: #4d8aff;
}

.radio-label input[type="radio"] {
    display: none;
}

.radio-custom {
    width: 20px;
    height: 20px;
    border: 2px solid #ddd;
    border-radius: 50%;
    margin-right: 12px;
    position: relative;
    transition: all 0.2s;
}

.radio-label input[type="radio"]:checked + .radio-custom {
    border-color: #4d8aff;
    background-color: #4d8aff;
}

.radio-label input[type="radio"]:checked + .radio-custom::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 8px;
    height: 8px;
    background: white;
    border-radius: 50%;
}

.radio-text {
    font-size: 16px;
    color: #333;
}

/* Form Footer */
.form-footer {
    margin-top: 32px;
    text-align: center;
}

.btn-submit {
    position: relative;
    min-width: 140px;
    padding: 14px 32px;
    font-size: 16px;
}

.btn-submit:disabled {
    opacity: 0.7;
    cursor: not-allowed;
}

.btn-text {
    transition: opacity 0.2s;
}

.btn-loader {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
}

.spinner {
    width: 20px;
    height: 20px;
    border: 2px solid rgba(255, 255, 255, 0.3);
    border-radius: 50%;
    border-top-color: white;
    animation: spin 1s ease-in-out infinite;
}

.form-message {
    margin-top: 16px;
    padding: 12px;
    border-radius: 8px;
    font-size: 14px;
    display: none;
}

.form-message.success {
    display: block;
    background-color: #d4edda;
    color: #155724;
    border: 1px solid #c3e6cb;
}

.form-message.error {
    display: block;
    background-color: #f8d7da;
    color: #721c24;
    border: 1px solid #f5c6cb;
}

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

@keyframes slideUp {
    from { 
        opacity: 0;
        transform: translateY(30px);
    }
    to { 
        opacity: 1;
        transform: translateY(0);
    }
}

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

/* Responsive */
@media (max-width: 576px) {
    .modal-container {
        margin: 0;
        border-radius: 0;
        max-height: 100vh;
        height: 100vh;
    }
    
    .modal-header {
        padding: 20px;
    }
    
    .modal-body {
        padding: 20px;
    }
    
    .radio-label {
        padding: 10px 14px;
    }
}