/* แล็บเส้นทางสั้นที่สุด — เวทีบน / แผงล่าง (จอกว้าง: ซ้าย-ขวา) */
:root{
  --sans:'IBM Plex Sans Thai','Noto Sans Thai',system-ui,-apple-system,'Segoe UI',sans-serif;
  --ink:#191a24; --muted:#6b6c7e; --line:#e6e3dc; --surface:#fff; --bg:#f5f4ef;
  --brand:#2e7d88; --brand-ink:#1f5f68; --brand-soft:#dcecee;
  --ok:#129a72; --warn:#d68a17; --danger:#e2564a;
}
*{box-sizing:border-box}
html,body{margin:0;height:100%;overflow:hidden}
body{font-family:var(--sans);color:var(--ink);background:var(--bg);display:flex;flex-direction:column;
  -webkit-font-smoothing:antialiased;user-select:none;-webkit-user-select:none}
input,textarea,select,[contenteditable]{-webkit-user-select:text;user-select:text}

#stage{position:relative;flex:1;min-height:0;background:#f2f0ea}
#webgl-canvas{width:100%;height:100%;display:block;touch-action:none}

.status{
  position:absolute;left:12px;top:12px;
  background:rgba(255,255,255,.95);border:1px solid var(--line);border-radius:12px;
  padding:8px 13px;font-size:.82rem;box-shadow:0 4px 14px rgba(25,26,36,.12);
  pointer-events:none;max-width:min(560px,calc(100% - 120px));line-height:1.5;
}
.status.ok{border-color:#bfe9da;color:#0a6b50;background:#f0fbf7}
.status.bad{border-color:#f6cdc9;color:#8f2018;background:#fdf3f2}
.status.warn{border-color:#f7e2bd;color:#7d5209;background:#fffaf0}

#panel{
  flex:none;background:var(--surface);border-top:1px solid var(--line);
  padding:12px 14px 14px;display:flex;flex-direction:column;gap:11px;max-height:54vh;overflow-y:auto;
}
.panel-head{display:flex;align-items:baseline;gap:10px}
.panel-title{font-weight:700;font-size:.92rem}
.goal{font-size:.78rem;color:var(--muted);margin-left:auto;text-align:right}
.hint{font-size:.76rem;color:var(--muted);line-height:1.55;margin:0}

.mode-row{display:flex;gap:6px}
.mode-btn{flex:1;padding:8px 4px;border-radius:9px;border:1.5px solid var(--line);background:#fff;
  font-family:inherit;font-size:.8rem;font-weight:600;cursor:pointer;color:var(--ink)}
.mode-btn.is-active{border-color:var(--brand);background:var(--brand-soft);color:var(--brand-ink)}

#path-ctl,#mst-ctl{display:flex;flex-direction:column;gap:8px}
#path-ctl[hidden],#mst-ctl[hidden]{display:none}

.pick-lab{font-size:.72rem;font-weight:700;color:var(--muted);margin:2px 0 0}
.pick-row{display:flex;flex-wrap:wrap;gap:6px}
.pick-btn{
  flex:1 1 30%;padding:8px 6px;border-radius:10px;cursor:pointer;font:inherit;font-size:.78rem;
  border:1.5px solid var(--line);background:#fff;color:var(--ink);
  display:flex;flex-direction:column;gap:2px;align-items:center;
}
.pick-btn.is-active{border-color:var(--brand);background:var(--brand-soft);color:var(--brand-ink);font-weight:600}
.pick-btn small{font-size:.66rem;opacity:.65;font-weight:400}

/* แถวเลือกเมือง — ปุ่มกลมตัวอักษรเดียว */
.node-row{display:flex;flex-wrap:wrap;gap:5px}
.node-btn{
  width:34px;height:34px;border-radius:10px;border:1.5px solid var(--line);background:#fff;
  font-family:inherit;font-size:.85rem;font-weight:700;cursor:pointer;color:var(--ink);
  display:grid;place-items:center;padding:0;
}
.node-btn.is-src{border-color:#2f6fa8;background:#e5eef7;color:#1d4d78}
.node-btn.is-dst{border-color:#c56d21;background:#fbeeda;color:#8a4a10}

.ctl-row{display:flex;gap:8px}
.ctl-row .btn{flex:1}

/* ทายเส้นทางเอง */
.guess{display:flex;flex-direction:column;gap:8px}
.guess-toggle.is-active{border-color:var(--brand);background:var(--brand-soft);color:var(--brand-ink)}
.guess-body{display:flex;flex-direction:column;gap:8px}
.guess-body[hidden]{display:none}
.guess-path{
  min-height:36px;display:flex;flex-wrap:wrap;align-items:center;gap:5px;
  background:var(--bg);border-radius:10px;padding:7px 10px;font-size:.82rem;
}
.guess-path .gp-node{font-weight:700;background:#fff;border:1px solid var(--line);border-radius:8px;padding:2px 8px}
.guess-path .gp-arrow{color:var(--muted);font-size:.75rem}
.guess-path .gp-empty{color:var(--muted);font-size:.76rem}

/* ตารางระยะที่ยืนยันแล้ว */
.dist-box{border:1px solid var(--line);border-radius:12px;overflow:hidden;background:#fff}
.dist-box:empty{display:none}
.dist-box table{width:100%;border-collapse:collapse;font-size:.73rem;font-variant-numeric:tabular-nums}
.dist-box th{background:var(--bg);color:var(--muted);font-weight:700;padding:5px 8px;text-align:right}
.dist-box th:first-child,.dist-box td:first-child{text-align:left}
.dist-box td{padding:4px 8px;text-align:right;border-top:1px solid #f1efe9}
.dist-box tr.is-settled td:first-child{color:#0a6b50;font-weight:700}
.dist-box tr.is-frontier{background:#fff8ec}
.dist-box tr.is-path td{background:#eef4fa}
.dist-box td.inf{color:var(--muted)}

.tasks{display:flex;flex-direction:column;gap:5px}
.tk-head{font-size:.78rem;font-weight:600;color:var(--muted)}
.tk-head span:last-child{background:var(--brand-soft);color:var(--brand-ink);padding:1px 8px;border-radius:999px;font-size:.72rem}
.task-list{display:flex;flex-direction:column;gap:4px}
.task-item{display:flex;align-items:center;gap:7px;font-size:.78rem;padding:6px 9px;border-radius:8px;background:var(--bg)}
.task-item.is-done{background:#e9f8f2;color:#0a6b50}
.task-check{width:16px;height:16px;border-radius:50%;border:2px solid var(--line);flex:none;display:grid;place-items:center;font-size:.6rem;color:#fff}
.task-item.is-done .task-check{background:var(--ok);border-color:var(--ok)}

.actions{display:flex;gap:8px}
.btn{padding:10px 14px;border-radius:999px;border:1px solid transparent;font-family:inherit;
  font-size:.84rem;font-weight:600;cursor:pointer;box-shadow:0 2px 6px rgba(25,26,36,.12)}
.btn:active{transform:translateY(1px)}
.btn[disabled]{opacity:.45;pointer-events:none}
.btn-ghost{background:var(--surface);border-color:var(--line);color:var(--ink)}
.btn-run{background:var(--brand);color:#fff}
.btn-submit{background:var(--ok);color:#fff;width:100%}

/* คำอธิบายสีบนฉาก */
.legend{
  position:absolute;left:16px;bottom:16px;z-index:4;
  display:flex;flex-wrap:wrap;gap:10px;padding:8px 12px;border-radius:12px;
  background:rgba(255,255,255,.9);box-shadow:0 6px 20px -10px rgba(20,24,29,.4);font-size:.78rem;
}
.legend b{display:inline-flex;align-items:center;gap:5px;font-weight:500}
.legend i{width:11px;height:11px;border-radius:50%;display:inline-block}

@media (min-width:900px){
  body{flex-direction:row}
  #panel{width:360px;max-height:none;height:100%;border-top:none;border-left:1px solid var(--line);padding:16px}
}
@media (max-width:560px){
  .status{position:static;margin:8px 12px;max-width:none}
  #stage{display:flex;flex-direction:column;min-height:44vh}
  #webgl-canvas{flex:1;min-height:180px}
  .legend{position:static;margin:0 12px 8px}
}

/* ---------- แก้แผนที่เอง ---------- */
.edit-box{display:flex;flex-direction:column;gap:7px;border:1px solid var(--line);
  border-radius:12px;padding:9px 11px;background:var(--panel-soft,rgba(255,255,255,.04))}
.box-head{display:flex;align-items:center;gap:8px;font-size:.78rem;font-weight:600;opacity:.8}
.mini-btn{margin-left:auto;border:1px solid var(--line);background:transparent;border-radius:999px;
  padding:2px 11px;font-size:.7rem;font-family:inherit;cursor:pointer;color:inherit;opacity:.75}
.mini-btn.on{border-color:var(--brand,#4fc48f);background:var(--brand,#4fc48f);color:#10131c;font-weight:700;opacity:1}
#edit-body{display:flex;flex-direction:column;gap:7px}
#edit-body[hidden]{display:none}
.edge-row{display:flex;flex-wrap:wrap;gap:4px;max-height:112px;overflow-y:auto}
.eg-btn{border:1px solid var(--line);background:transparent;border-radius:8px;padding:2px 8px;
  font-size:.7rem;font-family:ui-monospace,monospace;cursor:pointer;color:inherit}
.eg-btn.on{border-color:var(--brand,#4fc48f);background:var(--brand,#4fc48f);color:#10131c;font-weight:700}
.btn-sm{padding:5px 11px;font-size:.73rem;box-shadow:none}