:root {
  --bg: #ffffff;
  --bg-soft: #f7f8fa;
  --bg-softer: #fafbfc;
  --text: #191f28;
  --text-sub: #4e5968;
  --text-mute: #8b95a1;
  --line: #e5e8eb;
  --line-soft: #f1f3f5;

  --brand: #3182f6;
  --brand-hover: #1b64da;
  --brand-soft: #e8f3ff;

  --accent: #ff6b4a;
  --accent-soft: #fff4ef;

  --free: #00c471;
  --free-soft: #e6f9f1;

  --radius: 16px;
  --radius-lg: 24px;
  --radius-xl: 32px;

  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.04);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.08);

  --max: 1120px;
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: "Pretendard Variable", Pretendard, -apple-system, BlinkMacSystemFont, "Apple SD Gothic Neo", "Noto Sans KR", sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  font-feature-settings: "ss03", "ss04";
}

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

/* ---------- NAV ---------- */
.nav {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: saturate(180%) blur(12px);
  -webkit-backdrop-filter: saturate(180%) blur(12px);
  border-bottom: 1px solid var(--line-soft);
}
.nav-inner {
  max-width: var(--max);
  margin: 0 auto;
  padding: 16px 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.brand {
  font-weight: 700;
  font-size: 17px;
  letter-spacing: -0.02em;
}
.nav-links {
  display: flex;
  align-items: center;
  gap: 28px;
  font-size: 15px;
  color: var(--text-sub);
  font-weight: 500;
}
.nav-links a:hover {
  color: var(--text);
}
.nav-gh {
  background: var(--text);
  color: #fff !important;
  padding: 8px 16px;
  border-radius: 999px;
  font-size: 14px;
}
.nav-gh:hover {
  background: #333;
}
@media (max-width: 720px) {
  .nav-links a:not(.nav-gh) {
    display: none;
  }
}

/* ---------- HERO ---------- */
.hero {
  padding: 80px 24px 100px;
  background: linear-gradient(180deg, #fff 0%, var(--bg-soft) 100%);
  position: relative;
  overflow: hidden;
}
.hero::before {
  content: "";
  position: absolute;
  top: -200px;
  right: -200px;
  width: 600px;
  height: 600px;
  background: radial-gradient(circle, var(--brand-soft) 0%, transparent 70%);
  border-radius: 50%;
  pointer-events: none;
}
.hero::after {
  content: "";
  position: absolute;
  bottom: -300px;
  left: -200px;
  width: 500px;
  height: 500px;
  background: radial-gradient(circle, var(--accent-soft) 0%, transparent 70%);
  border-radius: 50%;
  pointer-events: none;
}
.hero-inner {
  max-width: var(--max);
  margin: 0 auto;
  text-align: center;
  position: relative;
}
.hero-badge {
  display: inline-block;
  background: var(--accent-soft);
  color: var(--accent);
  font-weight: 700;
  font-size: 14px;
  padding: 8px 16px;
  border-radius: 999px;
  margin-bottom: 32px;
  letter-spacing: -0.01em;
}
.hero-title {
  font-size: clamp(36px, 6vw, 64px);
  font-weight: 800;
  letter-spacing: -0.04em;
  line-height: 1.2;
  margin-bottom: 24px;
}
.hero-title .accent {
  color: var(--brand);
  position: relative;
  display: inline-block;
}
.hero-title .accent::after {
  content: "";
  position: absolute;
  bottom: 4px;
  left: 0;
  right: 0;
  height: 10px;
  background: var(--brand-soft);
  z-index: -1;
  border-radius: 4px;
}
.hero-sub {
  font-size: clamp(16px, 2vw, 19px);
  color: var(--text-sub);
  line-height: 1.7;
  margin-bottom: 40px;
  font-weight: 500;
}
.hero-cta {
  display: flex;
  gap: 12px;
  justify-content: center;
  align-items: center;
  flex-wrap: wrap;
  margin-bottom: 32px;
}
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  padding: 18px 32px;
  border-radius: var(--radius);
  font-weight: 700;
  font-size: 17px;
  transition: transform 0.15s ease, box-shadow 0.2s ease, background 0.2s;
  letter-spacing: -0.02em;
  cursor: pointer;
  border: none;
}
.btn-primary {
  background: var(--brand);
  color: #fff;
  flex-direction: column;
  padding: 14px 36px;
  box-shadow: var(--shadow-md);
}
.btn-primary:hover {
  background: var(--brand-hover);
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}
.btn-primary .btn-label {
  font-size: 17px;
}
.btn-primary .btn-sub {
  font-size: 12px;
  font-weight: 500;
  opacity: 0.85;
}
.btn-ghost {
  background: transparent;
  color: var(--text-sub);
  padding: 18px 20px;
}
.btn-ghost:hover {
  color: var(--text);
}
.btn-lg {
  padding: 20px 48px;
  font-size: 19px;
}
.hero-meta {
  font-size: 14px;
  color: var(--text-mute);
  display: inline-flex;
  align-items: center;
  gap: 8px;
}
.hero-meta .dot {
  width: 6px;
  height: 6px;
  background: var(--free);
  border-radius: 50%;
  display: inline-block;
}

/* ---------- SECTIONS ---------- */
.section-inner {
  max-width: var(--max);
  margin: 0 auto;
  padding: 100px 24px;
}
.section-title {
  font-size: clamp(28px, 4vw, 40px);
  font-weight: 800;
  letter-spacing: -0.03em;
  line-height: 1.3;
  text-align: center;
  margin-bottom: 16px;
}
.section-sub {
  font-size: 17px;
  color: var(--text-sub);
  text-align: center;
  margin-bottom: 64px;
  font-weight: 500;
}

/* ---------- USECASE CARDS ---------- */
.usecase {
  background: var(--bg);
}
.cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 20px;
}
.card {
  background: var(--bg-soft);
  border-radius: var(--radius-lg);
  padding: 32px;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}
.card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
  background: #fff;
}
.card-icon {
  font-size: 40px;
  margin-bottom: 16px;
  line-height: 1;
}
.card h3 {
  font-size: 20px;
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: 8px;
}
.card p {
  font-size: 15px;
  color: var(--text-sub);
  line-height: 1.6;
}

/* ---------- META (AI made) ---------- */
.meta {
  background: linear-gradient(135deg, #191f28 0%, #2d3540 100%);
  color: #fff;
}
.meta-inner {
  text-align: center;
}
.meta-tag {
  display: inline-block;
  background: rgba(255, 255, 255, 0.1);
  color: #fff;
  font-weight: 700;
  font-size: 12px;
  letter-spacing: 0.15em;
  padding: 8px 16px;
  border-radius: 999px;
  margin-bottom: 24px;
  border: 1px solid rgba(255, 255, 255, 0.15);
}
.meta .section-title {
  color: #fff;
}
.meta-body {
  font-size: 17px;
  color: rgba(255, 255, 255, 0.8);
  line-height: 1.8;
  margin: 24px auto 48px;
  max-width: 640px;
}
.meta-body strong {
  color: #fff;
  background: linear-gradient(120deg, transparent 0%, transparent 45%, var(--accent) 45%, var(--accent) 55%, transparent 55%);
  padding: 0 4px;
}
.meta-proof {
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: var(--radius-lg);
  padding: 32px;
  max-width: 520px;
  margin: 0 auto;
  text-align: left;
}
.proof-line {
  font-size: 15px;
  color: rgba(255, 255, 255, 0.85);
  padding: 10px 0;
  border-bottom: 1px dashed rgba(255, 255, 255, 0.1);
  font-weight: 500;
}
.proof-line:last-of-type {
  border-bottom: none;
}
.proof-arrow {
  text-align: center;
  font-size: 24px;
  color: var(--accent);
  margin: 12px 0;
}
.proof-result {
  text-align: center;
  background: var(--accent);
  color: #fff;
  padding: 14px;
  border-radius: var(--radius);
  font-weight: 700;
  font-size: 16px;
}

/* ---------- START (tracks) ---------- */
.start {
  background: var(--bg-soft);
}
.tracks {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 20px;
  margin-bottom: 32px;
}
.track {
  display: block;
  background: #fff;
  border-radius: var(--radius-lg);
  padding: 36px;
  border: 2px solid transparent;
  transition: transform 0.2s ease, box-shadow 0.2s ease, border-color 0.2s;
  position: relative;
}
.track:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}
.track-free:hover {
  border-color: var(--free);
}
.track-paid:hover {
  border-color: var(--brand);
}
.track-badge {
  display: inline-block;
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.05em;
  padding: 6px 12px;
  border-radius: 999px;
  margin-bottom: 20px;
}
.track-free .track-badge {
  background: var(--free-soft);
  color: var(--free);
}
.track-paid .track-badge {
  background: var(--brand-soft);
  color: var(--brand);
}
.track h3 {
  font-size: 26px;
  font-weight: 800;
  letter-spacing: -0.03em;
  margin-bottom: 8px;
}
.track-sub {
  font-size: 16px;
  color: var(--text-mute);
  font-weight: 500;
}
.track-desc {
  font-size: 16px;
  color: var(--text-sub);
  margin-bottom: 24px;
  line-height: 1.6;
}
.track-feats {
  list-style: none;
  margin-bottom: 28px;
}
.track-feats li {
  padding: 8px 0;
  font-size: 15px;
  color: var(--text-sub);
  font-weight: 500;
}
.track-cta {
  font-size: 16px;
  font-weight: 700;
  color: var(--text);
  border-top: 1px solid var(--line-soft);
  padding-top: 20px;
}
.track-free .track-cta {
  color: var(--free);
}
.track-paid .track-cta {
  color: var(--brand);
}
.start-note {
  text-align: center;
  color: var(--text-sub);
  font-size: 15px;
  padding: 20px;
  background: #fff;
  border-radius: var(--radius);
  border: 1px dashed var(--line);
}
.start-note a {
  color: var(--brand);
  font-weight: 600;
  text-decoration: underline;
  text-underline-offset: 3px;
}

/* ---------- HONESTY ---------- */
.honesty {
  background: var(--bg);
}
.honest-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 20px;
}
.honest-item {
  background: var(--bg-soft);
  padding: 28px;
  border-radius: var(--radius-lg);
}
.honest-label {
  font-size: 14px;
  color: var(--text-mute);
  font-weight: 600;
  margin-bottom: 8px;
}
.honest-value {
  font-size: 24px;
  font-weight: 800;
  letter-spacing: -0.02em;
  margin-bottom: 12px;
}
.honest-note {
  font-size: 14px;
  color: var(--text-sub);
  line-height: 1.6;
}

/* ---------- CLOSING ---------- */
.closing {
  background: linear-gradient(135deg, var(--brand-soft) 0%, var(--accent-soft) 100%);
}
.closing-inner {
  text-align: center;
  padding: 120px 24px;
}
.closing-title {
  font-size: clamp(32px, 5vw, 48px);
  font-weight: 800;
  letter-spacing: -0.03em;
  margin-bottom: 16px;
}
.closing-sub {
  font-size: 17px;
  color: var(--text-sub);
  margin-bottom: 40px;
}

/* ---------- FOOTER ---------- */
.foot {
  background: #fff;
  border-top: 1px solid var(--line-soft);
}
.foot-inner {
  max-width: var(--max);
  margin: 0 auto;
  padding: 40px 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 20px;
}
.foot-brand {
  font-weight: 700;
  font-size: 16px;
  margin-bottom: 4px;
}
.foot-by {
  font-size: 13px;
  color: var(--text-mute);
}
.foot-by a {
  color: var(--text-sub);
  font-weight: 600;
}
.foot-right {
  display: flex;
  gap: 24px;
}
.foot-right a {
  font-size: 14px;
  color: var(--text-sub);
  font-weight: 500;
}
.foot-right a:hover {
  color: var(--text);
}

/* ---------- GUIDE PAGES ---------- */
.guide-hero {
  padding: 64px 24px 48px;
  background: linear-gradient(180deg, var(--brand-soft) 0%, #fff 100%);
  border-bottom: 1px solid var(--line-soft);
}
.guide-free-hero {
  background: linear-gradient(180deg, var(--free-soft) 0%, #fff 100%);
}
.guide-hero-inner {
  max-width: 760px;
  margin: 0 auto;
}
.guide-crumb {
  font-size: 14px;
  color: var(--text-mute);
  margin-bottom: 16px;
  font-weight: 500;
}
.guide-crumb a {
  color: var(--text-sub);
}
.guide-crumb a:hover {
  color: var(--text);
  text-decoration: underline;
}
.guide-title {
  font-size: clamp(28px, 4vw, 40px);
  font-weight: 800;
  letter-spacing: -0.03em;
  line-height: 1.3;
  margin-bottom: 16px;
}
.guide-lead {
  font-size: 17px;
  color: var(--text-sub);
  line-height: 1.7;
  margin-bottom: 24px;
}
.guide-meta {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  margin-top: 24px;
}
.guide-pill {
  background: #fff;
  border: 1px solid var(--line);
  padding: 10px 16px;
  border-radius: 999px;
  font-size: 14px;
  color: var(--text-sub);
  font-weight: 500;
}
.guide-pill strong {
  color: var(--text);
  font-weight: 700;
}

.guide-body {
  max-width: 760px;
  margin: 0 auto;
  padding: 64px 24px 96px;
}
.guide-body h2 {
  font-size: 28px;
  font-weight: 800;
  letter-spacing: -0.02em;
  margin: 64px 0 16px;
  padding-bottom: 12px;
  border-bottom: 2px solid var(--line-soft);
}
.guide-body h2:first-child {
  margin-top: 0;
}
.guide-body h3 {
  font-size: 20px;
  font-weight: 700;
  letter-spacing: -0.02em;
  margin: 40px 0 12px;
}
.guide-body p {
  font-size: 16px;
  line-height: 1.8;
  color: var(--text);
  margin-bottom: 16px;
}
.guide-body ul, .guide-body ol {
  font-size: 16px;
  line-height: 1.9;
  color: var(--text);
  padding-left: 24px;
  margin-bottom: 20px;
}
.guide-body li {
  margin-bottom: 6px;
}
.guide-body a {
  color: var(--brand);
  font-weight: 500;
  text-decoration: underline;
  text-underline-offset: 3px;
  text-decoration-thickness: 1px;
}
.guide-body a:hover {
  text-decoration-thickness: 2px;
}
.guide-body code {
  background: var(--bg-soft);
  color: #d63384;
  padding: 2px 8px;
  border-radius: 6px;
  font-family: "JetBrains Mono", "SF Mono", Consolas, monospace;
  font-size: 0.92em;
  font-weight: 500;
}
.guide-body pre {
  background: #191f28;
  color: #f8f9fa;
  padding: 20px 24px;
  border-radius: var(--radius);
  overflow-x: auto;
  margin: 16px 0 24px;
  font-size: 14px;
  line-height: 1.7;
}
.guide-body pre code {
  background: transparent;
  color: inherit;
  padding: 0;
  font-size: 14px;
  font-weight: 400;
}
.guide-body img {
  max-width: 100%;
  border-radius: var(--radius);
  margin: 16px 0;
  border: 1px solid var(--line-soft);
}
.guide-body blockquote {
  background: var(--bg-soft);
  border-left: 4px solid var(--brand);
  padding: 16px 20px;
  margin: 20px 0;
  border-radius: 8px;
  color: var(--text-sub);
}
.guide-body blockquote p {
  margin-bottom: 8px;
}
.guide-body blockquote p:last-child {
  margin-bottom: 0;
}
.guide-body table {
  border-collapse: collapse;
  width: 100%;
  margin: 20px 0;
  font-size: 15px;
}
.guide-body th, .guide-body td {
  padding: 12px 16px;
  text-align: left;
  border-bottom: 1px solid var(--line-soft);
}
.guide-body th {
  background: var(--bg-soft);
  font-weight: 700;
  font-size: 14px;
  color: var(--text-sub);
}
.guide-body hr {
  border: none;
  border-top: 1px solid var(--line-soft);
  margin: 48px 0;
}

.guide-step {
  background: var(--bg-soft);
  border-radius: var(--radius-lg);
  padding: 28px 32px;
  margin: 24px 0;
  border-left: 4px solid var(--brand);
}
.guide-step-num {
  display: inline-block;
  background: var(--brand);
  color: #fff;
  font-weight: 700;
  font-size: 13px;
  padding: 4px 12px;
  border-radius: 999px;
  margin-bottom: 12px;
  letter-spacing: 0.02em;
}
.guide-free-hero ~ .guide-body .guide-step {
  border-left-color: var(--free);
}
.guide-free-hero ~ .guide-body .guide-step-num {
  background: var(--free);
}

.guide-success {
  background: var(--free-soft);
  border: 1px solid #b8e6cf;
  border-radius: var(--radius);
  padding: 16px 20px;
  margin: 16px 0;
  color: #0a6e3e;
  font-weight: 500;
}
.guide-success strong {
  color: var(--free);
}

.guide-warning {
  background: var(--accent-soft);
  border: 1px solid #ffccba;
  border-radius: var(--radius);
  padding: 16px 20px;
  margin: 16px 0;
  color: #c54922;
  font-weight: 500;
}

.guide-tip {
  background: var(--brand-soft);
  border: 1px solid #c2daff;
  border-radius: var(--radius);
  padding: 16px 20px;
  margin: 16px 0;
  color: #1b4ea0;
  font-weight: 500;
}

.guide-nav-bottom {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  margin-top: 64px;
  padding-top: 32px;
  border-top: 2px solid var(--line-soft);
  flex-wrap: wrap;
}
.guide-nav-btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: var(--bg-soft);
  color: var(--text);
  padding: 14px 20px;
  border-radius: var(--radius);
  font-weight: 600;
  font-size: 15px;
  transition: background 0.2s;
}
.guide-nav-btn:hover {
  background: var(--line-soft);
}

/* ---------- RESPONSIVE ---------- */
@media (max-width: 720px) {
  .section-inner {
    padding: 64px 20px;
  }
  .hero {
    padding: 56px 20px 72px;
  }
  .hero-cta {
    flex-direction: column;
    width: 100%;
  }
  .btn {
    width: 100%;
    max-width: 320px;
  }
  .nav-inner {
    padding: 14px 20px;
  }
  .card, .track, .honest-item {
    padding: 24px;
  }
  .meta-proof {
    padding: 24px;
  }
}