:root {
  --bg: #f5f6fa;
  --surface: #ffffff;
  --text: #1c1e21;
  --text-muted: #6b7280;
  --border: #e2e5ea;
  --primary: #4f46e5;
  --primary-hover: #4338ca;
  --accent: #f0f0ff;
  --ad-bg: #eceef3;
  --shadow: 0 2px 10px rgba(0,0,0,0.05);
}

[data-theme="dark"] {
  --bg: #14161c;
  --surface: #1e2028;
  --text: #e8e9ec;
  --text-muted: #9aa0ab;
  --border: #30323c;
  --primary: #818cf8;
  --primary-hover: #6366f1;
  --accent: #262a3a;
  --ad-bg: #22242e;
  --shadow: 0 2px 10px rgba(0,0,0,0.3);
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Noto Sans KR", Roboto, sans-serif;
  background: var(--bg);
  color: var(--text);
  transition: background 0.2s, color 0.2s;
}

.site-header {
  background: var(--surface);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 10;
}

.header-inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 14px 20px;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.logo { font-size: 1.25rem; margin: 0; }

.header-actions {
  display: flex;
  align-items: center;
  gap: 12px;
}

.lang-switcher {
  display: flex;
  gap: 4px;
  background: var(--accent);
  border: 1px solid var(--border);
  border-radius: 20px;
  padding: 3px;
}

.lang-switcher a {
  text-decoration: none;
  color: var(--text-muted);
  font-size: 0.75rem;
  font-weight: 600;
  padding: 5px 10px;
  border-radius: 16px;
}

.lang-switcher a:hover { color: var(--primary); }

.lang-switcher a.lang-active {
  background: var(--primary);
  color: #fff;
}

.theme-toggle {
  background: var(--accent);
  border: 1px solid var(--border);
  border-radius: 20px;
  padding: 6px 12px;
  cursor: pointer;
  font-size: 1rem;
  color: var(--text);
}

.layout {
  max-width: 1200px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: 160px 1fr 160px;
  gap: 16px;
  padding: 16px 20px;
}

.ad-slot {
  background: var(--ad-bg);
  border: 1px dashed var(--border);
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-muted);
  font-size: 0.8rem;
  text-align: center;
}

.ad-top { min-height: 90px; margin: 0 20px; max-width: 1160px; margin: 0 auto 4px; }
.ad-bottom { min-height: 90px; margin-top: 24px; }
.ad-side { min-height: 400px; position: sticky; top: 80px; }

.content { min-width: 0; }

.intro {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 20px 24px;
  margin-bottom: 20px;
  box-shadow: var(--shadow);
}

.intro h2 { margin-top: 0; font-size: 1.1rem; }
.intro p { color: var(--text-muted); line-height: 1.7; margin-bottom: 0; font-size: 0.92rem; }

.steps {
  margin-top: 16px;
  padding-left: 20px;
  color: var(--text-muted);
  font-size: 0.85rem;
  line-height: 1.8;
}

.tabs {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 20px;
}

.tab-btn {
  background: var(--surface);
  border: 1px solid var(--border);
  color: var(--text-muted);
  padding: 10px 16px;
  border-radius: 8px;
  cursor: pointer;
  font-size: 0.9rem;
  transition: all 0.15s;
}

.tab-btn:hover { border-color: var(--primary); color: var(--primary); }

.tab-btn.active {
  background: var(--primary);
  border-color: var(--primary);
  color: #fff;
}

.panel {
  display: none;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 24px;
  box-shadow: var(--shadow);
}

.panel.active { display: block; }

.panel h2 { margin-top: 0; }

.desc { color: var(--text-muted); font-size: 0.9rem; margin-bottom: 16px; }

.control-row {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
  margin-bottom: 14px;
}

.checkbox-label { display: flex; align-items: center; gap: 4px; font-size: 0.85rem; color: var(--text-muted); }

input[type="text"], input[type="number"], select, textarea {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 8px 10px;
  color: var(--text);
  font-size: 0.9rem;
  font-family: inherit;
}

input[type="file"] { color: var(--text); margin-bottom: 14px; display: block; }

textarea { width: 100%; resize: vertical; }

.btn-primary, .btn-secondary {
  border: none;
  border-radius: 6px;
  padding: 9px 18px;
  font-size: 0.9rem;
  cursor: pointer;
  text-decoration: none;
  display: inline-block;
}

.btn-primary { background: var(--primary); color: #fff; }
.btn-primary:hover { background: var(--primary-hover); }

.btn-secondary { background: var(--accent); color: var(--primary); border: 1px solid var(--border); }
.btn-secondary:hover { background: var(--border); }

.copy-msg { margin-left: 10px; color: #16a34a; font-size: 0.85rem; }

.preview-canvas {
  max-width: 100%;
  margin-top: 12px;
  border-radius: 8px;
  border: 1px solid var(--border);
  display: block;
}

.info-text { color: var(--text-muted); font-size: 0.85rem; }

.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
  gap: 12px;
  margin-top: 16px;
}

.stat-box {
  background: var(--accent);
  border-radius: 8px;
  padding: 14px;
  text-align: center;
}

.stat-box span { display: block; font-size: 1.5rem; font-weight: 700; color: var(--primary); }
.stat-box label { font-size: 0.8rem; color: var(--text-muted); }

#qrResult { margin-top: 16px; display: flex; justify-content: center; }
#qrResult img, #qrResult canvas { border-radius: 8px; background: #fff; padding: 8px; }

.result-box {
  margin-top: 16px;
  background: var(--accent);
  border-radius: 8px;
  padding: 20px;
  font-size: 1.3rem;
  font-weight: 700;
  color: var(--primary);
  text-align: center;
}

.site-footer {
  text-align: center;
  padding: 24px;
  color: var(--text-muted);
  font-size: 0.8rem;
}

.footer-links {
  display: flex;
  justify-content: center;
  gap: 18px;
  margin-bottom: 10px;
}

.footer-links a {
  color: var(--text-muted);
  text-decoration: none;
  font-size: 0.85rem;
}

.footer-links a:hover {
  color: var(--primary);
  text-decoration: underline;
}

/* 정적 페이지(소개/개인정보처리방침/문의) 공통 스타일 */
.static-page {
  max-width: 800px;
  margin: 0 auto;
  padding: 32px 20px 60px;
}

.static-page h1 { font-size: 1.5rem; }
.static-page h2 { font-size: 1.1rem; margin-top: 28px; }
.static-page p, .static-page li { color: var(--text-muted); line-height: 1.8; font-size: 0.95rem; }
.static-page ul { padding-left: 20px; }
.static-page a { color: var(--primary); }

@media (max-width: 900px) {
  .layout { grid-template-columns: 1fr; }
  .ad-side { display: none; }
}