/* Intelligent Ia — modern minimalist, soft teal accents */
:root {
  --bg: #ffffff;
  --bg-soft: #f4f8f7;
  --bg-mist: #e8f2ef;
  --ink: #1a2e2a;
  --ink-muted: #5a6e68;
  --accent: #1a6b5c;
  --accent-soft: #7ec8b8;
  --accent-deep: #0f4a3f;
  --line: #d5e4df;
  --danger: #b33a3a;
  --success: #1a6b5c;
  --radius: 2px;
  --shadow: 0 12px 40px rgba(26, 46, 42, 0.06);
  --font-display: "Noto Serif KR", "Source Serif 4", Georgia, serif;
  --font-body: "Noto Sans KR", "Source Sans 3", sans-serif;
  --max: 1120px;
  --ease: cubic-bezier(0.22, 1, 0.36, 1);
}

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: var(--font-body);
  font-size: 1.05rem;
  line-height: 1.7;
  color: var(--ink);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
}

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

a {
  color: var(--accent);
  text-decoration-thickness: 1px;
  text-underline-offset: 3px;
}

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

h1, h2, h3, h4 {
  font-family: var(--font-display);
  font-weight: 600;
  line-height: 1.25;
  letter-spacing: -0.02em;
  color: var(--ink);
}

h1 { font-size: clamp(2.2rem, 5vw, 3.6rem); margin: 0 0 0.6em; }
h2 { font-size: clamp(1.6rem, 3vw, 2.25rem); margin: 0 0 0.55em; }
h3 { font-size: 1.25rem; margin: 0 0 0.4em; }

p { margin: 0 0 1em; color: var(--ink-muted); }

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

.inline-error {
  background: #fdecea;
  color: var(--danger);
  padding: 0.75rem 1.25rem;
  font-size: 0.95rem;
  text-align: center;
}

/* Header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 40;
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--line);
}

.site-header__inner {
  width: min(100% - 2.5rem, var(--max));
  margin-inline: auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 4.25rem;
  gap: 1.5rem;
}

.logo {
  font-family: var(--font-display);
  font-size: 1.35rem;
  font-weight: 600;
  color: var(--ink);
  text-decoration: none;
  letter-spacing: -0.03em;
}

.logo:hover { color: var(--accent); }

.logo--footer {
  margin: 0 0 0.75rem;
  font-size: 1.25rem;
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 1.35rem;
}

.site-nav a {
  color: var(--ink-muted);
  text-decoration: none;
  font-size: 0.95rem;
  transition: color 0.25s var(--ease);
}

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

.site-nav .nav-cta {
  color: #fff;
  background: var(--accent);
  padding: 0.45rem 0.95rem;
  border-radius: var(--radius);
}

.site-nav .nav-cta:hover {
  background: var(--accent-deep);
  color: #fff;
}

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: 0;
  cursor: pointer;
  padding: 0.4rem;
}

.nav-toggle span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--ink);
}

@media (max-width: 860px) {
  .nav-toggle { display: flex; }
  .site-nav {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: stretch;
    background: #fff;
    border-bottom: 1px solid var(--line);
    padding: 1rem 1.25rem 1.25rem;
    gap: 0;
    display: none;
  }
  .site-nav.is-open { display: flex; }
  .site-nav a {
    padding: 0.75rem 0;
    border-bottom: 1px solid var(--line);
  }
  .site-nav .nav-cta {
    margin-top: 0.75rem;
    text-align: center;
    border: 0;
  }
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.4rem;
  padding: 0.8rem 1.4rem;
  font-family: var(--font-body);
  font-size: 0.95rem;
  font-weight: 500;
  border: 1px solid transparent;
  border-radius: var(--radius);
  cursor: pointer;
  text-decoration: none;
  transition: background 0.25s var(--ease), color 0.25s var(--ease), border-color 0.25s var(--ease), transform 0.25s var(--ease);
}

.btn:hover { transform: translateY(-1px); }
.btn:disabled { opacity: 0.6; cursor: not-allowed; transform: none; }

.btn--primary {
  background: var(--accent);
  color: #fff;
}
.btn--primary:hover {
  background: var(--accent-deep);
  color: #fff;
}

.btn--ghost {
  background: transparent;
  border-color: var(--line);
  color: var(--ink);
}
.btn--ghost:hover {
  border-color: var(--accent);
  color: var(--accent);
}

.btn--light {
  background: #fff;
  color: var(--accent-deep);
}
.btn--light:hover {
  background: var(--bg-mist);
  color: var(--accent-deep);
}

/* Hero — home: brand-led, full-bleed image plane */
.hero-home {
  position: relative;
  min-height: min(92vh, 780px);
  display: grid;
  align-items: end;
  overflow: hidden;
  background: var(--bg-mist);
}

.hero-home__media {
  position: absolute;
  inset: 0;
  z-index: 0;
}

.hero-home__media img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  animation: heroZoom 18s var(--ease) infinite alternate;
}

.hero-home__veil {
  position: absolute;
  inset: 0;
  background: linear-gradient(
    180deg,
    rgba(255, 255, 255, 0.15) 0%,
    rgba(247, 250, 249, 0.55) 45%,
    rgba(255, 255, 255, 0.96) 100%
  );
  z-index: 1;
}

.hero-home__content {
  position: relative;
  z-index: 2;
  width: min(100% - 2.5rem, var(--max));
  margin: 0 auto;
  padding: 5rem 0 4rem;
  animation: fadeUp 0.9s var(--ease) both;
}

.hero-home__brand {
  font-family: var(--font-display);
  font-size: clamp(2.8rem, 7vw, 5rem);
  font-weight: 600;
  letter-spacing: -0.04em;
  color: var(--ink);
  margin: 0 0 0.35em;
  line-height: 1.05;
}

.hero-home__line {
  font-size: clamp(1.15rem, 2.2vw, 1.45rem);
  color: var(--ink);
  max-width: 32ch;
  margin: 0 0 1.5rem;
  font-weight: 400;
}

.hero-home__cta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
}

@keyframes heroZoom {
  from { transform: scale(1); }
  to { transform: scale(1.06); }
}

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

@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

.reveal {
  animation: fadeUp 0.8s var(--ease) both;
}

/* Page heroes (inner) */
.page-hero {
  padding: 4.5rem 0 3rem;
  background:
    radial-gradient(ellipse 80% 60% at 90% 0%, var(--bg-mist), transparent 55%),
    linear-gradient(180deg, var(--bg-soft), var(--bg));
  border-bottom: 1px solid var(--line);
}

.page-hero p.lead {
  font-size: 1.15rem;
  max-width: 42rem;
  color: var(--ink-muted);
}

.eyebrow {
  display: block;
  font-size: 0.8rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 0.75rem;
  font-weight: 600;
}

/* Sections */
.section {
  padding: 4.5rem 0;
}

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

.section--accent {
  background: linear-gradient(135deg, var(--accent-deep), var(--accent));
  color: #fff;
}

.section--accent h2,
.section--accent p {
  color: #fff;
}

.section--accent p { opacity: 0.9; }

.section-head {
  max-width: 38rem;
  margin-bottom: 2.5rem;
}

.split {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 3rem;
  align-items: center;
}

@media (max-width: 800px) {
  .split { grid-template-columns: 1fr; gap: 2rem; }
}

/* Feature list (not cards) */
.feature-rows {
  display: grid;
  gap: 0;
  border-top: 1px solid var(--line);
}

.feature-row {
  display: grid;
  grid-template-columns: 4rem 1fr;
  gap: 1.25rem;
  padding: 1.75rem 0;
  border-bottom: 1px solid var(--line);
  transition: background 0.3s var(--ease);
}

.feature-row:hover {
  background: var(--bg-soft);
}

.feature-row__num {
  font-family: var(--font-display);
  font-size: 1.5rem;
  color: var(--accent-soft);
}

/* Course / blog list items */
.item-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 2rem;
}

@media (max-width: 900px) {
  .item-grid { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 600px) {
  .item-grid { grid-template-columns: 1fr; }
}

.item {
  display: flex;
  flex-direction: column;
  gap: 0.85rem;
}

.item__media {
  overflow: hidden;
  aspect-ratio: 16 / 10;
  background: var(--bg-mist);
}

.item__media img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.6s var(--ease);
}

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

.item__meta {
  font-size: 0.85rem;
  color: var(--accent);
  letter-spacing: 0.02em;
}

.item h3 {
  margin: 0;
}

.item h3 a {
  color: var(--ink);
  text-decoration: none;
}

.item h3 a:hover { color: var(--accent); }

.item p {
  margin: 0;
  font-size: 0.98rem;
}

/* Proof / numbers strip */
.proof-strip {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 2rem;
  padding: 2.5rem 0;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.proof-strip strong {
  display: block;
  font-family: var(--font-display);
  font-size: clamp(1.8rem, 3vw, 2.4rem);
  color: var(--ink);
  letter-spacing: -0.03em;
}

.proof-strip span {
  font-size: 0.95rem;
  color: var(--ink-muted);
}

@media (max-width: 640px) {
  .proof-strip { grid-template-columns: 1fr; gap: 1.5rem; }
}

/* Quotes */
.quote-block {
  max-width: 40rem;
  padding: 0;
  margin: 0;
  border: 0;
}

.quote-block p {
  font-family: var(--font-display);
  font-size: clamp(1.2rem, 2.2vw, 1.55rem);
  color: var(--ink);
  line-height: 1.55;
  margin-bottom: 1rem;
}

.quote-block footer {
  font-size: 0.9rem;
  color: var(--ink-muted);
  font-style: normal;
}

.quote-list {
  display: grid;
  gap: 2.5rem;
}

.quote-list article {
  padding-bottom: 2rem;
  border-bottom: 1px solid var(--line);
}

.quote-list article:last-child {
  border-bottom: 0;
  padding-bottom: 0;
}

.stars {
  color: var(--accent);
  letter-spacing: 0.1em;
  font-size: 0.85rem;
  margin-bottom: 0.5rem;
}

/* Pricing */
.price-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
  align-items: stretch;
}

@media (max-width: 800px) {
  .price-grid { grid-template-columns: 1fr; }
}

.price-tier {
  padding: 2rem 1.75rem;
  border: 1px solid var(--line);
  background: #fff;
  display: flex;
  flex-direction: column;
  gap: 1rem;
  transition: border-color 0.3s var(--ease), box-shadow 0.3s var(--ease);
}

.price-tier:hover {
  border-color: var(--accent-soft);
  box-shadow: var(--shadow);
}

.price-tier--featured {
  border-color: var(--accent);
  background: var(--bg-soft);
}

.price-tier__name {
  font-family: var(--font-display);
  font-size: 1.35rem;
  margin: 0;
  color: var(--ink);
}

.price-tier__amount {
  font-family: var(--font-display);
  font-size: 2.1rem;
  color: var(--ink);
  letter-spacing: -0.03em;
}

.price-tier__amount small {
  font-size: 0.95rem;
  color: var(--ink-muted);
  font-family: var(--font-body);
}

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

.price-tier li {
  padding: 0.45rem 0;
  border-bottom: 1px solid var(--line);
  font-size: 0.95rem;
  color: var(--ink-muted);
}

.price-note {
  font-size: 0.9rem;
  margin-top: 1.5rem;
  color: var(--ink-muted);
}

/* Forms */
.form-panel {
  max-width: 36rem;
}

.form-field {
  margin-bottom: 1.25rem;
}

.form-field label {
  display: block;
  font-size: 0.9rem;
  font-weight: 500;
  margin-bottom: 0.4rem;
  color: var(--ink);
}

.form-field input,
.form-field select,
.form-field textarea {
  width: 100%;
  padding: 0.75rem 0.9rem;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  font-family: var(--font-body);
  font-size: 1rem;
  color: var(--ink);
  background: #fff;
  transition: border-color 0.2s;
}

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

.form-field textarea { min-height: 140px; resize: vertical; }

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

.form-status {
  margin-top: 1rem;
  font-size: 0.95rem;
}

.form-status--success { color: var(--success); }
.form-status--error { color: var(--danger); }

.contact-aside {
  padding: 1.75rem 0;
  border-top: 1px solid var(--line);
}

.contact-aside h3 { margin-top: 1.5rem; }
.contact-aside address {
  font-style: normal;
  color: var(--ink-muted);
  line-height: 1.6;
}

/* FAQ */
.faq details {
  border-bottom: 1px solid var(--line);
  padding: 1.1rem 0;
}

.faq summary {
  cursor: pointer;
  font-weight: 500;
  color: var(--ink);
  list-style: none;
}

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

.faq summary::after {
  content: "+";
  float: right;
  color: var(--accent);
}

.faq details[open] summary::after { content: "–"; }

.faq details p {
  margin: 0.75rem 0 0.25rem;
  padding-right: 1.5rem;
}

/* Modules */
.module-list {
  list-style: none;
  padding: 0;
  margin: 0;
  counter-reset: mod;
}

.module-list li {
  counter-increment: mod;
  padding: 1.25rem 0 1.25rem 3.5rem;
  border-bottom: 1px solid var(--line);
  position: relative;
}

.module-list li::before {
  content: counter(mod, decimal-leading-zero);
  position: absolute;
  left: 0;
  top: 1.25rem;
  font-family: var(--font-display);
  color: var(--accent-soft);
  font-size: 1.1rem;
}

/* Tables */
.data-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.95rem;
  margin: 1.5rem 0;
}

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

.data-table th {
  color: var(--ink);
  font-weight: 600;
  background: var(--bg-soft);
}

/* Legal */
.legal-body {
  max-width: 44rem;
  padding: 3rem 0 5rem;
}

.legal-body h2 {
  margin-top: 2.5rem;
  font-size: 1.35rem;
}

.legal-body ul {
  color: var(--ink-muted);
  padding-left: 1.25rem;
}

/* Cookie banner */
.cookie-banner {
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  z-index: 50;
  background: #fff;
  border-top: 1px solid var(--line);
  box-shadow: 0 -8px 30px rgba(26, 46, 42, 0.08);
  animation: fadeUp 0.5s var(--ease) both;
}

.cookie-banner__inner {
  width: min(100% - 2rem, var(--max));
  margin: 0 auto;
  padding: 1.25rem 0;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
  flex-wrap: wrap;
}

.cookie-banner__inner p {
  margin: 0;
  flex: 1;
  min-width: 220px;
  font-size: 0.95rem;
}

.cookie-banner__actions {
  display: flex;
  gap: 0.6rem;
}

/* Footer */
.site-footer {
  background: var(--bg-soft);
  border-top: 1px solid var(--line);
  padding: 3.5rem 0 2rem;
  margin-top: 0;
}

.site-footer__grid {
  width: min(100% - 2.5rem, var(--max));
  margin: 0 auto 2.5rem;
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr 1.3fr;
  gap: 2rem;
}

@media (max-width: 800px) {
  .site-footer__grid { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 500px) {
  .site-footer__grid { grid-template-columns: 1fr; }
}

.site-footer__tag {
  font-size: 0.95rem;
  max-width: 28ch;
}

.footer-label {
  font-size: 0.8rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--ink);
  font-weight: 600;
  margin: 0 0 0.85rem;
}

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

.footer-links a {
  color: var(--ink-muted);
  text-decoration: none;
  font-size: 0.95rem;
  display: inline-block;
  padding: 0.25rem 0;
}

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

.footer-address {
  font-style: normal;
  font-size: 0.9rem;
  color: var(--ink-muted);
  margin-bottom: 0.75rem;
  line-height: 1.55;
}

.site-footer__bottom {
  width: min(100% - 2.5rem, var(--max));
  margin: 0 auto;
  padding-top: 1.5rem;
  border-top: 1px solid var(--line);
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 1rem;
  font-size: 0.85rem;
  color: var(--ink-muted);
}

.site-footer__bottom p { margin: 0; color: inherit; }

.footer-legal {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
}

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

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

/* 404 */
.not-found {
  min-height: 60vh;
  display: grid;
  place-content: center;
  text-align: center;
  padding: 4rem 1.5rem;
}

.not-found .code {
  font-family: var(--font-display);
  font-size: clamp(4rem, 12vw, 7rem);
  color: var(--accent-soft);
  line-height: 1;
  margin: 0;
}

/* Case study */
.case {
  padding: 2rem 0;
  border-top: 1px solid var(--line);
}

.case h3 { margin-top: 0; }

.instructor {
  display: grid;
  grid-template-columns: 120px 1fr;
  gap: 1.5rem;
  align-items: start;
}

.instructor img {
  width: 120px;
  height: 120px;
  object-fit: cover;
  border-radius: 50%;
}

@media (max-width: 500px) {
  .instructor { grid-template-columns: 1fr; }
}

.prose {
  max-width: 42rem;
}

.prose h2 { margin-top: 2.5rem; }

.meta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  font-size: 0.9rem;
  color: var(--ink-muted);
  margin-bottom: 2rem;
}

.cover-wide {
  aspect-ratio: 21 / 9;
  overflow: hidden;
  margin: 0 0 2.5rem;
  background: var(--bg-mist);
}

.cover-wide img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.cta-band {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
}

.cta-band h2 { margin: 0; color: #fff; }
.cta-band p { margin: 0.4rem 0 0; max-width: 36ch; }

.outcome-list {
  list-style: none;
  padding: 0;
  margin: 0;
}

.outcome-list li {
  padding: 0.65rem 0 0.65rem 1.5rem;
  position: relative;
  color: var(--ink-muted);
  border-bottom: 1px solid var(--line);
}

.outcome-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 1.1rem;
  width: 8px;
  height: 8px;
  background: var(--accent-soft);
  border-radius: 50%;
}