@import url('https://fonts.googleapis.com/css2?family=Plus+Jakarta+Sans:wght@400;500;600;700;800&display=swap');

/* CSS Custom Properties / Design System */
:root {
  --primary: #2560ff;
  --primary-hover: #1044db;
  --primary-light: #ebf0ff;
  --primary-rgb: 37, 96, 255;
  
  --text-main: #0f172a;
  --text-muted: #475569;
  --text-light: #64748b;
  
  --bg-main: #ffffff;
  --bg-sub: #f8fafc;
  --bg-card: #ffffff;
  
  --border: #cbd5e1;
  --border-hover: #94a3b8;
  --border-focus: #93c5fd;
  
  --success: #10b981;
  --success-light: #f0fdf4;
  --success-text: #15803d;
  
  --shadow-sm: 0 1px 3px 0 rgba(0, 0, 0, 0.05), 0 1px 2px -1px rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.05), 0 2px 4px -2px rgba(0, 0, 0, 0.05);
  --shadow-lg: 0 10px 25px -5px rgba(37, 96, 255, 0.08), 0 8px 10px -6px rgba(37, 96, 255, 0.08);
  
  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 24px;
  --radius-pill: 9999px;
  
  --transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
  --font-sans: 'Plus Jakarta Sans', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  --max-width: 1200px;
}

/* Global resets & Base styles */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

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

body {
  font-family: var(--font-sans);
  background-color: var(--bg-main);
  color: var(--text-main);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

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

ul, ol {
  list-style: none;
}

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

/* Utility Layout Classes */
.container {
  width: 100%;
  max-width: var(--max-width);
  margin-left: auto;
  margin-right: auto;
  padding-left: 1.5rem;
  padding-right: 1.5rem;
}

/* Header & Navigation */
header {
  position: sticky;
  top: 0;
  z-index: 100;
  background-color: rgba(255, 255, 255, 0.9);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid #e2e8f0;
  transition: var(--transition);
}

.nav-container {
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: 70px;
  position: relative;
}

.logo-wrapper {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  z-index: 101;
}

.logo-img, .footer-logo-img {
  width: 38px;
  height: 38px;
  object-fit: cover;
  background-color: var(--primary-light);
  border-radius: 50%;
  overflow: hidden;
}

.logo-text {
  font-size: 1.25rem;
  font-weight: 800;
  letter-spacing: -0.03em;
  color: var(--primary);
  white-space: nowrap;
}

/* Hamburger toggle styling */
.menu-toggle {
  display: none;
  background: none;
  border: none;
  color: var(--text-main);
  cursor: pointer;
  padding: 0.5rem;
  z-index: 101;
  border-radius: var(--radius-sm);
  transition: var(--transition);
}

.menu-toggle:hover {
  background-color: var(--bg-sub);
}

.menu-toggle svg {
  width: 24px;
  height: 24px;
}

/* Desktop default nav menu */
.nav-menu {
  display: flex;
  align-items: center;
  gap: 1.5rem;
}

.nav-link {
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--text-muted);
}

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

.btn-nav-cta {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background-color: var(--primary);
  color: var(--bg-main) !important;
  font-weight: 700;
  font-size: 0.9rem;
  padding: 0.5rem 1.25rem;
  border-radius: var(--radius-pill);
  box-shadow: 0 4px 10px rgba(37, 96, 255, 0.2);
}

.btn-nav-cta:hover {
  background-color: var(--primary-hover);
  transform: translateY(-1px);
}

/* Mobile responsive menu */
@media (max-width: 767px) {
  .menu-toggle {
    display: block;
  }
  
  .nav-menu {
    display: none;
    flex-direction: column;
    position: absolute;
    top: 70px;
    left: 0;
    width: 100%;
    background-color: var(--bg-main);
    border-bottom: 1px solid #e2e8f0;
    padding: 1.5rem 2rem;
    gap: 1.25rem;
    box-shadow: var(--shadow-md);
    align-items: stretch;
    text-align: center;
    z-index: 100;
  }
  
  .nav-menu.active {
    display: flex;
  }
  
  .nav-menu .nav-link {
    padding: 0.5rem 0;
    font-size: 1.05rem;
    border-bottom: 1px solid #f1f5f9;
  }
  
  .nav-menu .btn-nav-cta {
    width: 100%;
    padding: 0.75rem;
    margin-top: 0.5rem;
  }
}

/* Hero Section */
.hero-section {
  padding-top: 3.5rem;
  padding-bottom: 4.5rem;
  background: radial-gradient(circle at 80% 20%, rgba(37, 96, 255, 0.04) 0%, transparent 60%);
  overflow: hidden;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 3rem;
  align-items: center;
}

.hero-content {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

.hero-badge {
  align-self: flex-start;
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  background-color: var(--primary-light);
  color: var(--primary);
  padding: 0.35rem 0.85rem;
  border-radius: var(--radius-pill);
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0.05em;
  text-transform: uppercase;
}

.hero-badge svg {
  width: 14px;
  height: 14px;
}

.hero-title {
  font-size: 2.5rem;
  line-height: 1.15;
  font-weight: 800;
  letter-spacing: -0.03em;
  color: var(--text-main);
}

.hero-title span {
  color: var(--primary);
}

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

.hero-ctas {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  margin-top: 0.5rem;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.85rem 1.75rem;
  font-weight: 700;
  border-radius: var(--radius-md);
  font-size: 1rem;
  transition: var(--transition);
  cursor: pointer;
  border: 1px solid transparent;
}

.btn-primary {
  background-color: var(--primary);
  color: var(--bg-main);
  box-shadow: 0 4px 14px rgba(37, 96, 255, 0.25);
}

.btn-primary:hover {
  background-color: var(--primary-hover);
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(37, 96, 255, 0.35);
}

.btn-secondary {
  background-color: var(--bg-main);
  color: var(--text-main);
  border-color: #cbd5e1;
  box-shadow: var(--shadow-sm);
}

.btn-secondary:hover {
  border-color: var(--border-hover);
  background-color: var(--bg-sub);
  transform: translateY(-2px);
}

.hero-visual {
  position: relative;
  width: 100%;
}

.video-container {
  position: relative;
  width: 100%;
  aspect-ratio: 16 / 9;
  border-radius: var(--radius-md);
  overflow: hidden;
  box-shadow: var(--shadow-lg), 0 20px 40px -10px rgba(15, 23, 42, 0.1);
  border: 4px solid var(--bg-main);
  background-color: #000;
}

.video-container iframe {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  border: none;
}

/* Stats / Trust Badges Section */
.stats-section {
  padding: 3rem 0;
  background-color: var(--bg-sub);
  border-top: 1px solid #e2e8f0;
  border-bottom: 1px solid #e2e8f0;
}

.stats-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 2rem;
}

@media (min-width: 576px) {
  .stats-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 992px) {
  .stats-grid {
    grid-template-columns: repeat(4, 1fr);
  }
}

.stat-card {
  display: flex;
  align-items: flex-start;
  gap: 1rem;
}

.stat-icon {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  border-radius: var(--radius-sm);
  background-color: var(--bg-main);
  border: 1px solid #e2e8f0;
  color: var(--primary);
  flex-shrink: 0;
}

.stat-card svg {
  width: 20px;
  height: 20px;
}

.stat-title {
  font-weight: 700;
  font-size: 1.1rem;
  color: var(--text-main);
  line-height: 1.3;
}

.stat-desc {
  font-size: 0.85rem;
  color: var(--text-light);
  margin-top: 0.15rem;
}

/* Common Section Styles */
.section {
  padding: 6rem 0;
}

.section-bg {
  background-color: var(--bg-sub);
}

.section-header {
  text-align: center;
  max-width: 680px;
  margin: 0 auto 3.5rem auto;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.section-label {
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  color: var(--primary);
}

.section-title {
  font-size: 2rem;
  font-weight: 800;
  letter-spacing: -0.025em;
  color: var(--text-main);
}

.section-subtitle {
  font-size: 1.05rem;
  color: var(--text-muted);
}

/* Course Features / Grid details */
.features-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 2rem;
}

.feature-card {
  background-color: var(--bg-main);
  border: 1px solid #e2e8f0;
  padding: 2.25rem;
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
  transition: var(--transition);
}

.feature-card:hover {
  transform: translateY(-4px);
  border-color: var(--border-hover);
  box-shadow: var(--shadow-md);
}

.feature-card-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 52px;
  height: 52px;
  background-color: var(--primary-light);
  color: var(--primary);
  border-radius: var(--radius-sm);
  margin-bottom: 1.5rem;
}

.feature-card-icon svg {
  width: 24px;
  height: 24px;
}

.feature-card-title {
  font-size: 1.25rem;
  font-weight: 700;
  margin-bottom: 0.75rem;
  color: var(--text-main);
}

.feature-card-desc {
  font-size: 0.95rem;
  color: var(--text-muted);
}

/* Table of Contents Section (Minimal & Compact) */
.toc-wrapper {
  max-width: 900px;
  margin: 0 auto;
}

.search-box-wrapper {
  position: relative;
  margin-bottom: 2.5rem;
}

.search-icon {
  position: absolute;
  left: 1.25rem;
  top: 50%;
  transform: translateY(-50%);
  color: var(--text-light);
  pointer-events: none;
}

.search-icon svg {
  width: 20px;
  height: 20px;
}

.search-input {
  width: 100%;
  padding: 1.1rem 1.25rem 1.1rem 3.25rem;
  font-family: inherit;
  font-size: 1rem;
  border-radius: var(--radius-md);
  border: 1px solid var(--border);
  background-color: var(--bg-main);
  outline: none;
  transition: var(--transition);
  box-shadow: var(--shadow-sm);
}

.search-input:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 4px rgba(37, 96, 255, 0.15);
}

.modules-list {
  display: flex;
  flex-direction: column;
  gap: 2rem;
}

.module-card {
  background-color: var(--bg-main);
  border: 1px solid #cbd5e1;
  border-radius: var(--radius-md);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
}

.module-header {
  padding: 1.25rem 1.5rem;
  background-color: var(--bg-sub);
  border-bottom: 1px solid #cbd5e1;
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
}

.module-num {
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  color: var(--primary);
  letter-spacing: 0.05em;
}

.module-name {
  font-size: 1.2rem;
  font-weight: 800;
  color: var(--text-main);
  letter-spacing: -0.02em;
}

/* Minimal Topics List (No link wrapper, 2 columns on desktop) */
.topics-list {
  padding: 1.25rem 1.5rem;
  display: grid;
  grid-template-columns: 1fr;
  gap: 0.75rem;
}

.topic-item {
  display: flex;
  align-items: center;
  gap: 1rem;
  font-size: 0.95rem;
  color: var(--text-main);
}

.topic-index {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 26px;
  height: 26px;
  background-color: var(--primary-light);
  color: var(--primary);
  font-size: 0.8rem;
  font-weight: 700;
  border-radius: 50%;
  flex-shrink: 0;
}

.topic-title {
  font-weight: 600;
  color: var(--text-muted);
}

/* Empty State Search */
.no-results {
  text-align: center;
  padding: 3rem;
  background-color: var(--bg-sub);
  border: 1px dashed var(--border);
  border-radius: var(--radius-md);
  display: none;
}

.no-results-icon {
  margin: 0 auto 1rem auto;
  color: var(--text-light);
}

.no-results-icon svg {
  width: 48px;
  height: 48px;
}

.no-results-title {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--text-main);
}

.no-results-desc {
  font-size: 0.9rem;
  color: var(--text-muted);
  margin-top: 0.25rem;
}

/* Compare / Support Options Section */
.comparison-section {
  background-color: var(--bg-main);
}

.comparison-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 2.5rem;
  align-items: stretch;
  max-width: 960px;
  margin: 0 auto;
}

.pricing-card {
  background-color: var(--bg-main);
  border: 2px solid #cbd5e1;
  border-radius: var(--radius-lg);
  padding: 2.5rem;
  display: flex;
  flex-direction: column;
  position: relative;
  transition: var(--transition);
}

.pricing-card.featured {
  border-color: var(--primary);
  box-shadow: var(--shadow-lg);
}

.pricing-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}

.pricing-card-badge {
  position: absolute;
  top: -14px;
  left: 50%;
  transform: translateX(-50%);
  background-color: var(--primary);
  color: var(--bg-main);
  padding: 0.25rem 1rem;
  border-radius: var(--radius-pill);
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.05em;
  text-transform: uppercase;
}

.pricing-card-header {
  margin-bottom: 2rem;
  text-align: center;
}

.pricing-card-title {
  font-size: 1.5rem;
  font-weight: 800;
  color: var(--text-main);
  margin-bottom: 0.5rem;
}

.pricing-card-price {
  font-size: 3rem;
  font-weight: 800;
  color: var(--text-main);
  line-height: 1;
}

.pricing-card-price span {
  font-size: 1rem;
  font-weight: 500;
  color: var(--text-muted);
}

.pricing-card-features {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  margin-bottom: 2.5rem;
  flex-grow: 1;
}

.pricing-feature-item {
  display: flex;
  align-items: flex-start;
  gap: 0.75rem;
  font-size: 0.95rem;
}

.pricing-feature-icon {
  color: var(--primary);
  flex-shrink: 0;
  margin-top: 0.1rem;
}

.pricing-card.featured .pricing-feature-icon {
  color: var(--success);
}

.pricing-feature-icon svg {
  width: 18px;
  height: 18px;
}

.pricing-feature-text {
  color: var(--text-muted);
}

.pricing-card-ctas {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

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

/* Bordered & highlighted Paypal / Github buttons */
.payment-options-row {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 1rem;
  margin-top: 1rem;
  flex-wrap: wrap;
}

.payment-option-link {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--text-main);
  border: 2px solid var(--primary);
  background-color: var(--bg-main);
  padding: 0.5rem 1rem;
  border-radius: var(--radius-sm);
  transition: var(--transition);
  box-shadow: var(--shadow-sm);
}

.payment-option-link:hover {
  background-color: var(--primary-light);
  color: var(--primary);
  transform: translateY(-1px);
}

.payment-option-link svg {
  width: 14px;
  height: 14px;
}

/* Transparency Callout (Pledge) */
.transparency-callout {
  margin: 4rem auto 0 auto;
  max-width: 780px;
  background-color: var(--primary-light);
  border: 1px solid rgba(37, 96, 255, 0.15);
  border-radius: var(--radius-md);
  padding: 2rem;
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  gap: 0.75rem;
}

.transparency-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  background-color: var(--bg-main);
  color: var(--primary);
  border: 1px solid rgba(37, 96, 255, 0.15);
  padding: 0.25rem 0.75rem;
  border-radius: var(--radius-pill);
  font-size: 0.75rem;
  font-weight: 800;
  letter-spacing: 0.025em;
  text-transform: uppercase;
}

.transparency-title {
  font-size: 1.15rem;
  font-weight: 800;
  color: var(--primary);
  letter-spacing: -0.02em;
}

.transparency-desc {
  font-size: 0.95rem;
  color: var(--text-muted);
  max-width: 620px;
  line-height: 1.5;
}

/* Footer styling */
footer {
  background-color: var(--bg-sub);
  border-top: 1px solid #e2e8f0;
  padding: 4rem 0 2rem 0;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 3rem;
  margin-bottom: 3rem;
}

.footer-about {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.footer-about-logo {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.footer-about-title {
  font-weight: 800;
  font-size: 1.1rem;
  letter-spacing: -0.02em;
}

.footer-about-text {
  font-size: 0.9rem;
  color: var(--text-muted);
  max-width: 340px;
}

.footer-credits {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.footer-credits-title {
  font-weight: 700;
  font-size: 0.9rem;
  text-transform: uppercase;
  color: var(--text-light);
  letter-spacing: 0.05em;
}

.footer-credits-text {
  font-size: 0.9rem;
  color: var(--text-muted);
  line-height: 1.5;
}

.footer-credits-text a {
  color: var(--text-main);
  font-weight: 600;
  border-bottom: 1.5px solid #cbd5e1;
}

.footer-credits-text a:hover {
  color: var(--primary);
  border-color: var(--primary);
}

.footer-bottom {
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  align-items: center;
  gap: 1.5rem;
  border-top: 1px solid #e2e8f0;
  padding-top: 2rem;
}

.footer-copy {
  font-size: 0.85rem;
  color: var(--text-light);
  text-align: center;
}

.footer-links {
  display: flex;
  gap: 1.5rem;
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text-light);
}

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

/* Media Queries for Desktop Grid Layouts & Responsiveness */
@media (max-width: 767px) {
  .hero-content {
    text-align: center;
    align-items: center;
  }
  
  .hero-badge {
    align-self: center;
  }
  
  .hero-ctas {
    justify-content: center;
  }
  
  .hero-ctas .btn {
    width: 100%;
  }

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

@media (min-width: 768px) {
  .hero-section {
    padding-top: 5rem;
    padding-bottom: 6rem;
  }
  
  .hero-grid {
    grid-template-columns: 1fr 1.1fr;
    gap: 4rem;
  }
  
  .hero-title {
    font-size: 2.5rem;
  }
  
  .section-title {
    font-size: 2.5rem;
  }
  
  .features-grid {
    grid-template-columns: repeat(3, 1fr);
  }

  /* Split topics list into 2 columns on larger screens */
  .topics-list {
    grid-template-columns: repeat(2, 1fr);
    gap: 0.75rem 2rem;
  }
  
  .comparison-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  
  .footer-grid {
    grid-template-columns: 1.5fr 1fr;
    gap: 6rem;
  }
  
  .footer-bottom {
    flex-direction: row;
  }
}