:root {
    --primary-color: #2563eb;
    --secondary-color: #1e40af;
    --text-color: #1f2937;
    --light-text: #6b7280;
    --background: #ffffff;
    --light-background: #f3f4f6;
    --border-color: #e5e7eb;
    --card-background: white;
}

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

body {
    font-family: 'Inter', sans-serif;
    color: var(--text-color);
    line-height: 1.5;
}

/* Navigation */
nav {
    position: fixed;
    width: 100%;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border-color);
    z-index: 1000;
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 1rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.5rem;
    font-weight: bold;
    text-decoration: none;
    background: linear-gradient(to right, var(--text-color), var(--primary-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

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

.nav-links {
    display: flex;
    gap: 2rem;
    align-items: center;
}

.nav-links a {
    text-decoration: none;
    color: var(--text-color);
    font-weight: 500;
    transition: color 0.3s ease;
}

.nav-links a:hover {
    color: var(--primary-color);
}

/* Hero Section */
.hero {
    position: relative;
    min-height: 80vh;
    display: flex;
    align-items: center;
    padding: 4rem 2rem;
    background: linear-gradient(to bottom right, #f0f9ff, #ffffff);
    overflow: hidden;
}

.hero-content {
    max-width: 1200px;
    margin: 0 auto;
    z-index: 1;
}

.hero h1 {
    font-size: 3.5rem;
    font-weight: 700;
    line-height: 1.2;
    margin-bottom: 1.5rem;
    background: linear-gradient(to right, var(--text-color), var(--primary-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.subtitle {
    font-size: 1.25rem;
    color: var(--light-text);
    margin-bottom: 2rem;
    max-width: 600px;
}

.gradient-sphere {
    position: absolute;
    width: 600px;
    height: 600px;
    right: -100px;
    top: 50%;
    transform: translateY(-50%);
    background: radial-gradient(circle, rgba(37,99,235,0.1) 0%, rgba(37,99,235,0) 70%);
    border-radius: 50%;
    animation: float 6s ease-in-out infinite;
}

/* Buttons */
.cta-group {
    display: flex;
    gap: 1rem;
}

.primary-button {
    display: inline-block;
    padding: 1rem 2rem;
    background: linear-gradient(to right, var(--text-color), var(--primary-color));
    color: white;
    border: none;
    border-radius: 0.5rem;
    font-size: 1rem;
    font-weight: 600;
    text-decoration: none;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    cursor: pointer;
}

.primary-button:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
}

.contact-form button.primary-button {
    width: 100%;
    margin-top: 1rem;
}

.secondary-button {
    background: white;
    color: var(--primary-color);
    border: 1px solid var(--primary-color);
    padding: 0.75rem 1.5rem;
    border-radius: 0.5rem;
    font-weight: 500;
    text-decoration: none;
    transition: all 0.3s ease;
}

.secondary-button:hover {
    background: var(--light-background);
}

/* Styles communs pour les titres de section */
section h2 {
    font-size: 2.5rem;
    text-align: center;
    margin-bottom: 1rem;
    background: linear-gradient(135deg, #1a1a1a 0%, var(--primary-color) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    font-weight: 600;
}

section .subtitle,
.features .subtitle,
.methodology .subtitle,
.contact .subtitle {
    font-size: 1.25rem;
    color: var(--light-text);
    margin: 0 auto 2rem;
    max-width: 600px;
    text-align: center;
}

/* Features Section */
.features {
    padding: 4rem 2rem;
    background-color: var(--background);
}

.features-content {
    max-width: 1200px;
    margin: 0 auto;
    text-align: center;
}

.features h2 {
    font-size: 2.5rem;
    text-align: center;
    margin-bottom: 0.5rem;
    background: linear-gradient(135deg, #1a1a1a 0%, var(--primary-color) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    font-weight: 600;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    max-width: 1200px;
    margin: 0 auto;
}

.feature-card {
    padding: 2rem;
    background: white;
    border-radius: 1rem;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s ease;
}

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

.feature-icon {
    font-size: 2rem;
    margin-bottom: 1rem;
}

.feature-card h3, .methodology-card h3 {
    font-size: 1.25rem;
    margin-bottom: 0.75rem;
    color: var(--text-color);
    font-weight: 600;
}

.feature-card p, .methodology-card p {
    color: var(--light-text);
    line-height: 1.5;
    font-size: 0.95rem;
    margin: 0;
    opacity: 0.8;
}

/* How it Works Section */
.how-it-works {
    padding: 3rem 2rem;
    background: var(--light-background);
}

/* Methodology Section */
.methodology {
    padding: 3rem 2rem;
    background: var(--background);
}

.methodology h2 {
    text-align: center;
    font-size: 3rem;
    margin-bottom: 0.5rem;
    background: linear-gradient(to right, var(--text-color), var(--primary-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.methodology .subtitle {
    margin-top: 0;
    margin-bottom: 3rem;
}

.methodology-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 2rem;
    max-width: 1200px;
    margin: 0 auto;
}

.methodology-card {
    background: var(--card-background);
    padding: 2rem;
    border-radius: 1rem;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s ease;
    text-align: center;
}

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

.methodology-icon {
    font-size: 2.5rem;
    margin-bottom: 1.5rem;
    color: var(--primary-color);
}

/* Contact Section */
.contact {
    padding: 3rem 2rem;
    background: white;
}

.contact-content {
    max-width: 1200px;
    margin: 0 auto;
    text-align: center;
}

.contact h2 {
    text-align: center;
    font-size: 3rem;
    margin-bottom: 1rem;
    background: linear-gradient(to right, var(--text-color), var(--primary-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.contact p {
    font-size: 1.25rem;
    color: var(--light-text);
    margin-bottom: 2rem;
    line-height: 1.6;
    max-width: 800px;
    margin-left: auto;
    margin-right: auto;
}

.contact-form {
    max-width: 33%;
    margin: 0 auto;
}

.form-group {
    margin-bottom: 1.5rem;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 0.75rem;
    border: 1px solid var(--border-color);
    border-radius: 0.5rem;
    font-size: 1rem;
    transition: border-color 0.3s ease;
}

/* Responsive adjustments */
@media (max-width: 768px) {
    .contact-form {
        max-width: 100%;
        padding: 0 1rem;
    }
}

/* Section de démonstration */
.features-demo {
    padding: 4rem 2rem;
    background: linear-gradient(135deg, var(--dark-background) 0%, var(--primary-color-dark) 100%);
    color: white;
}

.features-content-demo {
    max-width: 1200px;
    margin: 0 auto;
    text-align: center;
}

.features-demo h2 {
    font-size: 2.5rem;
    margin-bottom: 1rem;
    background: linear-gradient(135deg, #ffffff 0%, #e0e0e0 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.features-demo p {
    font-size: 1.2rem;
    margin-bottom: 3rem;
    opacity: 0.9;
}

.demo-interface {
    position: relative;
    width: 100%;
    max-width: 1200px;
    margin: 2rem auto;
    padding: 2rem;
}

.interface-stack {
    position: relative;
    width: 100%;
    max-width: 1200px;
    height: 600px;
    margin: 0 auto;
    perspective: 2000px;
}

.interface-image {
    position: absolute;
    width: 80%;
    max-width: 800px;
    height: auto;
    border-radius: 8px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
    transition: all 0.8s ease;
    transform-style: preserve-3d;
    opacity: 1;
}

.interface-image:nth-child(1) {
    left: 50%;
    transform: translateX(-50%) translateY(50px);
    z-index: 3;
    transition-delay: 0.2s;
}

.interface-image:nth-child(2) {
    left: 40%;
    transform: translateX(-50%) translateY(170px);
    z-index: 2;
    transition-delay: 0.4s;
}

.interface-image:nth-child(3) {
    left: 60%;
    transform: translateX(-50%) translateY(230px);
    z-index: 1;
    transition-delay: 0.6s;
}

.interface-stack.animate .interface-image:nth-child(1) {
    transform: translateX(-50%) translateY(-20px) rotateX(10deg);
}

.interface-stack.animate .interface-image:nth-child(2) {
    transform: translateX(-80%) translateY(100px) rotateX(10deg) rotateY(-15deg);
}

.interface-stack.animate .interface-image:nth-child(3) {
    transform: translateX(-20%) translateY(160px) rotateX(10deg) rotateY(15deg);
}

/* Footer */
footer {
    background: var(--light-background);
    padding: 4rem 2rem 2rem;
}

.footer-content {
    max-width: 1200px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 2rem;
}

.footer-section h4 {
    margin-bottom: 1rem;
}

.footer-section a {
    display: block;
    color: var(--light-text);
    text-decoration: none;
    margin-bottom: 0.5rem;
}

.footer-bottom {
    text-align: center;
    margin-top: 3rem;
    padding-top: 2rem;
    border-top: 1px solid var(--border-color);
}

/* Animations */
@keyframes float {
    0% {
        transform: translateY(-50%) translateX(0);
    }
    50% {
        transform: translateY(-50%) translateX(20px);
    }
    100% {
        transform: translateY(-50%) translateX(0);
    }
}

/* Responsive Design */
@media (max-width: 1024px) {
    .methodology-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 768px) {
    .nav-links {
        display: none;
    }
    
    .hero h1 {
        font-size: 2.5rem;
    }
    
    .gradient-sphere {
        width: 300px;
        height: 300px;
        right: -150px;
    }
    
    .features-demo h2 {
        font-size: 2rem;
    }
    
    .features-demo p {
        font-size: 1rem;
    }
    
    .demo-interface {
        transform: none;
        margin: 1rem auto;
    }
}

@media (max-width: 640px) {
    .hero {
        padding: 4rem 1rem 2rem;
    }
    
    .features,
    .how-it-works,
    .contact {
        padding: 4rem 1rem;
    }
}