:root {
  --ink: #121937;
  --paper: #f6f7fb;
  --white: #ffffff;
  --electric: #5b5ff2;
  --acid: #f1ff4e;
  --cyan: #bdeffc;
  --muted: #686d80;
  --line: #cfd2df;
  --shadow: 0 18px 55px rgba(18, 25, 55, 0.12);
  font-family: Pretendard, "Noto Sans KR", "Apple SD Gothic Neo", Inter, system-ui, sans-serif;
  color: var(--ink);
  background: var(--paper);
  font-synthesis: none;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  min-width: 320px;
  background:
    linear-gradient(rgba(18, 25, 55, 0.035) 1px, transparent 1px),
    linear-gradient(90deg, rgba(18, 25, 55, 0.035) 1px, transparent 1px),
    var(--paper);
  background-size: 36px 36px;
  font-size: 1rem;
  line-height: 1.65;
}

a {
  color: inherit;
  text-decoration: none;
}

button,
input {
  font: inherit;
}

button,
a {
  -webkit-tap-highlight-color: transparent;
}

:focus-visible {
  outline: 3px solid var(--electric);
  outline-offset: 4px;
}

.skip-link {
  position: fixed;
  z-index: 100;
  top: 1rem;
  left: 1rem;
  padding: 0.75rem 1rem;
  transform: translateY(-180%);
  border: 2px solid var(--ink);
  background: var(--acid);
  font-weight: 800;
}

.skip-link:focus {
  transform: translateY(0);
}

.site-header {
  position: sticky;
  z-index: 50;
  top: 0;
  display: flex;
  min-height: 76px;
  align-items: center;
  justify-content: space-between;
  padding: 0 4vw;
  border-bottom: 1px solid rgba(18, 25, 55, 0.18);
  background: rgba(246, 247, 251, 0.92);
  backdrop-filter: blur(18px);
}

.brand,
.footer-brand {
  display: inline-flex;
  align-items: center;
  gap: 0.75rem;
  font-weight: 900;
  letter-spacing: -0.035em;
}

.brand-mark {
  display: grid;
  width: 2.25rem;
  height: 2.25rem;
  place-items: center;
  border-radius: 0.65rem;
  color: var(--acid);
  background: var(--ink);
  font-family: serif;
  font-size: 1.15rem;
}

.main-nav {
  display: flex;
  align-items: center;
  gap: clamp(1rem, 3vw, 2.5rem);
  font-size: 0.9rem;
  font-weight: 700;
}

.main-nav a {
  position: relative;
}

.main-nav a::after {
  position: absolute;
  right: 0;
  bottom: -0.25rem;
  left: 0;
  height: 2px;
  content: "";
  transform: scaleX(0);
  transform-origin: right;
  background: var(--electric);
  transition: transform 180ms ease;
}

.main-nav a:hover::after {
  transform: scaleX(1);
  transform-origin: left;
}

main,
footer {
  width: min(1440px, 100%);
  margin: 0 auto;
}

.intro {
  display: grid;
  min-height: calc(100vh - 76px);
  grid-template-columns: minmax(0, 1.3fr) minmax(300px, 0.7fr);
  border-bottom: 1px solid var(--line);
}

.intro-copy {
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding: clamp(4rem, 9vw, 9rem) clamp(1.5rem, 7vw, 7rem);
  border-right: 1px solid var(--line);
}

.eyebrow,
.section-number {
  margin: 0;
  color: var(--electric);
  font-size: 0.78rem;
  font-weight: 900;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

.eyebrow {
  display: flex;
  max-width: 46rem;
  justify-content: space-between;
  padding-bottom: 0.85rem;
  border-bottom: 1px solid var(--line);
}

h1,
h2,
h3,
p {
  text-wrap: pretty;
}

h1 {
  max-width: 58rem;
  margin: 2.25rem 0 1.6rem;
  font-size: clamp(3.4rem, 7.5vw, 7.8rem);
  font-weight: 950;
  line-height: 0.98;
  letter-spacing: -0.075em;
}

.intro-text {
  max-width: 38rem;
  margin: 0;
  color: #444a61;
  font-size: clamp(1.05rem, 1.6vw, 1.3rem);
  word-break: keep-all;
}

.primary-link {
  display: inline-flex;
  width: fit-content;
  min-width: 13rem;
  align-items: center;
  justify-content: space-between;
  gap: 2rem;
  margin-top: 2.75rem;
  padding: 1rem 1.2rem;
  border: 2px solid var(--ink);
  border-radius: 999px;
  background: var(--acid);
  box-shadow: 5px 5px 0 var(--ink);
  font-weight: 900;
  transition: transform 180ms ease, box-shadow 180ms ease;
}

.primary-link:hover {
  transform: translate(3px, 3px);
  box-shadow: 2px 2px 0 var(--ink);
}

.intro-index {
  display: flex;
  flex-direction: column;
  justify-content: flex-end;
  overflow: hidden;
  background: var(--ink);
  color: var(--white);
}

.index-heading {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  padding: 2rem;
  color: var(--cyan);
  font-size: 0.75rem;
  letter-spacing: 0.14em;
}

.index-heading strong {
  font-size: 1rem;
}

.intro-index ol {
  margin: 0;
  padding: 0;
  list-style: none;
}

.intro-index li {
  border-top: 1px solid rgba(255, 255, 255, 0.18);
}

.intro-index li:nth-child(2) {
  background: var(--electric);
}

.intro-index a {
  display: grid;
  grid-template-columns: 3rem 1fr auto;
  align-items: center;
  gap: 1rem;
  padding: clamp(1.5rem, 4vw, 2.8rem) 2rem;
  transition: padding-left 180ms ease, background 180ms ease;
}

.intro-index a:hover {
  padding-left: 2.8rem;
  background: rgba(255, 255, 255, 0.08);
}

.intro-index a > span {
  color: var(--cyan);
  font-size: 0.78rem;
  font-weight: 800;
}

.intro-index a strong {
  font-size: clamp(1.35rem, 2.3vw, 2rem);
  letter-spacing: -0.045em;
}

.intro-index a small {
  color: rgba(255, 255, 255, 0.62);
  font-size: 0.68rem;
  letter-spacing: 0.12em;
}

.resource-section,
.guide-section {
  padding: clamp(5rem, 9vw, 9rem) clamp(1.5rem, 5vw, 5rem);
}

.section-heading {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 2rem;
  padding-bottom: 2rem;
  border-bottom: 1px solid var(--line);
}

.section-heading h2,
.submission-copy h2 {
  margin: 0.4rem 0 0;
  font-size: clamp(2.6rem, 5vw, 5rem);
  line-height: 1;
  letter-spacing: -0.065em;
}

.section-heading > p {
  max-width: 28rem;
  margin: 0;
  color: var(--muted);
}

.resource-tools {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 2rem 0;
}

.search-box {
  display: flex;
  width: min(100%, 28rem);
  align-items: center;
  gap: 0.8rem;
  padding: 0 1rem;
  border: 1px solid var(--ink);
  border-radius: 999px;
  background: var(--white);
}

.search-box:focus-within {
  box-shadow: 0 0 0 3px rgba(91, 95, 242, 0.25);
}

.search-box svg {
  width: 1.25rem;
  fill: none;
  stroke: currentColor;
  stroke-linecap: round;
  stroke-width: 1.8;
}

.search-box input {
  width: 100%;
  min-height: 3.1rem;
  border: 0;
  outline: 0;
  background: transparent;
  color: var(--ink);
  font-size: 1rem;
}

.filters {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 0.5rem;
}

.filter-button,
#reset-search {
  min-height: 2.75rem;
  padding: 0.55rem 1rem;
  border: 1px solid var(--ink);
  border-radius: 999px;
  background: transparent;
  color: var(--ink);
  cursor: pointer;
  font-size: 0.9rem;
  font-weight: 800;
}

.filter-button:hover,
.filter-button.is-active,
#reset-search:hover {
  background: var(--ink);
  color: var(--white);
}

.resource-meta {
  display: flex;
  justify-content: space-between;
  padding: 0 0 1rem;
  color: var(--muted);
  font-size: 0.85rem;
  font-weight: 700;
}

.resource-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1rem;
}

.resource-card {
  display: flex;
  min-height: 24rem;
  flex-direction: column;
  justify-content: space-between;
  padding: 1.5rem;
  border: 1px solid var(--line);
  background: var(--white);
  transition: transform 180ms ease, box-shadow 180ms ease;
}

.resource-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow);
}

.card-featured {
  background: var(--cyan);
}

.card-accent {
  background: var(--acid);
}

.card-dark {
  border-color: var(--ink);
  background: var(--ink);
  color: var(--white);
}

.card-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  font-size: 0.75rem;
  font-weight: 900;
  letter-spacing: 0.08em;
}

.type-label {
  padding: 0.35rem 0.55rem;
  border: 1px solid currentColor;
  border-radius: 999px;
}

.card-number {
  opacity: 0.58;
}

.card-body {
  margin-top: auto;
  padding: 4rem 0 2rem;
}

.course-name {
  margin: 0 0 0.4rem;
  color: var(--electric);
  font-size: 0.82rem;
  font-weight: 900;
}

.card-dark .course-name {
  color: var(--acid);
}

.card-body h3 {
  margin: 0 0 0.8rem;
  font-size: clamp(1.5rem, 2.4vw, 2rem);
  line-height: 1.15;
  letter-spacing: -0.045em;
}

.card-body p:last-child {
  margin: 0;
  color: var(--muted);
  font-size: 0.93rem;
}

.card-dark .card-body p:last-child {
  color: rgba(255, 255, 255, 0.66);
}

.card-action {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: 1rem;
  border-top: 1px solid currentColor;
  font-size: 0.9rem;
  font-weight: 900;
}

.card-action.is-pending {
  opacity: 0.55;
}

.empty-state {
  padding: 5rem 1rem;
  border: 1px dashed var(--line);
  background: var(--white);
  text-align: center;
}

.empty-state strong {
  display: block;
  font-size: 1.5rem;
}

.empty-state p {
  margin: 0.5rem 0 1.5rem;
  color: var(--muted);
}

.submission-section {
  display: grid;
  grid-template-columns: minmax(0, 0.85fr) minmax(320px, 1.15fr);
  gap: clamp(2rem, 7vw, 7rem);
  padding: clamp(5rem, 9vw, 9rem) clamp(1.5rem, 7vw, 7rem);
  background: var(--electric);
  color: var(--white);
}

.submission-copy > p:last-child {
  max-width: 33rem;
  margin-top: 1.75rem;
  color: rgba(255, 255, 255, 0.72);
}

.submission-section .section-number {
  color: var(--acid);
}

.submission-panel {
  align-self: center;
  padding: clamp(2rem, 5vw, 4rem);
  border: 1px solid rgba(255, 255, 255, 0.28);
  background: var(--ink);
  box-shadow: 12px 12px 0 var(--acid);
}

.status-pill {
  display: inline-flex;
  align-items: center;
  gap: 0.55rem;
  font-size: 0.8rem;
  font-weight: 800;
}

.status-pill i {
  width: 0.55rem;
  height: 0.55rem;
  border-radius: 50%;
  background: var(--acid);
  box-shadow: 0 0 0 5px rgba(241, 255, 78, 0.15);
}

.submission-panel h3 {
  margin: 2rem 0 0.6rem;
  font-size: clamp(1.65rem, 3vw, 2.6rem);
  line-height: 1.2;
  letter-spacing: -0.05em;
}

.submission-panel p {
  margin: 0 0 2rem;
  color: rgba(255, 255, 255, 0.62);
}

.submission-panel button,
.submission-link {
  display: flex;
  width: 100%;
  min-height: 3.25rem;
  align-items: center;
  justify-content: space-between;
  padding: 0.7rem 1rem;
  border: 0;
  border-radius: 0;
  color: rgba(18, 25, 55, 0.65);
  background: #dfe1e9;
  cursor: not-allowed;
  font-weight: 900;
}

.submission-link {
  color: var(--ink);
  background: var(--acid);
  cursor: pointer;
}

.guide-section {
  background: var(--white);
}

.guide-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  border-right: 1px solid var(--line);
}

.guide-grid article {
  min-height: 19rem;
  padding: 2rem;
  border-bottom: 1px solid var(--line);
  border-left: 1px solid var(--line);
}

.guide-grid article > span {
  display: block;
  color: var(--electric);
  font-size: 0.8rem;
  font-weight: 900;
}

.guide-grid h3 {
  margin: 5rem 0 0.7rem;
  font-size: 1.5rem;
  letter-spacing: -0.045em;
}

.guide-grid p {
  margin: 0;
  color: var(--muted);
  font-size: 0.95rem;
}

footer {
  display: grid;
  min-height: 11rem;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  gap: 2rem;
  padding: 2rem 5vw;
  background: var(--ink);
  color: var(--white);
}

footer p {
  color: rgba(255, 255, 255, 0.54);
  font-size: 0.82rem;
}

footer > a,
.footer-links {
  justify-self: end;
  font-size: 0.9rem;
  font-weight: 900;
}

.footer-links {
  display: flex;
  gap: 1.2rem;
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
}

[hidden] {
  display: none !important;
}

@media (max-width: 900px) {
  .intro {
    min-height: auto;
    grid-template-columns: 1fr;
  }

  .intro-copy {
    min-height: 70vh;
    border-right: 0;
  }

  .intro-index {
    min-height: 28rem;
  }

  .resource-tools,
  .section-heading {
    align-items: flex-start;
    flex-direction: column;
  }

  .filters {
    justify-content: flex-start;
  }

  .resource-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .submission-section {
    grid-template-columns: 1fr;
  }

  .guide-grid {
    grid-template-columns: 1fr;
  }

  .guide-grid article {
    min-height: auto;
  }

  .guide-grid h3 {
    margin-top: 2.5rem;
  }
}

@media (max-width: 640px) {
  .site-header {
    min-height: 68px;
  }

  .brand > span:last-child {
    font-size: 0.92rem;
  }

  .main-nav a:not(:first-child) {
    display: none;
  }

  h1 {
    font-size: clamp(3.2rem, 16vw, 5rem);
  }

  .intro-copy {
    padding-top: 5rem;
    padding-bottom: 5rem;
  }

  .intro-index a {
    grid-template-columns: 2.5rem 1fr;
  }

  .intro-index a small {
    display: none;
  }

  .resource-grid {
    grid-template-columns: 1fr;
  }

  .resource-card {
    min-height: 21rem;
  }

  .filters {
    display: grid;
    width: 100%;
    grid-template-columns: repeat(2, 1fr);
  }

  footer {
    grid-template-columns: 1fr;
    justify-items: start;
  }

  footer p {
    margin: 0;
  }

  footer > a,
  .footer-links {
    justify-self: start;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    transition-duration: 0.01ms !important;
  }
}