/* Hepilev — Signal Lab theme
   Ink slate + copper accent on cool mist grids. Single theme, no toggle. */

@import url("https://fonts.googleapis.com/css2?family=Hahmlet:wght@500;700;800&family=IBM+Plex+Sans+KR:wght@400;500;600;700&display=swap");

:root {
  --ink: #132129;
  --ink-soft: #2a3d47;
  --mist: #d7e3ea;
  --fog: #eef4f7;
  --paper: #f6fafb;
  --line: rgba(19, 33, 41, 0.12);
  --copper: #c45c26;
  --copper-deep: #9a4318;
  --teal: #1f7a6b;
  --teal-soft: #d5ebe6;
  --warn: #a33b2c;
  --ok: #1b6b4a;
  --shadow: 0 18px 48px rgba(19, 33, 41, 0.12);
  --radius: 4px;
  --font-display: "Hahmlet", "Apple SD Gothic Neo", serif;
  --font-body: "IBM Plex Sans KR", "Apple SD Gothic Neo", 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);
  color: var(--ink);
  background:
    radial-gradient(1200px 600px at 10% -10%, rgba(31, 122, 107, 0.14), transparent 55%),
    radial-gradient(900px 500px at 90% 0%, rgba(196, 92, 38, 0.1), transparent 50%),
    linear-gradient(180deg, var(--fog) 0%, var(--paper) 40%, var(--mist) 100%);
  background-attachment: fixed;
  line-height: 1.65;
  min-height: 100vh;
}

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

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

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

h1,
h2,
h3,
h4 {
  font-family: var(--font-display);
  line-height: 1.25;
  letter-spacing: -0.02em;
  margin: 0 0 0.6em;
  font-weight: 700;
}

p {
  margin: 0 0 1rem;
}

ul,
ol {
  margin: 0 0 1rem;
  padding-left: 1.2rem;
}

.skip-link {
  position: absolute;
  left: -9999px;
  top: 0;
  background: var(--ink);
  color: #fff;
  padding: 0.75rem 1rem;
  z-index: 1000;
}

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

.inline-error {
  background: #f8e4e0;
  color: var(--warn);
  padding: 0.85rem 1.25rem;
  border-bottom: 2px solid var(--warn);
  font-size: 0.95rem;
}

/* Header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: blur(12px);
  background: rgba(246, 250, 251, 0.88);
  border-bottom: 1px solid var(--line);
}

.header-inner {
  max-width: var(--max);
  margin: 0 auto;
  padding: 0.85rem 1.25rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  min-height: var(--header-h);
}

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

.brand-mark {
  width: 28px;
  height: 28px;
  background:
    linear-gradient(135deg, var(--teal) 0%, var(--teal) 45%, transparent 45%),
    linear-gradient(315deg, var(--copper) 0%, var(--copper) 45%, transparent 45%);
  clip-path: polygon(50% 0%, 100% 25%, 100% 75%, 50% 100%, 0% 75%, 0% 25%);
  animation: pulse-mark 4.5s var(--ease) infinite;
}

@keyframes pulse-mark {
  0%,
  100% {
    transform: scale(1);
  }
  50% {
    transform: scale(1.06);
  }
}

.brand-name {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 1.35rem;
  letter-spacing: -0.03em;
}

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

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

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

.nav-toggle {
  display: none;
  width: 44px;
  height: 44px;
  border: 1px solid var(--line);
  background: var(--paper);
  border-radius: var(--radius);
  cursor: pointer;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 5px;
  padding: 0;
}

.nav-toggle span {
  display: block;
  width: 18px;
  height: 2px;
  background: var(--ink);
}

@media (max-width: 860px) {
  .nav-toggle {
    display: flex;
  }

  .site-nav {
    position: absolute;
    left: 0;
    right: 0;
    top: 100%;
    background: var(--paper);
    border-bottom: 1px solid var(--line);
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.35s var(--ease);
  }

  .site-nav.is-open {
    max-height: 420px;
  }

  .site-nav ul {
    flex-direction: column;
    padding: 0.75rem 1.25rem 1.25rem;
    gap: 0.75rem;
  }
}

/* Layout */
.wrap {
  max-width: var(--max);
  margin: 0 auto;
  padding: 0 1.25rem;
}

.section {
  padding: 4.5rem 0;
}

.section-tight {
  padding: 3rem 0;
}

.eyebrow {
  display: inline-block;
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--teal);
  margin-bottom: 0.75rem;
}

.lede {
  font-size: 1.1rem;
  color: var(--ink-soft);
  max-width: 38rem;
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.4rem;
  padding: 0.85rem 1.4rem;
  border-radius: var(--radius);
  font-family: var(--font-body);
  font-weight: 600;
  font-size: 0.95rem;
  border: 2px solid transparent;
  cursor: pointer;
  text-decoration: none;
  transition: transform 0.2s var(--ease), background 0.2s, color 0.2s, border-color 0.2s;
}

.btn:hover {
  transform: translateY(-2px);
}

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

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

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

.btn-ghost:hover {
  background: var(--ink);
  color: #fff;
}

.btn-teal {
  background: var(--teal);
  color: #fff;
  border-color: var(--teal);
}

.btn-teal:hover {
  background: #165a4f;
  color: #fff;
}

.cta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-top: 1.5rem;
}

/* Hero — full-bleed brand plane */
.hero-bleed {
  position: relative;
  min-height: calc(100vh - var(--header-h));
  display: grid;
  align-items: end;
  overflow: hidden;
  color: #fff;
}

.hero-bleed::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image: url("https://images.unsplash.com/photo-1551288049-bebda4e38f71?auto=format&fit=crop&w=1920&q=80");
  background-size: cover;
  background-position: center;
  transform: scale(1.04);
  animation: hero-drift 18s ease-in-out infinite alternate;
}

@keyframes hero-drift {
  from {
    transform: scale(1.04) translate3d(0, 0, 0);
  }
  to {
    transform: scale(1.1) translate3d(-1.5%, -1%, 0);
  }
}

.hero-bleed::after {
  content: "";
  position: absolute;
  inset: 0;
  background:
    linear-gradient(105deg, rgba(19, 33, 41, 0.92) 0%, rgba(19, 33, 41, 0.72) 42%, rgba(31, 122, 107, 0.35) 100%),
    repeating-linear-gradient(
      -18deg,
      transparent,
      transparent 22px,
      rgba(255, 255, 255, 0.03) 22px,
      rgba(255, 255, 255, 0.03) 23px
    );
}

.hero-content {
  position: relative;
  z-index: 1;
  max-width: var(--max);
  margin: 0 auto;
  padding: 4rem 1.25rem 5rem;
  width: 100%;
}

.hero-brand {
  font-family: var(--font-display);
  font-size: clamp(3.2rem, 10vw, 6.5rem);
  font-weight: 800;
  letter-spacing: -0.04em;
  line-height: 0.95;
  margin: 0 0 1.25rem;
  animation: brand-rise 0.9s var(--ease) both;
}

.hero-line {
  font-size: clamp(1.15rem, 2.4vw, 1.55rem);
  max-width: 28rem;
  font-weight: 500;
  margin: 0;
  opacity: 0.95;
  animation: brand-rise 0.9s 0.15s var(--ease) both;
}

.hero-actions {
  animation: brand-rise 0.9s 0.28s var(--ease) both;
}

@keyframes brand-rise {
  from {
    opacity: 0;
    transform: translateY(28px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.page-hero {
  position: relative;
  padding: 4rem 0 3rem;
  overflow: hidden;
}

.page-hero .wrap {
  position: relative;
  z-index: 1;
}

.page-hero h1 {
  font-size: clamp(2rem, 5vw, 3.1rem);
  max-width: 16ch;
}

.page-hero--media {
  min-height: 42vh;
  display: flex;
  align-items: flex-end;
  color: #fff;
  padding: 0;
}

.page-hero--media::before {
  content: "";
  position: absolute;
  inset: 0;
  background-size: cover;
  background-position: center;
}

.page-hero--media::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(19, 33, 41, 0.25), rgba(19, 33, 41, 0.88));
}

.page-hero--media .wrap {
  padding-top: 6rem;
  padding-bottom: 2.5rem;
}

.page-hero--media h1,
.page-hero--media .lede {
  color: #fff;
}

.page-hero--media .lede {
  opacity: 0.9;
}

.hero-bg-courses::before {
  background-image: url("https://images.unsplash.com/photo-1516321318423-f06f85e504b3?auto=format&fit=crop&w=1600&q=80");
}

.hero-bg-flagship::before {
  background-image: url("https://images.unsplash.com/photo-1504868584819-f8e8b4b6d7e3?auto=format&fit=crop&w=1600&q=80");
}

.hero-bg-guide::before {
  background-image: url("https://images.unsplash.com/photo-1563986768609-322da13575f3?auto=format&fit=crop&w=1600&q=80");
}

/* Split proof band */
.proof-band {
  background: var(--ink);
  color: #e8f0f3;
  padding: 2.25rem 0;
}

.proof-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
  text-align: left;
}

.proof-grid strong {
  display: block;
  font-family: var(--font-display);
  font-size: clamp(1.8rem, 4vw, 2.4rem);
  color: #fff;
  letter-spacing: -0.03em;
}

.proof-grid span {
  font-size: 0.95rem;
  opacity: 0.8;
}

@media (max-width: 700px) {
  .proof-grid {
    grid-template-columns: 1fr;
    gap: 1.25rem;
  }
}

/* Course / content lists — no card chrome by default */
.course-rail {
  display: grid;
  gap: 2.5rem;
}

.course-item {
  display: grid;
  grid-template-columns: minmax(0, 1.1fr) minmax(0, 1.2fr);
  gap: 1.75rem;
  align-items: center;
  padding-bottom: 2.5rem;
  border-bottom: 1px solid var(--line);
}

.course-item:last-child {
  border-bottom: 0;
  padding-bottom: 0;
}

.course-item img {
  width: 100%;
  aspect-ratio: 16 / 10;
  object-fit: cover;
  filter: saturate(0.92) contrast(1.05);
}

.course-item h3 {
  font-size: 1.45rem;
  margin-bottom: 0.4rem;
}

.course-meta {
  font-size: 0.88rem;
  color: var(--ink-soft);
  margin-bottom: 0.75rem;
}

@media (max-width: 760px) {
  .course-item {
    grid-template-columns: 1fr;
  }
}

.benefit-list {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 2rem 2.5rem;
  list-style: none;
  padding: 0;
  margin: 0;
}

.benefit-list li {
  padding-left: 0;
  border-top: 2px solid var(--teal);
  padding-top: 1rem;
}

.benefit-list h3 {
  font-size: 1.2rem;
}

@media (max-width: 640px) {
  .benefit-list {
    grid-template-columns: 1fr;
  }
}

/* Quotes */
.quote-stack {
  display: grid;
  gap: 2rem;
}

.quote {
  border-left: 3px solid var(--copper);
  padding: 0.25rem 0 0.25rem 1.25rem;
}

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

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

.stars {
  color: var(--copper);
  letter-spacing: 0.08em;
  font-size: 0.85rem;
  margin-bottom: 0.35rem;
}

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

.tier {
  padding: 1.75rem 1.5rem;
  border-top: 3px solid var(--ink);
  background: rgba(255, 255, 255, 0.45);
}

.tier.featured {
  border-top-color: var(--copper);
  background: rgba(255, 255, 255, 0.7);
}

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

.tier .price {
  font-family: var(--font-display);
  font-size: 2rem;
  font-weight: 700;
  margin: 0.5rem 0 1rem;
}

.tier ul {
  padding-left: 1.1rem;
  margin-bottom: 1.5rem;
  color: var(--ink-soft);
}

@media (max-width: 860px) {
  .price-tiers {
    grid-template-columns: 1fr;
  }
}

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

.form-field label {
  display: block;
  font-weight: 600;
  margin-bottom: 0.35rem;
  font-size: 0.92rem;
}

.form-field input,
.form-field textarea,
.form-field select {
  width: 100%;
  padding: 0.8rem 0.9rem;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  font: inherit;
  background: #fff;
  color: var(--ink);
}

.form-field input:focus,
.form-field textarea:focus,
.form-field select:focus {
  outline: 2px solid var(--teal);
  outline-offset: 1px;
}

.form-field input[aria-invalid="true"],
.form-field textarea[aria-invalid="true"] {
  border-color: var(--warn);
}

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

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

.form-status.is-success,
.form-status.is-error {
  display: block;
}

.form-status.is-success {
  background: var(--teal-soft);
  color: var(--ok);
}

.form-status.is-error {
  background: #f8e4e0;
  color: var(--warn);
}

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

.contact-aside {
  padding-top: 0.5rem;
}

.contact-aside address {
  font-style: normal;
  margin-bottom: 1rem;
  line-height: 1.7;
}

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

/* Blog */
.blog-list {
  display: grid;
  gap: 2.25rem;
}

.blog-row {
  display: grid;
  grid-template-columns: 220px 1fr;
  gap: 1.5rem;
  align-items: start;
  padding-bottom: 2rem;
  border-bottom: 1px solid var(--line);
}

.blog-row img {
  width: 100%;
  aspect-ratio: 4 / 3;
  object-fit: cover;
}

.blog-row h2 {
  font-size: 1.35rem;
  margin-bottom: 0.35rem;
}

.blog-row h2 a {
  color: var(--ink);
  text-decoration: none;
}

.blog-row h2 a:hover {
  color: var(--copper-deep);
}

.blog-meta {
  font-size: 0.85rem;
  color: var(--ink-soft);
  margin-bottom: 0.5rem;
}

@media (max-width: 640px) {
  .blog-row {
    grid-template-columns: 1fr;
  }
}

.article {
  max-width: 42rem;
  margin: 0 auto;
  padding: 3rem 1.25rem 4rem;
}

.article h1 {
  font-size: clamp(1.8rem, 4vw, 2.6rem);
}

.article .article-meta {
  color: var(--ink-soft);
  font-size: 0.9rem;
  margin-bottom: 2rem;
}

.article-cover {
  width: 100%;
  max-height: 420px;
  object-fit: cover;
  margin-bottom: 2rem;
}

.prose h2 {
  margin-top: 2rem;
  font-size: 1.4rem;
}

.prose table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.9rem;
  margin: 1.25rem 0;
}

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

.prose th {
  background: rgba(31, 122, 107, 0.08);
}

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

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

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

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

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

.module-list li {
  counter-increment: mod;
  padding: 1.1rem 0 1.1rem 3rem;
  border-bottom: 1px solid var(--line);
  position: relative;
}

.module-list li::before {
  content: counter(mod, decimal-leading-zero);
  position: absolute;
  left: 0;
  top: 1.1rem;
  font-family: var(--font-display);
  font-weight: 700;
  color: var(--teal);
}

/* Footer */
.site-footer {
  background: var(--ink);
  color: #c5d4db;
  padding: 3.5rem 0 2rem;
  margin-top: 3rem;
}

.footer-inner {
  max-width: var(--max);
  margin: 0 auto;
  padding: 0 1.25rem;
}

.footer-logo {
  font-family: var(--font-display);
  font-size: 1.5rem;
  font-weight: 800;
  color: #fff;
  margin: 0 0 0.4rem;
}

.footer-tag {
  max-width: 28rem;
  margin-bottom: 2rem;
  opacity: 0.85;
}

.footer-cols {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1.75rem;
  margin-bottom: 2.5rem;
}

.footer-cols h2 {
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: #fff;
  margin-bottom: 0.85rem;
  font-family: var(--font-body);
  font-weight: 600;
}

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

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

.footer-cols a {
  color: #c5d4db;
  text-decoration: none;
}

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

.footer-cols address {
  font-style: normal;
  font-size: 0.9rem;
  line-height: 1.65;
}

.footer-copy {
  border-top: 1px solid rgba(255, 255, 255, 0.12);
  padding-top: 1.25rem;
  font-size: 0.85rem;
  opacity: 0.7;
  margin: 0;
}

@media (max-width: 860px) {
  .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: 640px;
  margin: 0 auto;
  background: var(--paper);
  border: 1px solid var(--line);
  box-shadow: var(--shadow);
  border-radius: var(--radius);
}

.cookie-banner-inner {
  padding: 1.15rem 1.25rem;
  display: grid;
  gap: 1rem;
}

.cookie-banner-inner p {
  margin: 0;
  font-size: 0.92rem;
}

.cookie-banner-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
  justify-content: flex-end;
}

/* Reveal motion */
.reveal {
  opacity: 0;
  transform: translateY(22px);
  transition: opacity 0.7s var(--ease), transform 0.7s var(--ease);
}

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

.two-col {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 2.5rem;
  align-items: start;
}

@media (max-width: 760px) {
  .two-col {
    grid-template-columns: 1fr;
  }
}

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

.instructor {
  display: flex;
  gap: 1.25rem;
  align-items: center;
}

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

.case-study h3 {
  font-size: 1.35rem;
}

.muted {
  color: var(--ink-soft);
}

.legal .prose {
  max-width: 48rem;
}

.center-404 {
  min-height: 60vh;
  display: grid;
  place-content: center;
  text-align: center;
  padding: 3rem 1.25rem;
}

.center-404 h1 {
  font-size: clamp(3rem, 12vw, 6rem);
  margin-bottom: 0.25rem;
}

.tag-list {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem 1rem;
  list-style: none;
  padding: 0;
  margin: 1rem 0 0;
  font-size: 0.9rem;
  color: var(--ink-soft);
}

.tag-list li::before {
  content: "· ";
  color: var(--copper);
}

.section-head {
  margin-bottom: 2.25rem;
  max-width: 36rem;
}

.section-head h2 {
  font-size: clamp(1.6rem, 3.5vw, 2.2rem);
}