/* ============================================================
   StudentAI.fr — Warm Organic Design System
   "Learning as a Living Organism"
   Colors: Warm earth tones + sage green + forest accents
   Typography: Playfair Display + Poppins + Crimson Text
============================================================ */

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

:root {
  --color-cream: #F5EDE4;
  --color-sage: #A4C7A1;
  --color-terracotta: #D4796F;
  --color-gold: #E8C547;
  --color-forest: #3A5C3A;
  --color-warm-brown: #8B7355;
  --color-light-brown: #D4A574;
  --color-soft-green: #7FA85C;
  --color-text: #2D2D2D;
  --color-text-light: #666666;

  --spacing-xs: 0.5rem;
  --spacing-sm: 1rem;
  --spacing-md: 1.5rem;
  --spacing-lg: 2.5rem;
  --spacing-xl: 4rem;
  --spacing-2xl: 6rem;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: 'Poppins', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  color: var(--color-text);
  background-color: var(--color-cream);
  line-height: 1.6;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--spacing-lg);
}

/* ============================================================
   TYPOGRAPHY
============================================================ */
h1, h2, h3 {
  font-family: 'Playfair Display', serif;
  font-weight: 700;
  line-height: 1.2;
  margin-bottom: var(--spacing-md);
  color: var(--color-forest);
}

h1 {
  font-size: clamp(2.5rem, 6vw, 4rem);
}

h2 {
  font-size: clamp(1.8rem, 4vw, 3rem);
}

h3 {
  font-size: 1.5rem;
}

h4 {
  font-size: 1.1rem;
  font-weight: 600;
  margin-bottom: var(--spacing-sm);
}

p {
  font-size: 1rem;
  color: var(--color-text-light);
  margin-bottom: var(--spacing-md);
  line-height: 1.8;
}

a {
  color: var(--color-forest);
  text-decoration: none;
  transition: color 0.3s ease;
}

a:hover {
  color: var(--color-soft-green);
}

/* ============================================================
   BUTTONS
============================================================ */
.btn {
  display: inline-block;
  padding: var(--spacing-sm) var(--spacing-md);
  border-radius: 50px;
  font-weight: 600;
  font-size: 1rem;
  border: none;
  cursor: pointer;
  transition: all 0.3s ease;
  text-align: center;
}

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

.btn-primary:hover {
  background-color: var(--color-soft-green);
  border-color: var(--color-soft-green);
  transform: translateY(-2px);
  box-shadow: 0 8px 20px rgba(127, 168, 92, 0.25);
}

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

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

.btn-ghost {
  background-color: transparent;
  color: var(--color-text);
  border: 2px solid var(--color-text-light);
}

.btn-ghost:hover {
  border-color: var(--color-forest);
  color: var(--color-forest);
}

.btn-small {
  padding: 0.6rem 1.2rem;
  font-size: 0.9rem;
}

.btn-large {
  padding: 1.2rem 2.5rem;
  font-size: 1.1rem;
}

/* ============================================================
   HEADER & NAVIGATION
============================================================ */
.header {
  position: sticky;
  top: 0;
  z-index: 100;
  background-color: var(--color-cream);
  border-bottom: 1px solid rgba(58, 92, 58, 0.1);
  transition: all 0.3s ease;
}

.header.scrolled {
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.08);
  background-color: rgba(245, 237, 228, 0.98);
  backdrop-filter: blur(5px);
}

.header-content {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--spacing-md) 0;
}

.logo {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--color-forest);
  transition: all 0.3s ease;
}

.logo-symbol {
  font-size: 1.8rem;
}

.logo-text {
  letter-spacing: -0.5px;
}

.logo:hover {
  transform: scale(1.05);
}

.nav {
  display: flex;
  gap: var(--spacing-lg);
  align-items: center;
}

.nav-link {
  font-weight: 500;
  color: var(--color-text-light);
  transition: all 0.3s ease;
  position: relative;
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background-color: var(--color-soft-green);
  transition: width 0.3s ease;
}

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

.header-actions {
  display: flex;
  gap: var(--spacing-md);
  align-items: center;
}

.btn-nav-toggle {
  display: none;
  flex-direction: column;
  gap: 6px;
  background: none;
  border: none;
  cursor: pointer;
  padding: var(--spacing-sm);
}

.btn-nav-toggle span {
  width: 24px;
  height: 2.5px;
  background-color: var(--color-text);
  border-radius: 2px;
  transition: all 0.3s ease;
}

/* ============================================================
   SECTION HEADER
============================================================ */
.section-header {
  text-align: center;
  margin-bottom: var(--spacing-2xl);
}

.section-header h2 {
  margin-bottom: var(--spacing-md);
}

.section-header p {
  font-size: 1.1rem;
  color: var(--color-text-light);
  max-width: 600px;
  margin: 0 auto;
}

/* ============================================================
   SECTION 1: HERO
============================================================ */
.hero {
  position: relative;
  padding: var(--spacing-2xl) 0;
  background-color: var(--color-cream);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
}

.hero-content {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--spacing-2xl);
  align-items: center;
}

.hero-text {
  animation: fadeInUp 0.8s ease;
}

.hero-title {
  font-size: clamp(2.5rem, 5vw, 3.5rem);
  line-height: 1.1;
  color: var(--color-forest);
  margin-bottom: var(--spacing-lg);
}

.hero-title .line-1,
.hero-title .line-2 {
  display: block;
}

.hero-subtitle {
  font-size: 1.1rem;
  color: var(--color-text-light);
  margin-bottom: var(--spacing-lg);
  line-height: 1.8;
}

.hero-ctas {
  display: flex;
  gap: var(--spacing-md);
  flex-wrap: wrap;
}

.hero-visual {
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 400px;
}

.seed-plant {
  width: 100%;
  max-width: 300px;
  height: auto;
  animation: float 4s ease-in-out infinite;
}

.seed-plant .leaf {
  animation: leafFloat 3s ease-in-out infinite;
  transform-origin: center;
}

.seed-plant .leaf-1 {
  animation-delay: 0s;
}

.seed-plant .leaf-2 {
  animation-delay: 0.3s;
}

.seed-plant .leaf-3 {
  animation-delay: 0.6s;
}

.seed-plant .leaf-4 {
  animation-delay: 0.9s;
}

.seed-plant .leaf-5 {
  animation-delay: 1.2s;
}

.seed-plant .leaf-6 {
  animation-delay: 1.5s;
}

.seed-plant .bud {
  animation: budBloom 4s ease-out forwards;
}

.scroll-indicator {
  position: absolute;
  bottom: 40px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--spacing-sm);
  color: var(--color-text-light);
  animation: bounce 2s ease-in-out infinite;
}

.scroll-arrow {
  width: 24px;
  height: 24px;
  stroke-width: 2;
  color: var(--color-soft-green);
}

/* ============================================================
   SECTION 2: GROWTH STORY
============================================================ */
.growth-story {
  padding: var(--spacing-2xl) 0;
  background: linear-gradient(to bottom, var(--color-cream), rgba(164, 199, 161, 0.1));
}

.paths-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: var(--spacing-2xl);
}

.path-card {
  background-color: white;
  padding: var(--spacing-lg);
  border-radius: 20px;
  border: 1px solid rgba(58, 92, 58, 0.15);
  transition: all 0.4s ease;
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.05);
}

.path-card:hover {
  transform: translateY(-8px);
  box-shadow: 0 12px 35px rgba(127, 168, 92, 0.15);
  border-color: var(--color-soft-green);
}

.path-icon {
  width: 80px;
  height: 80px;
  margin-bottom: var(--spacing-md);
  display: flex;
  align-items: center;
  justify-content: center;
}

.path-icon svg {
  width: 100%;
  height: 100%;
  filter: drop-shadow(0 4px 10px rgba(0, 0, 0, 0.08));
}

.path-card h3 {
  color: var(--color-forest);
  margin-bottom: var(--spacing-md);
}

.path-card p {
  color: var(--color-text-light);
  margin-bottom: var(--spacing-md);
}

.path-features {
  list-style: none;
  padding-left: 0;
}

.path-features li {
  padding-left: 1.5rem;
  position: relative;
  color: var(--color-text-light);
  margin-bottom: 0.75rem;
  font-size: 0.95rem;
}

.path-features li::before {
  content: '✓';
  position: absolute;
  left: 0;
  color: var(--color-soft-green);
  font-weight: bold;
}

/* ============================================================
   SECTION 3: HOW MIND WORKS
============================================================ */
.how-mind-works {
  padding: var(--spacing-2xl) 0;
  background-color: white;
}

.mind-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: var(--spacing-xl);
}

.mind-card {
  text-align: center;
  padding: var(--spacing-lg);
}

.mind-visual {
  height: 200px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: var(--spacing-lg);
  background-color: rgba(245, 237, 228, 0.6);
  border-radius: 15px;
  animation: drift 5s ease-in-out infinite;
}

.mind-card-1 .mind-visual {
  animation-delay: 0s;
}

.mind-card-2 .mind-visual {
  animation-delay: 1s;
}

.mind-card-3 .mind-visual {
  animation-delay: 2s;
}

.mind-visual svg {
  width: 100%;
  max-width: 180px;
  height: auto;
}

.mind-card h3 {
  color: var(--color-forest);
  font-size: 1.3rem;
  margin-bottom: 0.5rem;
}

.mind-card p {
  font-size: 1rem;
  color: var(--color-text-light);
  margin-bottom: var(--spacing-md);
}

.seo-keyword {
  display: inline-block;
  background-color: rgba(164, 199, 161, 0.2);
  color: var(--color-forest);
  padding: 0.4rem 0.8rem;
  border-radius: 20px;
  font-size: 0.85rem;
  font-weight: 600;
}

/* ============================================================
   SECTION 4: ECOSYSTEM
============================================================ */
.ecosystem {
  padding: var(--spacing-2xl) 0;
  background: linear-gradient(to bottom, rgba(164, 199, 161, 0.05), var(--color-cream));
}

.stories-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: var(--spacing-xl);
}

.story-card {
  background-color: white;
  padding: var(--spacing-lg);
  border-radius: 15px;
  border: 1px solid rgba(58, 92, 58, 0.1);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.04);
  transition: all 0.3s ease;
}

.story-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 8px 20px rgba(127, 168, 92, 0.1);
}

.story-header {
  display: flex;
  gap: var(--spacing-md);
  margin-bottom: var(--spacing-md);
}

.story-avatar {
  width: 50px;
  height: 50px;
  border-radius: 50%;
  object-fit: cover;
}

.story-info h4 {
  margin-bottom: 0.25rem;
  color: var(--color-forest);
}

.story-info p {
  font-size: 0.85rem;
  color: var(--color-text-light);
  margin: 0;
}

.story-progress {
  margin-bottom: var(--spacing-md);
}

.progress-bar {
  width: 100%;
  height: 6px;
  background-color: rgba(164, 199, 161, 0.2);
  border-radius: 10px;
  overflow: hidden;
  margin-bottom: 0.4rem;
}

.progress-fill {
  height: 100%;
  background: linear-gradient(to right, var(--color-soft-green), var(--color-sage));
  border-radius: 10px;
  animation: fillAnimation 1.5s ease-out;
}

.story-progress > span {
  font-size: 0.8rem;
  color: var(--color-text-light);
}

.story-quote {
  color: var(--color-text);
  font-style: italic;
  font-size: 0.95rem;
  margin: 0;
  line-height: 1.6;
}

/* ============================================================
   SECTION 5: MYSTERY
============================================================ */
.mystery {
  padding: var(--spacing-2xl) 0;
  background-color: white;
}

.mystery-content {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--spacing-2xl);
  align-items: center;
}

.mystery-text h2 {
  color: var(--color-forest);
  margin-bottom: var(--spacing-md);
}

.mystery-text p {
  color: var(--color-text-light);
  margin-bottom: var(--spacing-md);
  line-height: 1.8;
}

.mystery-reveal {
  padding: var(--spacing-md);
  background-color: rgba(232, 197, 71, 0.1);
  border-left: 4px solid var(--color-gold);
  border-radius: 8px;
}

.mystery-visual {
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 300px;
}

.break-illustration {
  width: 100%;
  max-width: 300px;
  height: auto;
  animation: float 4s ease-in-out infinite;
}

/* ============================================================
   SECTION 6: PRICING
============================================================ */
.pricing {
  padding: var(--spacing-2xl) 0;
  background: linear-gradient(135deg, rgba(164, 199, 161, 0.1) 0%, rgba(245, 237, 228, 0.8) 100%);
}

.pricing-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: var(--spacing-xl);
}

.pricing-card {
  background-color: white;
  padding: var(--spacing-lg);
  border-radius: 20px;
  border: 2px solid rgba(58, 92, 58, 0.1);
  text-align: center;
  transition: all 0.4s ease;
  position: relative;
  overflow: hidden;
}

.pricing-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(to right, var(--color-soft-green), var(--color-sage));
  transform: translateX(-100%);
  transition: transform 0.4s ease;
}

.pricing-card:hover::before {
  transform: translateX(0);
}

.pricing-card:hover {
  transform: translateY(-12px);
  box-shadow: 0 16px 40px rgba(127, 168, 92, 0.2);
  border-color: var(--color-soft-green);
}

.pricing-featured {
  border: 2px solid var(--color-soft-green);
  transform: scale(1.05);
}

.pricing-featured:hover {
  transform: scale(1.05) translateY(-12px);
}

.pricing-badge {
  display: inline-block;
  background-color: var(--color-gold);
  color: var(--color-text);
  padding: 0.4rem 1rem;
  border-radius: 50px;
  font-size: 0.8rem;
  font-weight: 700;
  margin-bottom: var(--spacing-md);
  text-transform: uppercase;
  letter-spacing: 1px;
}

.pricing-tier {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--color-forest);
  margin-bottom: var(--spacing-md);
}

.pricing-price {
  margin-bottom: var(--spacing-md);
}

.currency {
  font-size: 2.5rem;
  font-weight: 800;
  color: var(--color-forest);
}

.currency-unit {
  font-size: 1rem;
  color: var(--color-text-light);
  font-weight: 500;
}

.pricing-desc {
  color: var(--color-text-light);
  margin-bottom: var(--spacing-md);
  font-size: 1rem;
}

.pricing-features {
  list-style: none;
  padding-left: 0;
  margin-bottom: var(--spacing-lg);
  text-align: left;
  background-color: rgba(245, 237, 228, 0.4);
  padding: var(--spacing-md);
  border-radius: 12px;
}

.pricing-features li {
  padding: 0.5rem 0;
  color: var(--color-text-light);
  padding-left: 1.5rem;
  position: relative;
}

.pricing-features li::before {
  content: '→';
  position: absolute;
  left: 0;
  color: var(--color-soft-green);
  font-weight: bold;
}

.pricing-card .btn {
  width: 100%;
}

/* ============================================================
   SECTION 7: COMMITMENT
============================================================ */
.commitment {
  padding: var(--spacing-2xl) 0;
  background-color: white;
}

.commitment-box {
  background: linear-gradient(135deg, rgba(164, 199, 161, 0.15) 0%, rgba(212, 165, 116, 0.1) 100%);
  padding: var(--spacing-2xl);
  border-radius: 25px;
  border: 2px solid rgba(58, 92, 58, 0.1);
}

.commitment-box h2 {
  text-align: center;
  margin-bottom: var(--spacing-2xl);
  color: var(--color-forest);
}

.promises {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: var(--spacing-xl);
  margin-bottom: var(--spacing-2xl);
}

.promise {
  position: relative;
  padding: var(--spacing-lg);
  text-align: center;
}

.promise p {
  font-size: 1.05rem;
  color: var(--color-text);
  margin-bottom: var(--spacing-md);
  line-height: 1.6;
  font-weight: 500;
}

.promise-icon {
  font-size: 2.5rem;
  display: block;
  opacity: 0.7;
}

.commitment-cta {
  text-align: center;
}

.commitment-question {
  font-size: 1.3rem;
  font-weight: 600;
  color: var(--color-forest);
  margin-bottom: var(--spacing-md);
}

/* ============================================================
   FOOTER
============================================================ */
.footer {
  background-color: var(--color-forest);
  color: white;
  padding: var(--spacing-2xl) 0 var(--spacing-lg);
}

.footer-header {
  text-align: center;
  margin-bottom: var(--spacing-2xl);
  padding-bottom: var(--spacing-2xl);
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.footer-header h3 {
  color: white;
  font-size: 2rem;
  margin-bottom: var(--spacing-md);
}

.footer-header p {
  color: rgba(255, 255, 255, 0.8);
}

.footer-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: var(--spacing-lg);
  margin-bottom: var(--spacing-2xl);
}

.footer-section h4 {
  color: white;
  margin-bottom: var(--spacing-md);
  font-weight: 700;
}

.footer-section a {
  display: block;
  color: rgba(255, 255, 255, 0.7);
  margin-bottom: 0.75rem;
  transition: color 0.3s ease;
}

.footer-section a:hover {
  color: var(--color-gold);
}

.footer-section p {
  color: rgba(255, 255, 255, 0.7);
  font-size: 0.95rem;
}

.newsletter-form {
  display: flex;
  gap: var(--spacing-sm);
  margin-top: var(--spacing-md);
}

.newsletter-form input {
  flex: 1;
  padding: 0.75rem 1rem;
  border: none;
  border-radius: 25px;
  background-color: white;
  color: var(--color-text);
  font-size: 0.95rem;
}

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

.footer-bottom {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-top: var(--spacing-lg);
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  flex-wrap: wrap;
  gap: var(--spacing-lg);
}

.footer-bottom p {
  color: rgba(255, 255, 255, 0.6);
  font-size: 0.9rem;
  margin: 0;
}

.footer-socials {
  display: flex;
  gap: var(--spacing-lg);
}

.footer-socials a {
  color: rgba(255, 255, 255, 0.7);
  transition: color 0.3s ease;
}

.footer-socials a:hover {
  color: var(--color-gold);
}

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

@keyframes float {
  0%, 100% {
    transform: translateY(0px);
  }
  50% {
    transform: translateY(-20px);
  }
}

@keyframes leafFloat {
  0%, 100% {
    opacity: 0.8;
    transform: rotate(0deg);
  }
  50% {
    opacity: 1;
    transform: rotate(3deg);
  }
}

@keyframes budBloom {
  0% {
    opacity: 0;
    r: 0;
  }
  50% {
    opacity: 0;
  }
  100% {
    opacity: 0.9;
    r: 12;
  }
}

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

@keyframes drift {
  0%, 100% {
    transform: translateY(0px);
  }
  50% {
    transform: translateY(-15px);
  }
}

@keyframes fillAnimation {
  from {
    width: 0;
  }
}

/* ============================================================
   RESPONSIVE DESIGN
============================================================ */
@media (max-width: 768px) {
  :root {
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;
  }

  .nav {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    flex-direction: column;
    gap: var(--spacing-md);
    background-color: white;
    padding: var(--spacing-lg);
    border-bottom: 1px solid rgba(58, 92, 58, 0.1);
  }

  .nav.mobile-open {
    display: flex;
  }

  .btn-nav-toggle {
    display: flex;
  }

  .hero-content {
    grid-template-columns: 1fr;
    gap: var(--spacing-lg);
  }

  .hero-visual {
    min-height: 300px;
  }

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

  .footer-bottom {
    flex-direction: column;
    text-align: center;
  }

  .footer-socials {
    justify-content: center;
  }

  .paths-grid,
  .mind-grid,
  .stories-grid,
  .promises {
    grid-template-columns: 1fr;
  }

  .pricing-featured {
    transform: scale(1);
  }

  .pricing-featured:hover {
    transform: scale(1) translateY(-12px);
  }

  h1 {
    font-size: 2rem;
  }

  h2 {
    font-size: 1.5rem;
  }
}

@media (max-width: 480px) {
  .container {
    padding: 0 var(--spacing-md);
  }

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

  .hero-title {
    font-size: 1.8rem;
  }

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

  .hero-ctas .btn {
    width: 100%;
  }

  .pricing-grid {
    gap: var(--spacing-lg);
  }

  .newsletter-form {
    flex-direction: column;
  }

  .newsletter-form button {
    width: 100%;
  }

  .section-header {
    margin-bottom: var(--spacing-lg);
  }

  .footer-bottom {
    font-size: 0.85rem;
  }
}

/* ============================================================
   ACCESSIBILITY & UTILITIES
============================================================ */
[data-aos] {
  opacity: 0;
}

[data-aos].aos-animate {
  opacity: 1;
}

/* Focus states for keyboard navigation */
.btn:focus,
.nav-link:focus,
a:focus {
  outline: 2px solid var(--color-soft-green);
  outline-offset: 2px;
}

/* Smooth transitions for reduced motion preference */
@media (prefers-reduced-motion: reduce) {
  * {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}