/* Extend the existing Tailwind theme without changing the site's visual identity. */
:root {
  color-scheme: dark;
  --accent: #f36425;
}
html {
  scroll-behavior: smooth;
  scroll-padding-top: 7rem;
}
body {
  margin: 0;
  color: #d4d4d4;
  background: #171717;
  font-family: Inter, sans-serif;
}
*,
*::before,
*::after {
  box-sizing: border-box;
}
section {
  scroll-margin-top: 1rem;
}
a,
button,
input,
select,
textarea {
  -webkit-tap-highlight-color: transparent;
}
a:focus-visible,
button:focus-visible,
input:focus-visible,
select:focus-visible,
textarea:focus-visible,
summary:focus-visible {
  outline: 3px solid #fb923c !important;
  outline-offset: 4px;
}
[hidden] {
  display: none !important;
}
.skip-link {
  position: fixed;
  top: -100px;
  left: 1rem;
  z-index: 100;
  background: #f36425;
  color: #171717;
  padding: 0.75rem 1rem;
  border-radius: 0.5rem;
}
.skip-link:focus {
  top: 1rem;
}
header nav {
  gap: 1rem;
  padding-top: 0.65rem;
  padding-bottom: 0.65rem;
}
.primary-navigation {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem 1.2rem;
}
.nav-link {
  font-size: 0.875rem;
  color: white;
  padding: 0.4rem 0;
}
.nav-link:hover {
  color: var(--accent);
}
#menu-toggle {
  margin-left: auto;
}
.actions {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.65rem;
}
.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: 9999px;
  padding: 0.7rem 1.1rem;
  font-size: 0.875rem;
  font-weight: 600;
  min-height: 44px;
  text-decoration: none;
  cursor: pointer;
}
.primary {
  background: var(--accent);
  color: #171717;
  border: 1px solid var(--accent);
}
.primary:hover {
  background: #fb923c;
}
.secondary {
  background: #262626;
  border: 1px solid #525252;
  color: #fff;
}
.secondary:hover {
  border-color: var(--accent);
}
.eyebrow {
  color: #fb923c;
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.065em;
}
.card-grid,
.books-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1.5rem;
}
.content-card,
.book-card {
  border: 1px solid #404040;
  background: linear-gradient(135deg, #262626, #171717);
  border-radius: 0.75rem;
  padding: 1.5rem;
  min-width: 0;
}
.content-card h3,
.book-card h3 {
  font-size: 1.2rem;
  color: #fff;
  font-weight: 600;
  line-height: 1.45;
}
.content-card p,
.book-copy p {
  margin-top: 0.8rem;
  line-height: 1.7;
  color: #b5b5b5;
}
.content-card .eyebrow,
.book-copy .eyebrow {
  color: #fb923c;
  margin: 0 0 0.75rem;
}
.content-card .actions {
  margin-top: 1rem;
}
.book-card {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}
.book-card > img {
  width: 100%;
  height: 300px;
  object-fit: contain;
  border-radius: 0.5rem;
}
.book-copy {
  display: flex;
  flex-direction: column;
  flex: 1;
  min-width: 0;
}
.book-copy .book-subtitle {
  color: #ddd;
  line-height: 1.45;
}
.book-copy .book-byline,
.book-copy .book-isbn {
  font-size: 0.8rem;
}
.book-copy .book-isbn {
  margin-top: 0.4rem;
}
.book-copy .actions {
  padding-top: 1.25rem;
  margin-top: auto;
}
.license-badge {
  display: inline-block;
  border: 1px solid #525252;
  border-radius: 999px;
  padding: 0.15rem 0.6rem;
  color: #ddd;
  font-size: 0.75rem;
}
#book-generative-ai {
  max-width: 100%;
  flex-direction: row;
}
#book-generative-ai > img {
  width: 32%;
  height: 280px;
}
.social-links a {
  min-width: 44px;
  min-height: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
}
.contact-fields {
  display: grid;
  gap: 1rem;
}
.contact-fields label {
  display: block;
  margin-bottom: 0.5rem;
  color: #d4d4d4;
  font-size: 0.875rem;
}
.contact-fields input,
.contact-fields select,
.contact-fields textarea {
  width: 100%;
  padding: 0.8rem;
  border: 1px solid #525252;
  border-radius: 0.5rem;
  background: #262626;
  color: white;
  font: inherit;
}
.contact-fields textarea {
  resize: vertical;
}
footer .footer-license {
  display: inline-block;
  margin-top: 0.75rem;
  max-width: 36rem;
  line-height: 1.7;
}
@media (min-width: 1024px) {
  .primary-navigation {
    flex: 1;
    justify-content: flex-end;
  }
  header nav {
    flex-wrap: wrap !important;
  }
}
@media (max-width: 1023px) {
  header nav {
    flex-wrap: wrap !important;
  }
  .primary-navigation {
    width: 100%;
  }
  .primary-navigation .nav-link {
    padding: 0.6rem 0.5rem;
  }
}
@media (max-width: 639px) {
  .card-grid,
  .books-grid {
    grid-template-columns: minmax(0, 1fr);
  }
  .book-card,
  .content-card {
    padding: 1.25rem;
  }
  #book-generative-ai {
    flex-direction: column;
  }
  #book-generative-ai > img {
    width: 100%;
    height: 300px;
  }
  .social-links {
    gap: 0.75rem;
  }
  footer .border-s {
    border: 0;
    padding-left: 0;
    margin-left: 0;
  }
}
@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
  *,
  *::before,
  *::after {
    transition-duration: 0s !important;
    animation-duration: 0s !important;
  }
}

/* Decorative portrait: original photo with non-destructive grayscale and fades. */
.hero-layout {
  position: relative;
  isolation: isolate;
}
.hero-copy {
  position: relative;
  z-index: 1;
}
.hero-portrait {
  display: none;
  pointer-events: none;
}
@media (min-width: 768px) {
  .hero-copy {
    max-width: 60%;
  }
  #hero-title {
    font-size: 3rem;
  }
  .hero-portrait {
    display: block;
    position: absolute;
    z-index: 0;
    top: 4rem;
    right: -2rem;
    bottom: 2rem;
    width: 48%;
    overflow: hidden;
    opacity: 0.26;
    -webkit-mask-image: linear-gradient(
      to right,
      transparent,
      #000 22%,
      #000 80%,
      transparent
    );
    mask-image: linear-gradient(
      to right,
      transparent,
      #000 22%,
      #000 80%,
      transparent
    );
  }
  .hero-portrait img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    object-position: 54% 40%;
    filter: grayscale(100%);
    -webkit-mask-image: linear-gradient(
      to bottom,
      transparent,
      #000 12%,
      #000 72%,
      transparent
    );
    mask-image: linear-gradient(
      to bottom,
      transparent,
      #000 12%,
      #000 72%,
      transparent
    );
  }
}
@media (min-width: 1024px) {
  #hero-title {
    font-size: 3.75rem;
  }
  .hero-portrait {
    top: 3rem;
    right: -3rem;
    width: 49%;
  }
}
@media (min-width: 768px) and (max-width: 1023px) {
  .hero-portrait {
    top: 5rem;
    right: 0;
    bottom: auto;
    height: 640px;
    width: 44%;
  }
}