*{box-sizing:border-box} body{margin:0;font-family:-apple-system,"Noto Sans KR",sans-serif;background:#f3f4f6;color:#1f2937}
a{color:#2563eb;text-decoration:none} a:hover{text-decoration:underline}
.layout{display:flex;min-height:100vh}
.sidebar{width:240px;background:#111827;color:#e5e7eb;padding:20px 14px;flex-shrink:0}
.sidebar h1{font-size:19px;margin:0 0 4px} .sidebar h1 a{color:#fff}
.sidebar .sub{font-size:12px;color:#9ca3af;margin-bottom:20px}
.nav-group{margin:12px 0 0}
.main-menu{width:100%;text-align:left;background:none;border:0;color:#fff;font-size:15px;font-weight:700;padding:10px;border-radius:8px;cursor:pointer;display:flex;justify-content:space-between;align-items:center;font-family:inherit}
.main-menu:hover{background:#1f2937}
.main-menu .arrow{transition:transform .15s;font-size:12px}
.main-menu.open .arrow{transform:rotate(180deg)}
.submenu{display:none}
.submenu.open{display:block}
.sidebar a.item{display:block;color:#e5e7eb;padding:9px 10px;border-radius:8px;font-size:14px}
.sidebar a.item:hover{background:#1f2937;text-decoration:none}
.sidebar a.item.active{background:#2563eb;color:#fff}
.sidebar a.subitem{padding-left:26px;font-size:13px;color:#d1d5db}
.main{flex:1;padding:24px;max-width:1000px}
.topbar{display:flex;justify-content:space-between;align-items:center;margin-bottom:18px}
.topbar h2{margin:0;font-size:22px}
.card{background:#fff;border:1px solid #e5e7eb;border-radius:12px;padding:18px;margin-bottom:16px}
.grid{display:grid;grid-template-columns:repeat(4,1fr);gap:12px}
.stat .num{font-size:26px;font-weight:700;margin-top:4px}
.stat .lbl{font-size:13px;color:#6b7280}
table{width:100%;border-collapse:collapse;font-size:14px}
th,td{padding:9px 8px;border-bottom:1px solid #e5e7eb;text-align:left}
th{color:#6b7280;font-size:12px}
.btn{display:inline-block;background:#2563eb;color:#fff;padding:8px 14px;border-radius:8px;border:0;cursor:pointer;font-size:14px}
.btn:hover{text-decoration:none;background:#1d4ed8}
.btn.ghost{background:#fff;color:#374151;border:1px solid #d1d5db}
.btn.danger{background:#dc2626}
input,select,textarea{width:100%;padding:9px 10px;border:1px solid #d1d5db;border-radius:8px;font-size:14px;margin:4px 0 12px;background:#fff}
label{font-size:13px;color:#374151;font-weight:600}
.flash{background:#fef3c7;border:1px solid #f59e0b;padding:10px 12px;border-radius:8px;margin-bottom:14px;font-size:14px}
.note{font-size:13px;color:#6b7280}
.login{max-width:380px;margin:80px auto;background:#fff;padding:28px;border-radius:12px;border:1px solid #e5e7eb}
.login h1{margin:0 0 6px;font-size:22px}
@media(max-width:760px){.layout{flex-direction:column}.sidebar{width:100%}.grid{grid-template-columns:repeat(2,1fr)}.main{padding:14px}}