/* ================= case-study pages ================= */
.case-hero{padding:56px 0 24px}
.case-hero h1{margin:14px 0 18px;font-weight:800;letter-spacing:-.03em;line-height:1;font-size:clamp(2.4rem,8vw,4.8rem);max-width:16ch;text-wrap:balance}
:lang(vi) .case-hero h1{line-height:1.08}
.case-hero .lede{margin:0;max-width:44ch}
.case-hero .count{display:inline-block}
.stats{display:grid;gap:14px;margin-top:34px;grid-template-columns:1fr}
@media (min-width:700px){.stats{grid-template-columns:repeat(3,1fr)}}
.stat{border:2px solid var(--line);border-radius:22px;padding:16px 18px;background:var(--paper-2);box-shadow:4px 4px 0 var(--shadow)}
.stat:first-child{background:var(--sticker);color:var(--on-sticker)}
.stat b{display:block;font-size:clamp(1.8rem,5vw,2.4rem);letter-spacing:-.03em;line-height:1.1}
.stat span{font-size:.95rem}

.case-how-head{display:flex;align-items:flex-end;justify-content:space-between;gap:12px;margin-bottom:22px}
.play{font:inherit;font-weight:700;font-size:.92rem;cursor:pointer;border:2px solid var(--line);border-radius:999px;padding:8px 16px;background:var(--paper-2);color:var(--ink);margin-bottom:.4em}
.case-grid{display:grid;gap:22px}
@media (min-width:980px){.case-grid{grid-template-columns:minmax(0,1.15fr) minmax(0,1fr);align-items:start}}

/* ---- stage ---- */
.stage{position:relative;border:2px solid var(--line);border-radius:28px;background:var(--paper-2);box-shadow:6px 6px 0 var(--shadow);padding:22px;min-height:360px;overflow:hidden;
  background-image:radial-gradient(color-mix(in srgb,var(--ink) 10%,transparent) 1px,transparent 1.2px);background-size:16px 16px}
.stage [data-from],.stage [data-only]{opacity:0;transform:translateY(10px) scale(.97);transition:opacity .45s ease,transform .45s cubic-bezier(.16,1,.3,1)}
.stage .in{opacity:1;transform:none}
@media (prefers-reduced-motion:reduce){.stage [data-from],.stage [data-only]{transition:none}}
.sk-title{display:block;font-size:.8rem;font-weight:700;opacity:.7;margin-bottom:4px}
.pill{display:inline-block;font-size:.8rem;font-weight:700;padding:3px 10px;border-radius:999px;border:2px solid var(--line);background:var(--mint);color:var(--on-sticker);white-space:nowrap}
.pill.warn{background:var(--lemon)}
.pill.ok{background:var(--mint)}

/* ---- flow (step list) ---- */
.flow{list-style:none;margin:0;padding:0;display:grid;gap:10px}
.flow-step button{all:unset;box-sizing:border-box;cursor:pointer;display:grid;grid-template-columns:auto 1fr;column-gap:12px;width:100%;padding:14px 16px;border:2px solid var(--line);border-radius:18px;background:var(--paper-2);color:var(--ink);position:relative;overflow:hidden}
.flow-step button:focus-visible{outline:3px solid var(--tangerine);outline-offset:3px}
.flow-step .n{grid-row:span 2;display:grid;place-items:center;width:32px;height:32px;border-radius:50%;border:2px solid var(--line);font-weight:800;background:var(--paper)}
.flow-step b{font-size:1.05rem;letter-spacing:-.01em;line-height:1.3}
.flow-step .d{display:none;margin-top:4px;color:var(--ink-soft);font-size:.95rem;line-height:1.5}
.flow-step.on button{background:var(--sticker);color:var(--on-sticker);box-shadow:4px 4px 0 var(--shadow)}
.flow-step.on .d{display:block;color:inherit}
.flow-step.on .n,.flow-step.done .n{background:var(--ink);color:var(--paper)}
.flow.tick .flow-step.on button::after{content:"";position:absolute;left:0;bottom:0;height:4px;background:var(--ink);animation:dwell var(--dwell,3.4s) linear forwards}
@keyframes dwell{from{width:0}to{width:100%}}
@media (prefers-reduced-motion:reduce){.flow-step .d{display:block}}

/* ---- text ---- */
.wrap.narrow{max-width:820px}
.case-text p{font-size:1.1rem;line-height:1.65;margin:0 0 16px;max-width:64ch}
.case-text h2.big{margin-top:44px;margin-bottom:16px}
.case-text h2.big:first-child{margin-top:0}
.results{margin:0;padding:0;list-style:none;display:grid;gap:10px}
.results li{padding:14px 18px 14px 46px;border:2px solid var(--line);border-radius:18px;background:var(--paper-2);position:relative;font-size:1.03rem}
.results li::before{content:"";position:absolute;left:16px;top:18px;width:16px;height:16px;border-radius:50%;background:var(--sticker);border:2px solid var(--line)}
.stack-row{display:flex;flex-wrap:wrap;gap:8px}
.stack-row span{font-weight:600;font-size:.92rem;padding:6px 12px;border-radius:10px;border:2px solid var(--line);background:var(--paper-2)}
.next{display:block;margin-top:48px;text-decoration:none;border:2px solid var(--line);border-radius:24px;padding:20px 22px;background:var(--sticker);color:var(--on-sticker);box-shadow:5px 5px 0 var(--shadow);transition:transform .15s,box-shadow .15s}
.next:hover{transform:translate(-2px,-2px);box-shadow:7px 7px 0 var(--shadow)}
.next span{display:block;font-weight:600}
.next b{font-size:1.5rem;letter-spacing:-.02em}

/* ================= scene: packing camera ================= */
.pk{display:grid;gap:14px;grid-template-columns:1fr 1fr;grid-template-areas:"cam snap" "table snap" "order ticket"}
.pk-cam{grid-area:cam;position:relative;height:96px}
.cam-body{width:84px;height:48px;border:2px solid var(--line);border-radius:12px;background:var(--ink);position:relative}
.cam-body::after{content:"";position:absolute;right:-14px;top:12px;width:20px;height:20px;border-radius:50%;border:2px solid var(--line);background:var(--sky)}
.rec{position:absolute;left:8px;top:14px;font-size:.7rem;font-weight:800;color:#fff;display:flex;align-items:center;gap:4px}
.rec::before{content:"";width:8px;height:8px;border-radius:50%;background:var(--tangerine);animation:recblink 1.2s infinite}
@keyframes recblink{50%{opacity:.2}}
.cam-beam{position:absolute;left:70px;top:44px;width:90px;height:60px;background:linear-gradient(160deg,color-mix(in srgb,var(--sky) 45%,transparent),transparent);clip-path:polygon(0 0,30% 0,100% 100%,40% 100%)}
.pk-tag{display:inline-block;margin-top:6px;font-size:.78rem;font-weight:700;opacity:.7}
.pk-cam .pk-tag{position:absolute;left:0;bottom:0}
.pk-table{grid-area:table;border-bottom:6px solid var(--line);display:flex;align-items:flex-end;padding:0 10px;min-height:96px;
  background:repeating-linear-gradient(90deg,transparent 0 18px,color-mix(in srgb,var(--ink) 8%,transparent) 18px 20px)}
.parcel{width:110px;height:76px;background:#D9A066;border:2px solid var(--line);border-radius:6px 6px 0 0;position:relative;animation:slide 6s ease-in-out infinite}
@keyframes slide{0%,100%{transform:translateX(0)}50%{transform:translateX(30px)}}
@media (prefers-reduced-motion:reduce){.parcel{animation:none}}
.label{position:absolute;left:12px;top:12px;width:70px;height:44px;background:#fff;border:1.5px solid var(--line);border-radius:3px;display:flex;gap:4px;padding:5px}
.bars{display:block;flex:1;background:repeating-linear-gradient(90deg,#1B1A3A 0 2px,transparent 2px 3px,#1B1A3A 3px 4px,transparent 4px 6px)}
.qr{display:block;width:30px;background:
  linear-gradient(#1B1A3A,#1B1A3A) 0 0/9px 9px no-repeat,linear-gradient(#1B1A3A,#1B1A3A) 100% 0/9px 9px no-repeat,linear-gradient(#1B1A3A,#1B1A3A) 0 100%/9px 9px no-repeat,
  repeating-conic-gradient(#1B1A3A 0 25%,#fff 0 50%) 50% 50%/6px 6px}
.pk-snap{grid-area:snap;position:relative;align-self:center}
.frame{position:relative;height:120px;border:2px solid var(--line);border-radius:10px;background:#3a3550;display:flex;gap:6px;padding:26px 30px;overflow:hidden}
.frame .bars{background:repeating-linear-gradient(90deg,#fff 0 2px,transparent 2px 3px,#fff 3px 4px,transparent 4px 6px);opacity:.9}
.frame .qr{width:56px;filter:invert(1)}
.scan{position:absolute;left:0;right:0;height:3px;background:var(--mint);box-shadow:0 0 12px var(--mint);top:20%;animation:scan 1.4s ease-in-out infinite alternate}
@keyframes scan{to{top:78%}}
.flash{position:absolute;inset:0;border-radius:10px;background:#fff;pointer-events:none;z-index:2}
.flash.in{animation:flash .6s ease-out forwards}
@keyframes flash{from{opacity:.9}to{opacity:0}}
.decoded{display:inline-block;margin-top:8px;font-size:.85rem;font-weight:700;padding:4px 8px;border-radius:8px;background:var(--ink);color:var(--paper)}
.pk-order,.pk-ticket{border:2px solid var(--line);border-radius:16px;padding:12px;background:var(--paper);display:flex;flex-direction:column;gap:8px;align-items:flex-start}
.pk-order{grid-area:order}
.pk-ticket{grid-area:ticket;background:var(--bubble);color:var(--on-sticker)}
.thumbs{display:flex;gap:5px}
.thumbs i{width:34px;height:26px;border-radius:5px;border:1.5px solid var(--line);background:#3a3550}
.thumbs i.new{background:var(--mint)}
.timeline{position:relative;width:100%;height:12px;border-radius:6px;background:rgba(27,26,58,.15)}
.timeline .win{position:absolute;left:38%;width:24%;top:0;bottom:0;border-radius:6px;background:var(--ink)}
.timeline .head{position:absolute;left:38%;top:-3px;width:4px;height:18px;background:var(--tangerine);animation:head 2.4s linear infinite}
@keyframes head{to{left:62%}}
@media (max-width:560px){.pk{grid-template-columns:1fr;grid-template-areas:"cam" "table" "snap" "order" "ticket"}}

/* ================= scene: stock sync ================= */
.sk{display:grid;gap:12px;grid-template-columns:repeat(3,1fr);grid-template-areas:"ledger map held" "chat suggest suggest" "chs chs chs"}
.sk-card{border:2px solid var(--line);border-radius:16px;padding:12px;background:var(--paper)}
.sk-ledger{grid-area:ledger}.sk-map{grid-area:map;position:relative}.sk-held{grid-area:held;align-self:center;justify-self:start}
.sk-chat{grid-area:chat}.sk-suggest{grid-area:suggest;background:var(--lemon);color:var(--on-sticker)}.sk-chs{grid-area:chs;display:grid;grid-template-columns:1fr 1fr;gap:12px}
.sk-ledger ul{list-style:none;margin:0;padding:0;font-size:.85rem}
.sk-ledger li{display:flex;justify-content:space-between;gap:6px;padding:3px 0;border-bottom:1px dashed color-mix(in srgb,var(--ink) 25%,transparent)}
.big-num{display:block;font-size:2.4rem;letter-spacing:-.04em;line-height:1}
.sk-spin{position:absolute;right:10px;top:10px;width:18px;height:18px;border-radius:50%;border:3px solid var(--sky);border-top-color:transparent;animation:spin 1.2s linear infinite}
@keyframes spin{to{transform:rotate(360deg)}}
.sk-held{border:2px solid var(--line);border-radius:999px;padding:8px 14px;background:var(--lemon);color:var(--on-sticker);display:flex;gap:8px;align-items:baseline}
.sk-held .sk-title{margin:0}
.sk-chat table{border-collapse:collapse;width:100%;font-size:.88rem;text-align:center}
.sk-chat th{font-weight:700;opacity:.7;font-size:.75rem}
.sk-chat td{font-weight:800;font-size:1.1rem}
.sk-chat td.off{color:var(--tangerine)}
.formula{font-weight:700}
.ch{border:2px solid var(--line);border-radius:16px;padding:12px;color:var(--on-sticker);display:flex;flex-direction:column;gap:2px}
.ch.shopee{background:var(--tangerine)}.ch.tiktok{background:var(--sky)}
.ch span{font-weight:700;font-size:.85rem}.ch b{font-size:1.8rem;line-height:1}.ch i{font-style:normal;font-weight:700;font-size:.8rem}
@media (max-width:560px){.sk{grid-template-columns:1fr 1fr;grid-template-areas:"ledger map" "held held" "chat chat" "suggest suggest" "chs chs"}}

/* ================= scene: AI assistants ================= */
.ai{display:grid;gap:14px}
@media (min-width:560px){.ai{grid-template-columns:1.4fr 1fr;align-items:start}}
.ai-chat{display:grid;gap:10px}
.msg{max-width:92%;padding:10px 13px;border-radius:18px;border:2px solid var(--line);font-size:.95rem;line-height:1.45}
.msg.me{justify-self:end;background:var(--sky);color:var(--on-sticker);border-bottom-right-radius:6px}
.msg.bot{justify-self:start;background:var(--lemon);color:var(--on-sticker);border-bottom-left-radius:6px}
.ai-tags{display:flex;flex-wrap:wrap;gap:6px;margin-top:8px}
.ai-ctx{display:flex;flex-wrap:wrap;gap:6px}
.ai-ctx span{font-size:.8rem;font-weight:700;padding:4px 10px;border-radius:999px;border:2px dashed var(--line)}
.ai-term{border:2px solid var(--line);border-radius:14px;padding:10px 12px;background:#1B1A3A;color:#E9E7FF}
.ai-term .sk-title{color:#B7B4DC;opacity:1}
.ai-term code{font-size:.85rem;display:block;white-space:pre-wrap;word-break:break-word}
.ai-rows{margin-top:8px;display:flex;gap:8px;align-items:center;font-size:.85rem;flex-wrap:wrap}
.ai-trace{border:2px solid var(--line);border-radius:16px;padding:12px;background:var(--paper);display:grid;gap:6px}
.bar{position:relative;height:22px;border-radius:6px;background:rgba(127,127,127,.12)}
.bar::before{content:"";position:absolute;left:var(--x);top:0;bottom:0;width:0;border-radius:6px;background:var(--ink);transition:width .9s cubic-bezier(.16,1,.3,1) .1s}
.bar.llm::before{background:var(--bubble)}.bar.tool::before{background:var(--mint)}
.ai-trace.in .bar::before{width:var(--w)}
.bar span{position:relative;z-index:1;font-size:.72rem;font-weight:700;padding-left:calc(var(--x) + 6px);line-height:22px;color:var(--ink)}
.bar:first-of-type span{color:var(--paper)}

/* ================= scene: MongoDB rolling upgrade ================= */
.mg{display:grid;gap:16px}
.mg-set{display:grid;grid-template-columns:repeat(3,1fr);gap:12px}
.node{border:2px solid var(--line);border-radius:18px;padding:12px;background:var(--paper);display:flex;flex-direction:column;align-items:flex-start;gap:4px;transition:background-color .4s,transform .4s}
.node[data-role="P"]{background:var(--sticker);color:var(--on-sticker);transform:translateY(-6px);box-shadow:4px 4px 0 var(--shadow)}
.node .role{font-size:.78rem;font-weight:700;opacity:.75}
.node .ver{font-size:clamp(1.6rem,5vw,2.3rem);letter-spacing:-.03em;line-height:1}
.node .disk{width:100%;height:10px;border-radius:5px;border:1.5px solid var(--line);background:repeating-linear-gradient(90deg,var(--ink) 0 6px,transparent 6px 9px);opacity:.35}
.node.busy{animation:busy .9s ease-in-out infinite alternate}
@keyframes busy{to{box-shadow:0 0 0 5px color-mix(in srgb,var(--tangerine) 55%,transparent)}}
@media (prefers-reduced-motion:reduce){.node.busy{animation:none;box-shadow:0 0 0 4px var(--tangerine)}}
.mg-side{display:flex;flex-wrap:wrap;gap:8px}
.mg-side .fcv{background:var(--paper-2);color:var(--ink)}
.mg-writes{border:2px solid var(--line);border-radius:16px;padding:12px;background:var(--paper)}
.spark{display:flex;align-items:flex-end;gap:4px;height:56px}
.spark i{flex:1;height:var(--h);background:var(--mint);border:1.5px solid var(--line);border-radius:4px 4px 0 0;animation:pulse 1.6s ease-in-out infinite alternate}
.spark i:nth-child(3n){animation-delay:.3s}.spark i:nth-child(3n+1){animation-delay:.6s}
@keyframes pulse{to{transform:scaleY(.8);transform-origin:bottom}}
.stage[data-step="3"] .spark i:nth-child(n+7):nth-child(-n+9){height:22%;background:var(--lemon)}
@media (prefers-reduced-motion:reduce){.spark i{animation:none}}