/* Stile BitPolito (palette e componenti dalla repo silent-payments) */
:root{--bg:#f9f9f9;--fg:#001ce0;--surf:#fff;--bd:#c7cdf4;--mu:#4155e7;--soft:#eaecf7;--hov:#142ee2;--rd:#dc2626;--amb:#f59e0b;--ab:#fffbeb;--abd:#fcd34d;--at:#451a03;--sh:0 1px 2px rgba(0,28,224,.08)}
html.dark{--bg:#001ce0;--fg:#f9f9f9;--surf:#253de4;--bd:rgba(249,249,249,.3);--mu:#c7cdf4;--soft:rgba(20,46,226,.55);--hov:#e0e3f7;--ab:rgba(69,26,3,.4);--abd:rgba(245,158,11,.45);--at:#fef3c7;--sh:0 4px 12px rgba(0,0,0,.25)}
*{box-sizing:border-box}
html,body{height:100%;margin:0}
html{-webkit-text-size-adjust:100%;text-size-adjust:100%;-webkit-tap-highlight-color:transparent}
body{background:var(--bg);color:var(--fg);font-family:"Plus Jakarta Sans",system-ui,"Segoe UI",sans-serif;-webkit-font-smoothing:antialiased;transition:background .3s,color .3s}
button{font-family:inherit;touch-action:manipulation}
button:focus-visible,a:focus-visible{outline:2px solid var(--fg);outline-offset:2px}
#app{min-height:100%;height:100%;display:flex;flex-direction:column}
.wrap{width:100%;max-width:72rem;margin:0 auto;padding:0 20px}
.dk{display:none}html.dark .dk{display:block}html.dark .lt{display:none}

header{flex:none;border-bottom:1px solid var(--bd);background:var(--bg)}
.hd{display:flex;align-items:center;justify-content:space-between;padding:8px 20px}
.brand{display:flex;align-items:center;gap:12px;font-weight:700;font-size:1.1rem;letter-spacing:-.01em;text-decoration:none;color:var(--fg)}
.brand img{width:34px;height:34px}
#theme{position:relative;width:56px;height:32px;border-radius:99px;border:1px solid var(--bd);background:var(--bg);cursor:pointer;padding:0;box-shadow:var(--sh)}
#theme .knob{position:absolute;top:3px;left:3px;width:24px;height:24px;border-radius:50%;background:var(--fg);color:var(--bg);display:flex;align-items:center;justify-content:center;transition:transform .25s}
html.dark #theme .knob{transform:translateX(24px)}
.ic{display:inline-block;width:16px;height:16px;background:currentColor;-webkit-mask:center/contain no-repeat;mask:center/contain no-repeat}
.i-sun{-webkit-mask-image:url(assets/icon-sun.svg);mask-image:url(assets/icon-sun.svg)}
.i-moon{-webkit-mask-image:url(assets/icon-moon.svg);mask-image:url(assets/icon-moon.svg);display:none}
html.dark .i-sun{display:none}html.dark .i-moon{display:inline-block}
.i-heart{-webkit-mask-image:url(assets/icon-heart.svg);mask-image:url(assets/icon-heart.svg);width:16px;height:16px}

main{flex:1;min-height:0;display:flex;flex-direction:column;gap:10px;padding-top:10px;padding-bottom:6px}
.steps{flex:none;display:grid;grid-template-columns:repeat(8,1fr);gap:4px;padding:4px;border-radius:12px;border:1px solid var(--bd);background:var(--soft)}
.sb{display:flex;align-items:center;justify-content:center;gap:8px;padding:7px 4px;border:0;border-radius:8px;background:transparent;color:var(--mu);cursor:pointer;transition:.2s}
.sb.done{color:var(--fg)}
.sb.cur{background:var(--fg);color:var(--bg);box-shadow:var(--sh)}
.sb .num{flex:none;width:22px;height:22px;border-radius:50%;border:1px solid currentColor;display:flex;align-items:center;justify-content:center;font-size:11px;font-weight:700}
.sb .lbl{font-size:12px;font-weight:600;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}

.surf{background:var(--surf);border:1px solid var(--bd);border-radius:16px;box-shadow:var(--sh)}
.hero{flex:none;padding:12px 20px;min-height:12vh}
.kicker{font-size:11px;font-weight:700;letter-spacing:.14em;text-transform:uppercase;opacity:.55}
h1{margin:4px 0 0;font-size:clamp(1.5rem,2.8vw,2.3rem);line-height:1.1;letter-spacing:-.02em;transition:opacity .3s,transform .3s}
h1.sw{opacity:0;transform:translateY(8px)}
#d{margin:6px 0 0;max-width:80ch;font-size:clamp(.9rem,1.3vw,1.1rem);line-height:1.5;opacity:.88;transition:opacity .3s}
.netcard{flex:1;min-height:250px;display:flex;flex-direction:column;padding:8px 14px}
svg#net{flex:1;min-height:0;width:100%}
#panel{flex:none;min-height:40px;display:flex;flex-wrap:wrap;gap:8px;justify-content:center;align-items:center}

.nd rect{fill:var(--surf);stroke:var(--fg);stroke-width:3;transition:fill .3s,stroke .3s}
.nd.spv rect{stroke:var(--mu);stroke-dasharray:6 4}
.nd.full rect{fill:var(--fg)}
.nd text{font-size:13px;fill:var(--mu);text-anchor:middle;font-weight:600;font-family:inherit;paint-order:stroke;stroke:var(--surf);stroke-width:4px;stroke-linejoin:round}
.nd .bd{fill:var(--fg);font-size:14px;font-weight:700}
.nd{transform-box:fill-box;transform-origin:center}
.nd.hit{animation:hit .7s}.nd.bad{animation:bad .6s}
.nd.bad rect{stroke:var(--rd);fill:var(--rd)}
@keyframes hit{40%{transform:scale(1.25)}}
@keyframes bad{20%,60%{transform:translateX(-7px)}40%,80%{transform:translateX(7px)}}
line{stroke:var(--fg);stroke-opacity:.28;stroke-width:2}

.chip{border:1px solid var(--bd);background:var(--soft);color:var(--fg);border-radius:99px;padding:4px 14px;font-size:clamp(.8rem,1.2vw,1rem);font-weight:600;animation:pop2 .5s}
.chip.g{background:var(--fg);color:var(--bg);border-color:var(--fg)}
.chip.r{background:var(--ab);border-color:var(--abd);color:var(--at);border-radius:10px}
@keyframes pop2{from{opacity:0;transform:translateY(12px)}}

.lower{flex:none;display:grid;grid-template-columns:1fr 1fr;gap:12px;height:15vh;min-height:108px}
.box{position:relative;padding:8px 16px;overflow:hidden;opacity:0;transform:translateY(24px);transition:.6s}
.box.show{opacity:1;transform:none}
.box>small{font-size:11px;font-weight:700;letter-spacing:.18em;text-transform:uppercase}
#tray,#chain{position:absolute;left:16px;right:16px;top:32px;bottom:8px;overflow-x:auto;-webkit-overflow-scrolling:touch;overscroll-behavior-x:contain}
#chain{display:flex;gap:10px}
.card{position:absolute;top:0;width:70px;padding:6px;border-radius:10px;background:var(--soft);border:2px solid var(--fg);text-align:center;font-size:13px;transition:left .6s,top .7s,opacity .6s,transform .7s,border-color .3s}
.card small{display:block;color:var(--mu)}
.card.me{border-color:var(--amb);box-shadow:0 0 0 2px var(--amb)}
.blk{min-width:96px;height:64px;border-radius:10px;background:var(--fg);color:var(--bg);padding:8px 10px;font-size:12px;animation:pop .7s;flex:none}
.blk.me{outline:3px solid var(--amb)}
.blk small{display:block;opacity:.8}
@keyframes pop{from{transform:translateX(60px) scale(.4);opacity:0}}

nav.fn{flex:none;display:flex;gap:12px;justify-content:center;align-items:center;padding:8px 20px}
.btn{display:inline-flex;align-items:center;justify-content:center;gap:6px;border:2px solid;border-radius:12px;padding:10px 24px;font-size:clamp(.9rem,1.3vw,1.05rem);font-weight:600;cursor:pointer;transition:all .2s}
.btn:active{transform:scale(.98)}
.btn.o{border-color:var(--bd);background:var(--surf);color:var(--fg)}
.btn.s{border-color:var(--fg);background:var(--fg);color:var(--bg);min-width:240px}
/* hover solo su dispositivi con mouse: sul touch resterebbe "appiccicato" dopo il tap */
@media(hover:hover){.sb:hover{background:var(--surf)}.btn:hover{transform:translateY(-1px);box-shadow:var(--sh)}.btn:active{transform:none}.btn.o:hover{background:var(--soft)}.btn.s:hover{background:var(--hov);border-color:var(--hov)}html.dark .btn.s:hover{color:#001ce0}}
.btn:disabled{opacity:.45;pointer-events:none}

footer{flex:none;background:var(--soft);padding:6px 0;text-align:center;font-size:13px;font-weight:600;display:flex;gap:8px;justify-content:center;align-items:center}
footer img{height:22px;width:auto}
@media(max-width:900px){.sb .lbl{display:none}}

/* Aggiunte: nodo offline, altezza timechain, movimento ridotto */
.nd{transition:opacity .4s}
.nd.off{opacity:.3}
.nd.off rect{stroke-dasharray:3 4}
.nd .ch{font-size:11px;font-weight:600;opacity:.75}
@media(prefers-reduced-motion:reduce){*{animation-duration:.01ms!important;transition-duration:.01ms!important}}

/* ===== Responsive ===== */
/* Layout "a scorrimento": telefoni e schermi bassi (anche landscape).
   La pagina scorre normalmente e la barra dei comandi resta ancorata in basso. */
@media(max-width:640px),(max-height:640px){
 html,body{height:auto}
 #app{height:auto;min-height:100vh;min-height:100dvh}
 main{flex:1 0 auto}
 .hero{min-height:0}
 .netcard{display:block;flex:none;min-height:0}
 svg#net,svg#mk{display:block;width:100%;height:auto;max-height:70vh;margin:0 auto}
 .netcard.tree svg#net{display:none}
 .lower{height:auto}
 .box{height:116px;scroll-margin-bottom:96px}
 .blk{scroll-margin-bottom:96px}
 nav.fn{position:sticky;bottom:0;z-index:20;background:var(--bg);border-top:1px solid var(--bd);box-shadow:0 -4px 12px rgba(0,28,224,.06)}
}

/* Telefono in verticale */
@media(max-width:640px){
 .wrap{padding:0 14px}
 .hd{padding:8px 14px}
 .brand{gap:8px;font-size:1rem;min-width:0}
 .brand span{white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
 .brand img{width:30px;height:30px;flex:none}
 #theme{flex:none;margin-left:10px}
 #theme::after{content:"";position:absolute;inset:-6px} /* area di tap ~44px */
 main{gap:8px;padding-top:8px;padding-bottom:10px}
 .steps{gap:2px;padding:3px}
 .sb{min-height:44px;padding:0}
 .hero{padding:12px 14px}
 h1{font-size:1.4rem}
 #d{margin-top:4px}
 .netcard{padding:6px 4px 8px}
 svg#net,svg#mk{max-width:460px}
 #panel{gap:6px;padding:6px 4px 0;min-height:0}
 .chip{border-radius:14px;padding:5px 12px;line-height:1.3;text-align:center;max-width:100%}
 /* mempool e timechain impilate; il riquadro non ancora mostrato non occupa spazio */
 .lower{display:flex;flex-direction:column}
 .box+.box{margin-top:8px}
 .box:not(.show){height:0;margin-top:0;border-width:0;padding-top:0;padding-bottom:0;box-shadow:none}
 nav.fn{gap:8px;padding:8px 12px}
 .btn{padding:0 14px;min-height:48px;font-size:.95rem;line-height:1.15;text-align:center}
 .btn.s{flex:1;min-width:0}
 .btn.o{flex:none;width:52px;padding:0}
 .btn .tx{display:none}
 footer{padding:8px 0;flex-wrap:wrap;font-size:12px}
}

/* Albero di Merkle (passo 5) */
svg#mk{display:none;flex:1;min-height:0;width:100%}
.netcard.tree svg#net{display:none}.netcard.tree svg#mk{display:block}
#mk line{stroke-opacity:.2;stroke-width:2;transition:stroke-opacity .5s,stroke-width .5s}
#mk line.hl{stroke-opacity:1;stroke-width:3}
.mn{transition:opacity .5s}.mn.dim{opacity:.2}
.mn rect{fill:var(--surf);stroke:var(--fg);stroke-width:2;transition:fill .4s,stroke .4s}
.mn text{text-anchor:middle;fill:var(--fg);font-family:inherit;transition:fill .4s}
.mn .l{font-size:11px;font-weight:600;opacity:.75}
.mn .v{font-size:14px;font-weight:700;font-family:ui-monospace,SFMono-Regular,Menlo,Consolas,monospace}
.mn.dup rect{stroke-dasharray:5 4}
.mn.me rect,#mk .lg.me{fill:var(--ab);stroke:var(--amb);stroke-width:4}
.mn.me text{fill:var(--at)}
.mn.sib rect,.mn.ok rect,#mk .lg.sib{fill:var(--fg)}
.mn.sib text,.mn.ok text{fill:var(--bg)}
.mn.cmp rect,#mk .lg.cmp{fill:var(--soft);stroke:var(--fg);stroke-width:3}
#mk .lg{stroke-width:2}
#mk .lg.me{stroke-width:3}
#mk .lg:not(.me):not(.cmp){stroke:var(--fg)}
#mk .cp{font-size:15px;font-weight:700;fill:var(--fg);text-anchor:middle}
#mk .lt2{font-size:11px;font-weight:600;fill:var(--mu)}
/* Desktop: durante la prova di Merkle l'albero occupa tutta l'altezza e i messaggi vanno a destra */
@media(min-width:641px) and (min-height:641px){
 .netcard.tree{flex-direction:row;align-items:center;gap:16px}
 .netcard.tree svg#mk{flex:1 1 60%;height:100%}
 .netcard.tree #panel{flex:0 0 36%;flex-direction:column;align-items:stretch;justify-content:center}
 .netcard.tree .chip{text-align:center;border-radius:12px}
}