:root{
  --bg:#F3F6F6;
  --panel:#FFFFFF;
  --ink:#182B2E;
  --muted:#5C7278;
  --line:#DCE6E6;
  --accent:#1F6E7A;
  --accent-dark:#175560;
  --danger:#B5442E;
  --danger-bg:#FBEAE5;
  --warn:#B98A2A;
  --warn-bg:#FBF3E3;
  --ok-bg:#E6F0EE;
  --sidebar:#0F2226;
}
*{box-sizing:border-box;}
body{margin:0; font-family:'IBM Plex Sans', sans-serif; background:var(--bg); color:var(--ink); font-size:15px;}
a{color:inherit; text-decoration:none;}
h1,h2,h3{margin:0 0 6px; font-weight:600;}
p{margin:0; color:var(--muted);}

.app{display:grid; grid-template-columns:230px 1fr; min-height:100vh;}
.sidebar{background:var(--sidebar); color:#B9CBCD; padding:26px 16px; display:flex; flex-direction:column; gap:28px;}
.brand{font-size:1.15rem; font-weight:700; color:#fff;}
.brand span{color:var(--accent); font-weight:400;}
.sidebar nav{display:flex; flex-direction:column; gap:2px; flex:1;}
.sidebar nav > a{padding:10px 12px; border-radius:4px; font-size:0.92rem; color:#B9CBCD;}
.sidebar nav > a:hover{color:#fff;}
.sidebar nav > a.active{background:rgba(255,255,255,0.08); color:#fff; font-weight:500;}

.nav-group{border:none;}
.nav-group summary{
  padding:10px 12px; border-radius:4px; font-size:0.92rem; color:#B9CBCD; cursor:pointer;
  list-style:none; display:flex; align-items:center; justify-content:space-between;
}
.nav-group summary::-webkit-details-marker{display:none;}
.nav-group summary::after{content:'›'; transform:rotate(90deg); transition:transform .15s ease; font-size:1rem;}
.nav-group[open] summary::after{transform:rotate(270deg);}
.nav-group summary:hover{color:#fff;}
.nav-sub{display:flex; flex-direction:column; gap:1px; padding:2px 0 4px 14px;}
.nav-sub a{padding:9px 12px; border-radius:4px; font-size:0.88rem; color:#9FB4B6; border-left:1px solid rgba(255,255,255,0.12);}
.nav-sub a:hover{color:#fff;}
.nav-sub a.active{background:rgba(255,255,255,0.08); color:#fff; font-weight:500; border-left-color:var(--accent);}
.sidebar-bottom{border-top:1px solid rgba(255,255,255,0.1); padding-top:16px;}
.user-chip{font-size:0.88rem; color:#fff; margin-bottom:8px;}
.user-chip span{display:block; font-size:0.76rem; color:#8FA6A8; text-transform:uppercase; letter-spacing:0.04em; margin-top:2px;}
.logout-link{font-size:0.85rem; color:#8FA6A8;}
.logout-link:hover{color:#fff;}

.content{padding:36px 44px; max-width:1080px;}
.page-head{display:flex; align-items:center; justify-content:space-between; margin-bottom:26px; flex-wrap:wrap; gap:14px;}
.page-head p{margin-top:4px;}

.btn{display:inline-block; padding:10px 18px; border-radius:4px; font-size:0.92rem; font-weight:500; border:1px solid var(--accent); background:var(--accent); color:#fff; cursor:pointer;}
.btn:hover{background:var(--accent-dark); border-color:var(--accent-dark);}
.btn-ghost{background:transparent; color:var(--ink); border:1px solid var(--line);}
.btn-ghost:hover{border-color:var(--accent); color:var(--accent);}
.btn-danger{background:var(--danger); border-color:var(--danger);}
.btn-danger:hover{background:#943824; border-color:#943824;}
.btn-sm{padding:6px 12px; font-size:0.85rem;}

.panel{background:var(--panel); border:1px solid var(--line); border-radius:6px; padding:22px;}
table{width:100%; border-collapse:collapse;}
th,td{text-align:left; padding:12px 10px; border-bottom:1px solid var(--line); font-size:0.91rem;}
th{color:var(--muted); font-weight:500; font-size:0.8rem; text-transform:uppercase; letter-spacing:0.03em;}
tr:last-child td{border-bottom:none;}
.row-actions{display:flex; gap:8px;}

.badge{display:inline-block; padding:3px 10px; border-radius:20px; font-size:0.77rem; font-weight:500;}
.badge-ok{background:var(--ok-bg); color:var(--accent-dark);}
.badge-warn{background:var(--warn-bg); color:var(--warn);}
.badge-danger{background:var(--danger-bg); color:var(--danger);}

.stats{display:grid; grid-template-columns:repeat(4,1fr); gap:16px; margin-bottom:28px;}
.stat{background:var(--panel); border:1px solid var(--line); border-radius:6px; padding:18px 20px; border-left:4px solid var(--accent);}
.stat.warn{border-left-color:var(--warn);}
.stat.danger{border-left-color:var(--danger);}
.stat .value{font-size:1.5rem; font-weight:700;}
.stat .label{color:var(--muted); font-size:0.84rem; margin-top:4px;}

.form-grid{display:grid; grid-template-columns:1fr 1fr; gap:18px;}
.field{margin-bottom:16px;}
.field.full{grid-column:1 / -1;}
.field label{display:block; font-size:0.85rem; font-weight:500; margin-bottom:6px; color:var(--muted);}
.field input, .field select, .field textarea{width:100%; padding:10px 12px; border:1px solid var(--line); border-radius:4px; font-family:inherit; font-size:0.94rem; background:#fff; color:var(--ink);}
.field input:focus, .field select:focus, .field textarea:focus{outline:2px solid var(--accent); outline-offset:1px; border-color:var(--accent);}
.checkbox-row{display:flex; align-items:center; gap:8px; font-size:0.9rem; color:var(--ink);}
.checkbox-row input{width:auto;}
.form-actions{display:flex; gap:10px; margin-top:8px;}

.flash{padding:12px 16px; border-radius:4px; margin-bottom:20px; font-size:0.9rem;}
.flash.success{background:var(--ok-bg); color:var(--accent-dark); border:1px solid #C4DBD8;}
.flash.error{background:var(--danger-bg); color:var(--danger); border:1px solid #EBC7BC;}

.empty{color:var(--muted); padding:30px 0; text-align:center;}

/* login */
.login-screen{min-height:100vh; display:flex; align-items:center; justify-content:center; background:var(--bg);}
.login-card{background:var(--panel); border:1px solid var(--line); border-radius:8px; padding:40px; width:100%; max-width:360px;}

/* POS */
.pos-grid{display:grid; grid-template-columns:1fr 340px; gap:24px;}
.cart-line{display:flex; justify-content:space-between; padding:10px 0; border-bottom:1px solid var(--line); font-size:0.9rem;}
.cart-total{display:flex; justify-content:space-between; padding-top:14px; font-weight:700; font-size:1.05rem;}

@media (max-width:900px){
  .app{grid-template-columns:1fr;}
  .sidebar{flex-direction:row; align-items:flex-start; overflow-x:auto;}
  .sidebar nav{flex-direction:row; align-items:flex-start;}
  .nav-group{position:relative;}
  .nav-group .nav-sub{
    position:absolute; top:100%; left:0; z-index:10; min-width:180px;
    background:var(--sidebar); border:1px solid rgba(255,255,255,0.12); border-radius:4px;
    padding:6px; margin-top:4px;
  }
  .nav-sub a{border-left:none;}
  .sidebar-bottom{display:flex; align-items:center; gap:14px; border-top:none; padding-top:0; margin-left:auto;}
  .content{padding:24px;}
  .stats{grid-template-columns:1fr 1fr;}
  .form-grid{grid-template-columns:1fr;}
  .pos-grid{grid-template-columns:1fr;}
}