:root{
  --bg:#f6f7f9; --panel:#fff; --line:#e4e7ec; --text:#1d2433; --muted:#6b7385;
  --accent:#0f6e56; --accent-soft:#e3f2ed; --danger:#c2410c; --danger-soft:#fdeee6;
  --warn:#a16207; --warn-soft:#fdf6e3; --todo:#64748b; --doing:#2563eb; --done:#0f6e56;
  --radius:10px; --shadow:0 1px 2px rgba(16,24,40,.06);
}
@media (prefers-color-scheme: dark){
  :root:not([data-theme="light"]){
    --bg:#12151b; --panel:#1a1e26; --line:#2a303b; --text:#e6e9ef; --muted:#9aa3b5;
    --accent:#3fb68f; --accent-soft:#183128; --danger:#f08a5d; --danger-soft:#3a2219;
    --warn:#e0b44f; --warn-soft:#352c16; --todo:#94a3b8; --doing:#6b9bf2; --done:#3fb68f; --shadow:none;
  }
}
:root[data-theme="dark"]{
  --bg:#12151b; --panel:#1a1e26; --line:#2a303b; --text:#e6e9ef; --muted:#9aa3b5;
  --accent:#3fb68f; --accent-soft:#183128; --danger:#f08a5d; --danger-soft:#3a2219;
  --warn:#e0b44f; --warn-soft:#352c16; --todo:#94a3b8; --doing:#6b9bf2; --done:#3fb68f; --shadow:none;
}
*{box-sizing:border-box}
[hidden]{display:none!important}
html,body{margin:0;height:100%}
body{background:var(--bg);color:var(--text);font:14px/1.45 system-ui,-apple-system,"Segoe UI",Roboto,sans-serif}
button,input,select,textarea{font:inherit;color:inherit}
button{cursor:pointer}
.brand{display:flex;align-items:center;gap:8px;font-weight:700;font-size:15px}
.brand i{width:26px;height:26px;border-radius:7px;background:var(--accent);color:#fff;display:grid;place-items:center;font-style:normal;font-size:13px}
.inp{border:1px solid var(--line);background:var(--panel);border-radius:8px;padding:6px 10px;min-width:0}
.inp:focus,.btn:focus-visible{outline:2px solid var(--accent);outline-offset:1px}
.btn{border:1px solid var(--line);background:var(--panel);border-radius:8px;padding:6px 12px;white-space:nowrap}
.btn.pri{background:var(--accent);border-color:var(--accent);color:#fff;font-weight:600}
.btn.sm{padding:4px 9px;font-size:12px}
.btn.ghost{border-color:transparent;background:none;color:var(--muted)}
.btn.danger{color:var(--danger)}
.btn:disabled{opacity:.5;cursor:default}
.err{color:var(--danger);min-height:1.2em;font-size:13px}
.hint{color:var(--muted);font-size:12px;margin:0}
/* Đăng nhập */
.auth{min-height:100%;display:grid;place-items:center;padding:16px}
.auth-box{width:min(360px,100%);background:var(--panel);border:1px solid var(--line);border-radius:14px;padding:24px;display:flex;flex-direction:column;gap:12px}
.auth-box .brand{margin-bottom:6px}
.auth-box label{display:flex;flex-direction:column;gap:4px;font-size:13px;color:var(--muted)}
.auth-box .inp{color:var(--text);padding:8px 10px}
/* Bố cục */
.app{display:grid;grid-template-columns:252px 1fr;height:100vh}
.side{background:var(--panel);border-right:1px solid var(--line);display:flex;flex-direction:column;min-height:0}
.side>.brand{padding:16px 16px 12px}
.nav{overflow:auto;padding:4px 8px 12px;flex:1}
.nav a{display:flex;align-items:center;justify-content:space-between;gap:8px;padding:7px 10px;border-radius:8px;color:inherit;text-decoration:none;cursor:pointer}
.nav a:hover{background:var(--bg)}
.nav a.on{background:var(--accent-soft);color:var(--accent);font-weight:600}
.nav a span:first-child{overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.nav .cnt{font-size:12px;color:var(--muted);flex:none}
.nav .cnt.red{color:var(--danger);font-weight:600}
.grp{margin-top:14px}
.grp>.h{display:flex;align-items:center;justify-content:space-between;padding:4px 10px;font-size:11px;letter-spacing:.06em;text-transform:uppercase;color:var(--muted);cursor:pointer;user-select:none}
.grp>.h .add{border:0;background:none;color:var(--muted);font-size:16px;line-height:1;padding:0 2px;opacity:0}
.grp>.h:hover .add,.grp>.h .add:focus{opacity:1}
.grp.closed .items{display:none}
.items a{padding-left:20px}
.side-foot{border-top:1px solid var(--line);padding:10px 12px;display:flex;flex-direction:column;gap:8px}
.side-foot .row{display:flex;gap:6px;flex-wrap:wrap}
.who{font-size:13px}
.who small{color:var(--muted)}
.main{display:flex;flex-direction:column;min-width:0;min-height:0}
.top{display:flex;align-items:center;gap:10px;padding:14px 20px;border-bottom:1px solid var(--line);background:var(--panel);flex-wrap:wrap}
.top h1{font-size:17px;margin:0;margin-right:auto;white-space:nowrap;overflow:hidden;text-overflow:ellipsis;min-width:0}
.tools{display:flex;gap:8px;flex-wrap:wrap;align-items:center}
.tools #q{width:180px}
.menu-btn{display:none}
.seg{display:inline-flex;border:1px solid var(--line);border-radius:8px;overflow:hidden}
.seg button{border:0;background:none;padding:6px 12px;color:var(--muted)}
.seg button.on{background:var(--accent-soft);color:var(--accent);font-weight:600}
.sub{display:flex;gap:6px;padding:10px 20px 0;flex-wrap:wrap}
.sub:empty{display:none}
.chip{border:1px solid var(--line);background:var(--panel);border-radius:999px;padding:3px 11px;font-size:13px;color:var(--muted)}
.chip.on{background:var(--accent-soft);border-color:transparent;color:var(--accent);font-weight:600}
.content{flex:1;overflow:auto;padding:16px 20px}
/* Bảng Kanban */
.board{display:grid;grid-template-columns:repeat(3,minmax(250px,1fr));gap:14px;align-items:start}
.col{border-radius:var(--radius);min-height:120px}
.col-h{display:flex;align-items:center;gap:8px;padding:4px 4px 10px;font-weight:600}
.dot{width:8px;height:8px;border-radius:50%;flex:none}
.dot.todo{background:var(--todo)} .dot.doing{background:var(--doing)} .dot.done{background:var(--done)}
.col-h .n{color:var(--muted);font-weight:400}
.col.drag{outline:2px dashed var(--accent);outline-offset:4px}
.quick{width:100%;margin-bottom:8px}
.card{background:var(--panel);border:1px solid var(--line);border-radius:var(--radius);padding:10px 12px;margin-bottom:8px;box-shadow:var(--shadow);cursor:pointer}
.card:hover,.card:focus-visible{border-color:var(--accent);outline:none}
.card .t{font-weight:500;margin-bottom:6px;word-break:break-word}
.card.done .t{color:var(--muted)}
.meta{display:flex;flex-wrap:wrap;gap:6px;align-items:center;font-size:12px;color:var(--muted)}
.tag{display:inline-flex;align-items:center;gap:4px;padding:1px 7px;border-radius:999px;background:var(--bg);border:1px solid var(--line);font-size:12px;white-space:nowrap}
.tag.kh{font-variant-numeric:tabular-nums}
.tag.late{background:var(--danger-soft);color:var(--danger);border-color:transparent;font-weight:600}
.tag.today,.tag.soon{background:var(--warn-soft);color:var(--warn);border-color:transparent;font-weight:600}
.tag.ok{background:var(--accent-soft);color:var(--accent);border-color:transparent}
.tag.hi{color:var(--danger);border-color:var(--danger)}
.av{width:22px;height:22px;border-radius:50%;background:var(--accent-soft);color:var(--accent);display:inline-grid;place-items:center;font-size:11px;font-weight:700;margin-left:auto;flex:none}
.av.none{background:var(--bg);color:var(--muted)}
.more{display:block;width:100%;margin-top:4px}
/* Danh sách */
.tbl-wrap{overflow:auto;border:1px solid var(--line);border-radius:var(--radius)}
table{width:100%;border-collapse:collapse;background:var(--panel)}
th,td{text-align:left;padding:9px 12px;border-bottom:1px solid var(--line);vertical-align:middle}
th{font-size:12px;color:var(--muted);font-weight:600;background:var(--bg);user-select:none;white-space:nowrap}
th[data-k]{cursor:pointer}
tr:last-child td{border-bottom:0}
tbody tr.click{cursor:pointer}
tbody tr.click:hover{background:var(--bg)}
td.num{font-variant-numeric:tabular-nums;white-space:nowrap}
.st{display:inline-flex;align-items:center;gap:6px;white-space:nowrap}
/* Tổng quan */
.stats{display:grid;grid-template-columns:repeat(4,1fr);gap:12px;margin-bottom:18px}
.stat{background:var(--panel);border:1px solid var(--line);border-radius:var(--radius);padding:14px;text-align:left}
.stat b{display:block;font-size:24px;font-variant-numeric:tabular-nums}
.stat span{color:var(--muted);font-size:12px}
.stat.red b{color:var(--danger)} .stat.amber b{color:var(--warn)}
h2{font-size:14px;margin:18px 0 10px}
.empty{color:var(--muted);padding:24px;text-align:center;border:1px dashed var(--line);border-radius:var(--radius)}
/* Ngăn chi tiết */
.scrim{position:fixed;inset:0;background:rgba(0,0,0,.25);display:none;z-index:4}
.scrim.on{display:block}
.drawer{position:fixed;top:0;right:0;height:100%;width:min(480px,100%);background:var(--panel);border-left:1px solid var(--line);transform:translateX(100%);transition:transform .18s ease;display:flex;flex-direction:column;z-index:5}
.drawer.on{transform:none}
.dh{display:flex;align-items:center;gap:8px;padding:12px 16px;border-bottom:1px solid var(--line)}
.dh .sp{margin-right:auto;color:var(--muted);font-size:12px;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.db{padding:16px;overflow:auto;flex:1;display:flex;flex-direction:column;gap:12px}
.db textarea.title{font-size:16px;font-weight:600;border:0;background:none;resize:none;padding:0;width:100%}
.db textarea.title:focus{outline:none}
.fld{display:grid;grid-template-columns:110px 1fr;align-items:center;gap:8px}
.fld>label{color:var(--muted);font-size:13px}
.fld .inp{width:100%}
.people{display:flex;flex-wrap:wrap;gap:6px}
.chk{display:flex;align-items:center;gap:8px;padding:3px 0}
.chk input[type=text]{flex:1;border:0;background:none;padding:2px 0}
.chk .x{border:0;background:none;color:var(--muted);opacity:0}
.chk:hover .x,.chk .x:focus{opacity:1}
.prog{height:4px;background:var(--bg);border-radius:4px;overflow:hidden;margin-bottom:4px}
.prog i{display:block;height:100%;background:var(--accent)}
textarea.note{width:100%;min-height:80px;resize:vertical}
.sec{border-top:1px solid var(--line);padding-top:12px}
.sec>b{display:block;margin-bottom:8px}
.cmt{padding:8px 0;border-bottom:1px solid var(--line)}
.cmt:last-of-type{border-bottom:0}
.cmt .h{font-size:12px;color:var(--muted);margin-bottom:2px}
.cmt .h b{color:var(--text)}
.cmt p{margin:0;white-space:pre-wrap;word-break:break-word}
.cmt-new{display:flex;gap:8px;margin-top:8px}
.cmt-new textarea{flex:1;min-height:38px;resize:vertical}
.act{font-size:12px;color:var(--muted);padding:3px 0}
.act b{color:var(--text);font-weight:500}
.df{padding:12px 16px;border-top:1px solid var(--line);display:flex;justify-content:space-between;gap:8px}
.saving{font-size:12px;color:var(--muted);align-self:center}
/* Quản trị */
.admin-grid{display:grid;gap:18px;max-width:900px}
.card-box{background:var(--panel);border:1px solid var(--line);border-radius:var(--radius);padding:16px}
.card-box h2{margin-top:0}
.form-row{display:flex;gap:8px;flex-wrap:wrap;margin-top:12px}
.form-row .inp{flex:1;min-width:140px}
.secret{font-family:ui-monospace,Consolas,monospace;background:var(--warn-soft);color:var(--warn);padding:8px 10px;border-radius:8px;margin-top:10px;word-break:break-all}
.toast{position:fixed;bottom:16px;left:50%;transform:translateX(-50%);background:var(--text);color:var(--bg);padding:8px 14px;border-radius:8px;font-size:13px;opacity:0;transition:opacity .2s;pointer-events:none;z-index:9;max-width:90vw}
.toast.on{opacity:1}
.toast.bad{background:var(--danger);color:#fff}
/* Màn hình nhỏ */
@media (max-width:980px){
  .board{grid-template-columns:1fr}
  .stats{grid-template-columns:repeat(2,1fr)}
}
@media (max-width:760px){
  .app{grid-template-columns:1fr}
  .side{position:fixed;inset:0 auto 0 0;width:270px;z-index:6;transform:translateX(-100%);transition:transform .18s}
  .side.on{transform:none}
  .menu-btn{display:inline-block}
  .top{padding:12px 16px}
  .tools{width:100%}
  .tools #q{flex:1;width:auto}
  .sub{padding:10px 16px 0}
  .content{padding:14px 16px}
  .hide-sm{display:none}
  .fld{grid-template-columns:90px 1fr}
}