/*
 * TRAGUER AI - Stylesheet
 * Charte strictement Noir & Blanc
 * Design system selon CDC v1.0
 */

/* ========================================
   VARIABLES CSS - PALETTE NOIR & BLANC
   ======================================== */
:root {
    /* Couleurs strictement noir & blanc */
    --noir-pur: #000000;
    --blanc-pur: #FFFFFF;
    --gris-fonce: #222222;
    --gris-moyen: #555555;
    --gris-clair: #EEEEEE;
    --gris-tres-clair: #F5F5F5;

    /* Typographie */
    --font-primary: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --font-secondary: 'Playfair Display', Georgia, serif;

    /* Tailles de police */
    --text-base: 16px;
    --text-lg: 18px;
    --text-xl: 20px;
    --text-2xl: 24px;
    --text-3xl: 28px;
    --text-4xl: 32px;
    --text-5xl: 40px;
    --text-6xl: 48px;
    --text-7xl: 64px;

    /* Espacements */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 1.5rem;
    --spacing-lg: 2rem;
    --spacing-xl: 3rem;
    --spacing-2xl: 4rem;
    --spacing-3xl: 6rem;

    /* Breakpoints */
    --mobile-sm: 320px;
    --mobile: 480px;
    --tablet: 768px;
    --desktop-sm: 1024px;
    --desktop: 1280px;

    /* Transitions */
    --transition-fast: 0.2s ease;
    --transition-normal: 0.3s ease;
    --transition-slow: 0.5s ease;

    /* Ombres (en nuances de gris) */
    --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);
}

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

html {
    font-size: 16px;
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-primary);
    font-size: var(--text-base);
    line-height: 1.6;
    color: var(--noir-pur);
    background-color: var(--blanc-pur);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* ========================================
   TYPOGRAPHIE
   ======================================== */
h1, h2, h3, h4, h5, h6 {
    font-weight: 700;
    line-height: 1.2;
    margin-bottom: var(--spacing-md);
    color: var(--noir-pur);
}

h1 {
    font-size: var(--text-7xl);
    font-family: var(--font-secondary);
    font-weight: 900;
}

h2 {
    font-size: var(--text-5xl);
    font-weight: 800;
}

h3 {
    font-size: var(--text-3xl);
    font-weight: 700;
}

h4 {
    font-size: var(--text-2xl);
    font-weight: 600;
}

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

a {
    color: var(--noir-pur);
    text-decoration: none;
    transition: all var(--transition-fast);
}

a:hover {
    opacity: 0.7;
}

strong {
    font-weight: 700;
}

/* ========================================
   LAYOUT UTILITIES
   ======================================== */
.container {
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

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

.section-dark {
    background-color: var(--noir-pur);
    color: var(--blanc-pur);
}

.section-light {
    background-color: var(--blanc-pur);
    color: var(--noir-pur);
}

.section-gray {
    background-color: var(--gris-tres-clair);
}

/* ========================================
   HEADER & NAVIGATION
   ======================================== */
.main-header {
    background-color: var(--blanc-pur);
    border-bottom: 1px solid var(--gris-clair);
    position: sticky;
    top: 0;
    z-index: 1000;
    transition: box-shadow var(--transition-normal);
}

.main-header.scrolled {
    box-shadow: var(--shadow-md);
}

.navbar {
    padding: var(--spacing-sm) 0;
}

.nav-wrapper {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.nav-brand .logo {
    height: 40px;
    width: auto;
    display: block;
}

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

.nav-link {
    font-weight: 500;
    font-size: var(--text-base);
    padding: var(--spacing-xs) var(--spacing-sm);
    border-bottom: 2px solid transparent;
    transition: all var(--transition-fast);
    white-space: nowrap;
}

.nav-link:hover,
.nav-link.active {
    border-bottom-color: var(--noir-pur);
}

.nav-cta .btn {
    margin-left: var(--spacing-sm);
    white-space: nowrap;
}

/* Language Selector */
.lang-selector {
    position: relative;
}

.lang-toggle {
    background: none;
    border: 1px solid var(--gris-moyen);
    padding: var(--spacing-xs) var(--spacing-sm);
    cursor: pointer;
    font-family: var(--font-primary);
    font-size: 14px;
    font-weight: 600;
    transition: all var(--transition-fast);
}

.lang-toggle:hover {
    background-color: var(--gris-tres-clair);
}

.lang-menu {
    position: absolute;
    top: 100%;
    right: 0;
    background-color: var(--blanc-pur);
    border: 1px solid var(--gris-clair);
    box-shadow: var(--shadow-lg);
    list-style: none;
    margin-top: 4px;
    min-width: 150px;
    display: none;
    z-index: 2000;
}

.lang-menu.active {
    display: block;
}

.lang-menu li {
    border-bottom: 1px solid var(--gris-clair);
}

.lang-menu li:last-child {
    border-bottom: none;
}

.lang-link {
    display: block;
    padding: var(--spacing-sm);
    color: var(--noir-pur);
    transition: all var(--transition-fast);
}

.lang-link:hover,
.lang-link.active {
    background-color: var(--gris-tres-clair);
    opacity: 1;
}

/* Language selector in navigation */
.nav-item-lang {
    position: relative;
}

.nav-item-lang .lang-selector {
    position: relative;
}

.nav-item-lang .lang-toggle {
    background: none;
    border: 1px solid var(--gris-moyen);
    padding: 8px 12px;
    cursor: pointer;
    font-family: var(--font-primary);
    font-size: 14px;
    font-weight: 600;
    transition: all var(--transition-fast);
    border-radius: 4px;
}

.nav-item-lang .lang-toggle:hover {
    border-color: var(--noir-pur);
    background-color: var(--gris-tres-clair);
}

/* Desktop: position lang menu absolutely */
@media (min-width: 769px) {
    .nav-item-lang .lang-menu {
        position: absolute;
        top: 100%;
        right: 0;
        margin-top: 8px;
        left: auto;
    }

    .nav-item-lang .lang-menu.active {
        display: block !important;
    }
}

/* Mobile: show lang selector inline */
@media (max-width: 768px) {
    .nav-item-lang {
        width: 100%;
        text-align: center;
        padding: var(--spacing-sm) 0;
    }

    .nav-item-lang .lang-toggle {
        width: 80%;
        max-width: 200px;
    }

    .nav-item-lang .lang-menu {
        position: static;
        width: 80%;
        max-width: 200px;
        margin: 8px auto 0;
    }

    .nav-item-lang .lang-menu.active {
        display: block !important;
    }
}

/* Hamburger Menu (Mobile) */
.nav-toggle {
    display: none;
    flex-direction: column;
    background: none;
    border: none;
    cursor: pointer;
    padding: var(--spacing-xs);
}

.hamburger {
    width: 25px;
    height: 2px;
    background-color: var(--noir-pur);
    margin: 3px 0;
    transition: all var(--transition-fast);
}

/* ========================================
   BUTTONS
   ======================================== */
.btn {
    display: inline-block;
    padding: var(--spacing-sm) var(--spacing-lg);
    font-size: var(--text-base);
    font-weight: 600;
    text-align: center;
    cursor: pointer;
    border: 2px solid var(--noir-pur);
    background-color: var(--noir-pur);
    color: var(--blanc-pur);
    transition: all var(--transition-normal);
    text-decoration: none;
}

.btn:hover {
    background-color: var(--blanc-pur);
    color: var(--noir-pur);
    opacity: 1;
}

.btn-primary {
    background-color: var(--noir-pur);
    color: var(--blanc-pur);
    border-color: var(--noir-pur);
}

.btn-secondary {
    background-color: var(--blanc-pur);
    color: var(--noir-pur);
    border-color: var(--noir-pur);
}

.btn-secondary:hover {
    background-color: var(--noir-pur);
    color: var(--blanc-pur);
}

.btn-large {
    padding: var(--spacing-md) var(--spacing-xl);
    font-size: var(--text-lg);
}

/* ========================================
   CARDS & COMPONENTS
   ======================================== */
.card {
    background-color: var(--blanc-pur);
    border: 1px solid var(--gris-clair);
    padding: var(--spacing-lg);
    transition: all var(--transition-normal);
}

.card:hover {
    box-shadow: var(--shadow-lg);
    transform: translateY(-5px);
}

.card-dark {
    background-color: var(--noir-pur);
    color: var(--blanc-pur);
    border-color: var(--noir-pur);
}

.card-title {
    font-size: var(--text-2xl);
    margin-bottom: var(--spacing-sm);
}

.card-description {
    color: var(--gris-fonce);
    line-height: 1.6;
}

/* ========================================
   GRID SYSTEM
   ======================================== */
.grid {
    display: grid;
    gap: var(--spacing-lg);
}

.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);
}

/* ========================================
   HERO SECTION
   ======================================== */
.hero {
    min-height: 80vh;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    padding: var(--spacing-3xl) 0;
    background-color: var(--noir-pur);
    color: var(--blanc-pur);
}

.hero-title {
    font-size: clamp(2.5rem, 5vw, 4rem);
    font-family: var(--font-secondary);
    color: var(--blanc-pur);
    margin-bottom: var(--spacing-md);
    line-height: 1.1;
}

.hero-subtitle {
    font-size: var(--text-xl);
    color: var(--gris-clair);
    margin-bottom: var(--spacing-xl);
    max-width: 800px;
    margin-left: auto;
    margin-right: auto;
}

.hero-cta {
    display: flex;
    gap: var(--spacing-md);
    justify-content: center;
    flex-wrap: wrap;
}

/* ========================================
   FOOTER
   ======================================== */
.main-footer {
    background-color: var(--noir-pur);
    color: var(--blanc-pur);
    padding: var(--spacing-3xl) 0 var(--spacing-lg);
    margin-top: var(--spacing-3xl);
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-xl);
    margin-bottom: var(--spacing-xl);
}

.footer-title {
    color: var(--blanc-pur);
    font-size: var(--text-xl);
    margin-bottom: var(--spacing-md);
    font-weight: 700;
}

.footer-description {
    color: var(--gris-clair);
    line-height: 1.6;
}

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

.footer-links li {
    margin-bottom: var(--spacing-xs);
}

.footer-links a {
    color: var(--gris-clair);
    transition: color var(--transition-fast);
}

.footer-links a:hover {
    color: var(--blanc-pur);
    opacity: 1;
}

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

.footer-contact li {
    margin-bottom: var(--spacing-sm);
    color: var(--gris-clair);
}

.footer-contact strong {
    display: block;
    color: var(--blanc-pur);
    margin-bottom: 0.25rem;
}

.footer-contact a {
    color: var(--gris-clair);
}

.footer-social {
    display: flex;
    gap: var(--spacing-md);
    margin-top: var(--spacing-md);
}

.footer-social a {
    color: var(--blanc-pur);
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    border: 1px solid var(--gris-fonce);
    transition: all var(--transition-fast);
}

.footer-social a:hover {
    background-color: var(--blanc-pur);
    color: var(--noir-pur);
    opacity: 1;
}

.footer-bottom {
    border-top: 1px solid var(--gris-fonce);
    padding-top: var(--spacing-lg);
    text-align: center;
}

.footer-copyright {
    color: var(--gris-clair);
    font-size: 14px;
}

.footer-copyright .separator {
    margin: 0 var(--spacing-xs);
}

.footer-tagline {
    color: var(--gris-moyen);
    font-size: 14px;
    margin-top: var(--spacing-xs);
    font-style: italic;
}

.footer-logo-img {
    max-width: 150px;
    margin-top: var(--spacing-md);
    filter: invert(1);
}

/* ========================================
   BACK TO TOP BUTTON
   ======================================== */
.back-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    background-color: var(--noir-pur);
    color: var(--blanc-pur);
    width: 50px;
    height: 50px;
    border: none;
    cursor: pointer;
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-normal);
    z-index: 999;
    display: flex;
    align-items: center;
    justify-content: center;
}

.back-to-top.visible {
    opacity: 1;
    visibility: visible;
}

.back-to-top:hover {
    background-color: var(--gris-fonce);
}

/* ========================================
   RESPONSIVE DESIGN - MOBILE FIRST
   ======================================== */

/* Tablette */
@media (max-width: 768px) {
    h1 {
        font-size: var(--text-5xl);
    }

    h2 {
        font-size: var(--text-4xl);
    }

    h3 {
        font-size: var(--text-2xl);
    }

    .nav-menu {
        position: fixed;
        left: -100%;
        top: 70px;
        flex-direction: column;
        background-color: var(--blanc-pur);
        width: 100%;
        text-align: center;
        transition: left var(--transition-normal);
        box-shadow: var(--shadow-lg);
        padding: var(--spacing-lg) 0;
        gap: 0;
        z-index: 1000;
        max-height: calc(100vh - 70px);
        overflow-y: auto;
    }

    .nav-menu.active {
        left: 0;
    }

    .nav-item {
        width: 100%;
        padding: var(--spacing-sm) 0;
        border-bottom: 1px solid var(--gris-clair);
    }

    .nav-link {
        display: block;
        padding: var(--spacing-md);
        border-bottom: none !important;
    }

    .nav-link:hover,
    .nav-link.active {
        background-color: var(--gris-tres-clair);
    }

    .nav-cta {
        margin-top: var(--spacing-sm);
    }

    .nav-cta .btn {
        margin: 0;
        display: block;
        width: 90%;
        margin: 0 auto;
    }

    .nav-toggle {
        display: flex;
    }

    .grid-cols-2,
    .grid-cols-3,
    .grid-cols-4 {
        grid-template-columns: 1fr;
    }

    .footer-content {
        grid-template-columns: 1fr;
    }
}

/* Mobile */
@media (max-width: 480px) {
    .container {
        padding: 0 var(--spacing-sm);
    }

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

    .btn {
        width: 100%;
        display: block;
    }

    .hero-cta {
        flex-direction: column;
    }
}

/* Desktop large */
@media (min-width: 1280px) {
    .container {
        padding: 0 var(--spacing-xl);
    }
}

/* ========================================
   UTILITY CLASSES
   ======================================== */
.text-center {
    text-align: center;
}

.text-left {
    text-align: left;
}

.text-right {
    text-align: right;
}

.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-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); }

.hidden {
    display: none;
}

.visible {
    display: block;
}

/* ========================================
   LIVE DEMO - ANIMATED CHAT
   ======================================== */
.live-demo-section {
    background-color: var(--gris-tres-clair);
    padding: var(--spacing-3xl) 0;
}

.demo-tabs {
    display: flex;
    justify-content: center;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-xl);
    flex-wrap: wrap;
}

.demo-tab {
    background-color: var(--blanc-pur);
    color: var(--noir-pur);
    border: 2px solid var(--gris-clair);
    padding: var(--spacing-sm) var(--spacing-lg);
    cursor: pointer;
    font-weight: 600;
    transition: all var(--transition-fast);
    border-radius: 8px;
}

.demo-tab:hover {
    border-color: var(--gris-moyen);
}

.demo-tab.active {
    background-color: var(--noir-pur);
    color: var(--blanc-pur);
    border-color: var(--noir-pur);
}

.demo-content {
    display: none;
    animation: fadeIn 0.5s ease;
}

.demo-content.active {
    display: block;
}

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

.demo-header {
    background-color: var(--blanc-pur);
    padding: var(--spacing-lg);
    border-radius: 12px 12px 0 0;
    border-bottom: 2px solid var(--gris-clair);
}

.demo-title {
    font-size: var(--text-2xl);
    margin-bottom: var(--spacing-xs);
}

.demo-context {
    color: var(--gris-moyen);
    font-style: italic;
}

.chat-container {
    background-color: var(--blanc-pur);
    padding: var(--spacing-xl);
    border-radius: 0 0 12px 12px;
    min-height: 400px;
    max-width: 900px;
    margin: 0 auto;
    box-shadow: var(--shadow-lg);
}

.chat-message {
    display: flex;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-lg);
    opacity: 0;
    animation: slideIn 0.5s ease forwards;
}

.chat-message.user {
    flex-direction: row-reverse;
}

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

.chat-message.user {
    animation: slideInRight 0.5s ease forwards;
}

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

.chat-avatar {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background-color: var(--noir-pur);
    color: var(--blanc-pur);
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: bold;
    flex-shrink: 0;
}

.chat-message.user .chat-avatar {
    background-color: var(--gris-fonce);
    border: 2px solid var(--noir-pur);
}

.chat-bubble {
    max-width: 70%;
    padding: var(--spacing-md);
    border-radius: 12px;
    background-color: var(--gris-tres-clair);
    position: relative;
}

.chat-message.user .chat-bubble {
    background-color: var(--gris-fonce);
    color: var(--blanc-pur);
    font-weight: 500;
}

.chat-bubble p {
    margin: 0;
    line-height: 1.6;
    white-space: pre-wrap;
}

.typing-indicator {
    display: none;
    align-items: center;
    gap: var(--spacing-xs);
    padding: var(--spacing-sm) var(--spacing-md);
}

.typing-indicator.active {
    display: flex;
}

.typing-dot {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background-color: var(--gris-moyen);
    animation: typing 1.4s infinite;
}

.typing-dot:nth-child(2) {
    animation-delay: 0.2s;
}

.typing-dot:nth-child(3) {
    animation-delay: 0.4s;
}

@keyframes typing {
    0%, 60%, 100% {
        transform: translateY(0);
        opacity: 0.7;
    }
    30% {
        transform: translateY(-10px);
        opacity: 1;
    }
}

.demo-controls {
    text-align: center;
    margin-top: var(--spacing-lg);
    padding-top: var(--spacing-lg);
    border-top: 1px solid var(--gris-clair);
}

.demo-control-btn {
    background-color: var(--noir-pur);
    color: var(--blanc-pur);
    border: none;
    padding: var(--spacing-sm) var(--spacing-lg);
    cursor: pointer;
    font-weight: 600;
    border-radius: 8px;
    margin: 0 var(--spacing-xs);
    transition: all var(--transition-fast);
}

.demo-control-btn:hover {
    background-color: var(--gris-fonce);
}

.demo-control-btn:disabled {
    background-color: var(--gris-clair);
    color: var(--gris-moyen);
    cursor: not-allowed;
}

/* ========================================
   HOW WE WORK SECTION
   ======================================== */
.how-we-work-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--spacing-xl);
    margin-top: var(--spacing-xl);
}

.work-card {
    background-color: var(--blanc-pur);
    padding: var(--spacing-xl);
    border-left: 4px solid var(--noir-pur);
    transition: all var(--transition-normal);
}

.work-card:hover {
    transform: translateX(10px);
    box-shadow: var(--shadow-lg);
}

.work-card-icon {
    font-size: var(--text-4xl);
    margin-bottom: var(--spacing-md);
}

.work-card-title {
    font-size: var(--text-xl);
    margin-bottom: var(--spacing-sm);
    color: var(--noir-pur);
}

.work-card-desc {
    color: var(--gris-fonce);
    line-height: 1.6;
}

/* ========================================
   TECH PIPELINE
   ======================================== */
.tech-pipeline {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-top: var(--spacing-xl);
    position: relative;
    padding: var(--spacing-xl) 0;
}

.tech-pipeline::before {
    content: '';
    position: absolute;
    top: 50px;
    left: 0;
    right: 0;
    height: 2px;
    background-color: var(--gris-clair);
    z-index: 0;
}

.pipeline-step {
    flex: 1;
    text-align: center;
    position: relative;
    z-index: 1;
}

.pipeline-step-number {
    width: 60px;
    height: 60px;
    background-color: var(--noir-pur);
    color: var(--blanc-pur);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: var(--text-2xl);
    font-weight: bold;
    margin: 0 auto var(--spacing-md);
    border: 4px solid var(--blanc-pur);
    box-shadow: var(--shadow-md);
}

.pipeline-step-title {
    font-weight: 700;
    margin-bottom: var(--spacing-xs);
}

.pipeline-step-desc {
    color: var(--gris-moyen);
    font-size: 14px;
}

/* Responsive for pipeline */
@media (max-width: 768px) {
    .tech-pipeline {
        flex-direction: column;
        align-items: center;
    }

    .tech-pipeline::before {
        display: none;
    }

    .pipeline-step {
        margin-bottom: var(--spacing-xl);
    }

    .chat-bubble {
        max-width: 85%;
    }

    .demo-tabs {
        flex-direction: column;
    }

    .demo-tab {
        width: 100%;
    }
}