:root {
  --bg: #f3f5f7;
  --line: #d8dde4;
  --text: #07090d;
  --muted: #5b6675;
  --button-bg: #07090d;
  --button-text: #f8fafc;
}

html[data-theme="dark"] {
  --bg: #0d121a;
  --line: #1e2836;
  --text: #f8fafc;
  --muted: #a7b1bf;
  --button-bg: #f8fafc;
  --button-text: #07090d;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: "Pretendard Variable", "Pretendard", "Noto Sans KR",
    "Apple SD Gothic Neo", "Malgun Gothic", sans-serif;
  line-height: 1.45;
}

.site-header {
  height: 72px;
  padding: 0 34px 0 36px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.brand {
  display: inline-flex;
  align-items: center;
  text-decoration: none;
}

.logo {
  width: 136px;
  height: auto;
}

.logo-dark {
  display: none;
}

html[data-theme="dark"] .logo-light {
  display: none;
}

html[data-theme="dark"] .logo-dark {
  display: block;
}

.header-controls {
  display: inline-flex;
  align-items: center;
  gap: 14px;
}

.lang-btn,
.theme-btn {
  border: none;
  background: transparent;
  color: var(--muted);
  cursor: pointer;
  padding: 0;
  font-size: 14px;
  line-height: 1;
}

.lang-btn {
  letter-spacing: 0.02em;
  font-weight: 500;
}

.theme-btn {
  width: 18px;
  height: 18px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
}

.theme-icon {
  width: 17px;
  height: 17px;
  stroke: var(--text);
  fill: none;
  stroke-width: 1.85;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.icon-moon {
  display: block;
}

.icon-sun {
  display: none;
}

html[data-theme="dark"] .icon-moon {
  display: none;
}

html[data-theme="dark"] .icon-sun {
  display: block;
}

.landing {
  width: min(1160px, 94vw);
  margin: 0 auto;
}

.hero {
  text-align: center;
  padding-top: 58px;
}

.hero h1 {
  margin: 0;
  font-size: clamp(36px, 4.4vw, 68px);
  line-height: 1.16;
  letter-spacing: -0.05em;
  font-weight: 800;
}

.hero-sub {
  margin: 24px 0 0;
  color: var(--muted);
  font-size: clamp(16px, 1.25vw, 21px);
  line-height: 1.7;
}

.hero-cta {
  margin-top: 40px;
  display: inline-flex;
  align-items: center;
  gap: 12px;
}

.hero-cta input {
  width: min(320px, 72vw);
  height: 46px;
  border: 1px solid var(--line);
  background: transparent;
  border-radius: 8px;
  padding: 0 16px;
  color: var(--text);
  font-size: 14px;
  outline: none;
}

.hero-cta input::placeholder {
  color: #9aa3b2;
}

.hero-links {
  margin-top: 13px;
  display: flex;
  justify-content: center;
}

.hero-links a {
  color: var(--muted);
  text-decoration: none;
  font-size: 14px;
}

.hero-links a:hover {
  text-decoration: underline;
}

.cta-btn {
  min-width: 154px;
  height: 46px;
  border-radius: 8px;
  border: none;
  background: var(--button-bg);
  color: var(--button-text);
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0 18px;
  font-size: 14px;
  font-weight: 700;
}

.features {
  margin-top: 92px;
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 24px;
}

.feature-card {
  text-align: center;
}

.feature-icon {
  width: 32px;
  height: 32px;
  stroke: var(--text);
  fill: none;
  stroke-width: 1.8;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.feature-card h3 {
  margin: 14px 0 6px;
  font-size: clamp(18px, 1.3vw, 22px);
  font-weight: 700;
  letter-spacing: -0.02em;
}

.feature-card p {
  margin: 0;
  color: var(--muted);
  font-size: clamp(13px, 0.92vw, 15px);
}

.detail {
  margin-top: 96px;
  text-align: center;
}

.detail h2 {
  margin: 0;
  font-size: clamp(32px, 3.2vw, 52px);
  letter-spacing: -0.03em;
  font-weight: 800;
}

.detail-main {
  margin: 22px 0 0;
  font-size: clamp(15px, 1.08vw, 19px);
  line-height: 1.72;
  color: var(--muted);
}

.core-grid {
  margin-top: 46px;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
}

.core-card {
  text-align: center;
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 24px 16px;
}

.core-card h3 {
  margin: 0;
  font-size: clamp(22px, 1.8vw, 30px);
  letter-spacing: -0.02em;
}

.core-card p {
  margin: 14px 0 0;
  font-size: clamp(14px, 1vw, 17px);
  line-height: 1.72;
  color: var(--muted);
}

.api-section {
  margin-top: 40px;
  text-align: center;
}

.api-section h3 {
  margin: 0 0 14px;
  font-size: clamp(22px, 1.8vw, 30px);
}

pre {
  margin: 0 auto;
  width: min(560px, 100%);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 14px;
  background: transparent;
  text-align: left;
  overflow: auto;
}

code {
  font-family: Consolas, "Courier New", monospace;
  font-size: 14px;
  color: var(--text);
  line-height: 1.55;
}

.cta-section {
  margin: 62px 0 84px;
  text-align: center;
}

.cta-section h2 {
  margin: 0 0 18px;
  font-size: clamp(24px, 2.3vw, 38px);
  letter-spacing: -0.02em;
}

.site-footer {
  border-top: 1px solid var(--line);
  background: #eceff3;
  min-height: 116px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 8px;
}

html[data-theme="dark"] .site-footer {
  background: #111824;
}

.footer-logo {
  width: 136px;
  height: auto;
}

.footer-logo-dark {
  display: none;
}

html[data-theme="dark"] .footer-logo-light {
  display: none;
}

html[data-theme="dark"] .footer-logo-dark {
  display: block;
}

.site-footer p {
  margin: 0;
  color: var(--muted);
  font-size: 13px;
}

@media (max-width: 900px) {
  .site-header {
    padding: 0 16px;
    height: 64px;
  }

  .logo {
    width: 124px;
  }

  .hero {
    padding-top: 36px;
  }

  .hero-cta {
    margin-top: 28px;
    width: 100%;
    flex-direction: column;
  }

  .hero-cta input {
    width: min(360px, 100%);
  }

  .cta-btn {
    width: min(360px, 100%);
  }

  .features {
    margin-top: 62px;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 22px 10px;
  }

  .detail {
    margin-top: 62px;
  }

  .core-grid {
    margin-top: 24px;
    grid-template-columns: 1fr;
  }

  .api-section,
  .cta-section {
    margin-top: 26px;
  }

  .cta-section {
    margin-bottom: 56px;
  }
}

@media (max-width: 560px) {
  .features {
    grid-template-columns: 1fr;
  }

  .hero-sub br,
  .detail-main br,
  .core-card p br {
    display: none;
  }
}