/* EduRemind — giao diện quản trị */
:root{
  --brand:#0f766e;--brand-2:#14b8a6;--brand-soft:#ccfbf1;--ink:#0f2a3d;--ink-2:#334155;--muted:#64748b;
  --bg:#f4f6f1;--surface:#fff;--line:#e2e8e4;--amber:#f59e0b;--red:#e11d48;--red-soft:#ffe4e6;--green:#16a34a;--green-soft:#dcfce7;
  --r:14px;--shadow:0 1px 2px rgba(15,42,61,.06),0 4px 16px rgba(15,42,61,.05);
  --font:'Be Vietnam Pro',system-ui,-apple-system,'Segoe UI',Roboto,sans-serif;--display:'Lexend','Be Vietnam Pro',system-ui,sans-serif;
}
*{box-sizing:border-box}
html{-webkit-text-size-adjust:100%}
body{margin:0;font:15px/1.6 var(--font);color:var(--ink);background:var(--bg)}
a{color:var(--brand)}
h1,h2{font-family:var(--display);line-height:1.25;margin:0}
h1{font-size:1.35rem;font-weight:700}
h2{font-size:1.05rem;font-weight:600;display:flex;align-items:center;gap:8px;margin-bottom:12px}
code{background:#eef2ef;padding:1px 6px;border-radius:6px;font-size:.88em}
.ic{width:18px;height:18px;flex:none;fill:none;stroke:currentColor;stroke-width:2;stroke-linecap:round;stroke-linejoin:round;vertical-align:-3px}
.muted{color:var(--muted)}.small{font-size:.85rem}
.shell{display:flex;min-height:100vh}
.side{width:256px;flex:none;background:#0f2a3d;color:#cbd5e1;display:flex;flex-direction:column;position:sticky;top:0;height:100vh;padding:18px 14px}
.brand{display:flex;align-items:center;gap:10px;color:#fff;text-decoration:none;font:700 1.1rem var(--display);padding:4px 8px 18px}
.brand small{display:block;font:500 .72rem var(--font);color:#5eead4;letter-spacing:.06em;text-transform:uppercase}
.side nav{display:flex;flex-direction:column;gap:2px}
.side nav a{display:flex;align-items:center;gap:12px;padding:10px 12px;border-radius:10px;color:#cbd5e1;text-decoration:none;font-weight:500}
.side nav a:hover{background:rgba(255,255,255,.06);color:#fff}
.side nav a.on{background:linear-gradient(90deg,rgba(20,184,166,.25),rgba(20,184,166,.08));color:#fff;box-shadow:inset 3px 0 0 #2dd4bf}
.side-foot{margin-top:auto;border-top:1px solid rgba(255,255,255,.08);padding-top:12px;font-size:.88rem}
.side-foot .school{display:flex;gap:8px;align-items:center;padding:6px 8px;color:#e2e8f0}
.link{background:none;border:0;color:#94a3b8;font:inherit;cursor:pointer;display:flex;gap:8px;align-items:center;padding:6px 8px}
.link:hover{color:#fff}
.main{flex:1;min-width:0}
.top{display:flex;align-items:center;gap:12px;padding:16px 28px;background:var(--surface);border-bottom:1px solid var(--line);position:sticky;top:0;z-index:5}
.top h1{flex:1}
.menu-btn{display:none}
.content{padding:24px 28px 48px;max-width:1180px}
.card{background:var(--surface);border:1px solid var(--line);border-radius:var(--r);padding:20px 22px;margin-bottom:18px;box-shadow:var(--shadow)}
.card.narrow{max-width:520px}
.stats{display:grid;grid-template-columns:repeat(auto-fit,minmax(200px,1fr));gap:14px;margin-bottom:18px}
.stat{background:var(--surface);border:1px solid var(--line);border-radius:var(--r);padding:16px 18px;box-shadow:var(--shadow)}
.stat .k{color:var(--muted);font-size:.85rem}
.stat b{display:block;font:700 1.9rem var(--display);color:var(--ink);margin:2px 0}
.stat small{color:var(--muted)}
.cols{display:grid;grid-template-columns:1fr 1fr;gap:18px}
.cols .card{margin:0}
.kv{list-style:none;margin:0;padding:0}
.kv li{display:flex;justify-content:space-between;gap:12px;padding:9px 0;border-bottom:1px dashed var(--line)}
.kv li:last-child{border:0}
.kv .ok{color:var(--green)}.kv .bad{color:var(--red)}
.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;border:1px solid transparent;background:var(--brand);color:#fff;font:600 .95rem var(--font);padding:10px 18px;border-radius:10px;cursor:pointer;text-decoration:none;min-height:42px;transition:background .15s,transform .05s}
.btn:hover{background:#0d6159}.btn:active{transform:translateY(1px)}
.btn.ghost{background:transparent;color:var(--ink);border-color:var(--line)}
.btn.ghost:hover{background:#eef4f2}
.btn.danger{background:transparent;color:var(--red);border-color:#fecdd3}
.btn.danger:hover{background:var(--red-soft)}
.btn.sm{padding:6px 12px;min-height:34px;font-size:.88rem}
.btn.block{width:100%}
.icon-btn{background:none;border:0;padding:8px;border-radius:10px;cursor:pointer;color:var(--ink)}
.row{display:flex;gap:10px;align-items:center;flex-wrap:wrap}
.row.between{justify-content:space-between;margin-bottom:14px}
.form label{display:flex;flex-direction:column;gap:6px;font-weight:500;font-size:.92rem;margin-bottom:14px;color:var(--ink-2)}
.form label.check{flex-direction:row;align-items:center;gap:10px;font-weight:400}
input,select,textarea{font:inherit;color:var(--ink);background:#fff;border:1px solid #cfd8d3;border-radius:10px;padding:10px 12px;min-height:42px;width:100%}
textarea{resize:vertical;line-height:1.55}
input[type=checkbox]{width:18px;height:18px;min-height:0;accent-color:var(--brand)}
input:focus,select:focus,textarea:focus{outline:none;border-color:var(--brand-2);box-shadow:0 0 0 3px rgba(20,184,166,.18)}
fieldset{border:1px solid var(--line);border-radius:12px;padding:14px 16px 4px;margin:0 0 16px}
legend{font-weight:600;padding:0 6px}
.grid2{display:grid;grid-template-columns:1fr 1fr;gap:0 14px}
.grid3{display:grid;grid-template-columns:repeat(3,1fr);gap:0 14px;align-items:start}
.inline{display:flex;gap:8px}
.hint{color:var(--muted);font-size:.86rem;font-weight:400;align-self:center}
.drop{border:2px dashed #b9d9d2;border-radius:12px;padding:14px;background:#f6fbf9}
.toolbar{display:flex;gap:10px;flex-wrap:wrap;margin-bottom:10px}
.toolbar input{flex:1;min-width:200px}
.table-wrap{overflow-x:auto;-webkit-overflow-scrolling:touch}
.table{width:100%;border-collapse:collapse;font-size:.92rem}
.table th{text-align:left;color:var(--muted);font-weight:600;font-size:.8rem;text-transform:uppercase;letter-spacing:.04em;padding:10px;border-bottom:1px solid var(--line);white-space:nowrap}
.table td{padding:12px 10px;border-bottom:1px solid var(--line);vertical-align:top}
.table tr.dim td{opacity:.55}
.table td:first-child{min-width:190px}
.table .actions{white-space:nowrap;text-align:right}
.table .actions form{display:inline-flex;gap:6px}
.empty{text-align:center;color:var(--muted);padding:28px!important}
.tag{display:inline-block;font-size:.76rem;font-weight:600;padding:2px 9px;border-radius:999px;background:#eef2ef;color:var(--ink-2)}
.tag.teal{background:var(--brand-soft);color:#115e59}.tag.green{background:var(--green-soft);color:#166534}.tag.red{background:var(--red-soft);color:#9f1239}
.tag-btn{border:1px solid var(--line);background:#fff;border-radius:999px;padding:3px 12px;font:600 .8rem var(--font);cursor:pointer;color:var(--muted)}
.tag-btn.on{background:var(--brand-soft);border-color:#99f6e4;color:#115e59}
.alert{display:block;padding:12px 14px;border-radius:12px;background:#eef6ff;color:#1e3a5f;margin-bottom:16px;border:1px solid #d6e6fb}
.alert .ic{margin-right:6px}
.alert.success{background:var(--green-soft);color:#14532d;border-color:#bbf7d0}
.alert.danger{background:var(--red-soft);color:#881337;border-color:#fecdd3}
.alert.warn{background:#fff7e6;color:#7a4a00;border-color:#fde3a7}
.pager{display:flex;gap:6px;margin-top:12px}
.pager a{padding:6px 12px;border-radius:8px;border:1px solid var(--line);text-decoration:none;color:var(--ink)}
.pager a.on{background:var(--brand);color:#fff;border-color:var(--brand)}
.results{display:flex;flex-direction:column;gap:10px}
.result{border:1px solid var(--line);border-radius:12px;padding:12px 14px;background:#fbfcfb;white-space:pre-wrap}
.result b{display:block;margin-bottom:4px}
.test-out{font-size:.92rem}
.test-out.ok{color:var(--green)}.test-out.bad{color:var(--red)}
.note{display:flex;gap:8px;color:var(--muted);font-size:.85rem;margin-top:18px}
.list{padding-left:20px}
/* trang đăng nhập / cài đặt */
.auth-page{min-height:100vh;display:grid;place-items:center;padding:24px 16px;background:radial-gradient(1200px 600px at 10% -10%,#ccfbf1 0,transparent 60%),radial-gradient(900px 500px at 110% 110%,#fde68a55 0,transparent 60%),var(--bg)}
.auth-card{width:100%;max-width:420px;background:#fff;border:1px solid var(--line);border-radius:20px;padding:30px 28px;box-shadow:0 20px 60px rgba(15,42,61,.12)}
.auth-card.wide{max-width:680px}
.auth-card h1{margin:8px 0 4px}
.auth-brand{display:flex;align-items:center;gap:10px;font:700 1.15rem var(--display)}
.checks{display:flex;flex-wrap:wrap;gap:6px;margin:14px 0}
.chip{font-size:.8rem;padding:3px 10px;border-radius:999px}
.chip.ok{background:var(--green-soft);color:#166534}.chip.bad{background:var(--red-soft);color:#9f1239}
@media (max-width:900px){
  .cols{grid-template-columns:1fr}
  .side{position:fixed;left:0;top:0;z-index:20;transform:translateX(-100%);transition:transform .2s;box-shadow:0 0 40px rgba(0,0,0,.3)}
  .side.open{transform:none}
  .menu-btn{display:inline-flex}
  .top{padding:12px 16px}
  .content{padding:16px}
  .grid2,.grid3{grid-template-columns:1fr}
  .top .btn span{display:none}
}
@media (max-width:520px){.top .btn{display:none}.card{padding:16px}}