/* ===== 기본 ===== */
* { box-sizing: border-box; }
html, body { height: 100%; }
body {
  margin: 0;
  font-family: system-ui, -apple-system, Segoe UI, Roboto, "Noto Sans KR", Arial, sans-serif;
  line-height: 1.5;
  color: #0f172a;
  background: #ffffff;
}

a { color: inherit; text-decoration: none; }
.container { width: min(1100px, 92%); margin: 0 auto; }

/* ===== Header ===== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid #e2e8f0;
}
.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 14px 0;
  gap: 12px;
}

.brand { display: flex; align-items: center; gap: 10px; font-weight: 800; }
.brand-mark {
  width: 34px; height: 34px;
  display: grid; place-items: center;
  border-radius: 10px;
  border: 1px solid #e2e8f0;
  background: #f8fafc;
}
.brand-name { letter-spacing: -0.02em; }

.nav { display: flex; gap: 18px; align-items: center; }
.nav a { color: #334155; font-weight: 600; }
.nav a:hover { color: #0f172a; }

.nav-cta {
  padding: 10px 12px;
  border-radius: 12px;
  border: 1px solid #e2e8f0;
  background: #f8fafc;
}

.nav-toggle {
  display: none;
  border: 1px solid #e2e8f0;
  background: #fff;
  border-radius: 12px;
  padding: 10px 12px;
  font-size: 16px;
  cursor: pointer;
}

/* 모바일 메뉴 */
@media (max-width: 820px) {
  .nav { display: none; }
  .nav-toggle { display: inline-flex; }
  body.nav-open .nav {
    display: flex;
    position: absolute;
    left: 4%;
    right: 4%;
    top: 62px;
    flex-direction: column;
    align-items: stretch;
    gap: 10px;
    padding: 12px;
    border: 1px solid #e2e8f0;
    border-radius: 16px;
    background: rgba(255, 255, 255, 0.98);
  }
  body.nav-open .nav a { padding: 10px 12px; border-radius: 12px; }
  body.nav-open .nav a:hover { background: #f1f5f9; }
}

/* ===== Hero ===== */
.hero {
  padding: 64px 0 40px;
  background: radial-gradient(900px 400px at 15% 10%, #e0f2fe 0%, rgba(224,242,254,0) 60%),
              radial-gradient(800px 400px at 85% 20%, #fce7f3 0%, rgba(252,231,243,0) 55%);
}

.hero-inner {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 28px;
  align-items: start;
}

@media (max-width: 920px) {
  .hero-inner { grid-template-columns: 1fr; }
}

.pill {
  display: inline-flex;
  padding: 8px 12px;
  border-radius: 999px;
  background: #f1f5f9;
  border: 1px solid #e2e8f0;
  color: #334155;
  font-weight: 700;
  margin: 0 0 12px;
}

.hero h1 {
  margin: 0 0 10px;
  font-size: clamp(32px, 4vw, 46px);
  line-height: 1.1;
  letter-spacing: -0.03em;
}

.sub { margin: 0 0 18px; color: #475569; font-size: 16.5px; }

.hero-actions { display: flex; gap: 12px; flex-wrap: wrap; margin-bottom: 18px; }

/* 버튼 */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 14px;
  border-radius: 14px;
  border: 1px solid #e2e8f0;
  background: #ffffff;
  font-weight: 800;
  cursor: pointer;
}
.btn:hover { filter: brightness(0.98); }

.btn.primary {
  background: #0f172a;
  color: #ffffff;
  border-color: #0f172a;
}

.btn.ghost { background: #ffffff; color: #0f172a; }

.btn.block { width: 100%; }

/* 통계 */
.hero-stats {
  display: flex;
  gap: 18px;
  flex-wrap: wrap;
  padding-top: 8px;
}
.stat { min-width: 120px; }
.stat-num { display: block; font-weight: 900; font-size: 20px; }
.stat-label { display: block; color: #64748b; font-size: 13px; }

/* 카드 */
.card {
  border: 1px solid #e2e8f0;
  border-radius: 18px;
  background: rgba(255, 255, 255, 0.9);
  box-shadow: 0 10px 30px rgba(15, 23, 42, 0.08);
  padding: 18px;
}
.card h3 { margin: 0 0 6px; }
.card hr { border: none; border-top: 1px solid #e2e8f0; margin: 14px 0; }

.hero-card .card { position: sticky; top: 90px; }

.muted { color: #64748b; }
.small { font-size: 13px; }

.card-row { display: flex; gap: 8px; flex-wrap: wrap; margin-top: 10px; }
.tag {
  font-size: 12px;
  padding: 6px 10px;
  border-radius: 999px;
  border: 1px solid #e2e8f0;
  background: #f8fafc;
  color: #334155;
  font-weight: 700;
}

/* ===== Section ===== */
.section { padding: 64px 0; }
.section.alt { background: #f8fafc; }

.section-head { margin-bottom: 18px; }
.section-head h2 {
  margin: 0 0 6px;
  font-size: 28px;
  letter-spacing: -0.02em;
}

/* 그리드 */
.grid-2, .grid-3, .grid-4 { display: grid; gap: 16px; }
.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }

@media (max-width: 920px) {
  .grid-2 { grid-template-columns: 1fr; }
  .grid-3 { grid-template-columns: 1fr; }
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 520px) {
  .grid-4 { grid-template-columns: 1fr; }
}

.feature {
  border: 1px solid #e2e8f0;
  border-radius: 18px;
  padding: 18px;
  background: #ffffff;
}
.feature h3 { margin: 0 0 8px; }

/* 활동 카드 */
.activity ul { margin: 10px 0 0; padding-left: 18px; color: #334155; }
.activity li { margin: 6px 0; }

.spaced { margin-top: 18px; }
.mini {
  border: 1px solid #e2e8f0;
  border-radius: 18px;
  padding: 16px;
  background: #ffffff;
}
.mini h4 { margin: 0 0 6px; }

/* 멤버 */
.member {
  border: 1px solid #e2e8f0;
  border-radius: 18px;
  padding: 14px;
  display: flex;
  align-items: center;
  gap: 12px;
  background: #ffffff;
}
.avatar {
  width: 44px; height: 44px;
  display: grid; place-items: center;
  border-radius: 14px;
  border: 1px solid #e2e8f0;
  background: #f8fafc;
  font-size: 20px;
}
.member-info { display: grid; gap: 2px; }

/* Join */
.join { background: linear-gradient(180deg, #ffffff 0%, #f8fafc 100%); }
.join-box {
  border: 1px solid #e2e8f0;
  border-radius: 22px;
  padding: 22px;
  background: #ffffff;
  display: grid;
  grid-template-columns: 1fr 1fr 0.8fr;
  gap: 18px;
  align-items: start;
}

@media (max-width: 980px) {
  .join-box { grid-template-columns: 1fr; }
}

.join-form label { display: grid; gap: 6px; margin-bottom: 10px; }
.label { font-weight: 800; font-size: 13px; color: #334155; }

input, textarea {
  width: 100%;
  padding: 12px 12px;
  border: 1px solid #e2e8f0;
  border-radius: 14px;
  font-size: 14px;
  outline: none;
}
input:focus, textarea:focus { border-color: #94a3b8; }

.join-links { display: grid; gap: 10px; }
.link {
  border: 1px solid #e2e8f0;
  border-radius: 14px;
  padding: 12px;
  background: #f8fafc;
  font-weight: 800;
}
.link:hover { filter: brightness(0.98); }

/* Footer */
.footer {
  border-top: 1px solid #e2e8f0;
  padding: 22px 0;
  background: #ffffff;
}
.footer-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
  flex-wrap: wrap;
}
.footer-links { display: flex; gap: 14px; }
.footer-links a { color: #64748b; font-weight: 700; }
.footer-links a:hover { color: #0f172a; }