/* Neural Networks — premium dark theme */
:root {
  --bg: #08090b;
  --bg-elevated: #101217;
  --bg-soft: #161922;
  --bg-panel: #1a1d27;
  --line: rgba(196, 165, 116, 0.18);
  --line-strong: rgba(232, 213, 176, 0.35);
  --text: #ece7de;
  --text-muted: #9a9488;
  --accent: #c4a574;
  --accent-bright: #e8d5b0;
  --accent-deep: #8f7348;
  --danger: #c97a6a;
  --ok: #7a9e7e;
  --radius: 2px;
  --shadow: 0 24px 60px rgba(0, 0, 0, 0.45);
  --font-display: "Cormorant Garamond", Georgia, serif;
  --font-body: "Manrope", system-ui, sans-serif;
  --header-h: 4.5rem;
  --ease: cubic-bezier(0.22, 1, 0.36, 1);
  --max: 1120px;
}

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: var(--font-body);
  font-size: 1.05rem;
  line-height: 1.65;
  color: var(--text);
  background:
    radial-gradient(ellipse 80% 50% at 10% -10%, rgba(196, 165, 116, 0.08), transparent 55%),
    radial-gradient(ellipse 60% 40% at 90% 0%, rgba(80, 90, 120, 0.12), transparent 50%),
    var(--bg);
  min-height: 100vh;
}

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

a {
  color: var(--accent-bright);
  text-decoration-thickness: 1px;
  text-underline-offset: 0.2em;
  transition: color 0.25s var(--ease);
}

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

h1,
h2,
h3,
h4 {
  font-family: var(--font-display);
  font-weight: 500;
  line-height: 1.15;
  letter-spacing: 0.01em;
  margin: 0 0 0.6em;
}

h1 {
  font-size: clamp(2.6rem, 6vw, 4.4rem);
}

h2 {
  font-size: clamp(1.9rem, 3.5vw, 2.75rem);
}

h3 {
  font-size: clamp(1.35rem, 2vw, 1.65rem);
}

p {
  margin: 0 0 1rem;
  color: var(--text-muted);
}

.container {
  width: min(100% - 2.5rem, var(--max));
  margin-inline: auto;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 40;
  backdrop-filter: blur(16px);
  background: rgba(8, 9, 11, 0.82);
  border-bottom: 1px solid var(--line);
}

.site-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: var(--header-h);
  gap: 1rem;
}

.brand {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  text-decoration: none;
  color: var(--text);
}

.brand__mark {
  width: 2rem;
  height: 2rem;
}

.brand__name {
  font-family: var(--font-display);
  font-size: 1.35rem;
  letter-spacing: 0.04em;
}

.nav {
  display: flex;
  align-items: center;
  gap: 1.5rem;
}

.nav a {
  color: var(--text-muted);
  text-decoration: none;
  font-size: 0.92rem;
  letter-spacing: 0.02em;
}

.nav a:hover,
.nav a[aria-current="page"] {
  color: var(--accent-bright);
}

.nav-toggle {
  display: none;
  background: transparent;
  border: 1px solid var(--line-strong);
  color: var(--text);
  width: 2.75rem;
  height: 2.75rem;
  cursor: pointer;
}

.nav-toggle span {
  display: block;
  width: 1.1rem;
  height: 1px;
  margin: 0.28rem auto;
  background: var(--accent);
}

@media (max-width: 920px) {
  .nav-toggle {
    display: block;
  }

  .nav {
    position: absolute;
    inset: var(--header-h) 0 auto;
    flex-direction: column;
    align-items: stretch;
    padding: 1.25rem 1.25rem 1.5rem;
    background: var(--bg-elevated);
    border-bottom: 1px solid var(--line);
    display: none;
    gap: 0.85rem;
  }

  .nav.is-open {
    display: flex;
  }
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.85rem 1.4rem;
  border: 1px solid transparent;
  font-family: var(--font-body);
  font-size: 0.92rem;
  letter-spacing: 0.04em;
  text-decoration: none;
  cursor: pointer;
  transition: transform 0.35s var(--ease), background 0.35s var(--ease),
    border-color 0.35s var(--ease), color 0.35s var(--ease);
}

.btn:hover {
  transform: translateY(-1px);
}

.btn--primary {
  background: linear-gradient(135deg, var(--accent), var(--accent-deep));
  color: #140f0a;
  border-color: var(--accent);
}

.btn--primary:hover {
  color: #140f0a;
  background: linear-gradient(135deg, var(--accent-bright), var(--accent));
}

.btn--ghost {
  background: transparent;
  color: var(--text);
  border-color: var(--line-strong);
}

.btn--ghost:hover {
  border-color: var(--accent);
  color: var(--accent-bright);
}

.btn--text {
  background: transparent;
  border: none;
  color: var(--accent-bright);
  padding-inline: 0;
  text-decoration: underline;
  text-underline-offset: 0.2em;
}

.hero {
  position: relative;
  min-height: calc(100vh - var(--header-h));
  display: grid;
  align-items: end;
  overflow: hidden;
  isolation: isolate;
}

.hero__media {
  position: absolute;
  inset: 0;
  z-index: -2;
}

.hero__media img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  filter: saturate(0.75) brightness(0.45);
  transform: scale(1.04);
  animation: heroDrift 28s var(--ease) infinite alternate;
}

.hero__veil {
  position: absolute;
  inset: 0;
  z-index: -1;
  background:
    linear-gradient(90deg, rgba(8, 9, 11, 0.92) 0%, rgba(8, 9, 11, 0.55) 48%, rgba(8, 9, 11, 0.35) 100%),
    linear-gradient(0deg, rgba(8, 9, 11, 0.95) 0%, transparent 42%);
}

.hero__content {
  padding: clamp(4rem, 12vh, 7rem) 0 clamp(3rem, 8vh, 5rem);
  max-width: 38rem;
}

.hero__brand {
  font-family: var(--font-display);
  font-size: clamp(3rem, 8vw, 5.5rem);
  color: var(--text);
  margin: 0 0 0.35rem;
  letter-spacing: 0.02em;
  animation: fadeUp 1s var(--ease) both;
}

.hero__line {
  width: 4.5rem;
  height: 1px;
  background: var(--accent);
  margin: 0 0 1.4rem;
  animation: fadeUp 1s 0.12s var(--ease) both;
}

.hero__lede {
  font-size: 1.15rem;
  color: var(--text);
  max-width: 32rem;
  animation: fadeUp 1s 0.22s var(--ease) both;
}

.hero__cta {
  margin-top: 1.75rem;
  animation: fadeUp 1s 0.32s var(--ease) both;
}

@keyframes heroDrift {
  from {
    transform: scale(1.04) translate3d(0, 0, 0);
  }
  to {
    transform: scale(1.08) translate3d(-1.5%, 1%, 0);
  }
}

@keyframes fadeUp {
  from {
    opacity: 0;
    transform: translateY(18px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

[data-reveal] {
  opacity: 0;
  transform: translateY(22px);
  transition: opacity 0.8s var(--ease), transform 0.8s var(--ease);
}

[data-reveal].is-visible {
  opacity: 1;
  transform: none;
}

.section {
  padding: clamp(3.5rem, 8vw, 6rem) 0;
}

.section--tight {
  padding: clamp(2.5rem, 5vw, 3.5rem) 0;
}

.section--panel {
  background: linear-gradient(180deg, transparent, rgba(22, 25, 34, 0.65), transparent);
}

.eyebrow {
  font-size: 0.78rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 0.75rem;
}

.split {
  display: grid;
  gap: 2.5rem;
}

@media (min-width: 860px) {
  .split {
    grid-template-columns: 1.05fr 0.95fr;
    align-items: center;
  }

  .split--reverse > :first-child {
    order: 2;
  }
}

.frame {
  position: relative;
  overflow: hidden;
  border: 1px solid var(--line);
  box-shadow: var(--shadow);
}

.frame img {
  width: 100%;
  aspect-ratio: 4 / 3;
  object-fit: cover;
  transition: transform 1.2s var(--ease);
}

.frame:hover img {
  transform: scale(1.04);
}

.frame::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  border: 1px solid rgba(196, 165, 116, 0.12);
  margin: 0.65rem;
}

.benefit-list {
  list-style: none;
  padding: 0;
  margin: 1.5rem 0 0;
  display: grid;
  gap: 1.25rem;
}

.benefit-list li {
  padding-left: 1.25rem;
  border-left: 1px solid var(--accent);
}

.benefit-list strong {
  display: block;
  color: var(--text);
  font-weight: 600;
  margin-bottom: 0.25rem;
}

.metric-row {
  display: grid;
  gap: 1.5rem;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  padding: 2rem 0;
  margin: 2.5rem 0;
}

@media (min-width: 720px) {
  .metric-row {
    grid-template-columns: repeat(3, 1fr);
  }
}

.metric__value {
  font-family: var(--font-display);
  font-size: 2.6rem;
  color: var(--accent-bright);
  line-height: 1;
}

.metric__label {
  margin: 0.5rem 0 0;
  font-size: 0.92rem;
}

.course-grid,
.blog-grid,
.price-grid,
.review-grid {
  display: grid;
  gap: 1.75rem;
}

@media (min-width: 720px) {
  .course-grid,
  .blog-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .price-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

@media (min-width: 980px) {
  .course-grid--3,
  .blog-grid--3 {
    grid-template-columns: repeat(3, 1fr);
  }
}

.course-tile,
.blog-tile,
.price-tier,
.review-block {
  background: var(--bg-elevated);
  border: 1px solid var(--line);
  transition: border-color 0.4s var(--ease), transform 0.4s var(--ease);
}

.course-tile:hover,
.blog-tile:hover {
  border-color: var(--line-strong);
  transform: translateY(-3px);
}

.course-tile a,
.blog-tile a {
  text-decoration: none;
  color: inherit;
  display: block;
}

.course-tile__media,
.blog-tile__media {
  overflow: hidden;
  aspect-ratio: 16 / 10;
}

.course-tile__media img,
.blog-tile__media img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 1s var(--ease), filter 1s var(--ease);
  filter: saturate(0.85);
}

.course-tile:hover img,
.blog-tile:hover img {
  transform: scale(1.05);
  filter: saturate(1);
}

.course-tile__body,
.blog-tile__body,
.price-tier__body,
.review-block {
  padding: 1.35rem 1.4rem 1.5rem;
}

.course-tile h3,
.blog-tile h3,
.price-tier h3 {
  color: var(--text);
  margin-bottom: 0.4rem;
}

.meta {
  font-size: 0.82rem;
  letter-spacing: 0.04em;
  color: var(--accent);
  margin-bottom: 0.55rem;
}

.quote {
  font-family: var(--font-display);
  font-size: 1.35rem;
  color: var(--text);
  line-height: 1.4;
  margin: 0 0 1rem;
}

.quote--long {
  font-size: 1.15rem;
}

.attribution {
  font-size: 0.9rem;
  color: var(--text-muted);
  margin: 0;
}

.stars {
  color: var(--accent);
  letter-spacing: 0.12em;
  margin-bottom: 0.65rem;
  font-size: 0.85rem;
}

.price-tier {
  padding: 1.75rem 1.5rem;
  display: flex;
  flex-direction: column;
  min-height: 100%;
}

.price-tier--featured {
  border-color: var(--accent);
  background:
    linear-gradient(160deg, rgba(196, 165, 116, 0.1), transparent 55%),
    var(--bg-panel);
}

.price-tier__amount {
  font-family: var(--font-display);
  font-size: 2.4rem;
  color: var(--accent-bright);
  margin: 0.4rem 0 1rem;
}

.price-tier ul {
  list-style: none;
  padding: 0;
  margin: 0 0 1.5rem;
  flex: 1;
}

.price-tier li {
  padding: 0.45rem 0;
  border-bottom: 1px solid rgba(255, 255, 255, 0.05);
  color: var(--text-muted);
  font-size: 0.95rem;
}

.page-hero {
  padding: clamp(3rem, 8vw, 5rem) 0 2rem;
  border-bottom: 1px solid var(--line);
}

.page-hero h1 {
  max-width: 18ch;
}

.page-hero p {
  max-width: 40rem;
  font-size: 1.1rem;
}

.prose {
  max-width: 42rem;
}

.prose h2,
.prose h3 {
  margin-top: 2rem;
}

.prose ul,
.prose ol {
  color: var(--text-muted);
  padding-left: 1.2rem;
}

.prose li {
  margin-bottom: 0.45rem;
}

.prose table {
  width: 100%;
  border-collapse: collapse;
  margin: 1.5rem 0;
  font-size: 0.92rem;
}

.prose th,
.prose td {
  border: 1px solid var(--line);
  padding: 0.75rem 0.85rem;
  text-align: left;
  vertical-align: top;
}

.prose th {
  background: var(--bg-soft);
  color: var(--accent-bright);
  font-weight: 600;
}

.module-list {
  list-style: none;
  padding: 0;
  margin: 1.5rem 0;
  display: grid;
  gap: 0.85rem;
}

.module-list li {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 1rem;
  padding: 1rem 1.1rem;
  background: var(--bg-elevated);
  border: 1px solid var(--line);
}

.module-list span {
  font-family: var(--font-display);
  color: var(--accent);
  font-size: 1.25rem;
}

.instructor {
  display: grid;
  gap: 1.25rem;
  align-items: center;
  padding: 1.5rem;
  background: var(--bg-elevated);
  border: 1px solid var(--line);
}

@media (min-width: 640px) {
  .instructor {
    grid-template-columns: 140px 1fr;
  }
}

.instructor img {
  width: 140px;
  height: 140px;
  object-fit: cover;
  border-radius: 50%;
  border: 1px solid var(--line-strong);
}

.faq details {
  border-bottom: 1px solid var(--line);
  padding: 1rem 0;
}

.faq summary {
  cursor: pointer;
  color: var(--text);
  font-weight: 600;
  list-style: none;
}

.faq summary::-webkit-details-marker {
  display: none;
}

.faq details[open] summary {
  color: var(--accent-bright);
}

.faq p {
  margin-top: 0.75rem;
}

.contact-layout {
  display: grid;
  gap: 2.5rem;
}

@media (min-width: 860px) {
  .contact-layout {
    grid-template-columns: 1.1fr 0.9fr;
  }
}

.field {
  margin-bottom: 1.15rem;
}

.field label {
  display: block;
  margin-bottom: 0.4rem;
  font-size: 0.88rem;
  letter-spacing: 0.04em;
  color: var(--text);
}

.field input,
.field select,
.field textarea {
  width: 100%;
  padding: 0.85rem 0.95rem;
  background: var(--bg-soft);
  border: 1px solid var(--line);
  color: var(--text);
  font: inherit;
  transition: border-color 0.3s var(--ease);
}

.field input:focus,
.field select:focus,
.field textarea:focus {
  outline: none;
  border-color: var(--accent);
}

.field__error {
  margin: 0.35rem 0 0;
  color: var(--danger);
  font-size: 0.85rem;
}

.form-status {
  margin-top: 1rem;
  padding: 0.85rem 1rem;
  border: 1px solid var(--line);
}

.form-status--ok {
  border-color: var(--ok);
  color: var(--ok);
}

.form-status--err {
  border-color: var(--danger);
  color: var(--danger);
}

.contact-card {
  padding: 1.75rem;
  background: var(--bg-elevated);
  border: 1px solid var(--line);
}

.contact-card dt {
  font-size: 0.78rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--accent);
  margin-top: 1.1rem;
}

.contact-card dt:first-child {
  margin-top: 0;
}

.contact-card dd {
  margin: 0.35rem 0 0;
  color: var(--text);
}

.site-footer {
  margin-top: 3rem;
  border-top: 1px solid var(--line);
  background: #060708;
  padding: 3rem 0 2rem;
}

.footer-grid {
  display: grid;
  gap: 2rem;
}

@media (min-width: 800px) {
  .footer-grid {
    grid-template-columns: 1.4fr 1fr 1fr;
  }
}

.site-footer h2 {
  font-size: 1.1rem;
  color: var(--accent-bright);
  margin-bottom: 0.85rem;
}

.site-footer ul {
  list-style: none;
  padding: 0;
  margin: 0;
}

.site-footer li {
  margin-bottom: 0.45rem;
}

.site-footer a {
  color: var(--text-muted);
  text-decoration: none;
}

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

.footer-meta {
  margin-top: 2.5rem;
  padding-top: 1.25rem;
  border-top: 1px solid var(--line);
  font-size: 0.85rem;
  color: var(--text-muted);
}

.cookie-banner {
  position: fixed;
  inset: auto 0 0;
  z-index: 60;
  padding: 1rem;
  animation: fadeUp 0.55s var(--ease);
}

.cookie-banner__inner {
  width: min(100%, 920px);
  margin: 0 auto;
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  align-items: center;
  justify-content: space-between;
  padding: 1.1rem 1.25rem;
  background: var(--bg-panel);
  border: 1px solid var(--line-strong);
  box-shadow: var(--shadow);
}

.cookie-banner__text {
  margin: 0;
  flex: 1 1 280px;
  font-size: 0.92rem;
  color: var(--text-muted);
}

.cookie-banner__actions {
  display: flex;
  gap: 0.65rem;
}

.inline-error {
  margin: 0;
  padding: 0.75rem 1rem;
  background: rgba(201, 122, 106, 0.15);
  border-bottom: 1px solid var(--danger);
  color: var(--danger);
  font-size: 0.92rem;
}

.case-study {
  padding: 1.75rem;
  border: 1px solid var(--line);
  background: linear-gradient(180deg, var(--bg-elevated), var(--bg));
  margin-bottom: 1.5rem;
}

.case-study h3 {
  color: var(--text);
}

.cta-band {
  text-align: center;
  padding: clamp(3rem, 7vw, 4.5rem) 1.5rem;
  border: 1px solid var(--line);
  background:
    radial-gradient(ellipse at center, rgba(196, 165, 116, 0.12), transparent 65%),
    var(--bg-elevated);
}

.cta-band p {
  max-width: 34rem;
  margin-inline: auto;
}

.not-found {
  min-height: 70vh;
  display: grid;
  place-content: center;
  text-align: center;
  padding: 3rem 1.25rem;
}

.not-found .code {
  font-family: var(--font-display);
  font-size: clamp(5rem, 18vw, 9rem);
  color: var(--accent);
  line-height: 0.9;
  margin-bottom: 0.5rem;
}

.legal-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  margin: 1.5rem 0 2rem;
  font-size: 0.9rem;
}

.timeline {
  list-style: none;
  padding: 0;
  margin: 2rem 0 0;
  border-left: 1px solid var(--line-strong);
}

.timeline li {
  padding: 0 0 1.75rem 1.5rem;
  position: relative;
}

.timeline li::before {
  content: "";
  position: absolute;
  left: -4px;
  top: 0.45rem;
  width: 7px;
  height: 7px;
  background: var(--accent);
  border-radius: 50%;
}

.timeline strong {
  display: block;
  color: var(--text);
  margin-bottom: 0.25rem;
}