:root {
  --bg: #f3f5f7;
  --bg-deep: #e8ecef;
  --surface: #ffffff;
  --ink: #1b2228;
  --ink-soft: #4a5560;
  --line: #d5dce2;
  --accent: #2f5d62;
  --accent-hover: #244a4e;
  --accent-soft: #dce9e8;
  --accent-mist: #a8c5c0;
  --warn: #8a4b2e;
  --radius: 10px;
  --shadow: 0 18px 40px rgba(27, 34, 40, 0.08);
  --font-display: "Hahmlet", "Noto Serif KR", serif;
  --font-body: "IBM Plex Sans KR", "Noto Sans KR", 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(--ink);
  background:
    radial-gradient(1200px 600px at 10% -10%, rgba(168, 197, 192, 0.35), transparent 55%),
    radial-gradient(900px 500px at 100% 0%, rgba(47, 93, 98, 0.08), transparent 50%),
    linear-gradient(180deg, var(--bg) 0%, #eef1f4 100%);
  min-height: 100vh;
}

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

a {
  color: var(--accent);
  text-decoration-thickness: 1px;
  text-underline-offset: 0.18em;
}

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

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

p {
  margin: 0 0 1rem;
}

ul {
  padding-left: 1.2rem;
}

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

.skip-link {
  position: absolute;
  left: 1rem;
  top: -3rem;
  background: var(--ink);
  color: #fff;
  padding: 0.6rem 1rem;
  z-index: 1000;
  border-radius: 6px;
}

.skip-link:focus {
  top: 1rem;
}

.container {
  width: min(100% - 2rem, var(--max));
  margin-inline: auto;
}

.narrow {
  width: min(100% - 2rem, 720px);
  margin-inline: auto;
}

/* Header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: blur(14px);
  background: rgba(243, 245, 247, 0.86);
  border-bottom: 1px solid rgba(213, 220, 226, 0.8);
}

.header-inner {
  width: min(100% - 2rem, var(--max));
  margin-inline: auto;
  min-height: var(--header-h);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

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

.logo-mark {
  width: 28px;
  height: 28px;
  border-radius: 7px;
  background:
    linear-gradient(145deg, var(--accent) 0%, #3d7a7f 55%, var(--accent-mist) 100%);
  box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.2);
}

.logo-text {
  font-family: var(--font-display);
  font-size: 1.35rem;
  font-weight: 700;
  letter-spacing: -0.03em;
}

.site-nav .nav-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  align-items: center;
  gap: 0.15rem 1.1rem;
  flex-wrap: wrap;
}

.site-nav a {
  text-decoration: none;
  color: var(--ink-soft);
  font-size: 0.95rem;
  font-weight: 500;
}

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

.nav-cta {
  display: inline-flex;
  align-items: center;
  padding: 0.45rem 0.9rem;
  border-radius: 999px;
  background: var(--accent);
  color: #fff !important;
  transition: background 0.25s var(--ease), transform 0.25s var(--ease);
}

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

.nav-toggle {
  display: none;
  background: transparent;
  border: 1px solid var(--line);
  border-radius: 8px;
  width: 44px;
  height: 44px;
  cursor: pointer;
  align-items: center;
  justify-content: center;
}

.nav-toggle-bar,
.nav-toggle-bar::before,
.nav-toggle-bar::after {
  display: block;
  width: 18px;
  height: 2px;
  background: var(--ink);
  position: relative;
  transition: transform 0.25s var(--ease);
}

.nav-toggle-bar::before,
.nav-toggle-bar::after {
  content: "";
  position: absolute;
  left: 0;
}

.nav-toggle-bar::before { top: -6px; }
.nav-toggle-bar::after { top: 6px; }

@media (max-width: 920px) {
  .nav-toggle { display: inline-flex; }
  .site-nav {
    position: absolute;
    left: 0;
    right: 0;
    top: 100%;
    background: rgba(255, 255, 255, 0.98);
    border-bottom: 1px solid var(--line);
    padding: 0.75rem 1rem 1.25rem;
    display: none;
  }
  .site-nav.is-open { display: block; }
  .site-nav .nav-list {
    flex-direction: column;
    align-items: flex-start;
    gap: 0.85rem;
  }
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.4rem;
  padding: 0.8rem 1.35rem;
  border-radius: 999px;
  border: 1px solid transparent;
  font-family: var(--font-body);
  font-size: 0.98rem;
  font-weight: 560;
  text-decoration: none;
  cursor: pointer;
  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-primary {
  background: var(--accent);
  color: #fff;
}

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

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

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

.btn-group {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
}

/* Hero variants */
.hero-bleed {
  position: relative;
  min-height: min(88vh, 820px);
  display: grid;
  align-items: end;
  color: #fff;
  overflow: hidden;
}

.hero-bleed::before {
  content: "";
  position: absolute;
  inset: 0;
  background:
    linear-gradient(180deg, rgba(27, 34, 40, 0.15) 0%, rgba(27, 34, 40, 0.72) 70%, rgba(27, 34, 40, 0.88) 100%),
    var(--hero-image) center / cover no-repeat;
  transform: scale(1.04);
  animation: heroDrift 18s var(--ease) infinite alternate;
  z-index: 0;
}

.hero-content {
  position: relative;
  z-index: 1;
  width: min(100% - 2rem, var(--max));
  margin: 0 auto 4.5rem;
  max-width: 38rem;
  animation: riseIn 0.9s var(--ease) both;
}

.hero-brand {
  font-family: var(--font-display);
  font-size: clamp(2.8rem, 8vw, 5.2rem);
  font-weight: 700;
  letter-spacing: -0.04em;
  margin: 0 0 0.6rem;
  line-height: 1;
}

.hero-content h1 {
  color: #fff;
  font-size: clamp(1.35rem, 3vw, 1.85rem);
  font-weight: 500;
  margin: 0 0 0.85rem;
}

.hero-content p {
  color: rgba(255, 255, 255, 0.88);
  font-size: 1.05rem;
  margin-bottom: 1.4rem;
}

.page-hero {
  padding: 3.5rem 0 2.5rem;
  border-bottom: 1px solid var(--line);
  background:
    linear-gradient(120deg, rgba(220, 233, 232, 0.7), transparent 55%),
    linear-gradient(0deg, transparent, rgba(255, 255, 255, 0.4));
}

.page-hero h1 {
  font-size: clamp(1.9rem, 4vw, 2.7rem);
  margin: 0 0 0.7rem;
}

.page-hero p {
  color: var(--ink-soft);
  max-width: 40rem;
  margin: 0;
}

.page-hero-media {
  margin-top: 1.75rem;
  border-radius: 0;
  overflow: hidden;
  min-height: 240px;
  background: var(--bg-deep) center / cover no-repeat;
  animation: fadeLift 1s var(--ease) both;
}

/* Sections */
.section {
  padding: 4.25rem 0;
}

.section-alt {
  background: rgba(255, 255, 255, 0.55);
  border-block: 1px solid rgba(213, 220, 226, 0.65);
}

.section-head {
  margin-bottom: 2rem;
  max-width: 38rem;
}

.section-head h2 {
  font-size: clamp(1.55rem, 3vw, 2.1rem);
  margin: 0 0 0.55rem;
}

.section-head p {
  color: var(--ink-soft);
  margin: 0;
}

.eyebrow {
  display: inline-block;
  font-size: 0.78rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--accent);
  font-weight: 600;
  margin-bottom: 0.55rem;
}

/* Proof strip */
.proof-strip {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1rem;
  padding: 1.5rem 0;
}

.proof-item {
  text-align: center;
  padding: 1rem;
}

.proof-item strong {
  display: block;
  font-family: var(--font-display);
  font-size: clamp(1.6rem, 3vw, 2.1rem);
  color: var(--accent);
  letter-spacing: -0.03em;
}

.proof-item span {
  color: var(--ink-soft);
  font-size: 0.92rem;
}

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

/* Feature list */
.feature-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
}

.feature-item {
  padding: 0.25rem 0;
  border-top: 2px solid var(--accent-soft);
  padding-top: 1.1rem;
  animation: riseIn 0.7s var(--ease) both;
}

.feature-item:nth-child(2) { animation-delay: 0.08s; }
.feature-item:nth-child(3) { animation-delay: 0.16s; }

.feature-item h3 {
  margin: 0 0 0.5rem;
  font-size: 1.2rem;
}

.feature-item p {
  color: var(--ink-soft);
  margin: 0;
  font-size: 0.98rem;
}

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

/* Course / blog listing */
.item-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 1.5rem;
}

.item-link {
  display: block;
  text-decoration: none;
  color: inherit;
  transition: transform 0.3s var(--ease);
}

.item-link:hover { transform: translateY(-3px); }

.item-media {
  aspect-ratio: 16 / 10;
  background: var(--bg-deep) center / cover no-repeat;
  margin-bottom: 0.9rem;
}

.item-link h3 {
  margin: 0 0 0.4rem;
  font-size: 1.2rem;
}

.item-link p {
  color: var(--ink-soft);
  margin: 0;
  font-size: 0.95rem;
}

.meta {
  color: var(--ink-soft);
  font-size: 0.85rem;
  margin-bottom: 0.35rem;
}

/* Testimonials */
.quote-stack {
  display: grid;
  gap: 1.75rem;
}

.quote {
  border-left: 3px solid var(--accent-mist);
  padding: 0.2rem 0 0.2rem 1.2rem;
}

.quote p {
  font-size: 1.05rem;
  margin-bottom: 0.65rem;
}

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

.quote-long {
  background: rgba(255, 255, 255, 0.7);
  border: 1px solid var(--line);
  border-left: 3px solid var(--accent);
  padding: 1.4rem 1.5rem;
}

/* Pricing */
.price-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.25rem;
  align-items: stretch;
}

.price-tier {
  background: var(--surface);
  border: 1px solid var(--line);
  padding: 1.6rem 1.4rem 1.5rem;
  display: flex;
  flex-direction: column;
  gap: 0.85rem;
}

.price-tier.featured {
  border-color: var(--accent);
  box-shadow: var(--shadow);
  transform: translateY(-4px);
}

.price-tier h3 {
  margin: 0;
  font-size: 1.35rem;
}

.price-amount {
  font-family: var(--font-display);
  font-size: 2rem;
  letter-spacing: -0.03em;
  margin: 0;
}

.price-tier ul {
  margin: 0;
  color: var(--ink-soft);
  flex: 1;
}

.price-tier .btn { align-self: flex-start; }

@media (max-width: 900px) {
  .price-grid { grid-template-columns: 1fr; }
  .price-tier.featured { transform: none; }
}

/* Forms */
.form {
  display: grid;
  gap: 1rem;
  background: var(--surface);
  border: 1px solid var(--line);
  padding: 1.5rem;
}

.form-row {
  display: grid;
  gap: 0.35rem;
}

.form label {
  font-weight: 560;
  font-size: 0.92rem;
}

.form input,
.form select,
.form textarea {
  font: inherit;
  padding: 0.7rem 0.85rem;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
  color: var(--ink);
}

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

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

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

.form-status {
  padding: 0.75rem 0.9rem;
  border-radius: 8px;
  display: none;
}

.form-status.is-success {
  display: block;
  background: var(--accent-soft);
  color: var(--accent-hover);
}

.form-status.is-error {
  display: block;
  background: #f6e8e2;
  color: var(--warn);
}

.contact-layout {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 2rem;
  align-items: start;
}

.contact-aside {
  background: rgba(255, 255, 255, 0.65);
  border: 1px solid var(--line);
  padding: 1.4rem;
}

.contact-aside h2 {
  margin-top: 0;
  font-size: 1.2rem;
}

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

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

/* Legal */
.legal-content h2 {
  margin-top: 2rem;
  font-size: 1.35rem;
}

.legal-content table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.92rem;
  margin: 1rem 0 1.5rem;
}

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

.legal-content th {
  background: rgba(220, 233, 232, 0.55);
}

/* Modules / FAQ */
.module-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: grid;
  gap: 0.85rem;
}

.module-list li {
  padding: 1rem 0;
  border-bottom: 1px solid var(--line);
}

.module-list h3 {
  margin: 0 0 0.35rem;
  font-size: 1.1rem;
}

.module-list p {
  margin: 0;
  color: var(--ink-soft);
  font-size: 0.95rem;
}

.faq-list details {
  border-bottom: 1px solid var(--line);
  padding: 0.9rem 0;
}

.faq-list summary {
  cursor: pointer;
  font-weight: 600;
}

.faq-list details p {
  margin: 0.6rem 0 0;
  color: var(--ink-soft);
}

.two-col {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 2rem;
  align-items: start;
}

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

.instructor {
  display: grid;
  grid-template-columns: 96px 1fr;
  gap: 1rem;
  align-items: center;
}

.instructor img {
  width: 96px;
  height: 96px;
  object-fit: cover;
  border-radius: 50%;
}

.prose h2 {
  margin-top: 2.2rem;
  font-size: 1.45rem;
}

.prose h3 {
  margin-top: 1.5rem;
  font-size: 1.15rem;
}

.prose p,
.prose li {
  color: var(--ink-soft);
}

.article-cover {
  aspect-ratio: 21 / 9;
  background: var(--bg-deep) center / cover no-repeat;
  margin: 1.5rem 0 2rem;
}

/* CTA band */
.cta-band {
  padding: 3.5rem 0;
  text-align: center;
  background:
    linear-gradient(135deg, rgba(47, 93, 98, 0.92), rgba(36, 74, 78, 0.95)),
    var(--bg-deep);
  color: #fff;
}

.cta-band h2 {
  color: #fff;
  margin: 0 0 0.6rem;
  font-size: clamp(1.5rem, 3vw, 2rem);
}

.cta-band p {
  color: rgba(255, 255, 255, 0.88);
  max-width: 32rem;
  margin: 0 auto 1.3rem;
}

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

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

/* Footer */
.site-footer {
  background: #1b2228;
  color: rgba(255, 255, 255, 0.78);
  padding: 3rem 0 1.5rem;
  margin-top: 2rem;
}

.footer-inner {
  width: min(100% - 2rem, var(--max));
  margin-inline: auto;
}

.logo-footer .logo-text { color: #fff; }

.footer-tagline {
  color: rgba(255, 255, 255, 0.62);
  max-width: 22rem;
  font-size: 0.95rem;
}

.footer-cols {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1.5rem;
  margin: 2rem 0;
}

.footer-heading {
  color: #fff;
  font-size: 0.95rem;
  margin: 0 0 0.75rem;
}

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

.footer-col li { margin-bottom: 0.4rem; }

.footer-col a {
  color: rgba(255, 255, 255, 0.7);
  text-decoration: none;
  font-size: 0.92rem;
}

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

.footer-contact p {
  font-size: 0.88rem;
  margin-bottom: 0.55rem;
  color: rgba(255, 255, 255, 0.68);
}

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.12);
  padding-top: 1rem;
  font-size: 0.85rem;
  color: rgba(255, 255, 255, 0.5);
}

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

@media (max-width: 520px) {
  .footer-cols { grid-template-columns: 1fr; }
}

/* Cookie banner */
.cookie-banner {
  position: fixed;
  left: 1rem;
  right: 1rem;
  bottom: 1rem;
  z-index: 200;
  max-width: 560px;
  margin-inline: auto;
  background: var(--surface);
  border: 1px solid var(--line);
  box-shadow: var(--shadow);
  padding: 1.15rem 1.2rem;
  border-radius: var(--radius);
  display: none;
}

.cookie-banner.is-visible { display: block; animation: riseIn 0.4s var(--ease); }

.cookie-banner p {
  margin: 0 0 0.9rem;
  font-size: 0.92rem;
  color: var(--ink-soft);
}

.cookie-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.55rem;
}

/* 404 */
.error-page {
  min-height: 60vh;
  display: grid;
  place-items: center;
  text-align: center;
  padding: 4rem 1rem;
}

.error-page h1 {
  font-size: clamp(3rem, 10vw, 5.5rem);
  margin: 0;
  color: var(--accent);
}

/* Inline script errors */
.runtime-error {
  background: #f6e8e2;
  color: var(--warn);
  padding: 0.75rem 1rem;
  margin: 0.5rem 0;
  border-radius: 8px;
  font-size: 0.9rem;
}

@keyframes riseIn {
  from { opacity: 0; transform: translateY(14px); }
  to { opacity: 1; transform: translateY(0); }
}

@keyframes fadeLift {
  from { opacity: 0; transform: translateY(10px) scale(1.01); }
  to { opacity: 1; transform: translateY(0) scale(1); }
}

@keyframes heroDrift {
  from { transform: scale(1.04) translate3d(0, 0, 0); }
  to { transform: scale(1.08) translate3d(-1.2%, -0.8%, 0); }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation: none !important;
    transition: none !important;
  }
  html { scroll-behavior: auto; }
}