/* Pile – styles. Palette: xanh #087BEA, mực #10243d, pastel vàng/hồng/mint/lime */
:root{--blue:#087BEA;--ink:#10243d;--bg:#f3f9ff;--y:#ffe58a;--p:#ffc6dc;--m:#bff3df;--l:#dcf47e;--bl:#cfe6ff;
--f:"Nunito",ui-rounded,"SF Pro Rounded","Hiragino Maru Gothic ProN",system-ui,sans-serif;
--edge:2.5px solid var(--ink);--hard:4px 4px 0 var(--ink)}
*{box-sizing:border-box}
html{scroll-behavior:smooth;scroll-padding-top:80px}
body{margin:0;font:600 1.05rem/1.55 var(--f);color:var(--ink);background:var(--bg);overflow-x:hidden}
img{max-width:100%;height:auto}
h1,h2,h3{margin:0;line-height:1.05;font-weight:900}
h2{font-size:clamp(2rem,5vw,3.4rem);margin-bottom:1.5rem}
h3{font-size:1.25rem;margin-bottom:.35rem;line-height:1.2}
p{margin:0 0 .6rem}
:focus-visible{outline:3px solid var(--blue);outline-offset:3px;border-radius:8px}
.skip{position:absolute;left:-999px;top:8px;background:#fff;padding:.5rem 1rem;border:var(--edge);border-radius:12px;z-index:99}
.skip:focus{left:8px}

.top{position:sticky;top:0;z-index:20;display:flex;justify-content:space-between;align-items:center;padding:.7rem clamp(1rem,4vw,3rem);background:var(--bg);border-bottom:2px solid rgba(16,36,61,.08)}
.brand{display:flex;align-items:center;gap:.5rem;font-weight:900;font-size:1.5rem;color:var(--ink);text-decoration:none}
.top nav{display:flex;align-items:center;gap:1.4rem}
.top nav a:not(.btn){color:var(--ink);text-decoration:none;font-weight:800}
.top nav a:not(.btn):hover{color:var(--blue)}

.btn{display:inline-block;background:var(--blue);color:#fff;font:900 1.15rem var(--f);padding:.85rem 1.6rem;border:var(--edge);border-radius:999px;box-shadow:var(--hard);text-decoration:none;cursor:pointer;transition:transform .15s,box-shadow .15s}
.btn:hover{transform:translate(-1px,-2px) rotate(-1deg);box-shadow:5px 7px 0 var(--ink)}
.btn:active{transform:translate(3px,3px) scale(.96,.92);box-shadow:1px 1px 0 var(--ink)}
.btn.small{font-size:.95rem;padding:.5rem 1.1rem;box-shadow:3px 3px 0 var(--ink)}
.btn.big{font-size:1.4rem;padding:1.05rem 2.2rem}
.btn.ghost{background:#fff;color:var(--ink)}
.link{color:var(--ink);font-weight:800;text-underline-offset:5px;text-decoration-thickness:3px;text-decoration-color:var(--blue)}

section{padding:clamp(3rem,8vw,6rem) clamp(1rem,4vw,3rem);max-width:1180px;margin:0 auto}
.hero{display:grid;grid-template-columns:1fr 1.15fr;gap:clamp(1.5rem,4vw,3.5rem);align-items:center;padding-top:clamp(2rem,5vw,4rem)}
h1{font-size:clamp(3.4rem,9vw,6.4rem);letter-spacing:-.03em;margin-bottom:1.2rem}
.lead{font-size:clamp(1.2rem,2.4vw,1.5rem);font-weight:800;max-width:22ch}
.cta-row{display:flex;flex-wrap:wrap;align-items:center;gap:1.4rem;margin:1.6rem 0 1.2rem}
.facts{display:flex;flex-wrap:wrap;gap:.5rem;list-style:none;padding:0;margin:0}
.facts li{background:var(--y);border:2px solid var(--ink);border-radius:12px;padding:.15rem .7rem;font-size:.92rem;font-weight:800}
.facts li:nth-child(2){background:var(--m)}.facts li:nth-child(3){background:var(--p)}

/* Demo */
.desk{position:relative;background:#fff;border:var(--edge);border-radius:28px;box-shadow:6px 6px 0 var(--ink);padding:1rem 1.2rem 1.4rem;transform:rotate(.8deg);background-image:radial-gradient(#d6e8fb 1.5px,transparent 1.5px);background-size:22px 22px}
.desk-top{display:flex;align-items:flex-end;justify-content:space-between;gap:.8rem;min-height:92px}
.mascot{transform-origin:50% 100%;flex:none}
.mascot.hop{animation:hop .6s}
.bubble{position:relative;background:var(--y);border:2px solid var(--ink);border-radius:18px;padding:.5rem .9rem;font-weight:800;font-size:.95rem;margin:0;max-width:24ch}
.bubble::after{content:"";position:absolute;right:-9px;bottom:14px;width:14px;height:14px;background:var(--y);border-right:2px solid var(--ink);border-top:2px solid var(--ink);transform:rotate(45deg)}
.hint{font-size:.9rem;font-weight:700;opacity:.75;margin:.6rem 0 .2rem}
.tray{display:flex;flex-wrap:wrap;gap:.7rem;min-height:120px;padding:.6rem 0 1rem;touch-action:pan-y}
.file{--x:0px;--y:0px;--s:1;position:relative;touch-action:none;user-select:none;cursor:grab;font:800 .85rem var(--f);color:var(--ink);background:#fff;border:2px solid var(--ink);border-radius:12px;padding:.55rem .8rem .55rem 3rem;box-shadow:3px 3px 0 var(--ink);transform:translate(var(--x),var(--y)) rotate(var(--r)) scale(var(--s));z-index:1}
.file::before{content:attr(data-ext);position:absolute;left:.4rem;top:50%;translate:0 -50%;width:2.2rem;padding:.25rem 0;text-align:center;font-size:.68rem;font-weight:900;background:var(--bl);border-radius:8px}
.file[data-ext=DOC]::before{background:var(--y)}.file[data-ext=FIG]::before{background:var(--p)}.file[data-ext=JPG]::before{background:var(--m)}
.file.snap{transition:transform .4s cubic-bezier(.5,-.2,.4,1.2),opacity .4s}
.file.drag{cursor:grabbing;z-index:5;box-shadow:7px 9px 0 var(--ink)}
.file[aria-pressed=true]{background:var(--l);outline:3px solid var(--blue);outline-offset:2px}
.file.fly{opacity:0}
.folders{display:grid;grid-template-columns:repeat(3,1fr);gap:.8rem}
.folder{position:relative;display:block;height:120px;padding:0;border:0;background:none;font-family:var(--f);color:var(--ink);cursor:pointer;transition:transform .25s}
.folder .back,.folder .front{position:absolute;inset:14px 0 0;border:var(--edge);border-radius:6px 16px 16px 16px;background:var(--c)}
.folder .back::before{content:"";position:absolute;left:-2.5px;top:-14px;width:46%;height:16px;background:var(--c);border:var(--edge);border-bottom:0;border-radius:10px 10px 0 0}
.folder .back{filter:brightness(.93)}
.folder .front{top:36px;display:flex;flex-direction:column;align-items:center;justify-content:center;border-radius:14px;gap:.1rem;transform-origin:50% 100%;transition:transform .25s}
.folder .front b{font-size:1.05rem;font-weight:900}
.count{font-style:normal;font-size:.8rem;font-weight:800;background:#fff;border:2px solid var(--ink);border-radius:999px;min-width:1.7rem;padding:0 .4rem}
.paper{position:absolute;left:14%;right:14%;top:26px;height:70px;background:#fff;border:2px solid var(--ink);border-radius:8px;transition:transform .3s cubic-bezier(.3,1.5,.5,1)}
.paper.p2{left:20%;right:10%;top:30px;background:var(--bl)}
.c-yellow{--c:var(--y)}.c-pink{--c:var(--p)}.c-mint{--c:var(--m)}
.folder:hover,.folder:focus-visible,.folder.over{transform:rotate(-3deg) translateY(-4px)}
.folder:hover .p1,.folder:focus-visible .p1,.folder.over .p1{transform:translateY(-20px) rotate(-6deg)}
.folder:hover .p2,.folder:focus-visible .p2,.folder.over .p2{transform:translateY(-14px) rotate(7deg)}
.folder:hover .front,.folder.over .front{transform:rotate(1.5deg)}
.folder.catch{animation:catch .5s}
.demo-actions{display:flex;gap:.8rem;margin:1.2rem 0 .6rem}
.log{list-style:none;padding:0;margin:.5rem 0;display:grid;gap:.35rem;font-size:.92rem;font-weight:700;min-height:2.2rem}
.log s{opacity:.55}
.log .arrow{margin:0 .4rem}
.log .new{position:relative;display:inline-block;background:var(--l);border-radius:8px;padding:0 .4rem;animation:write .7s steps(18) both}
.log .new::after{content:"✎";position:absolute;right:-.2rem;top:-.3rem;font-size:1.1rem;animation:pen .7s both}
.note{font-size:.82rem;opacity:.65}
.confetti{position:absolute;left:50%;top:60%;width:10px;height:14px;border-radius:3px;background:var(--c);pointer-events:none;animation:pop 1.1s ease-out forwards;z-index:9}

/* Features */
.features h2{max-width:14ch}
.bento{display:grid;grid-template-columns:repeat(6,1fr);gap:1.2rem}
.patch{border:var(--edge);border-radius:24px;box-shadow:var(--hard);padding:1.4rem;transition:transform .2s}
.patch:hover{transform:rotate(0) translateY(-3px)}
.patch.a{grid-column:span 4;transform:rotate(-.8deg)}.patch.b{grid-column:span 2;transform:rotate(1deg)}
.patch.c{grid-column:span 2;transform:rotate(.6deg)}.patch.d{grid-column:span 4;transform:rotate(-.5deg)}
.patch.e{grid-column:span 2;transform:rotate(-1deg)}.patch.f{grid-column:span 4;display:flex;justify-content:space-between;align-items:center;gap:1rem;transform:rotate(.5deg)}
.y{background:var(--y)}.p{background:var(--p)}.m{background:var(--m)}.l{background:var(--l)}.bl{background:var(--bl)}.w{background:#fff}
.chips{display:flex;flex-wrap:wrap;gap:.5rem;margin-top:.8rem}
.chips span{background:#fff;border:2px solid var(--ink);border-radius:10px;padding:.2rem .7rem;font-weight:800;font-size:.9rem}
.chips .strike{text-decoration:line-through}
.dots{display:flex;gap:.5rem;flex:none}
.dots i{width:34px;height:34px;border:2.5px solid var(--ink);border-radius:50%}

.use-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:1.2rem}
.sub{font-size:1.2rem;margin-top:-1rem;margin-bottom:2rem}
.use{border:var(--edge);border-radius:24px;box-shadow:var(--hard);padding:1.6rem 1.4rem 2rem}
.use:nth-child(1){transform:rotate(-1.2deg)}.use:nth-child(2){transform:rotate(.8deg) translateY(10px)}.use:nth-child(3){transform:rotate(-.5deg)}
.use code{display:inline-block;margin-top:.8rem;background:#fff;border:2px solid var(--ink);border-radius:10px;padding:.2rem .7rem;font:800 .9rem var(--f)}

.steps{display:grid;grid-template-columns:repeat(3,1fr);gap:1.2rem;list-style:none;padding:0;margin:0 0 1.5rem}
.steps li{background:#fff;border:var(--edge);border-radius:24px;padding:1.4rem;box-shadow:var(--hard)}
.ico{display:flex;align-items:center;justify-content:center;gap:.4rem;height:84px;margin-bottom:1rem;border-radius:16px;background:var(--bl);font-weight:900;font-size:1.8rem}
.ico.dmg::before{content:"";width:46px;height:56px;background:#fff;border:var(--edge);border-radius:10px 10px 18px 18px;box-shadow:inset 0 -14px 0 var(--m)}
.ico.drag i{width:44px;height:44px;background:var(--blue);border:var(--edge);border-radius:12px}
.ico.drag u{width:48px;height:38px;background:var(--y);border:var(--edge);border-radius:6px 12px 12px 12px}
.ico.open{background:var(--m)}.ico.open::before{content:"";width:56px;height:56px;border-radius:16px;background:var(--blue);border:var(--edge);box-shadow:var(--hard)}
.warn{background:var(--y);border:var(--edge);border-radius:18px;padding:1rem 1.2rem;max-width:70ch}

.final{text-align:center}
.final h2{margin:.6rem 0 1.4rem}
.final p{margin-top:1.2rem}
footer{display:flex;justify-content:space-between;gap:1rem;padding:1.5rem clamp(1rem,4vw,3rem);border-top:2px solid rgba(16,36,61,.1);font-weight:700}
footer a{color:var(--ink)}

@keyframes hop{30%{transform:translateY(-22px) rotate(-6deg)}60%{transform:translateY(0) scale(1.06,.92)}80%{transform:translateY(-6px) rotate(4deg)}}
@keyframes catch{35%{transform:scale(1.07,.9)}65%{transform:scale(.97,1.05)}}
@keyframes write{from{clip-path:inset(0 100% 0 0)}to{clip-path:inset(0 -1rem 0 0)}}
@keyframes pen{from{opacity:1;right:100%}to{opacity:0;right:-.2rem}}
@keyframes pop{from{transform:translate(0,0) rotate(0)}to{transform:translate(var(--dx),var(--dy)) rotate(var(--rot));opacity:0}}

@media (max-width:860px){
 .hero{grid-template-columns:1fr}.use-grid,.steps{grid-template-columns:1fr}
 .patch.a,.patch.b,.patch.c,.patch.d,.patch.e,.patch.f{grid-column:span 6}
 .use:nth-child(n){transform:none}
}
@media (max-width:520px){.top nav a:not(.btn){display:none}.folder .front b{font-size:.9rem}.patch.f{flex-direction:column;align-items:flex-start}}
@media (prefers-reduced-motion:reduce){
 *,*::before,*::after{animation:none!important;transition:none!important;scroll-behavior:auto!important}
}