/* ===== ThinkDeep Institute - Main Stylesheet ===== */
:root {
  --slate: #4A5568;
  --slate-dark: #2D3748;
  --slate-light: #718096;
  --emerald: #10B981;
  --emerald-dark: #059669;
  --emerald-light: #D1FAE5;
  --white: #FFFFFF;
  --off-white: #F7FAFC;
  --gray-100: #EDF2F7;
  --gray-200: #E2E8F0;
  --gray-300: #CBD5E0;
  --text: #2D3748;
  --text-light: #718096;
  --shadow: 0 4px 20px rgba(0,0,0,0.08);
  --shadow-lg: 0 10px 40px rgba(0,0,0,0.12);
  --radius: 8px;
  --radius-lg: 16px;
  --transition: 0.3s ease;
  --max-width: 1200px;
}

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

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

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
  color: var(--text);
  background: var(--white);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3, h4, h5, h6 {
  font-family: Georgia, 'Times New Roman', serif;
  line-height: 1.3;
  color: var(--slate-dark);
}

h1 { font-size: 2.8rem; }
h2 { font-size: 2.2rem; }
h3 { font-size: 1.5rem; }
h4 { font-size: 1.2rem; }

a { color: var(--emerald); text-decoration: none; transition: color var(--transition); }
a:hover { color: var(--emerald-dark); }

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

.container { max-width: var(--max-width); margin: 0 auto; padding: 0 24px; }

/* ===== Header ===== */
.header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: rgba(255,255,255,0.97);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--gray-200);
  transition: box-shadow var(--transition);
}
.header.scrolled { box-shadow: var(--shadow); }
.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
}
.logo { display: flex; align-items: center; gap: 10px; }
.logo img { height: 40px; width: auto; }
.logo span { font-family: Georgia, serif; font-size: 1.3rem; font-weight: 700; color: var(--slate-dark); }
.logo .accent { color: var(--emerald); }

.nav { display: flex; align-items: center; gap: 32px; }
.nav a {
  color: var(--slate);
  font-size: 0.95rem;
  font-weight: 500;
  position: relative;
  padding: 4px 0;
}
.nav a::after {
  content: '';
  position: absolute;
  bottom: -2px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--emerald);
  transition: width var(--transition);
}
.nav a:hover { color: var(--emerald); }
.nav a:hover::after { width: 100%; }

.nav-cta {
  background: var(--emerald);
  color: var(--white) !important;
  padding: 10px 24px;
  border-radius: var(--radius);
  font-weight: 600;
}
.nav-cta::after { display: none !important; }
.nav-cta:hover { background: var(--emerald-dark); color: var(--white) !important; }

/* Hamburger */
.hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
  z-index: 1001;
}
.hamburger span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--slate-dark);
  transition: var(--transition);
  border-radius: 2px;
}
.hamburger.active span:nth-child(1) { transform: rotate(45deg) translate(5px, 5px); }
.hamburger.active span:nth-child(2) { opacity: 0; }
.hamburger.active span:nth-child(3) { transform: rotate(-45deg) translate(5px, -5px); }

/* ===== Buttons ===== */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 32px;
  border-radius: var(--radius);
  font-weight: 600;
  font-size: 1rem;
  cursor: pointer;
  border: none;
  transition: all var(--transition);
  text-decoration: none;
}
.btn-primary { background: var(--emerald); color: var(--white); }
.btn-primary:hover { background: var(--emerald-dark); color: var(--white); transform: translateY(-2px); box-shadow: 0 6px 20px rgba(16,185,129,0.3); }
.btn-secondary { background: transparent; color: var(--emerald); border: 2px solid var(--emerald); }
.btn-secondary:hover { background: var(--emerald); color: var(--white); transform: translateY(-2px); }
.btn-slate { background: var(--slate); color: var(--white); }
.btn-slate:hover { background: var(--slate-dark); color: var(--white); transform: translateY(-2px); }

/* ===== Hero ===== */
.hero {
  padding: 100px 0 80px;
  background: linear-gradient(135deg, var(--off-white) 0%, var(--emerald-light) 100%);
  position: relative;
  overflow: hidden;
}
.hero::before {
  content: '';
  position: absolute;
  top: -50%;
  right: -20%;
  width: 600px;
  height: 600px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(16,185,129,0.08) 0%, transparent 70%);
}
.hero-content { max-width: 700px; position: relative; z-index: 1; }
.hero-badge {
  display: inline-block;
  background: rgba(16,185,129,0.1);
  color: var(--emerald-dark);
  padding: 6px 16px;
  border-radius: 50px;
  font-size: 0.85rem;
  font-weight: 600;
  margin-bottom: 24px;
}
.hero h1 { margin-bottom: 24px; font-size: 3.2rem; }
.hero h1 .accent { color: var(--emerald); }
.hero p { font-size: 1.2rem; color: var(--text-light); margin-bottom: 36px; max-width: 560px; }
.hero-buttons { display: flex; gap: 16px; flex-wrap: wrap; }

/* ===== Section Styles ===== */
.section { padding: 80px 0; }
.section-alt { background: var(--off-white); }
.section-dark { background: var(--slate-dark); color: var(--white); }
.section-dark h2, .section-dark h3, .section-dark h4 { color: var(--white); }
.section-header { text-align: center; margin-bottom: 56px; }
.section-header h2 { margin-bottom: 16px; }
.section-header p { color: var(--text-light); font-size: 1.1rem; max-width: 600px; margin: 0 auto; }
.section-dark .section-header p { color: var(--gray-300); }

/* ===== Cards ===== */
.card {
  background: var(--white);
  border-radius: var(--radius-lg);
  padding: 32px;
  box-shadow: var(--shadow);
  transition: all var(--transition);
  border: 1px solid var(--gray-200);
}
.card:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); }

/* ===== Grid ===== */
.grid-2 { display: grid; grid-template-columns: repeat(2, 1fr); gap: 32px; }
.grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 32px; }
.grid-4 { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }

/* ===== Stats ===== */
.stats { display: grid; grid-template-columns: repeat(4, 1fr); gap: 32px; padding: 60px 0; }
.stat { text-align: center; }
.stat-number { font-size: 2.8rem; font-weight: 700; color: var(--emerald); font-family: Georgia, serif; }
.stat-label { color: var(--gray-300); font-size: 0.95rem; margin-top: 4px; }

/* ===== Course Cards ===== */
.course-card { position: relative; overflow: hidden; }
.course-icon {
  width: 56px;
  height: 56px;
  background: var(--emerald-light);
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
}
.course-icon svg { width: 28px; height: 28px; color: var(--emerald); }
.course-card h3 { margin-bottom: 12px; font-size: 1.25rem; }
.course-card p { color: var(--text-light); font-size: 0.95rem; margin-bottom: 20px; }
.course-meta { display: flex; justify-content: space-between; align-items: center; padding-top: 16px; border-top: 1px solid var(--gray-200); }
.course-price { font-size: 1.3rem; font-weight: 700; color: var(--emerald); }
.course-duration { font-size: 0.85rem; color: var(--text-light); }

/* ===== Methodology ===== */
.methodology-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 40px; align-items: center; }
.methodology-steps { display: flex; flex-direction: column; gap: 24px; }
.method-step {
  display: flex; gap: 20px; align-items: flex-start;
  padding: 20px;
  border-radius: var(--radius);
  transition: background var(--transition);
}
.method-step:hover { background: var(--off-white); }
.method-number {
  width: 44px; height: 44px; min-width: 44px;
  background: var(--emerald);
  color: var(--white);
  border-radius: 50%;
  display: flex; align-items: center; justify-content: center;
  font-weight: 700;
  font-family: Georgia, serif;
  font-size: 1.1rem;
}
.method-step h4 { margin-bottom: 6px; }
.method-step p { color: var(--text-light); font-size: 0.9rem; }
.methodology-visual {
  background: linear-gradient(135deg, var(--slate-dark), var(--slate));
  border-radius: var(--radius-lg);
  padding: 48px;
  color: var(--white);
  text-align: center;
  min-height: 400px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 24px;
}
.methodology-visual svg { width: 120px; height: 120px; opacity: 0.9; }
.methodology-visual h3 { font-size: 1.6rem; }
.methodology-visual p { color: var(--gray-300); max-width: 300px; }

/* ===== Testimonials ===== */
.testimonial-card { padding: 36px; }
.testimonial-stars { display: flex; gap: 4px; margin-bottom: 16px; }
.testimonial-stars svg { width: 18px; height: 18px; fill: #F59E0B; }
.testimonial-text { font-style: italic; color: var(--text-light); margin-bottom: 24px; line-height: 1.8; font-size: 0.95rem; }
.testimonial-author { display: flex; align-items: center; gap: 14px; }
.testimonial-avatar {
  width: 48px; height: 48px;
  background: var(--emerald-light);
  border-radius: 50%;
  display: flex; align-items: center; justify-content: center;
  font-weight: 700;
  color: var(--emerald);
  font-family: Georgia, serif;
}
.testimonial-name { font-weight: 600; color: var(--slate-dark); }
.testimonial-role { font-size: 0.85rem; color: var(--text-light); }

/* ===== Blog Cards ===== */
.blog-card { overflow: hidden; padding: 0; }
.blog-card-img {
  height: 200px;
  background: linear-gradient(135deg, var(--slate), var(--slate-dark));
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
}
.blog-card-img svg { width: 48px; height: 48px; color: var(--emerald); opacity: 0.6; }
.blog-card-body { padding: 28px; }
.blog-tag {
  display: inline-block;
  background: var(--emerald-light);
  color: var(--emerald-dark);
  padding: 4px 12px;
  border-radius: 50px;
  font-size: 0.78rem;
  font-weight: 600;
  margin-bottom: 12px;
}
.blog-card h3 { font-size: 1.15rem; margin-bottom: 10px; }
.blog-card p { color: var(--text-light); font-size: 0.9rem; margin-bottom: 16px; }
.blog-card-footer { display: flex; justify-content: space-between; align-items: center; font-size: 0.82rem; color: var(--text-light); }

/* ===== Pricing ===== */
.pricing-card { text-align: center; position: relative; }
.pricing-card.featured { border: 2px solid var(--emerald); transform: scale(1.05); }
.pricing-card.featured::before {
  content: 'Most Popular';
  position: absolute;
  top: -14px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--emerald);
  color: var(--white);
  padding: 4px 20px;
  border-radius: 50px;
  font-size: 0.82rem;
  font-weight: 600;
}
.pricing-name { font-size: 1.3rem; font-weight: 700; color: var(--slate-dark); margin-bottom: 8px; }
.pricing-price { font-size: 3rem; font-weight: 700; color: var(--emerald); font-family: Georgia, serif; }
.pricing-price span { font-size: 1rem; color: var(--text-light); font-family: -apple-system, sans-serif; }
.pricing-desc { color: var(--text-light); margin: 12px 0 28px; font-size: 0.95rem; }
.pricing-features { list-style: none; text-align: left; margin-bottom: 32px; }
.pricing-features li {
  padding: 10px 0;
  border-bottom: 1px solid var(--gray-100);
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 0.95rem;
  color: var(--text);
}
.pricing-features li svg { width: 18px; height: 18px; color: var(--emerald); flex-shrink: 0; }

/* ===== Team ===== */
.team-card { text-align: center; padding: 40px 28px; }
.team-avatar {
  width: 90px; height: 90px;
  background: linear-gradient(135deg, var(--emerald-light), var(--gray-100));
  border-radius: 50%;
  margin: 0 auto 20px;
  display: flex; align-items: center; justify-content: center;
  font-size: 2rem; font-weight: 700;
  color: var(--emerald);
  font-family: Georgia, serif;
}
.team-card h3 { margin-bottom: 4px; font-size: 1.15rem; }
.team-card .role { color: var(--emerald); font-weight: 600; font-size: 0.9rem; margin-bottom: 12px; }
.team-card p { color: var(--text-light); font-size: 0.9rem; }

/* ===== About ===== */
.about-hero { padding: 80px 0; background: linear-gradient(135deg, var(--off-white), var(--emerald-light)); }
.about-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 60px; align-items: center; }
.about-visual {
  background: linear-gradient(135deg, var(--slate-dark), var(--slate));
  border-radius: var(--radius-lg);
  padding: 60px;
  min-height: 360px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 20px;
  color: var(--white);
  text-align: center;
}
.about-visual svg { width: 80px; height: 80px; opacity: 0.8; }
.values-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 32px; }
.value-card { text-align: center; padding: 36px 24px; }
.value-icon {
  width: 64px; height: 64px;
  background: var(--emerald-light);
  border-radius: 16px;
  display: flex; align-items: center; justify-content: center;
  margin: 0 auto 20px;
}
.value-icon svg { width: 32px; height: 32px; color: var(--emerald); }

/* ===== Contact ===== */
.contact-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 48px; }
.contact-info { display: flex; flex-direction: column; gap: 28px; }
.contact-item { display: flex; gap: 16px; align-items: flex-start; }
.contact-icon {
  width: 48px; height: 48px; min-width: 48px;
  background: var(--emerald-light);
  border-radius: 12px;
  display: flex; align-items: center; justify-content: center;
}
.contact-icon svg { width: 22px; height: 22px; color: var(--emerald); }
.contact-item h4 { margin-bottom: 4px; }
.contact-item p { color: var(--text-light); font-size: 0.95rem; }

.form-group { margin-bottom: 20px; }
.form-group label { display: block; font-weight: 600; margin-bottom: 6px; font-size: 0.95rem; color: var(--slate-dark); }
.form-group input, .form-group select, .form-group textarea {
  width: 100%;
  padding: 12px 16px;
  border: 1px solid var(--gray-300);
  border-radius: var(--radius);
  font-size: 1rem;
  font-family: inherit;
  transition: border-color var(--transition);
  background: var(--white);
}
.form-group input:focus, .form-group select:focus, .form-group textarea:focus {
  outline: none;
  border-color: var(--emerald);
  box-shadow: 0 0 0 3px rgba(16,185,129,0.1);
}
.form-group textarea { resize: vertical; min-height: 140px; }
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }

/* ===== FAQ ===== */
.faq-item {
  border: 1px solid var(--gray-200);
  border-radius: var(--radius);
  margin-bottom: 12px;
  overflow: hidden;
  transition: box-shadow var(--transition);
}
.faq-item:hover { box-shadow: var(--shadow); }
.faq-question {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 20px 24px;
  cursor: pointer;
  background: var(--white);
  border: none;
  width: 100%;
  text-align: left;
  font-size: 1rem;
  font-weight: 600;
  color: var(--slate-dark);
  font-family: inherit;
  transition: background var(--transition);
}
.faq-question:hover { background: var(--off-white); }
.faq-question svg {
  width: 20px; height: 20px;
  color: var(--emerald);
  transition: transform var(--transition);
  flex-shrink: 0;
}
.faq-item.active .faq-question svg { transform: rotate(180deg); }
.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.4s ease, padding 0.4s ease;
}
.faq-item.active .faq-answer { max-height: 400px; }
.faq-answer-inner { padding: 0 24px 20px; color: var(--text-light); line-height: 1.8; }

/* ===== Page Header ===== */
.page-header {
  padding: 60px 0;
  background: linear-gradient(135deg, var(--off-white), var(--emerald-light));
  text-align: center;
}
.page-header h1 { margin-bottom: 12px; }
.page-header p { color: var(--text-light); font-size: 1.1rem; max-width: 600px; margin: 0 auto; }

/* ===== Legal ===== */
.legal-content { max-width: 800px; margin: 0 auto; }
.legal-content h2 { font-size: 1.5rem; margin: 40px 0 16px; color: var(--slate-dark); }
.legal-content h3 { font-size: 1.2rem; margin: 28px 0 12px; }
.legal-content p { margin-bottom: 16px; color: var(--text-light); }
.legal-content ul { margin: 0 0 16px 24px; color: var(--text-light); }
.legal-content ul li { margin-bottom: 8px; }

/* ===== Thank You ===== */
.thank-you-page {
  min-height: 70vh;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 60px 24px;
}
.thank-you-icon {
  width: 80px; height: 80px;
  background: var(--emerald-light);
  border-radius: 50%;
  display: flex; align-items: center; justify-content: center;
  margin: 0 auto 24px;
}
.thank-you-icon svg { width: 40px; height: 40px; color: var(--emerald); }
.thank-you-page h1 { margin-bottom: 16px; }
.thank-you-page p { color: var(--text-light); font-size: 1.1rem; margin-bottom: 8px; }

/* ===== Footer ===== */
.footer { background: var(--slate-dark); color: var(--gray-300); padding: 64px 0 0; }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr 1fr; gap: 40px; margin-bottom: 48px; }
.footer-brand p { margin-top: 16px; font-size: 0.9rem; line-height: 1.8; }
.footer h4 { color: var(--white); font-size: 1rem; margin-bottom: 20px; }
.footer-links { list-style: none; }
.footer-links li { margin-bottom: 10px; }
.footer-links a { color: var(--gray-300); font-size: 0.9rem; }
.footer-links a:hover { color: var(--emerald); }
.footer-bottom {
  border-top: 1px solid rgba(255,255,255,0.1);
  padding: 24px 0;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 12px;
  font-size: 0.85rem;
}
.footer-bottom a { color: var(--gray-300); }
.footer-bottom a:hover { color: var(--emerald); }

/* ===== Animations ===== */
.fade-in {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}
.fade-in.visible { opacity: 1; transform: translateY(0); }
.fade-in-delay-1 { transition-delay: 0.1s; }
.fade-in-delay-2 { transition-delay: 0.2s; }
.fade-in-delay-3 { transition-delay: 0.3s; }
.fade-in-delay-4 { transition-delay: 0.4s; }

/* ===== Responsive ===== */
@media (max-width: 1024px) {
  h1 { font-size: 2.2rem; }
  h2 { font-size: 1.8rem; }
  .hero h1 { font-size: 2.6rem; }
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: repeat(2, 1fr); }
  .stats { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 768px) {
  .hamburger { display: flex; }
  .nav {
    position: fixed;
    top: 0;
    right: -100%;
    width: 280px;
    height: 100vh;
    background: var(--white);
    flex-direction: column;
    padding: 100px 32px 32px;
    gap: 0;
    box-shadow: var(--shadow-lg);
    transition: right var(--transition);
    z-index: 999;
  }
  .nav.open { right: 0; }
  .nav a { padding: 14px 0; width: 100%; border-bottom: 1px solid var(--gray-100); }
  .nav a::after { display: none; }
  .nav-cta { margin-top: 16px; text-align: center; justify-content: center; }
  .overlay {
    display: none;
    position: fixed;
    inset: 0;
    background: rgba(0,0,0,0.4);
    z-index: 998;
  }
  .overlay.active { display: block; }

  h1 { font-size: 1.9rem; }
  .hero { padding: 60px 0 50px; }
  .hero h1 { font-size: 2.1rem; }
  .hero-buttons { flex-direction: column; }
  .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
  .methodology-grid { grid-template-columns: 1fr; }
  .about-grid { grid-template-columns: 1fr; }
  .contact-grid { grid-template-columns: 1fr; }
  .values-grid { grid-template-columns: 1fr; }
  .pricing-card.featured { transform: none; }
  .stats { grid-template-columns: 1fr 1fr; gap: 24px; }
  .form-row { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; }
  .footer-bottom { flex-direction: column; text-align: center; }
  .section { padding: 56px 0; }
}

@media (max-width: 480px) {
  h1 { font-size: 1.6rem; }
  .hero h1 { font-size: 1.8rem; }
  .container { padding: 0 16px; }
  .card { padding: 24px; }
}