:root{
  --bg:#f4f6fa; --surface:#ffffff; --line:#e2e8f0;
  --fg:#0f172a; --muted:#64748b;
  --blue:#1d4ed8; --blue-d:#1739ab; --blue-soft:#eaf0ff;
  --red:#dc2626; --amber:#b45309;
  --r:14px; --sidebar:252px;
  --shadow:0 1px 2px rgba(15,23,42,.06), 0 4px 14px rgba(15,23,42,.05);
}
*{box-sizing:border-box}
html,body{margin:0;padding:0}
body{
  background:var(--bg); color:var(--fg);
  font:15px/1.5 -apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,"Helvetica Neue",Arial,sans-serif;
  -webkit-text-size-adjust:100%;
  overflow-x:hidden;
  padding-bottom:calc(84px + env(safe-area-inset-bottom));
}
a{color:var(--blue);text-decoration:none}
.muted{color:var(--muted)}
.center{text-align:center}
.spacer{flex:1}
[hidden]{display:none !important}

/* ---------- topbar ---------- */
.topbar{
  position:sticky;top:0;z-index:30;display:flex;align-items:center;gap:10px;
  padding:calc(10px + env(safe-area-inset-top)) 12px 10px;
  background:var(--surface);border-bottom:1px solid var(--line);
}
.brand{display:flex;align-items:center;gap:9px;min-width:0}
.brand strong{font-size:16px;white-space:nowrap;overflow:hidden;text-overflow:ellipsis;max-width:52vw}
.logo{
  display:grid;place-items:center;background:var(--blue);color:#fff;
  font-weight:800;letter-spacing:.5px;border-radius:12px;width:54px;height:54px;font-size:20px;
}
.logo.sm{width:30px;height:30px;font-size:13px;border-radius:9px}
.iconbtn{
  background:var(--surface);color:var(--fg);border:1px solid var(--line);
  border-radius:10px;min-width:38px;height:38px;font-size:17px;line-height:1;
  display:grid;place-items:center;cursor:pointer;padding:0 10px;
}
.iconbtn:active{background:var(--blue-soft)}
.menu{position:relative}
.menu summary{list-style:none}
.menu summary::-webkit-details-marker{display:none}
.menu-pop{
  position:absolute;right:0;top:44px;background:var(--surface);border:1px solid var(--line);
  border-radius:12px;min-width:190px;overflow:hidden;z-index:40;box-shadow:var(--shadow);
}
.menu-user{padding:10px 12px;border-bottom:1px solid var(--line);font-weight:700}
.menu-user small{display:block;color:var(--muted);font-weight:400}
.menu-item{display:block;padding:11px 12px;color:var(--fg)}
.menu-item:active{background:var(--blue-soft)}

/* ---------- sidebar ---------- */
.sidebar{
  position:fixed;top:0;left:0;bottom:0;width:var(--sidebar);z-index:70;
  background:var(--surface);border-right:1px solid var(--line);
  display:flex;flex-direction:column;
  padding:calc(12px + env(safe-area-inset-top)) 12px calc(12px + env(safe-area-inset-bottom));
  transform:translateX(-100%);transition:transform .22s ease;overflow-y:auto;
}
.sidebar.open{transform:none;box-shadow:var(--shadow)}
.side-head{display:flex;align-items:center;gap:9px;margin-bottom:14px}
.side-head strong{font-size:15px}
.side-close{margin-left:auto}

.nav-group{border:1px solid var(--line);border-radius:12px;overflow:hidden;margin-bottom:10px}
.nav-group>summary{
  list-style:none;display:flex;align-items:center;gap:8px;cursor:pointer;
  padding:12px;font-weight:700;font-size:14px;background:var(--surface);
}
.nav-group>summary::-webkit-details-marker{display:none}
.nav-group>summary .caret{margin-left:auto;color:var(--muted);transition:transform .18s ease;font-size:11px}
.nav-group[open]>summary{border-bottom:1px solid var(--line);background:var(--blue-soft);color:var(--blue)}
.nav-group[open]>summary .caret{transform:rotate(180deg)}
.nav-body{padding:8px}
.nav-item{
  display:flex;align-items:center;gap:9px;width:100%;text-align:left;
  background:transparent;border:none;border-radius:9px;padding:10px;
  font-size:14px;color:var(--fg);cursor:pointer;font-family:inherit;
}
.nav-item:hover{background:#f1f5fb}
.nav-item.active{background:var(--blue-soft);color:var(--blue);font-weight:700}
.dot{width:9px;height:9px;border-radius:50%;flex:0 0 auto;background:var(--blue)}
.nav-item .n{flex:1;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.nav-item .c{color:var(--muted);font-size:12px}
.nav-add{
  display:flex;align-items:center;justify-content:center;gap:6px;width:100%;
  margin-top:6px;background:var(--blue);color:#fff;border:none;border-radius:10px;
  padding:11px;font-size:14px;font-weight:700;cursor:pointer;font-family:inherit;
}
.nav-add:active{background:var(--blue-d)}
.nav-empty{color:var(--muted);font-size:13px;padding:8px 10px}
.side-foot{margin-top:auto;padding-top:12px;border-top:1px solid var(--line);font-size:12px;color:var(--muted)}
.side-backdrop{position:fixed;inset:0;background:rgba(15,23,42,.38);z-index:65}

@media(min-width:1024px){
  .sidebar{transform:none;box-shadow:none}
  .side-close,#btnSide{display:none}
  .side-backdrop{display:none !important}
  body{padding-left:var(--sidebar)}
  .topbar{padding-left:20px}
}

/* ---------- layout ---------- */
main{padding:14px 12px 10px;max-width:1200px;margin:0 auto}
.section-title{display:flex;align-items:center;gap:8px;margin:4px 0 12px;font-size:12px;color:var(--muted);text-transform:uppercase;letter-spacing:.09em;font-weight:700}

/* ---------- boards ---------- */
.board-grid{display:grid;gap:12px;grid-template-columns:1fr}
@media(min-width:620px){.board-grid{grid-template-columns:1fr 1fr}}
@media(min-width:1180px){.board-grid{grid-template-columns:repeat(3,1fr)}}
.board-card{
  background:var(--surface);color:var(--fg);border:1px solid var(--line);border-radius:var(--r);
  padding:14px;border-left:6px solid var(--blue);cursor:pointer;position:relative;box-shadow:var(--shadow);
}
.board-card h3{margin:0 0 4px;font-size:17px;padding-right:72px}
.board-card p{margin:0 0 10px;color:var(--muted);font-size:13px}
.chips{display:flex;flex-wrap:wrap;gap:6px}
.chip{background:#f1f5fb;color:var(--fg);border-radius:999px;padding:3px 10px;font-size:12px;font-weight:700}
.chip.g{background:var(--blue-soft);color:var(--blue)}
.bar{height:6px;background:#eef2f7;border-radius:999px;overflow:hidden;margin-top:10px}
.bar i{display:block;height:100%;background:var(--blue)}
.card-actions{position:absolute;top:8px;right:8px;display:flex;gap:6px}
.mini{
  background:#f1f5fb;border:1px solid var(--line);border-radius:8px;width:30px;height:30px;
  font-size:14px;cursor:pointer;color:var(--fg);display:grid;place-items:center;
}
.mini.d{background:#fef2f2;border-color:#fecaca;color:#b91c1c}

/* ---------- tabs ---------- */
.tabbar{
  display:flex;gap:8px;overflow-x:auto;padding:4px 0 10px;
  -webkit-overflow-scrolling:touch;scrollbar-width:none;
}
.tabbar::-webkit-scrollbar{display:none}
.tab{
  flex:0 0 auto;background:var(--surface);border:1px solid var(--line);color:var(--fg);
  border-radius:999px;padding:9px 16px;font-size:14px;font-weight:700;cursor:pointer;
}
.tab.active{background:var(--blue);border-color:var(--blue);color:#fff}
.tab.add{background:transparent;border-style:dashed;color:var(--muted)}

/* ---------- lists / kanban ---------- */
.lists{display:flex;gap:12px;overflow-x:auto;padding:0 12px 12px;margin:0 -12px;-webkit-overflow-scrolling:touch}
.lists::-webkit-scrollbar{height:0}
.list{
  flex:0 0 86vw;max-width:340px;background:#eef2f8;border:1px solid var(--line);
  border-radius:var(--r);padding:10px;display:flex;flex-direction:column;gap:9px;
}
@media(min-width:620px){.list{flex:0 0 320px}}
.list.drop{border-color:var(--blue);background:var(--blue-soft)}
.list-head{display:flex;align-items:center;gap:8px}
.list-head h4{margin:0;font-size:14px;flex:1;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.count{background:var(--surface);color:var(--muted);border:1px solid var(--line);border-radius:999px;padding:2px 9px;font-size:12px}

.task{
  background:var(--surface);color:var(--fg);border:1px solid var(--line);border-radius:11px;
  padding:10px 11px;display:flex;gap:9px;align-items:flex-start;cursor:grab;box-shadow:0 1px 2px rgba(15,23,42,.05);
}
.task.done{opacity:.6}
.task.done .t-title{text-decoration:line-through}
.task.dragging{opacity:.4}
.cb{
  flex:0 0 auto;width:21px;height:21px;border-radius:6px;border:2px solid #cbd5e1;
  background:#fff;display:grid;place-items:center;cursor:pointer;font-size:13px;color:#fff;padding:0;
}
.cb.on{background:var(--blue);border-color:var(--blue)}
.t-main{flex:1;min-width:0}
.t-title{font-weight:600;font-size:14px;word-break:break-word}
.t-notes{color:var(--muted);font-size:12.5px;margin-top:3px;word-break:break-word}
.t-meta{display:flex;flex-wrap:wrap;gap:5px;margin-top:7px}
.tag{font-size:11px;font-weight:700;border-radius:999px;padding:2px 8px;background:#f1f5fb;color:var(--fg)}
.tag.high{background:#fef2f2;color:#b91c1c}
.tag.low{background:#ecfeff;color:#0e7490}
.tag.due{background:#fffbeb;color:var(--amber)}
.tag.late{background:var(--red);color:#fff}
.tag.who{background:var(--blue-soft);color:var(--blue)}
.addtask{
  background:var(--surface);border:1px dashed #cbd5e1;color:var(--muted);
  border-radius:11px;padding:10px;font-size:13px;cursor:pointer;width:100%;
}
.list-add{
  flex:0 0 76vw;max-width:260px;background:var(--surface);border:1px dashed #cbd5e1;
  color:var(--muted);border-radius:var(--r);padding:16px;cursor:pointer;font-size:14px;
}
@media(min-width:620px){.list-add{flex:0 0 220px}}

/* ---------- forms ---------- */
.card{background:var(--surface);border:1px solid var(--line);border-radius:var(--r);padding:14px;box-shadow:var(--shadow)}
label{display:block;font-size:13px;color:var(--muted);margin-bottom:12px;font-weight:700}
input,textarea,select{
  width:100%;margin-top:6px;background:var(--surface);color:var(--fg);
  border:1px solid var(--line);border-radius:10px;padding:12px;font-size:15px;font-family:inherit;
}
input:focus,textarea:focus,select:focus{outline:2px solid var(--blue);outline-offset:-1px}
textarea{min-height:84px;resize:vertical}
.row{display:flex;gap:10px}
.row>*{flex:1}
.btn{
  border:1px solid var(--line);border-radius:11px;padding:13px 16px;font-size:15px;font-weight:700;
  cursor:pointer;background:#f1f5fb;color:var(--fg);font-family:inherit;
}
.btn-primary{background:var(--blue);color:#fff;border-color:var(--blue)}
.btn-primary:active{background:var(--blue-d)}
.btn-danger{background:var(--red);color:#fff;border-color:var(--red)}
.btn-block{width:100%}
.btn-row{display:flex;gap:10px;margin-top:4px}
.btn-row .btn{flex:1}

/* ---------- auth ---------- */
body.auth{display:grid;place-items:center;min-height:100vh;padding:20px}
.auth-wrap{width:100%;max-width:380px}
.brand-big{text-align:center;margin-bottom:20px}
.brand-big .logo{margin:0 auto 10px}
.brand-big h1{margin:0;font-size:24px}
.brand-big p{margin:2px 0 0;color:var(--muted)}
.auth-card{margin-bottom:14px}
.alert{background:#fef2f2;border:1px solid #fecaca;color:#b91c1c;border-radius:10px;padding:10px;margin-bottom:12px;font-size:13px}

/* ---------- sheet ---------- */
.sheet-backdrop{position:fixed;inset:0;background:rgba(15,23,42,.42);z-index:80}
.sheet{
  position:fixed;left:0;right:0;bottom:0;z-index:90;background:var(--surface);
  border-top:1px solid var(--line);border-radius:18px 18px 0 0;
  max-height:88vh;overflow:auto;padding-bottom:calc(16px + env(safe-area-inset-bottom));
  box-shadow:var(--shadow);
}
@media(min-width:620px){
  .sheet{left:50%;transform:translateX(-50%);width:460px;bottom:24px;border-radius:18px;border:1px solid var(--line)}
}
.sheet-head{
  display:flex;align-items:center;gap:10px;padding:14px 14px 10px;
  position:sticky;top:0;background:var(--surface);border-bottom:1px solid var(--line);
}
.sheet-head h2{margin:0;font-size:16px;flex:1}
.sheet-body{padding:14px}

/* ---------- misc ---------- */
.empty{text-align:center;color:var(--muted);padding:40px 16px}
.empty strong{display:block;color:var(--fg);font-size:17px;margin-bottom:6px}
.fab{
  position:fixed;right:16px;bottom:calc(18px + env(safe-area-inset-bottom));z-index:60;
  width:56px;height:56px;border-radius:50%;border:none;background:var(--blue);color:#fff;
  font-size:30px;line-height:1;cursor:pointer;box-shadow:0 6px 18px rgba(29,78,216,.35);
}
.fab:active{background:var(--blue-d)}
.toast{
  position:fixed;left:50%;transform:translateX(-50%);bottom:calc(88px + env(safe-area-inset-bottom));
  z-index:95;background:var(--fg);color:#fff;border-radius:999px;padding:10px 18px;
  font-size:13px;font-weight:700;max-width:90vw;
}
.toast.err{background:var(--red);color:#fff}