@import url('https://fonts.googleapis.com/css2?family=Space+Grotesk:wght@400;600;700&family=IBM+Plex+Mono:wght@600&display=swap');

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

:root {
  --black: #0A0A0A;
  --white: #FFFFFF;
  --gray-50: #FAFAFA;
  --gray-100: #F5F5F5;
  --gray-200: #E5E5E5;
  --gray-300: #D4D4D4;
  --gray-400: #A3A3A3;
  --gray-600: #525252;
  --gray-800: #262626;
  --accent: #0066FF;
  --accent-dark: #0052CC;
  --accent-light: #3385FF;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: 'Space Grotesk', sans-serif;
  background: var(--white);
  color: var(--black);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 40px;
}

/* ===== NAVIGATION ===== */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  background: var(--white);
  border-bottom: 1px solid var(--gray-200);
  z-index: 1000;
  padding: 0;
}

.nav-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 40px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: 70px;
}

.nav-logo {
  display: flex;
  flex-direction: column;
}

.logo-title {
  font-size: 14px;
  font-weight: 700;
  line-height: 1;
  color: var(--black);
}

.logo-subtitle {
  font-size: 10px;
  color: var(--gray-600);
  font-weight: 500;
  margin-top: 2px;
}

.nav-links {
  display: flex;
  gap: 32px;
  align-items: center;
}

.nav-links a {
  text-decoration: none;
  color: var(--black);
  font-size: 14px;
  font-weight: 500;
  transition: color 0.2s;
}

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

.nav-cta {
  background: var(--black);
  color: var(--white) !important;
  padding: 10px 20px;
  border-radius: 4px;
  font-weight: 600;
  transition: background 0.2s;
}

.nav-cta:hover {
  background: var(--accent);
  color: var(--white) !important;
}

/* ===== HERO SECTION ===== */
.hero {
  background: var(--white);
  padding-top: 70px;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

.hero-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 40px;
  display: flex;
  flex-direction: column;
  flex: 1;
}

.hero-content {
  flex: 1;
  padding: 100px 0 60px 0;
  display: flex;
  flex-direction: column;
  justify-content: center;
}

.hero-title {
  font-size: 64px;
  font-weight: 700;
  line-height: 0.95;
  margin-bottom: 24px;
  letter-spacing: -2px;
}

.highlight {
  color: var(--accent);
  display: block;
}

.hero-subtitle {
  font-size: 24px;
  font-weight: 400;
  color: var(--gray-600);
  max-width: 600px;
  margin-bottom: 48px;
  line-height: 1.4;
}

.hero-author {
  border-top: 4px solid var(--black);
  padding-top: 24px;
  margin-bottom: 32px;
}

.hero-author .author-name {
  font-size: 28px;
  font-weight: 700;
  margin-bottom: 8px;
}

.hero-author .author-role {
  font-size: 14px;
  color: var(--gray-600);
  font-weight: 500;
}

.hero-meta {
  display: flex;
  gap: 48px;
  margin-bottom: 40px;
}

.meta-item {
  display: flex;
  flex-direction: column;
}

.meta-label {
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 2px;
  color: var(--gray-400);
  margin-bottom: 4px;
}

.meta-value {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 18px;
  font-weight: 600;
  color: var(--black);
}

.hero-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background: var(--accent);
  color: var(--white);
  padding: 16px 40px;
  font-size: 16px;
  font-weight: 600;
  text-decoration: none;
  border-radius: 4px;
  transition: all 0.2s;
  align-self: flex-start;
}

.hero-btn:hover {
  background: var(--accent-dark);
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(0, 102, 255, 0.3);
}

.hero-stats {
  background: var(--black);
  color: var(--white);
  padding: 32px;
  display: flex;
  justify-content: space-around;
  gap: 48px;
}

.stat {
  display: flex;
  flex-direction: column;
  align-items: center;
}

.stat-number {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 48px;
  font-weight: 700;
  line-height: 1;
  margin-bottom: 8px;
}

.stat-label {
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 2px;
  opacity: 0.7;
}

/* ===== SECTIONS ===== */
section {
  padding: 120px 0;
}

.section-title {
  font-size: 48px;
  font-weight: 700;
  margin-bottom: 16px;
  letter-spacing: -1px;
}

.section-subtitle {
  font-size: 18px;
  color: var(--gray-600);
  margin-bottom: 60px;
  font-weight: 400;
}

/* ===== INSIDE SECTION ===== */
.inside {
  background: var(--gray-50);
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 32px;
}

.feature-card {
  background: var(--white);
  padding: 32px;
  border: 1px solid var(--gray-200);
  transition: all 0.3s;
}

.feature-card:hover {
  border-color: var(--accent);
  transform: translateY(-4px);
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.08);
}

.feature-number {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 14px;
  font-weight: 600;
  color: var(--accent);
  margin-bottom: 16px;
}

.feature-card h3 {
  font-size: 24px;
  font-weight: 700;
  margin-bottom: 12px;
  line-height: 1.2;
}

.feature-card p {
  font-size: 15px;
  color: var(--gray-600);
  line-height: 1.6;
}

/* ===== CHAPTERS SECTION ===== */
.intro-box {
  background: var(--white);
  padding: 32px;
  border: 2px solid var(--black);
  margin-bottom: 40px;
}

.intro-box h3 {
  font-size: 20px;
  font-weight: 700;
  margin-bottom: 12px;
}

.intro-box p {
  font-size: 14px;
  color: var(--gray-600);
  line-height: 1.6;
}

.chapter-sections {
  display: flex;
  flex-direction: column;
  gap: 48px;
}

.chapter-section {
  background: var(--gray-50);
  padding: 40px;
  border-left: 4px solid var(--accent);
}

.section-header {
  margin-bottom: 24px;
}

.section-badge {
  display: inline-block;
  background: var(--black);
  color: var(--white);
  padding: 6px 12px;
  font-size: 11px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 2px;
  margin-bottom: 12px;
}

.section-header h3 {
  font-size: 24px;
  font-weight: 700;
  line-height: 1.2;
}

.chapter-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
}

.chapter-item {
  background: var(--white);
  padding: 20px;
  border-left: 3px solid var(--accent);
  display: flex;
  flex-direction: column;
  gap: 8px;
  transition: all 0.2s;
}

.chapter-item:hover {
  transform: translateX(4px);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
}

.ch-num {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 11px;
  font-weight: 600;
  color: var(--accent);
}

.ch-title {
  font-size: 18px;
  font-weight: 700;
  line-height: 1.2;
  color: var(--black);
}

.ch-desc {
  font-size: 13px;
  color: var(--gray-600);
  line-height: 1.5;
}

/* ===== CASES SECTION ===== */
.cases {
  background: var(--black);
  color: var(--white);
}

.cases .section-title {
  color: var(--white);
}

.cases .section-subtitle {
  color: var(--gray-400);
}

.cases-section {
  margin-bottom: 80px;
}

.cases-section:last-child {
  margin-bottom: 0;
}

.cases-section-title {
  font-size: 20px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 2px;
  color: var(--accent);
  margin-bottom: 40px;
  padding-bottom: 12px;
  border-bottom: 2px solid var(--gray-800);
}

/* Chapter Case Groups */
.chapter-case-group {
  margin-bottom: 48px;
  background: rgba(255, 255, 255, 0.02);
  padding: 32px;
  border-left: 4px solid var(--accent);
}

.chapter-case-header {
  display: flex;
  align-items: center;
  gap: 16px;
  margin-bottom: 12px;
}

.chapter-number {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 12px;
  font-weight: 700;
  color: var(--accent);
  background: rgba(0, 102, 255, 0.15);
  padding: 6px 12px;
  border-radius: 4px;
  text-transform: uppercase;
  letter-spacing: 1px;
}

.chapter-case-title {
  font-size: 20px;
  font-weight: 700;
  color: var(--white);
  line-height: 1.3;
}

.chapter-question {
  font-size: 15px;
  font-style: italic;
  color: var(--gray-400);
  margin-bottom: 24px;
  padding-left: 4px;
}

/* Cases Grid */
.cases-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.case-item {
  background: rgba(255, 255, 255, 0.03);
  padding: 20px;
  border-left: 3px solid var(--accent);
  transition: all 0.2s;
}

.case-item:hover {
  background: rgba(255, 255, 255, 0.06);
  transform: translateX(4px);
}

.case-header {
  display: flex;
  align-items: baseline;
  gap: 12px;
  margin-bottom: 12px;
}

.case-num {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 12px;
  font-weight: 600;
  color: var(--accent);
  flex-shrink: 0;
}

.case-name {
  font-size: 16px;
  font-weight: 700;
  line-height: 1.3;
  color: var(--white);
}

.case-desc {
  font-size: 13px;
  line-height: 1.6;
  color: var(--gray-400);
}

/* Grand Finale Box */
.grand-finale-box {
  margin-top: 60px;
  padding: 40px;
  background: var(--accent);
  border-radius: 8px;
  text-align: center;
}

.grand-finale-title {
  color: var(--white);
  font-size: 32px;
  font-weight: 700;
  margin-bottom: 16px;
  letter-spacing: -1px;
}

.grand-finale-text {
  color: rgba(255,255,255,0.95);
  font-size: 18px;
  line-height: 1.7;
  max-width: 800px;
  margin: 0 auto;
}

/* ===== AUTHOR SECTION ===== */
.author {
  background: var(--gray-50);
}

.author-bio-grid {
  display: grid;
  grid-template-columns: 350px 1fr;
  gap: 60px;
  align-items: start;
}

.author-image-wrapper {
  position: sticky;
  top: 100px;
}

.author-photo {
  width: 100%;
  height: auto;
  border-radius: 4px;
  margin-bottom: 16px;
  border: 4px solid var(--black);
}

.author-image-caption {
  font-size: 14px;
  font-weight: 600;
  text-align: center;
  color: var(--gray-600);
}

.author-header-info {
  margin-bottom: 32px;
}

.author-main-name {
  font-size: 48px;
  font-weight: 700;
  line-height: 1.1;
  margin-bottom: 12px;
  letter-spacing: -1px;
}

.author-credentials {
  font-size: 18px;
  color: var(--gray-600);
  font-weight: 600;
  margin-bottom: 8px;
}

.author-title {
  font-size: 16px;
  color: var(--black);
  font-weight: 600;
}

.author-highlights {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  padding: 32px;
  background: var(--white);
  border: 1px solid var(--gray-200);
  margin-bottom: 32px;
}

.highlight-stat {
  text-align: center;
}

.highlight-num {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 36px;
  font-weight: 700;
  color: var(--accent);
  line-height: 1;
  margin-bottom: 8px;
}

.highlight-text {
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 1px;
  color: var(--gray-600);
}

.author-bio-text {
  margin-bottom: 32px;
}

.author-bio-text p {
  font-size: 15px;
  line-height: 1.8;
  color: var(--gray-600);
  margin-bottom: 20px;
}

.author-bio-text strong {
  color: var(--black);
  font-weight: 600;
}

.author-links {
  display: flex;
  gap: 24px;
  flex-wrap: wrap;
}

.author-link {
  color: var(--accent);
  text-decoration: none;
  font-size: 14px;
  font-weight: 600;
  transition: color 0.2s;
}

.author-link:hover {
  color: var(--accent-dark);
  text-decoration: underline;
}

/* ===== SIGNUP SECTION ===== */
.signup {
  background: var(--accent);
  color: var(--white);
  padding: 100px 0;
}

.signup-container {
  max-width: 700px;
  margin: 0 auto;
  padding: 0 40px;
}

.signup-title {
  font-size: 42px;
  font-weight: 700;
  line-height: 1.2;
  margin-bottom: 16px;
  text-align: center;
}

.signup-subtitle {
  font-size: 18px;
  line-height: 1.6;
  margin-bottom: 48px;
  text-align: center;
  opacity: 0.9;
}

.signup-button {
  display: inline-block;
  width: 100%;
  max-width: 400px;
  padding: 20px 48px;
  font-size: 18px;
  font-weight: 700;
  font-family: 'Space Grotesk', sans-serif;
  background: var(--black);
  color: var(--white);
  text-decoration: none;
  border-radius: 8px;
  cursor: pointer;
  transition: all 0.3s;
  text-transform: uppercase;
  letter-spacing: 2px;
  text-align: center;
  margin: 0 auto;
  display: block;
}

.signup-button:hover {
  background: var(--white);
  color: var(--accent);
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.3);
}

.signup-form {
  background: var(--white);
  padding: 48px;
  border-radius: 8px;
}

.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}

.form-group {
  margin-bottom: 16px;
}

.form-group input,
.form-group select {
  width: 100%;
  padding: 14px 16px;
  font-size: 15px;
  font-family: 'Space Grotesk', sans-serif;
  border: 2px solid var(--gray-200);
  border-radius: 4px;
  transition: all 0.2s;
  background: var(--white);
}

.form-group input:focus,
.form-group select:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(0, 102, 255, 0.1);
}

.checkbox-group {
  margin-top: 8px;
}

.checkbox-label {
  display: flex;
  align-items: start;
  gap: 12px;
  font-size: 13px;
  color: var(--gray-600);
  cursor: pointer;
}

.checkbox-label input[type="checkbox"] {
  width: auto;
  margin-top: 2px;
  cursor: pointer;
}

.submit-btn {
  width: 100%;
  padding: 16px;
  font-size: 16px;
  font-weight: 700;
  font-family: 'Space Grotesk', sans-serif;
  background: var(--black);
  color: var(--white);
  border: none;
  border-radius: 4px;
  cursor: pointer;
  transition: all 0.2s;
  text-transform: uppercase;
  letter-spacing: 1px;
  margin-top: 8px;
}

.submit-btn:hover {
  background: var(--accent);
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.2);
}

.signup-note {
  text-align: center;
  font-size: 13px;
  margin-top: 24px;
  opacity: 0.8;
}

/* ===== FOOTER ===== */
.footer {
  background: var(--black);
  color: var(--white);
  padding: 80px 0 40px 0;
}

.footer-content {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 60px;
  margin-bottom: 60px;
}

.footer-col h4 {
  font-size: 14px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 2px;
  margin-bottom: 16px;
}

.footer-col p {
  font-size: 14px;
  line-height: 1.8;
  opacity: 0.8;
}

.footer-col a {
  color: var(--white);
  text-decoration: none;
  transition: color 0.2s;
}

.footer-col a:hover {
  color: var(--accent);
}

.footer-bottom {
  padding-top: 40px;
  border-top: 1px solid var(--gray-800);
}

.footer-disclaimer {
  font-size: 11px;
  line-height: 1.6;
  opacity: 0.6;
  margin-bottom: 16px;
}

.footer-copyright {
  font-size: 12px;
  opacity: 0.6;
}

/* ===== RESPONSIVE DESIGN ===== */
@media (max-width: 1024px) {
  .container,
  .nav-container,
  .hero-container {
    padding: 0 32px;
  }
  
  .features-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  
  .chapter-grid {
    grid-template-columns: 1fr;
  }
  
  .cases-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  
  .author-bio-grid {
    grid-template-columns: 1fr;
    gap: 40px;
  }
  
  .author-image-wrapper {
    position: relative;
    top: 0;
    max-width: 350px;
    margin: 0 auto;
  }
}

@media (max-width: 768px) {
  .nav-links {
    display: none;
  }
  
  .hero-title {
    font-size: 42px;
  }
  
  .hero-subtitle {
    font-size: 18px;
  }
  
  .section-title {
    font-size: 36px;
  }
  
  .features-grid {
    grid-template-columns: 1fr;
  }
  
  .chapter-section {
    padding: 24px;
  }
  
  .cases-grid {
    grid-template-columns: 1fr;
  }
  
  .chapter-case-group {
    padding: 24px;
  }
  
  .form-row {
    grid-template-columns: 1fr;
  }
  
  .footer-content {
    grid-template-columns: 1fr;
    gap: 40px;
  }
  
  .hero-stats {
    flex-direction: column;
    gap: 32px;
  }
  
  .author-highlights {
    grid-template-columns: 1fr;
  }
  
  .signup-form {
    padding: 32px 24px;
  }
}

@media (max-width: 480px) {
  .hero-title {
    font-size: 32px;
  }
  
  .section-title {
    font-size: 28px;
  }
  
  .container,
  .nav-container,
  .hero-container {
    padding: 0 20px;
  }
  
  section {
    padding: 80px 0;
  }
}