:root{
    --paper:#EFF2EE;
    --paper-alt:#E3E8E1;
    --panel:#FBFCFA;
    --ink:#1E2530;
    --ink-soft:#5B6270;
    --line:#D6DAD2;
    --line-soft:#E4E7E1;
    --garnet:#7C2D3F;
    --garnet-dark:#5E212F;
    --gold:#B8892B;
    --gold-dark:#966E20;
    --teal:#2F6F63;
    --teal-dark:#234f46;
    --indigo:#3B4B6B;
    --danger:#B23A48;
    --radius:10px;
    --row-h:8px;
    --font-display:'Fraunces', Georgia, serif;
    --font-body:'Manrope', -apple-system, sans-serif;
    --font-mono:'IBM Plex Mono', 'Courier New', monospace;
  }
  *{box-sizing:border-box;}
  html{-webkit-text-size-adjust:100%;}
  body{
    margin:0;
    background:var(--paper);
    color:var(--ink);
    font-family:var(--font-body);
    line-height:1.5;
    padding-bottom:60px;
  }
  a{color:var(--garnet);}
  .wrap{max-width:1120px;margin:0 auto;padding:0 20px;}

  /* Header */
  header.top{
    border-bottom:1px solid var(--line);
    background:linear-gradient(180deg, var(--panel), var(--paper));
  }
  .top-inner{
    display:flex;flex-wrap:wrap;gap:16px;align-items:flex-end;justify-content:space-between;
    padding:28px 0 18px;
  }
  .brand-eyebrow{
    font-family:var(--font-mono);font-size:11px;letter-spacing:.14em;text-transform:uppercase;
    color:var(--garnet);margin:0 0 4px;
  }
  h1{
    font-family:var(--font-display);font-weight:700;font-style:italic;
    font-size:clamp(1.6rem,4vw,2.35rem);margin:0;color:var(--ink);letter-spacing:-.01em;
  }
  .tagline{color:var(--ink-soft);font-size:.92rem;margin:6px 0 0;max-width:52ch;}
  .top-actions{display:flex;flex-wrap:wrap;gap:8px;}

  .btn{
    font-family:var(--font-body);font-weight:600;font-size:.82rem;
    border-radius:8px;border:1px solid transparent;padding:9px 14px;cursor:pointer;
    display:inline-flex;align-items:center;gap:6px;transition:transform .08s ease, background .15s ease, box-shadow .15s ease;
    white-space:nowrap;
  }
  .btn:active{transform:translateY(1px);}
  .btn:focus-visible{outline:2px solid var(--indigo);outline-offset:2px;}
  .btn-primary{background:var(--garnet);color:#fff;box-shadow:0 1px 2px rgba(94,33,47,.35);}
  .btn-primary:hover{background:var(--garnet-dark);}
  .btn-ghost{background:transparent;border-color:var(--line);color:var(--ink-soft);}
  .btn-ghost:hover{border-color:var(--ink-soft);color:var(--ink);}
  .btn-teal{background:var(--teal);color:#fff;}
  .btn-teal:hover{background:var(--teal-dark);}
  .btn-danger{background:transparent;border-color:var(--danger);color:var(--danger);}
  .btn-danger:hover{background:var(--danger);color:#fff;}
  .btn-sm{padding:5px 9px;font-size:.72rem;border-radius:6px;}
  .btn[disabled]{opacity:.45;cursor:not-allowed;}

  /* Steps nav */
  nav.steps{
    display:flex;gap:2px;padding:14px 0 0;overflow-x:auto;
  }
  .step-btn{
    font-family:var(--font-body);background:none;border:none;cursor:pointer;
    display:flex;align-items:center;gap:9px;padding:10px 16px;color:var(--ink-soft);
    border-bottom:2px solid transparent;white-space:nowrap;font-size:.88rem;font-weight:600;
  }
  .step-num{
    width:22px;height:22px;border-radius:50%;background:var(--paper-alt);color:var(--ink-soft);
    display:flex;align-items:center;justify-content:center;font-family:var(--font-mono);font-size:11px;
    flex-shrink:0;
  }
  .step-btn.active{color:var(--ink);border-bottom-color:var(--garnet);}
  .step-btn.active .step-num{background:var(--garnet);color:#fff;}
  .step-btn:hover:not(.active){color:var(--ink);}

  main{padding-top:26px;}
  .panel{display:none;animation:fade .18s ease;}
  .panel.active{display:block;}
  @keyframes fade{from{opacity:0;transform:translateY(3px);}to{opacity:1;transform:none;}}

  h2.panel-title{
    font-family:var(--font-display);font-weight:600;font-size:1.35rem;margin:0 0 4px;
  }
  p.panel-sub{color:var(--ink-soft);font-size:.9rem;margin:0 0 20px;max-width:62ch;}

  .card{
    background:var(--panel);border:1px solid var(--line);border-radius:var(--radius);
    padding:18px 20px;
  }
  .grid-2{display:grid;grid-template-columns:1fr 1fr;gap:18px;}
  @media (max-width:820px){.grid-2{grid-template-columns:1fr;}}

  label{font-size:.78rem;font-weight:600;color:var(--ink-soft);display:block;margin-bottom:4px;}
  input[type=text],input[type=number],input[type=time],select{
    font-family:var(--font-body);font-size:.88rem;padding:8px 10px;border:1px solid var(--line);
    border-radius:7px;background:#fff;color:var(--ink);width:100%;
  }
  input:focus-visible,select:focus-visible,button:focus-visible{outline:2px solid var(--indigo);outline-offset:1px;}

  /* Config table */
  .table-scroll{overflow-x:auto;-webkit-overflow-scrolling:touch;}
  table.cfg{width:100%;border-collapse:collapse;font-size:.88rem;}
  table.cfg th{text-align:left;font-family:var(--font-mono);font-size:.7rem;text-transform:uppercase;
    letter-spacing:.06em;color:var(--ink-soft);padding:6px 8px;border-bottom:1px solid var(--line);}
  table.cfg td{padding:8px;border-bottom:1px solid var(--line-soft);vertical-align:middle;}
  table.cfg td.day-name{font-weight:600;}
  table.cfg input[type=time]{width:110px;}
  .switch{position:relative;width:38px;height:22px;display:inline-block;}
  .switch input{opacity:0;width:0;height:0;}
  .slider{position:absolute;inset:0;background:var(--paper-alt);border-radius:20px;cursor:pointer;transition:.15s;border:1px solid var(--line);}
  .slider::before{content:"";position:absolute;width:16px;height:16px;left:2px;top:2px;background:#fff;border-radius:50%;transition:.15s;box-shadow:0 1px 2px rgba(0,0,0,.25);}
  .switch input:checked + .slider{background:var(--teal);border-color:var(--teal);}
  .switch input:checked + .slider::before{transform:translateX(16px);}

  /* Students layout */
  .student-list{list-style:none;margin:0;padding:0;display:flex;flex-direction:column;gap:6px;max-height:420px;overflow-y:auto;}
  .student-row{
    display:flex;align-items:center;gap:8px;padding:8px 10px;border-radius:8px;border:1px solid transparent;cursor:pointer;
  }
  .student-row:hover{background:var(--paper-alt);}
  .student-row.selected{background:#fff;border-color:var(--line);box-shadow:0 1px 3px rgba(0,0,0,.06);}
  .dot{width:11px;height:11px;border-radius:50%;flex-shrink:0;}
  .student-row .name{flex:1;font-size:.87rem;font-weight:600;}
  .student-row .x{background:none;border:none;color:var(--ink-soft);cursor:pointer;font-size:1rem;padding:2px 6px;border-radius:5px;}
  .student-row .x:hover{color:var(--danger);background:var(--paper-alt);}
  .add-row{display:flex;gap:8px;margin-top:12px;flex-wrap:wrap;}
  .add-row input{flex:1 1 140px;min-width:0;}

  .empty-hint{color:var(--ink-soft);font-size:.85rem;padding:24px 10px;text-align:center;border:1px dashed var(--line);border-radius:8px;}

  /* Availability grid */
  .avail-head{display:flex;justify-content:space-between;align-items:center;flex-wrap:wrap;gap:10px;margin-bottom:10px;}
  .mode-toggle{display:inline-flex;border:1px solid var(--line);border-radius:8px;overflow:hidden;flex-shrink:0;}
  .mode-toggle .mode-btn{font-family:var(--font-body);font-weight:600;font-size:.76rem;padding:6px 12px;border:none;background:#fff;color:var(--ink-soft);cursor:pointer;}
  .mode-toggle .mode-btn+.mode-btn{border-left:1px solid var(--line);}
  .mode-toggle .mode-btn.active[data-mode="unavail"]{background:var(--garnet);color:#fff;}
  .mode-toggle .mode-btn.active[data-mode="preferred"]{background:var(--gold);color:#fff;}
  .avail-scroll{overflow-x:auto;border:1px solid var(--line);border-radius:8px;}
  table.avail{border-collapse:collapse;font-family:var(--font-mono);font-size:9px;width:100%;min-width:420px;}
  table.avail th{background:var(--paper-alt);padding:6px 4px;font-weight:600;position:sticky;top:0;text-align:center;}
  table.avail td.time-label{color:var(--ink-soft);text-align:right;padding-right:8px;width:52px;border-right:1px solid var(--line);white-space:nowrap;line-height:1;}
  table.avail td.cell{width:60px;height:var(--row-h);padding:0;border-bottom:1px solid var(--line-soft);border-right:1px solid var(--line-soft);}
  .cell button{width:100%;height:100%;border:none;background:#DCEAE3;cursor:pointer;display:block;min-height:var(--row-h);}
  .cell button:hover{background:#c8ddd2;}
  .cell button.unavail{background:var(--garnet);}
  .cell button.unavail:hover{background:var(--garnet-dark);}
  .cell button.preferred{background:var(--gold);}
  .cell button.preferred:hover{background:var(--gold-dark);}
  .cell.closed{background:repeating-linear-gradient(45deg,var(--paper-alt),var(--paper-alt) 4px,var(--panel) 4px,var(--panel) 8px);}
  tr.hour-line td{border-top:1px solid var(--line);}
  tr.qtr-line td{border-top:1px dashed var(--line-soft);}
  .legend{display:flex;gap:16px;align-items:center;font-size:.78rem;color:var(--ink-soft);margin-top:10px;flex-wrap:wrap;}
  .legend span{display:inline-flex;align-items:center;gap:6px;}

  /* Instant hover tooltip (no native title-attribute delay) */
  .hover-tip{
    position:fixed;z-index:100;pointer-events:none;
    background:var(--ink);color:#fff;font-family:var(--font-mono);font-size:.72rem;
    padding:3px 7px;border-radius:5px;white-space:nowrap;box-shadow:0 2px 6px rgba(0,0,0,.25);
  }
  .sw{width:12px;height:12px;border-radius:3px;display:inline-block;}

  /* Lessons */
  .cours-stats{font-size:.85rem;color:var(--ink-soft);margin:-8px 0 16px;}
  .cours-stats strong{color:var(--ink);}
  .lesson-form{display:grid;grid-template-columns:1.3fr 1fr;gap:16px;}
  @media (max-width:700px){.lesson-form{grid-template-columns:1fr;}}
  .field{margin-bottom:12px;}
  .checks{display:flex;flex-direction:column;gap:6px;max-height:190px;overflow-y:auto;border:1px solid var(--line);border-radius:7px;padding:8px;background:#fff;}
  .check-row{display:flex;align-items:center;gap:8px;font-size:.85rem;}
  .check-row input{width:auto;}
  .lesson-form-actions{display:flex;gap:8px;}
  .lesson-form-actions .btn{flex:1;justify-content:center;}

  .lesson-list{list-style:none;margin:18px 0 0;padding:0;display:flex;flex-direction:column;gap:8px;}
  .lesson-item{
    display:flex;align-items:center;gap:10px;padding:10px 12px;border-radius:8px;border:1px solid var(--line);background:#fff;
  }
  .lesson-item .bar{width:5px;align-self:stretch;border-radius:3px;}
  .lesson-item .info{flex:1;min-width:0;}
  .lesson-item .lname{font-weight:700;font-size:.88rem;}
  .lesson-item .lmeta{font-size:.76rem;color:var(--ink-soft);font-family:var(--font-mono);}
  .lesson-item .lactions{display:flex;gap:6px;flex-shrink:0;}
  .lesson-item.editing{border-color:var(--gold);box-shadow:0 0 0 1px var(--gold);}

  /* Planning */
  .planning-top{display:flex;justify-content:space-between;align-items:center;gap:12px;flex-wrap:wrap;margin-bottom:16px;}
  .planning-actions{display:flex;align-items:center;gap:10px;flex-wrap:wrap;}
  .planning-actions .hint{font-size:.78rem;color:var(--ink-soft);}
  .summary{font-size:.85rem;color:var(--ink-soft);}
  .summary strong{color:var(--ink);}
  .planning-layout{display:grid;grid-template-columns:1fr 260px;gap:18px;align-items:start;}
  @media (max-width:920px){.planning-layout{grid-template-columns:1fr;}}

  .sched-scroll{overflow-x:auto;border:1px solid var(--line);border-radius:var(--radius);background:var(--panel);}
  .sched-grid{display:flex;min-width:560px;}
  .time-col{width:52px;flex-shrink:0;font-family:var(--font-mono);font-size:10px;color:var(--ink-soft);border-right:1px solid var(--line);}
  .time-col .head{height:40px;border-bottom:1px solid var(--line);}
  .time-col .mark{position:relative;height:0;}
  .time-col .mark span{position:absolute;right:6px;top:-6px;}
  .day-col{flex:1;min-width:105px;border-right:1px solid var(--line-soft);}
  .day-col:last-child{border-right:none;}
  .day-head{
    height:40px;display:flex;align-items:center;justify-content:center;font-weight:700;font-size:.78rem;
    border-bottom:1px solid var(--line);background:var(--paper-alt);position:sticky;top:0;
  }
  .day-body{position:relative;background-image:
      repeating-linear-gradient(to bottom, rgba(30,37,48,.14) 0 1px, transparent 1px 96px),
      repeating-linear-gradient(to bottom, rgba(30,37,48,.05) 0 1px, transparent 1px 24px);
  }
  .closed-zone{position:absolute;left:0;right:0;background:repeating-linear-gradient(45deg,var(--paper-alt),var(--paper-alt) 5px,var(--panel) 5px,var(--panel) 10px);pointer-events:none;}
  .lesson-block{
    position:absolute;left:3px;right:3px;border-radius:6px;padding:4px 6px;color:#fff;overflow:hidden;
    cursor:pointer;box-shadow:0 1px 3px rgba(0,0,0,.2);border-left:3px solid rgba(255,255,255,.6);
  }
  .lesson-block .t1{font-size:10.5px;font-weight:700;line-height:1.2;}
  .lesson-block .t2{font-size:9.5px;opacity:.9;font-family:var(--font-mono);}
  .slot-overlay{
    position:absolute;left:3px;right:3px;background:rgba(47,111,99,.22);border:2px dashed var(--teal);
    border-radius:6px;cursor:pointer;
  }
  .slot-overlay:hover{background:rgba(47,111,99,.42);}

  .side-card h3{font-family:var(--font-display);font-size:1.05rem;margin:0 0 4px;}
  .side-card .hint{font-size:.78rem;color:var(--ink-soft);margin:0 0 12px;}
  .pending-list{list-style:none;margin:0;padding:0;display:flex;flex-direction:column;gap:8px;}
  .pending-item{border:1px solid var(--line);border-radius:8px;padding:8px 10px;background:#fff;}
  .pending-item .pname{font-weight:700;font-size:.83rem;}
  .pending-item .pmeta{font-size:.74rem;color:var(--ink-soft);font-family:var(--font-mono);margin-bottom:6px;}
  .placement-banner{
    display:flex;justify-content:space-between;align-items:center;gap:10px;background:#eaf3f0;border:1px solid var(--teal);
    color:var(--teal-dark);border-radius:8px;padding:9px 12px;font-size:.82rem;margin-bottom:12px;
  }
  .ok-msg{color:var(--teal-dark);font-size:.85rem;text-align:center;padding:14px;}

  footer.credits{max-width:1120px;margin:40px auto 0;padding:0 20px;color:var(--ink-soft);font-size:.76rem;}

  @media (prefers-reduced-motion: reduce){*{animation:none !important;transition:none !important;}}

  /* ================= Responsive: tablet & phone ================= */
  @media (max-width:640px){
    .wrap{padding:0 16px;}
    body{padding-bottom:40px;}

    .top-inner{padding:20px 0 14px;gap:12px;align-items:flex-start;}
    .top-actions{width:100%;}
    .tagline{font-size:.86rem;}

    .btn{padding:8px 12px;font-size:.8rem;}
    .step-btn{padding:9px 12px;font-size:.83rem;gap:7px;}

    main{padding-top:20px;}
    h2.panel-title{font-size:1.15rem;}
    p.panel-sub{font-size:.85rem;margin-bottom:16px;}
    .card{padding:15px 16px;}

    .planning-top{margin-bottom:12px;}
    table.cfg{min-width:440px;}
  }

  @media (max-width:400px){
    .wrap{padding:0 14px;}
    .top-inner{padding:18px 0 12px;}
    h1{font-size:1.4rem;}
    .brand-eyebrow{font-size:10px;}
    .top-actions{gap:6px;}
    .top-actions .btn{padding:7px 10px;font-size:.76rem;}
    .card{padding:13px 14px;}
    .lesson-item{flex-wrap:wrap;}
    .lesson-item .lactions{margin-left:auto;}
  }

  /* Error page */
  .error-page{
    min-height:100vh;display:flex;align-items:center;justify-content:center;padding:32px 20px;
  }
  .error-card{
    max-width:460px;width:100%;text-align:center;background:var(--panel);
    border:1px solid var(--line);border-radius:var(--radius);padding:44px 32px;
  }
  .error-code{
    font-family:var(--font-mono);font-size:.78rem;letter-spacing:.14em;text-transform:uppercase;
    color:var(--garnet);margin:0 0 14px;
  }
  .error-title{
    font-family:var(--font-display);font-weight:700;font-style:italic;
    font-size:clamp(1.5rem,5vw,2rem);margin:0 0 12px;color:var(--ink);letter-spacing:-.01em;
  }
  .error-msg{color:var(--ink-soft);font-size:.92rem;margin:0 0 26px;line-height:1.6;}
  .error-actions{display:flex;justify-content:center;gap:10px;flex-wrap:wrap;}
  @media (max-width:420px){
    .error-card{padding:32px 22px;border-radius:8px;}
    .error-code{font-size:.72rem;letter-spacing:.1em;}
    .error-msg{font-size:.88rem;}
    .error-actions{flex-direction:column;}
    .error-actions .btn{width:100%;justify-content:center;}
  }