:root{
  --ink:#e8f4fb;--mut:#9ec0d4;--line:rgba(160,210,240,.22);--glass:rgba(5,22,38,.58);--glass2:rgba(8,30,50,.78);
  --acc:#5cc8f0;--acc2:#9be7d4;--warn:#ffd27a;--bad:#ff9d8a;--ok:#8be3a9;
  --gut:16px;--r:16px;
}
*{box-sizing:border-box}
html,body{margin:0;height:100%;background:#03101b;color:var(--ink);font:15px/1.5 system-ui,-apple-system,"Segoe UI",Roboto,"Helvetica Neue",Arial,sans-serif;-webkit-font-smoothing:antialiased}
body{overflow-x:hidden}
#gl{position:fixed;inset:0;width:100%;height:100%;display:block;touch-action:pan-y;background:#04121f;cursor:grab}
#gl:active{cursor:grabbing}
#scroller{height:1900vh;pointer-events:none}
.glass{background:var(--glass);border:1px solid var(--line);border-radius:var(--r);backdrop-filter:blur(14px) saturate(1.2);-webkit-backdrop-filter:blur(14px) saturate(1.2);box-shadow:0 8px 32px rgba(0,0,0,.28)}
button,select,input{font:inherit;color:inherit}
a.btn{text-decoration:none;display:inline-flex;align-items:center;color:inherit}
[hidden]{display:none!important}
.btn{background:rgba(255,255,255,.07);border:1px solid var(--line);border-radius:999px;padding:8px 14px;cursor:pointer;min-height:40px;transition:background .15s,transform .1s}
.btn:hover{background:rgba(255,255,255,.14)}.btn:active{transform:scale(.97)}
.btn.pri{background:linear-gradient(135deg,#2aa6d8,#176ea3);border-color:transparent;font-weight:600}
.btn[aria-pressed="true"]{background:rgba(92,200,240,.22);border-color:rgba(92,200,240,.6)}
button:focus-visible,select:focus-visible,input:focus-visible,a:focus-visible{outline:2px solid var(--acc2);outline-offset:2px}

.top{position:fixed;z-index:20;top:calc(10px + env(safe-area-inset-top));left:var(--gut);right:var(--gut);display:flex;gap:12px;align-items:center;justify-content:space-between;padding:8px 12px;flex-wrap:wrap}
.brand{display:flex;gap:10px;align-items:center}
.brand b{display:block;font-size:16px;letter-spacing:.2px}.brand small{display:block;color:var(--mut);font-size:12px}
.logo{display:grid;place-items:center;width:34px;height:34px;border-radius:10px;background:linear-gradient(135deg,#59d0f0,#1b78b0);font-size:22px;color:#032}
.actions{display:flex;gap:8px;flex-wrap:wrap}

.hud{padding:2px 2px 4px}
.zone{font-size:12px;letter-spacing:.14em;text-transform:uppercase;color:var(--acc2)}
.depth{font-size:56px;line-height:1;font-weight:700;font-variant-numeric:tabular-nums;margin:6px 0 0}
.depth i{font-style:normal;font-size:20px;font-weight:500;color:var(--mut);margin-left:6px}
.sub{color:var(--mut);font-size:13px;font-variant-numeric:tabular-nums}
.hud dl{margin:12px 0 8px;display:grid;gap:7px}.hud dl div{display:flex;justify-content:space-between;gap:8px;align-items:baseline}
.hud dt{color:var(--mut);font-size:12.5px}.hud dd{margin:0;font-variant-numeric:tabular-nums;text-align:right}
.hud dd small{display:block;color:var(--mut);font-size:11px}
.spec{display:grid;gap:5px;margin-top:6px}
.spec div{display:grid;grid-template-columns:30px 1fr 64px;gap:8px;align-items:center;font-size:12px}
.spec b{font-weight:500;color:var(--mut)}.spec i{display:block;height:7px;border-radius:5px;background:rgba(255,255,255,.1);overflow:hidden}
.spec u{display:block;height:100%;border-radius:5px;width:0}
.spec em{font-style:normal;text-align:right;font-variant-numeric:tabular-nums;color:var(--ink);font-size:11.5px}
#sR{background:#ff6a5a}#sG{background:#7be07e}#sB{background:#5aaeff}

.ruler{position:fixed;z-index:9;right:calc(14px + env(safe-area-inset-right));top:50%;transform:translateY(-50%);height:min(56vh,460px);display:flex;gap:6px;align-items:stretch;pointer-events:none}
.rtrack{position:relative;width:8px;border-radius:6px;background:linear-gradient(180deg,#43bff0 0%,#1b78b0 12%,#0d3d66 30%,#071f3a 52%,#030d1a 80%,#000 100%);border:1px solid var(--line)}
.rfill{position:absolute;left:0;right:0;top:0;background:rgba(255,255,255,.14);border-radius:6px}
.rmark{position:absolute;left:-5px;right:-5px;height:3px;background:#fff;border-radius:2px;box-shadow:0 0 8px #fff}
.rticks{position:relative;width:54px;font-size:10.5px;color:var(--mut)}
.rticks span{position:absolute;left:0;transform:translateY(-50%);white-space:nowrap;text-shadow:0 1px 3px #000}

.card{margin-top:12px;padding:12px 14px;border-radius:12px;background:rgba(255,255,255,.05);transition:opacity .35s}
.card.off{opacity:0}
.kicker{font-size:12px;letter-spacing:.12em;text-transform:uppercase;color:var(--acc2);display:flex;gap:10px;align-items:baseline}
.kicker b{font-size:22px;color:var(--ink);letter-spacing:0;text-transform:none}
.card p{margin:6px 0 0}.card .meta{margin-top:8px;display:flex;gap:10px;flex-wrap:wrap;font-size:12px;color:var(--mut);align-items:center}
.card .meta a{color:var(--acc);text-decoration:none;border-bottom:1px dotted var(--acc)}.card .meta a:hover{color:var(--acc2)}
.conf{display:inline-grid;place-items:center;min-width:22px;height:22px;border-radius:11px;padding:0 6px;font-weight:700}
.conf.ok{background:rgba(139,227,169,.18);color:var(--ok)}.conf.mid{background:rgba(255,210,122,.18);color:var(--warn)}
.note{font-size:12.5px;color:var(--warn);margin:6px 0 0}

.chips{padding:0}
.chips h3{margin:0 0 6px;font-size:12px;letter-spacing:.1em;text-transform:uppercase;color:var(--mut);font-weight:600}
.chips ul{list-style:none;margin:0;padding:0;display:grid;gap:6px}
.chips li{padding:6px 8px;border-radius:10px;background:rgba(255,255,255,.05);font-size:13px}
.chips li b{display:block}.chips li small{color:var(--mut);font-size:11.5px;display:block;line-height:1.35}
.chips li i{font-style:normal;float:right}
.chips li.none{color:var(--mut);background:none;padding:2px 0}

.ctl{position:fixed;z-index:25;right:var(--gut);top:calc(86px + env(safe-area-inset-top));width:min(340px,calc(100vw - 2*var(--gut)));padding:14px 16px;background:var(--glass2)}
.ctl[hidden]{display:none}
.ctl h2{margin:0 0 10px;font-size:15px}
.ctl label{display:block;margin:0 0 12px;font-size:13px;color:var(--mut)}.ctl label b{float:right;color:var(--ink);font-weight:600}
.ctl input[type=range]{width:100%;accent-color:var(--acc);margin:6px 0 2px}
.ctl small{display:block;color:var(--mut);font-size:11.5px;line-height:1.4}
.ctl .row{display:flex;gap:8px;flex-wrap:wrap;margin:6px 0}.ctl select{background:rgba(0,0,0,.35);border:1px solid var(--line);border-radius:10px;padding:8px;min-height:40px;flex:1}
.ctl .hint{margin:6px 0 10px}

.modal{position:fixed;inset:0;z-index:50;background:rgba(1,8,14,.72);display:grid;place-items:center;padding:calc(12px + env(safe-area-inset-top)) 12px 12px}
.modal[hidden]{display:none}
.sheet{position:relative;width:min(980px,100%);max-height:100%;overflow:auto;padding:22px 24px;background:var(--glass2)}
.sheet h2{margin:0 0 8px;font-size:22px}.sheet h3{margin:20px 0 6px;font-size:14px;letter-spacing:.08em;text-transform:uppercase;color:var(--acc2)}
.sheet .lead{color:var(--mut)}.sheet ul,.sheet ol{padding-left:20px;margin:6px 0}.sheet li{margin:5px 0}
.sheet a{color:var(--acc);word-break:break-word}.cols{display:grid;grid-template-columns:1fr 1fr;gap:20px}
.sheet table{width:100%;border-collapse:collapse;font-size:13.5px}.sheet td,.sheet th{padding:7px 8px;border-bottom:1px solid var(--line);text-align:left;vertical-align:top}
.sheet th{color:var(--mut);font-weight:500;font-size:12px}
.x{position:absolute;right:10px;top:8px;width:40px;height:40px;border-radius:50%;border:1px solid var(--line);background:rgba(255,255,255,.07);font-size:24px;cursor:pointer}

.hint-scroll{position:fixed;z-index:8;left:50%;transform:translateX(-50%);bottom:calc(22px + env(safe-area-inset-bottom));padding:8px 16px;border-radius:999px;background:rgba(0,0,0,.4);border:1px solid var(--line);font-size:13px;color:var(--ink);transition:opacity .6s;pointer-events:none}
.hint-scroll span{display:inline-block;animation:nod 1.4s ease-in-out infinite}.hint-scroll.off{opacity:0}
@keyframes nod{50%{transform:translateY(4px)}}
.fallback{position:fixed;inset:0;z-index:40;display:grid;place-items:center;pointer-events:none;padding:12px}
.fallback[hidden]{display:none}.fallback .glass{max-width:520px;padding:18px 22px;pointer-events:auto}
.no-gl #gl{background:linear-gradient(180deg,#2d8fc6,#0a3558 40%,#030d1a)}

@media (max-width:760px){
  :root{--gut:10px}
  .top{padding:6px 8px;flex-wrap:nowrap}
  .brand b{font-size:14px}.brand small{display:none}.logo{width:30px;height:30px;font-size:19px}
  .actions{gap:6px;flex-wrap:nowrap}.btn{padding:6px 10px;min-height:40px;min-width:40px}
  .btn .lbl{display:none}
  .depth{font-size:44px}.card{font-size:14px}
  .kicker{flex-wrap:wrap;gap:2px 8px}.kicker b{font-size:19px;white-space:nowrap}.note{font-size:12px}
  .ruler{height:30vh;right:calc(8px + env(safe-area-inset-right))}.rticks{display:none}
  .cols{grid-template-columns:1fr}.sheet{padding:16px 14px}
  .hint-scroll{bottom:auto;top:52%;font-size:12px}
}
@media (prefers-reduced-motion:reduce){.hint-scroll span{animation:none}.card{transition:none}}

.ui-off .top,.ui-off .ctl,.ui-off .guide,.ui-off .pill{display:none}
#topicLabels{position:fixed;inset:0;z-index:8;pointer-events:none;overflow:hidden}
.tlbl{position:absolute;left:0;top:0;pointer-events:auto;cursor:pointer;padding:5px 12px;border-radius:999px;background:rgba(255,214,90,.94);color:#2c1d00;border:1px solid rgba(255,255,255,.85);font-weight:700;font-size:13px;white-space:nowrap;box-shadow:0 2px 10px rgba(0,0,0,.35);transition:opacity .3s;opacity:0;visibility:hidden;max-width:min(280px,70vw);overflow:hidden;text-overflow:ellipsis}
.tlbl.on{opacity:1;visibility:visible}.tlbl:hover,.tlbl:focus-visible{background:#fff}
.lessons{position:fixed;z-index:26;left:50%;top:calc(86px + env(safe-area-inset-top));transform:translateX(-50%);width:min(560px,calc(100vw - 2*var(--gut)));max-height:calc(100vh - 110px - env(safe-area-inset-top));overflow:auto;padding:14px 16px;background:var(--glass2)}
.lessons h2{margin:0 0 4px;font-size:16px}.lessons .lead{margin:0 0 8px;color:var(--mut);font-size:13px}
.lessons ol{list-style:none;margin:0;padding:0;display:grid;gap:6px}
.lessons li button{width:100%;text-align:left;background:rgba(255,255,255,.06);border:1px solid var(--line);border-radius:12px;padding:9px 12px;cursor:pointer;min-height:44px}
.lessons li button:hover{background:rgba(255,214,90,.18);border-color:rgba(255,214,90,.6)}
.lessons li small{display:block;color:var(--mut);font-size:12px}
.reader{position:fixed;z-index:30;right:var(--gut);top:calc(80px + env(safe-area-inset-top));bottom:var(--gut);width:min(580px,calc(100vw - 2*var(--gut)));overflow:auto;padding:20px 22px 18px;background:rgba(4,22,40,.9)}
.reader .x{position:sticky;float:right;top:0;margin:-8px -10px 0 8px}
.rkick{font-size:12px;letter-spacing:.12em;text-transform:uppercase;color:#ffd65a}
.reader h2{margin:4px 0 12px;font-size:23px;line-height:1.25}
.reader article{font-size:15.5px;line-height:1.65;color:#e6f4fb}
.reader article h2{font-size:18px;margin:18px 0 6px;color:#9be7d4}.reader article h3{font-size:16px;margin:14px 0 4px}
.reader article p{margin:8px 0}.reader article ul,.reader article ol{padding-left:22px;margin:8px 0}.reader article li{margin:4px 0}
.reader article .callout{margin:12px 0;padding:10px 14px;border-radius:12px;background:rgba(255,214,90,.12);border:1px solid rgba(255,214,90,.5)}
.reader article .callout.ok{background:rgba(139,227,169,.12);border-color:rgba(139,227,169,.5)}
.reader article .table-wrap{overflow:auto;margin:10px 0}.reader article table{border-collapse:collapse;width:100%;font-size:14px}
.reader article td,.reader article th{border:1px solid var(--line);padding:6px 9px;text-align:left;vertical-align:top}.reader article th{background:rgba(255,255,255,.07)}
.reader footer{margin-top:18px;position:sticky;bottom:0;padding-top:8px;background:linear-gradient(transparent,rgba(4,22,40,.95) 40%)}
@media (max-width:760px){.reader{left:var(--gut);right:var(--gut);width:auto;top:16vh;padding:16px 14px}.reader h2{font-size:20px}.tlbl{font-size:12px;padding:4px 9px}.lessons{top:calc(64px + env(safe-area-inset-top))}}
.chip{margin-top:10px;width:100%;background:rgba(255,214,90,.14);border:1px solid rgba(255,214,90,.5);color:#ffe9a8;border-radius:999px;padding:8px 12px;min-height:40px;cursor:pointer;font-weight:600}
.chip[aria-pressed="false"]{background:rgba(255,255,255,.06);border-color:var(--line);color:var(--mut)}
.chip:hover{background:rgba(255,214,90,.24)}
.clearnote{display:block;margin-top:6px;color:var(--warn);font-size:11.5px;line-height:1.35;min-height:0}
.clearnote:empty{display:none}
#labels{position:fixed;inset:0;z-index:7;pointer-events:none;overflow:hidden}
.lbl3d{pointer-events:auto;cursor:pointer}.lbl3d:hover{background:rgba(20,70,110,.85)}
.lbl3d{position:absolute;left:0;top:0;padding:4px 10px;border-radius:999px;background:rgba(2,24,44,.66);border:1px solid rgba(150,225,255,.5);color:#f1fbff;font-size:13px;font-weight:600;white-space:nowrap;transform:translate(-50%,-100%);transition:opacity .35s;opacity:0;text-shadow:0 1px 2px #000;backdrop-filter:blur(6px);-webkit-backdrop-filter:blur(6px)}
.lbl3d.on{opacity:1}.lbl3d small{display:block;font-weight:400;font-style:italic;color:#b9e3f3;font-size:10.5px;line-height:1.2}
.chips .see{float:right;margin:0 0 0 6px;background:rgba(92,200,240,.18);border:1px solid rgba(92,200,240,.5);border-radius:999px;padding:2px 10px;font-size:12px;cursor:pointer;min-height:28px}
.chips .see:hover{background:rgba(92,200,240,.32)}
@media (max-width:760px){.lbl3d{font-size:12px;padding:3px 8px}.chip{font-size:12.5px;padding:6px 8px}}

/* ---- giao diện gọn: một chấm độ sâu + khung Hướng dẫn ---- */
.pill{position:fixed;z-index:10;left:var(--gut);top:calc(78px + env(safe-area-inset-top));display:flex;gap:6px;align-items:baseline;padding:6px 14px;border-radius:999px;cursor:pointer;color:var(--ink);min-height:40px}
.pill b{font-size:22px;font-variant-numeric:tabular-nums}.pill i{font-style:normal;color:var(--mut)}.pill span{font-size:11px;letter-spacing:.12em;text-transform:uppercase;color:var(--acc2);margin-left:4px}
.pill:hover{background:var(--glass2)}
.guide{position:fixed;z-index:27;left:var(--gut);top:calc(78px + env(safe-area-inset-top));width:min(380px,calc(100vw - 2*var(--gut)));max-height:calc(100vh - 96px - env(safe-area-inset-top));overflow:auto;padding:14px 16px 16px;background:var(--glass2)}
.guide h2{margin:0 0 10px;font-size:17px}
.guide .x{width:36px;height:36px;font-size:22px;right:10px;top:8px}
.tabs{display:flex;gap:6px;margin-bottom:12px}
.tabs button{flex:1;background:rgba(255,255,255,.06);border:1px solid var(--line);border-radius:999px;padding:7px 8px;min-height:38px;cursor:pointer;font-size:13.5px}
.tabs button[aria-selected="true"]{background:rgba(92,200,240,.24);border-color:rgba(92,200,240,.65);font-weight:600}
.steps{list-style:none;margin:0 0 12px;padding:0;display:grid;gap:8px}
.steps li{padding:9px 12px;border-radius:12px;background:rgba(255,255,255,.05);font-size:13.5px;line-height:1.5;color:var(--mut)}
.steps li b{display:block;color:var(--ink);font-size:14.5px}.steps em{font-style:normal;color:var(--acc2)}
.grow{display:flex;gap:8px;flex-wrap:wrap}.grow .btn{font-size:13.5px}
.gnote{display:block;margin-top:12px;color:var(--mut);font-size:12px;line-height:1.5}.gnote em{font-style:normal;color:var(--acc2)}
.peek{position:fixed;z-index:12;left:50%;transform:translateX(-50%);bottom:calc(16px + env(safe-area-inset-bottom));width:min(480px,calc(100vw - 2*var(--gut)));padding:14px 18px;background:var(--glass2)}
.peek h3{margin:2px 0 0;font-size:21px}.peek h3 em{display:block;font-size:13px;font-weight:400;color:var(--mut)}
.peek p{margin:6px 0 4px;color:var(--ink)}.peek .meta{display:flex;gap:10px;flex-wrap:wrap;align-items:center;font-size:12px;color:var(--mut);margin:6px 0 10px}
.peek .meta a{color:var(--acc);text-decoration:none;border-bottom:1px dotted var(--acc)}
.peek .x{width:34px;height:34px;font-size:20px}
.zenoff{position:fixed;z-index:30;right:var(--gut);bottom:calc(14px + env(safe-area-inset-bottom));background:rgba(2,16,28,.6);backdrop-filter:blur(8px);-webkit-backdrop-filter:blur(8px);opacity:.55}.zenoff:hover{opacity:1}
.zen .top,.zen .pill,.zen .guide,.zen .ctl,.zen .ruler,.zen .hint-scroll,.zen .lessons,.zen .peek{display:none!important}
.zen .tlbl,.zen .lbl3d{display:none}
@media (max-width:760px){
  .pill{top:calc(64px + env(safe-area-inset-top))}.pill span{display:none}
  .guide{top:calc(64px + env(safe-area-inset-top));max-height:calc(100vh - 80px - env(safe-area-inset-top))}
  .peek{bottom:calc(10px + env(safe-area-inset-bottom))}
}