:root {
  --bg: #ffffff;
  --bg-soft: #f5f8f7;
  --bg-mist: #eef4f2;
  --text: #18222b;
  --text-muted: #5c6b75;
  --accent: #1e7a6e;
  --accent-hover: #16655b;
  --accent-soft: #d8ece8;
  --accent-line: #a8d5ce;
  --border: #dde5e2;
  --danger: #b42318;
  --success: #0f6b4c;
  --shadow: 0 12px 40px rgba(24, 34, 43, 0.06);
  --radius: 4px;
  --font-display: "Fraunces", "Noto Serif KR", Georgia, serif;
  --font-body: "Noto Sans KR", "Source Sans 3", sans-serif;
  --max: 1120px;
  --header-h: 72px;
  --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(--text);
  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-hover);
}

h1, h2, h3, h4 {
  font-family: var(--font-display);
  font-weight: 560;
  line-height: 1.25;
  letter-spacing: -0.02em;
  margin: 0 0 0.6em;
}

h1 { font-size: clamp(2.2rem, 5vw, 3.6rem); }
h2 { font-size: clamp(1.6rem, 3vw, 2.25rem); }
h3 { font-size: 1.25rem; }

p { margin: 0 0 1rem; }

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  border: 0;
}

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

.site-header {
  position: sticky;
  top: 0;
  z-index: 40;
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid transparent;
  transition: border-color 0.3s var(--ease), box-shadow 0.3s var(--ease);
}

.site-header.is-scrolled {
  border-bottom-color: var(--border);
  box-shadow: 0 4px 20px rgba(24, 34, 43, 0.04);
}

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

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.65rem;
  color: var(--text);
  text-decoration: none;
}

.brand-mark {
  width: 1.35rem;
  height: 1.35rem;
  border-radius: 4px;
  background: linear-gradient(145deg, var(--accent) 0%, #3aa898 100%);
  box-shadow: 0 0 0 3px var(--accent-soft);
  animation: mark-pulse 4.5s var(--ease) infinite;
}

@keyframes mark-pulse {
  0%, 100% { box-shadow: 0 0 0 3px var(--accent-soft); }
  50% { box-shadow: 0 0 0 5px rgba(216, 236, 232, 0.35); }
}

.brand-name {
  font-family: var(--font-display);
  font-size: 1.35rem;
  font-weight: 600;
  letter-spacing: -0.03em;
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 0.15rem 1.15rem;
  flex-wrap: wrap;
}

.site-nav a {
  color: var(--text-muted);
  text-decoration: none;
  font-size: 0.92rem;
  font-weight: 500;
  transition: color 0.2s ease;
}

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

.site-nav .nav-cta {
  color: #fff;
  background: var(--accent);
  padding: 0.45rem 0.95rem;
  border-radius: var(--radius);
  transition: background 0.2s ease, transform 0.2s var(--ease);
}

.site-nav .nav-cta:hover {
  background: var(--accent-hover);
  color: #fff;
  transform: translateY(-1px);
}

.nav-toggle {
  display: none;
  background: none;
  border: 0;
  padding: 0.4rem;
  cursor: pointer;
}

.nav-toggle-bar {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--text);
  margin: 5px 0;
  transition: transform 0.25s var(--ease);
}

@media (max-width: 900px) {
  .nav-toggle { display: block; }
  .site-nav {
    display: none;
    position: absolute;
    top: var(--header-h);
    left: 0;
    right: 0;
    background: #fff;
    border-bottom: 1px solid var(--border);
    padding: 1rem 1.25rem 1.4rem;
    flex-direction: column;
    align-items: flex-start;
    gap: 0.85rem;
  }
  .site-nav.is-open { display: flex; }
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.4rem;
  padding: 0.85rem 1.4rem;
  border-radius: var(--radius);
  border: 1px solid transparent;
  font-family: var(--font-body);
  font-size: 0.98rem;
  font-weight: 600;
  text-decoration: none;
  cursor: pointer;
  transition: background 0.2s ease, color 0.2s ease, border-color 0.2s ease, transform 0.2s var(--ease);
}

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

.btn-primary:hover {
  background: var(--accent-hover);
  color: #fff;
  transform: translateY(-1px);
}

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

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

.hero-panel {
  position: relative;
  min-height: calc(100vh - var(--header-h));
  display: grid;
  align-items: end;
  overflow: hidden;
  background: #0f2f2b;
}

.hero-panel__media {
  position: absolute;
  inset: 0;
}

.hero-panel__media img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  animation: hero-drift 18s ease-in-out infinite alternate;
}

@keyframes hero-drift {
  from { transform: scale(1.02); }
  to { transform: scale(1.08); }
}

.hero-panel__shade {
  position: absolute;
  inset: 0;
  background:
    linear-gradient(180deg, rgba(15, 47, 43, 0.35) 0%, rgba(15, 47, 43, 0.78) 100%),
    linear-gradient(90deg, rgba(15, 47, 43, 0.55) 0%, rgba(15, 47, 43, 0.15) 70%);
}

.hero-panel__content {
  position: relative;
  z-index: 1;
  width: min(100% - 2.5rem, var(--max));
  margin: 0 auto;
  padding: 4.5rem 0 4rem;
  color: #fff;
  max-width: 38rem;
  animation: rise-in 0.9s var(--ease) both;
}

@keyframes rise-in {
  from { opacity: 0; transform: translateY(22px); }
  to { opacity: 1; transform: translateY(0); }
}

.hero-panel__brand {
  font-family: var(--font-display);
  font-size: clamp(2.8rem, 7vw, 5rem);
  font-weight: 620;
  letter-spacing: -0.04em;
  line-height: 1.05;
  margin: 0 0 1rem;
}

.hero-panel__lead {
  font-size: 1.12rem;
  color: rgba(255, 255, 255, 0.88);
  margin-bottom: 1.75rem;
  max-width: 32rem;
}

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

.hero-panel .btn-primary:hover {
  background: var(--accent-soft);
  color: var(--accent-hover);
}

.section {
  padding: 5rem 0;
}

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

.section-head {
  max-width: 36rem;
  margin-bottom: 2.5rem;
}

.section-head p {
  color: var(--text-muted);
}

.eyebrow {
  display: inline-block;
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 0.75rem;
}

.proof-strip {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
  padding: 2.25rem 0;
  border-block: 1px solid var(--border);
}

.proof-item strong {
  display: block;
  font-family: var(--font-display);
  font-size: 2rem;
  font-weight: 600;
  color: var(--accent);
  letter-spacing: -0.03em;
}

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

@media (max-width: 700px) {
  .proof-strip { grid-template-columns: 1fr; gap: 1.1rem; }
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 2rem 1.75rem;
}

.feature-item {
  padding-top: 1.25rem;
  border-top: 2px solid var(--accent-line);
}

.feature-item h3 {
  margin-bottom: 0.5rem;
}

.feature-item p {
  color: var(--text-muted);
  margin: 0;
}

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

.course-preview {
  display: grid;
  grid-template-columns: 1.15fr 1fr;
  gap: 2.5rem;
  align-items: center;
}

.course-preview__media {
  overflow: hidden;
  border-radius: var(--radius);
  min-height: 320px;
}

.course-preview__media img {
  width: 100%;
  height: 100%;
  min-height: 320px;
  object-fit: cover;
  transition: transform 0.7s var(--ease);
}

.course-preview:hover .course-preview__media img {
  transform: scale(1.04);
}

.course-preview__meta {
  color: var(--text-muted);
  font-size: 0.92rem;
  margin-bottom: 1rem;
}

@media (max-width: 850px) {
  .course-preview { grid-template-columns: 1fr; }
}

.quote-list {
  display: grid;
  gap: 1.75rem;
}

.quote {
  padding: 1.5rem 0 0;
  border-top: 1px solid var(--border);
}

.quote p {
  font-size: 1.08rem;
  margin-bottom: 0.75rem;
}

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

.cta-band {
  background:
    linear-gradient(135deg, rgba(30, 122, 110, 0.92), rgba(15, 47, 43, 0.95)),
    url("https://images.unsplash.com/photo-1551288049-bebda4e38f71?auto=format&fit=crop&w=1600&q=80") center/cover;
  color: #fff;
  padding: 4.5rem 0;
}

.cta-band h2 { color: #fff; }
.cta-band p { color: rgba(255, 255, 255, 0.88); max-width: 34rem; }
.cta-band .btn-primary {
  background: #fff;
  color: var(--accent);
}

.page-hero {
  padding: 3.5rem 0 2.5rem;
  background:
    linear-gradient(180deg, var(--bg-mist), var(--bg));
}

.page-hero h1 { margin-bottom: 0.6rem; }
.page-hero p {
  color: var(--text-muted);
  max-width: 38rem;
  margin: 0;
}

.page-hero--media {
  position: relative;
  min-height: 280px;
  display: flex;
  align-items: flex-end;
  color: #fff;
  overflow: hidden;
}

.page-hero--media img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.page-hero--media .shade {
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(15, 47, 43, 0.2), rgba(15, 47, 43, 0.82));
}

.page-hero--media .container {
  position: relative;
  z-index: 1;
  padding-bottom: 2.5rem;
  padding-top: 5rem;
}

.page-hero--media p { color: rgba(255, 255, 255, 0.88); }

.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 1.75rem;
}

.course-card,
.blog-card {
  display: flex;
  flex-direction: column;
  height: 100%;
  text-decoration: none;
  color: inherit;
  border-top: 2px solid var(--accent-line);
  padding-top: 1rem;
  transition: border-color 0.2s ease;
}

.course-card:hover,
.blog-card:hover {
  border-color: var(--accent);
}

.course-card img,
.blog-card img {
  width: 100%;
  aspect-ratio: 16 / 10;
  object-fit: cover;
  margin-bottom: 1rem;
  border-radius: var(--radius);
}

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

.course-card p,
.blog-card p {
  color: var(--text-muted);
  font-size: 0.95rem;
  flex: 1;
}

.meta-row {
  color: var(--text-muted);
  font-size: 0.85rem;
  margin-top: 0.75rem;
}

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

.price-tier {
  padding: 1.75rem;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
}

.price-tier.is-featured {
  border-color: var(--accent);
  box-shadow: var(--shadow);
  background: linear-gradient(180deg, #fff, var(--bg-soft));
}

.price-tier h3 {
  margin-bottom: 0.35rem;
}

.price-tier .price {
  font-family: var(--font-display);
  font-size: 2.1rem;
  color: var(--accent);
  margin: 0.8rem 0 1rem;
}

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

.price-tier li {
  position: relative;
  padding-left: 1.1rem;
  margin-bottom: 0.55rem;
  color: var(--text-muted);
  font-size: 0.95rem;
}

.price-tier li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.55em;
  width: 0.45rem;
  height: 0.45rem;
  border-radius: 50%;
  background: var(--accent-line);
}

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

.prose {
  max-width: 42rem;
}

.prose h2 { margin-top: 2.25rem; }
.prose h3 { margin-top: 1.75rem; }
.prose ul, .prose ol { padding-left: 1.25rem; color: var(--text-muted); }
.prose li { margin-bottom: 0.4rem; }
.prose table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.92rem;
  margin: 1.25rem 0;
}

.prose th,
.prose td {
  border: 1px solid var(--border);
  padding: 0.65rem 0.75rem;
  text-align: left;
  vertical-align: top;
}

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

.modules {
  display: grid;
  gap: 1rem;
}

.module {
  padding: 1.15rem 1.25rem;
  background: var(--bg-soft);
  border-left: 3px solid var(--accent);
}

.module h3 { margin-bottom: 0.35rem; }
.module p { margin: 0; color: var(--text-muted); font-size: 0.95rem; }

.instructor {
  display: grid;
  grid-template-columns: 120px 1fr;
  gap: 1.25rem;
  align-items: center;
  padding: 1.25rem 0;
}

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

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

.faq summary {
  cursor: pointer;
  font-weight: 600;
  list-style: none;
}

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

.faq details p {
  color: var(--text-muted);
  margin: 0.75rem 0 0;
}

.form {
  display: grid;
  gap: 1.1rem;
  max-width: 36rem;
}

.form-row {
  display: grid;
  gap: 0.4rem;
}

.form label {
  font-weight: 600;
  font-size: 0.92rem;
}

.form input,
.form select,
.form textarea {
  font: inherit;
  padding: 0.75rem 0.9rem;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: #fff;
  color: var(--text);
  width: 100%;
}

.form input:focus,
.form select:focus,
.form textarea:focus {
  outline: 2px solid var(--accent-soft);
  border-color: var(--accent);
}

.form .error {
  color: var(--danger);
  font-size: 0.85rem;
  min-height: 1.1em;
}

.form-status {
  padding: 0.85rem 1rem;
  border-radius: var(--radius);
  display: none;
}

.form-status.is-success {
  display: block;
  background: #e7f6ef;
  color: var(--success);
}

.form-status.is-error {
  display: block;
  background: #fdecea;
  color: var(--danger);
}

.contact-layout {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 3rem;
}

.contact-aside {
  background: var(--bg-soft);
  padding: 1.5rem;
  border-radius: var(--radius);
  height: fit-content;
}

.contact-aside h2 {
  font-size: 1.2rem;
  margin-bottom: 1rem;
}

.contact-aside p {
  color: var(--text-muted);
  font-size: 0.95rem;
}

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

.review-stack {
  display: grid;
  gap: 2rem;
}

.review-block {
  padding-bottom: 2rem;
  border-bottom: 1px solid var(--border);
}

.review-block .rating {
  color: var(--accent);
  font-weight: 700;
  font-size: 0.9rem;
  margin-bottom: 0.5rem;
}

.case-study {
  background: var(--bg-soft);
  padding: 2rem;
  border-radius: var(--radius);
  margin-top: 1rem;
}

.site-footer {
  background: #12201d;
  color: rgba(255, 255, 255, 0.78);
  padding: 3.5rem 0 2rem;
  margin-top: 2rem;
}

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

.footer-logo {
  font-family: var(--font-display);
  font-size: 1.5rem;
  color: #fff;
  margin-bottom: 0.5rem;
}

.footer-tag {
  max-width: 22rem;
  font-size: 0.95rem;
}

.footer-cols {
  display: grid;
  grid-template-columns: 1.4fr repeat(3, 1fr) 1.4fr;
  gap: 1.5rem;
  margin: 2.5rem 0;
}

.footer-brand { grid-column: 1; }

.footer-col h3 {
  color: #fff;
  font-size: 0.85rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  margin-bottom: 0.85rem;
}

.footer-col a {
  display: block;
  color: rgba(255, 255, 255, 0.72);
  text-decoration: none;
  margin-bottom: 0.45rem;
  font-size: 0.92rem;
}

.footer-col a:hover { color: #fff; }

.footer-contact p {
  font-size: 0.88rem;
  margin-bottom: 0.65rem;
  word-break: break-word;
}

.footer-contact a { display: inline; color: var(--accent-line); }

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.12);
  padding-top: 1.25rem;
  font-size: 0.85rem;
}

@media (max-width: 900px) {
  .footer-cols {
    grid-template-columns: 1fr 1fr;
  }
  .footer-brand { grid-column: 1 / -1; }
}

.cookie-banner {
  position: fixed;
  left: 1rem;
  right: 1rem;
  bottom: 1rem;
  z-index: 60;
  max-width: 420px;
  margin-left: auto;
  background: #fff;
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
  padding: 1.25rem;
  border-radius: var(--radius);
  animation: rise-in 0.45s var(--ease) both;
}

.cookie-banner p {
  font-size: 0.92rem;
  color: var(--text-muted);
  margin-bottom: 1rem;
}

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

.cookie-actions .btn {
  padding: 0.6rem 1rem;
  font-size: 0.9rem;
}

.inline-error {
  background: #fdecea;
  color: var(--danger);
  padding: 0.75rem 1rem;
  border-radius: var(--radius);
  margin: 0.75rem 0;
  font-size: 0.92rem;
}

.not-found {
  min-height: 60vh;
  display: grid;
  place-items: center;
  text-align: center;
  padding: 4rem 1.25rem;
}

.not-found .code {
  font-family: var(--font-display);
  font-size: 5rem;
  color: var(--accent);
  line-height: 1;
  margin-bottom: 0.5rem;
}

.article-cover {
  width: 100%;
  max-height: 420px;
  object-fit: cover;
  border-radius: var(--radius);
  margin: 1.5rem 0 2rem;
}

.split-2 {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 2rem;
}

@media (max-width: 750px) {
  .split-2 { grid-template-columns: 1fr; }
}

.reveal {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity 0.7s var(--ease), transform 0.7s var(--ease);
}

.reveal.is-visible {
  opacity: 1;
  transform: translateY(0);
}