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

:root {
  --color-bg: #fafafa;
  --color-surface: #ffffff;
  --color-text: #111111;
  --color-text-secondary: #555555;
  --color-border: #e0e0e0;
  --color-accent: #111111;
  --color-tag-bg: #f0f0f0;
  --radius: 12px;
}

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  background: var(--color-bg);
  color: var(--color-text);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

/* Nav */
header {
  position: sticky;
  top: 0;
  background: rgba(250, 250, 250, 0.85);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--color-border);
  z-index: 10;
}

nav {
  max-width: 960px;
  margin: 0 auto;
  padding: 16px 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.logo {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--color-text);
  text-decoration: none;
  letter-spacing: -0.02em;
}

.nav-links {
  display: flex;
  gap: 24px;
}

.nav-links a {
  color: var(--color-text-secondary);
  text-decoration: none;
  font-size: 0.9rem;
  font-weight: 500;
  transition: color 0.15s;
}

.nav-links a:hover {
  color: var(--color-text);
}

/* Hero */
.hero {
  max-width: 960px;
  margin: 0 auto;
  padding: 100px 24px 80px;
  text-align: center;
}

.hero h1 {
  font-size: 2.75rem;
  font-weight: 700;
  line-height: 1.2;
  letter-spacing: -0.03em;
}

.hero p {
  margin-top: 20px;
  font-size: 1.15rem;
  color: var(--color-text-secondary);
  max-width: 520px;
  margin-left: auto;
  margin-right: auto;
}

/* Services */
.services {
  max-width: 960px;
  margin: 0 auto;
  padding: 0 24px 120px;
}

.services h2 {
  font-size: 1.1rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--color-text-secondary);
  margin-bottom: 32px;
}

.service-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 24px;
}

.service-card {
  display: block;
  text-decoration: none;
  color: inherit;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 32px;
  transition: border-color 0.15s, box-shadow 0.15s;
}

.service-card:hover {
  border-color: #999;
  box-shadow: 0 4px 24px rgba(0, 0, 0, 0.06);
}

.service-icon {
  font-size: 2rem;
  margin-bottom: 16px;
}

.service-card h3 {
  font-size: 1.25rem;
  font-weight: 600;
  margin-bottom: 8px;
}

.service-card p {
  color: var(--color-text-secondary);
  font-size: 0.95rem;
  line-height: 1.6;
  margin-bottom: 20px;
}

.service-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.service-tags span {
  font-size: 0.78rem;
  font-weight: 500;
  background: var(--color-tag-bg);
  color: var(--color-text-secondary);
  padding: 4px 10px;
  border-radius: 6px;
}

/* Project Page */
.project-page {
  max-width: 720px;
  margin: 0 auto;
  padding: 60px 24px 100px;
}

.project-header {
  margin-bottom: 48px;
}

.project-header .project-icon {
  font-size: 3rem;
  margin-bottom: 16px;
}

.project-header h1 {
  font-size: 2.5rem;
  font-weight: 700;
  letter-spacing: -0.03em;
  line-height: 1.2;
  margin-bottom: 12px;
}

.project-header .korean {
  font-weight: 400;
  color: var(--color-text-secondary);
}

.project-subtitle {
  font-size: 1.15rem;
  color: var(--color-text-secondary);
  margin-bottom: 20px;
}

.project-section {
  margin-bottom: 40px;
}

.project-section h2 {
  font-size: 1.25rem;
  font-weight: 600;
  margin-bottom: 16px;
  letter-spacing: -0.01em;
}

.project-section p {
  color: var(--color-text-secondary);
  font-size: 0.95rem;
  line-height: 1.7;
}

.feature-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.feature-list li {
  color: var(--color-text-secondary);
  font-size: 0.95rem;
  padding-left: 20px;
  position: relative;
}

.feature-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 10px;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--color-border);
}

.preset-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 16px;
}

.preset-group {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 20px;
}

.preset-group h3 {
  font-size: 0.9rem;
  font-weight: 600;
  margin-bottom: 8px;
}

.preset-group p {
  font-size: 0.85rem;
  color: var(--color-text-secondary);
  line-height: 1.5;
}

.how-to-play {
  list-style: none;
  counter-reset: step;
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.how-to-play li {
  counter-increment: step;
  padding-left: 40px;
  position: relative;
}

.how-to-play li::before {
  content: counter(step);
  position: absolute;
  left: 0;
  top: 0;
  width: 28px;
  height: 28px;
  border-radius: 50%;
  background: var(--color-text);
  color: var(--color-bg);
  font-size: 0.8rem;
  font-weight: 600;
  display: flex;
  align-items: center;
  justify-content: center;
}

.how-to-play li strong {
  display: block;
  font-size: 1rem;
  margin-bottom: 4px;
}

.how-to-play li p {
  color: var(--color-text-secondary);
  font-size: 0.9rem;
}

/* Footer */
footer {
  border-top: 1px solid var(--color-border);
  text-align: center;
  padding: 32px 24px;
}

footer p {
  font-size: 0.85rem;
  color: var(--color-text-secondary);
}

/* Responsive */
@media (max-width: 640px) {
  .hero h1 {
    font-size: 2rem;
  }

  .hero {
    padding: 60px 24px 50px;
  }

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