/* ============================================
   The Prompt Engineering Playbook — Landing Page
   Dark theme with emerald-cyan accent gradient
   ============================================ */

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

:root {
  --bg: #0a0f0a;
  --bg-card: #111a14;
  --border-card: #1e2e22;
  --text: #e0e8e2;
  --text-muted: #88a090;
  --accent-start: #10b981;
  --accent-end: #06b6d4;
  --accent-gradient: linear-gradient(135deg, var(--accent-start), var(--accent-end));
  --glow-color: rgba(16, 185, 129, 0.3);
  --radius: 12px;
  --radius-sm: 8px;
  --transition: 0.3s ease;
}

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

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.7;
  font-size: 1.1rem;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

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

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

a:hover {
  color: var(--accent-end);
}

/* --- Utility --- */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 1.5rem;
}

.section-heading {
  font-size: 2rem;
  font-weight: 700;
  text-align: center;
  margin-bottom: 3rem;
  letter-spacing: -0.02em;
}

/* --- CTA Button --- */
.cta-button {
  display: inline-block;
  padding: 1rem 2.5rem;
  font-size: 1.15rem;
  font-weight: 700;
  font-family: inherit;
  color: #fff;
  background: var(--accent-gradient);
  border: none;
  border-radius: 50px;
  cursor: pointer;
  box-shadow: 0 4px 24px var(--glow-color);
  transition: transform var(--transition), box-shadow var(--transition);
  letter-spacing: 0.01em;
}

.cta-button:hover {
  transform: scale(1.045);
  box-shadow: 0 6px 36px rgba(16, 185, 129, 0.5);
}

.cta-button:active {
  transform: scale(0.98);
}

.cta-button-lg {
  padding: 1.2rem 3rem;
  font-size: 1.3rem;
}

/* ============================================
   HERO
   ============================================ */
.hero {
  padding: 6rem 0 5rem;
  min-height: 90vh;
  display: flex;
  align-items: center;
  background:
    radial-gradient(ellipse 80% 60% at 50% -10%, rgba(16, 185, 129, 0.1), transparent),
    radial-gradient(ellipse 60% 50% at 80% 50%, rgba(6, 182, 212, 0.07), transparent),
    var(--bg);
}

.hero-inner {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 4rem;
  align-items: center;
}

.hero-content {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
}

.hero-headline {
  font-size: 3.5rem;
  font-weight: 800;
  line-height: 1.1;
  letter-spacing: -0.03em;
  margin-bottom: 1.5rem;
  background: linear-gradient(135deg, #ffffff 0%, #a7f3d0 50%, #06b6d4 100%);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-subheadline {
  font-size: 1.25rem;
  color: var(--text-muted);
  margin-bottom: 2.5rem;
  max-width: 520px;
  line-height: 1.7;
}

/* --- 3D Book Mockup --- */
.hero-book {
  display: flex;
  justify-content: center;
  align-items: center;
  perspective: 1200px;
}

.book-mockup {
  position: relative;
  width: 280px;
  height: 380px;
  transform-style: preserve-3d;
  transform: rotateY(-25deg) rotateX(5deg);
  transition: transform 0.6s ease;
}

.book-mockup:hover {
  transform: rotateY(-15deg) rotateX(2deg);
}

.book-cover {
  position: absolute;
  inset: 0;
  background: var(--accent-gradient);
  border-radius: 4px 12px 12px 4px;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow:
    6px 6px 30px rgba(0, 0, 0, 0.5),
    inset 0 0 60px rgba(255, 255, 255, 0.06);
  transform: translateZ(20px);
}

.book-cover-content {
  text-align: center;
  padding: 2rem;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.book-label {
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 0.25em;
  color: rgba(255, 255, 255, 0.7);
}

.book-title {
  font-size: 1.4rem;
  font-weight: 800;
  color: #fff;
  line-height: 1.2;
}

.book-subtitle {
  font-size: 0.75rem;
  color: rgba(255, 255, 255, 0.65);
  margin-top: 0.5rem;
}

.book-spine {
  position: absolute;
  top: 0;
  left: 0;
  width: 40px;
  height: 100%;
  background: linear-gradient(135deg, #0d9668, #0891b2);
  border-radius: 4px 0 0 4px;
  transform: rotateY(90deg) translateZ(0px) translateX(-20px);
  transform-origin: left center;
}

.book-shadow {
  position: absolute;
  bottom: -30px;
  left: 10%;
  width: 80%;
  height: 30px;
  background: radial-gradient(ellipse, rgba(16, 185, 129, 0.2), transparent 70%);
  filter: blur(12px);
  transform: translateZ(-10px);
}

/* ============================================
   PAIN POINTS
   ============================================ */
.pain-points {
  padding: 6rem 0;
}

.pain-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1.5rem;
}

.pain-card {
  background: var(--bg-card);
  border: 1px solid var(--border-card);
  border-radius: var(--radius);
  padding: 2rem;
  display: flex;
  gap: 1.25rem;
  align-items: flex-start;
  transition: border-color var(--transition), transform var(--transition);
}

.pain-card:hover {
  border-color: var(--accent-start);
  transform: translateY(-2px);
}

.pain-icon {
  font-size: 1.6rem;
  flex-shrink: 0;
  width: 48px;
  height: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(135deg, rgba(16, 185, 129, 0.15), rgba(6, 182, 212, 0.15));
  border-radius: 10px;
  color: var(--accent-start);
}

.pain-card p {
  color: var(--text-muted);
  font-size: 1.05rem;
}

/* ============================================
   WHAT'S INSIDE — CATEGORY CARDS
   ============================================ */
.whats-inside {
  padding: 6rem 0;
  background:
    radial-gradient(ellipse 70% 40% at 20% 80%, rgba(16, 185, 129, 0.06), transparent),
    var(--bg);
}

.category-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
}

.category-card {
  background: var(--bg-card);
  border: 1px solid var(--border-card);
  border-radius: var(--radius);
  padding: 2rem;
  transition: border-color var(--transition), transform var(--transition);
}

.category-card:hover {
  border-color: var(--accent-end);
  transform: translateY(-3px);
}

.category-name {
  font-size: 1.15rem;
  font-weight: 700;
  margin-bottom: 1.25rem;
  background: var(--accent-gradient);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

.prompt-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.prompt-list li {
  padding-left: 1.25rem;
  position: relative;
  color: var(--text-muted);
  font-size: 0.95rem;
}

.prompt-list li::before {
  content: "\2022";
  position: absolute;
  left: 0;
  color: var(--accent-start);
  font-weight: 700;
}

/* ============================================
   SAMPLE PROMPT
   ============================================ */
.sample-prompt {
  padding: 6rem 0;
}

.sample-card {
  background: var(--bg-card);
  border: 1px solid var(--border-card);
  border-radius: var(--radius);
  padding: 3rem;
  max-width: 900px;
  margin: 0 auto;
  position: relative;
  overflow: hidden;
}

.sample-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: var(--accent-gradient);
}

.sample-header {
  margin-bottom: 2rem;
}

.sample-category-tag {
  display: inline-block;
  padding: 0.3rem 0.9rem;
  font-size: 0.8rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  background: linear-gradient(135deg, rgba(16, 185, 129, 0.15), rgba(6, 182, 212, 0.15));
  color: var(--accent-start);
  border-radius: 50px;
  margin-bottom: 0.75rem;
}

.sample-title {
  font-size: 1.5rem;
  font-weight: 700;
}

.sample-description {
  color: var(--text-muted);
  margin-bottom: 2rem;
  font-size: 1.05rem;
}

.prompt-template {
  background: #0f1a12;
  border: 1px solid #1e3025;
  border-radius: var(--radius-sm);
  padding: 1.5rem;
  margin-bottom: 2rem;
  font-family: 'JetBrains Mono', 'Fira Code', monospace;
  font-size: 0.9rem;
  line-height: 1.7;
  color: #a7f3d0;
  white-space: pre-wrap;
}

.prompt-template .placeholder {
  color: var(--accent-end);
  font-weight: 600;
}

.sample-tips h4 {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: 1rem;
}

.sample-tips ul {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.sample-tips ul li {
  padding-left: 1.25rem;
  position: relative;
  color: var(--text-muted);
  font-size: 0.95rem;
}

.sample-tips ul li::before {
  content: "\2713";
  position: absolute;
  left: 0;
  color: #22c55e;
  font-weight: 700;
}

/* ============================================
   SOCIAL PROOF / TESTIMONIALS
   ============================================ */
.social-proof {
  padding: 6rem 0;
  background:
    radial-gradient(ellipse 60% 40% at 80% 20%, rgba(6, 182, 212, 0.06), transparent),
    var(--bg);
}

.testimonials-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
}

.testimonial-card {
  background: var(--bg-card);
  border: 1px solid var(--border-card);
  border-radius: var(--radius);
  padding: 2rem;
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
  transition: border-color var(--transition), transform var(--transition);
}

.testimonial-card:hover {
  border-color: var(--accent-end);
  transform: translateY(-3px);
}

.testimonial-avatar {
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: var(--accent-gradient);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 0.9rem;
  color: #fff;
  flex-shrink: 0;
}

.testimonial-quote {
  color: var(--text);
  font-size: 1rem;
  line-height: 1.7;
  font-style: normal;
  border: none;
}

.testimonial-cite {
  font-style: normal;
  font-size: 0.9rem;
  color: var(--text-muted);
}

/* ============================================
   FINAL CTA
   ============================================ */
.final-cta {
  padding: 6rem 0;
  text-align: center;
  background:
    radial-gradient(ellipse 80% 50% at 50% 100%, rgba(16, 185, 129, 0.08), transparent),
    var(--bg);
}

.final-cta-inner {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1.25rem;
}

.price-tag {
  font-size: 3.5rem;
  font-weight: 800;
  background: var(--accent-gradient);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

.cta-subtext {
  color: var(--text-muted);
  font-size: 1.1rem;
  margin-bottom: 0.5rem;
}

.guarantee-text {
  color: var(--text-muted);
  font-size: 0.9rem;
  margin-top: 0.5rem;
}

/* ============================================
   FAQ ACCORDION
   ============================================ */
.faq {
  padding: 6rem 0;
}

.faq-list {
  max-width: 780px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.faq-item {
  background: var(--bg-card);
  border: 1px solid var(--border-card);
  border-radius: var(--radius-sm);
  overflow: hidden;
  transition: border-color var(--transition);
}

.faq-item.is-open {
  border-color: var(--accent-start);
}

.faq-question {
  width: 100%;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1.25rem 1.5rem;
  font-family: inherit;
  font-size: 1.05rem;
  font-weight: 600;
  color: var(--text);
  background: none;
  border: none;
  cursor: pointer;
  text-align: left;
  gap: 1rem;
  transition: color var(--transition);
}

.faq-question:hover {
  color: var(--accent-start);
}

.faq-icon {
  font-size: 1.4rem;
  font-weight: 300;
  color: var(--text-muted);
  transition: transform var(--transition);
  flex-shrink: 0;
  line-height: 1;
}

.faq-item.is-open .faq-icon {
  transform: rotate(45deg);
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.4s ease;
}

.faq-answer p {
  padding: 0 1.5rem 1.25rem;
  color: var(--text-muted);
  font-size: 0.95rem;
  line-height: 1.7;
}

/* ============================================
   FOOTER
   ============================================ */
.site-footer {
  padding: 3rem 0;
  border-top: 1px solid var(--border-card);
}

.footer-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 1rem;
}

.copyright {
  color: var(--text-muted);
  font-size: 0.9rem;
}

.footer-links {
  display: flex;
  gap: 2rem;
}

.footer-links a {
  color: var(--text-muted);
  font-size: 0.9rem;
  transition: color var(--transition);
}

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

/* ============================================
   RESPONSIVE — Tablet (<=1024px)
   ============================================ */
@media (max-width: 1024px) {
  .hero-inner {
    gap: 3rem;
  }

  .hero-headline {
    font-size: 2.8rem;
  }

  .category-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

/* ============================================
   RESPONSIVE — Mobile (<=768px)
   ============================================ */
@media (max-width: 768px) {
  .hero {
    padding: 4rem 0 3rem;
    min-height: auto;
  }

  .hero-inner {
    grid-template-columns: 1fr;
    text-align: center;
  }

  .hero-content {
    align-items: center;
  }

  .hero-subheadline {
    margin-left: auto;
    margin-right: auto;
  }

  .hero-headline {
    font-size: 2.2rem;
  }

  .hero-book {
    order: -1;
  }

  .book-mockup {
    width: 200px;
    height: 270px;
  }

  .section-heading {
    font-size: 1.6rem;
    margin-bottom: 2rem;
  }

  .pain-grid {
    grid-template-columns: 1fr;
  }

  .category-grid {
    grid-template-columns: 1fr;
  }

  .testimonials-grid {
    grid-template-columns: 1fr;
  }

  .sample-card {
    padding: 2rem 1.5rem;
  }

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

  .cta-button {
    width: 100%;
    text-align: center;
  }

  .cta-button-lg {
    width: auto;
    max-width: 100%;
  }

  .price-tag {
    font-size: 2.5rem;
  }
}