@font-face{font-family:Noto;src:url('NotoSansArabic.ttf') format('truetype');font-weight:100 900;font-display:swap}
:root{--navy:#151342;--green:#008f75;--blue:#454ff0;--cyan:#00acd0;--muted:#667189;--line:#dae0e8;--amber:#a86d14}
*{box-sizing:border-box}body{margin:0;background:#fff;color:var(--navy);font-family:Noto,Arial,sans-serif}button,input,select{font:inherit}button,select{cursor:pointer}button{color:inherit;background:transparent;border:0}button:focus-visible,a:focus-visible,select:focus-visible,input:focus-visible,.stage-scroll:focus-visible{outline:3px solid var(--cyan);outline-offset:4px}button:hover{filter:brightness(.9)}a{color:var(--blue);text-underline-offset:4px}.film-shell{max-width:1700px;margin:auto;min-height:100dvh;display:flex;flex-direction:column;background:white}.film-shell:fullscreen{max-width:none;overflow:auto}header{height:82px;border-bottom:1px solid var(--line);display:flex;align-items:center;justify-content:space-between;padding:0 34px;gap:20px}h1{font-size:27px;line-height:1.6;margin:0;font-weight:760;letter-spacing:-.5px}.header-tools{display:flex;align-items:center;gap:22px;direction:ltr}.header-tools strong{font-size:22px}.header-tools button{color:var(--blue);font-size:16px;border-left:1px solid var(--line);padding-left:20px}.chapter-rail{max-width:1050px;width:90%;margin:10px auto 0;display:flex;align-items:start;justify-content:space-between;position:relative;min-height:59px}.chapter-rail:before{content:'';height:2px;background:var(--line);position:absolute;left:8%;right:8%;top:39px}.chapter-rail button{position:relative;font-size:15px;font-weight:660;color:var(--muted);line-height:28px;min-width:86px;padding:0 5px 20px}.chapter-rail button:after{content:'';position:absolute;bottom:1px;left:calc(50% - 6px);width:10px;height:10px;border:2px solid #aeb7c6;border-radius:50%;background:white}.chapter-rail button[aria-current=true]{color:var(--green)}.chapter-rail button[aria-current=true]:after{background:var(--green);border-color:var(--green)}.chapter-rail button.done:after{border-color:var(--green)}main{flex:1;min-width:0}.stage-scroll{overflow-x:auto;direction:ltr}.stage-scroll svg{display:block;width:100%;height:auto;max-height:calc(100dvh - 350px);min-height:390px}svg text{font-family:Noto,Arial,sans-serif;fill:var(--navy);text-anchor:middle;font-size:20px}svg .small{font-size:16px;fill:var(--muted)}svg .tiny{font-size:13px;fill:var(--muted)}svg .node-letter{font-size:33px;font-weight:700}svg .node-status{font-size:16px;font-weight:650}svg .wallet-name{font-size:21px;font-weight:650}svg .balance{font-size:31px;font-weight:750;font-variant-numeric:tabular-nums}svg .latin{font-family:Arial,sans-serif;direction:ltr}svg .link{fill:none;stroke:#c8d0dc;stroke-width:2}svg .local-block{fill:#f0f1ff;stroke:#acb5d4;stroke-width:1.5}svg .local-number{font-family:Arial,sans-serif;font-size:16px;font-weight:bold}svg .packet text{fill:white;font-size:16px;font-family:Arial,sans-serif;font-weight:700}svg .node-circle{fill:white;stroke:var(--navy);stroke-width:3}svg .mining-line{font-family:monospace;font-size:15px}svg .stage-heading{font-size:24px;font-weight:700}svg .fee{fill:var(--amber);font-size:25px;font-weight:700}.narration{text-align:center;padding:2px 6vw 12px;min-height:110px;display:flex;flex-direction:column;justify-content:center}#caption{font-size:21px;line-height:1.9;margin:4px auto;font-weight:650;max-width:1120px}#caveat{font-size:13px;line-height:1.8;color:var(--muted);margin:0 auto;max-width:1200px;min-height:24px}.transport{display:flex;align-items:center;gap:22px;padding:18px 34px 10px;border-top:1px solid var(--line)}.play{border-radius:8px;background:var(--green);color:white;padding:11px 20px;display:flex;align-items:center;justify-content:center;gap:10px;font-size:17px;min-width:138px;height:50px}.play svg{height:21px;width:21px;fill:currentColor}.icon-button{width:34px;height:42px;padding:4px;flex:none}.icon-button svg{width:25px;height:25px;fill:none;stroke:currentColor;stroke-width:2.2;stroke-linecap:round;stroke-linejoin:round}#clock{font:15px Arial,sans-serif;white-space:nowrap;font-variant-numeric:tabular-nums}.seek-wrap{flex:1;min-width:150px;align-self:center;position:relative;margin-top:16px}.seek-wrap input{width:100%;cursor:pointer;accent-color:var(--green);height:20px;display:block;margin:0}.seek-labels{display:flex;justify-content:space-between;font-size:11px;color:var(--muted);line-height:20px;margin-top:3px}.speed-label select{border:1px solid var(--line);border-radius:6px;background:white;font:16px Arial,sans-serif;color:var(--navy);padding:10px 8px}.transport button:disabled{opacity:.35;cursor:default}footer{font-size:11px;color:var(--muted);text-align:center;padding:8px 24px 14px;line-height:1.8}footer span{margin-right:16px}dialog{border:1px solid var(--line);border-radius:16px;padding:26px 32px;max-width:780px;width:calc(100% - 36px);max-height:85dvh;color:var(--navy);line-height:2;font-size:16px}dialog::backdrop{background:#15134266}.dialog-title{display:flex;align-items:center;justify-content:space-between;gap:18px}dialog h2{font-size:24px}dialog h3{font-size:19px}dialog button{color:var(--blue);font-size:16px}dialog li{margin-bottom:10px}dialog .references{font-family:Arial,sans-serif;font-size:16px;line-height:1.6}dialog .references li{margin-bottom:14px}.skip{position:absolute;top:-80px;right:20px;background:white;padding:14px;z-index:10}.skip:focus{top:10px}.sr-only{position:absolute;clip:rect(0,0,0,0);width:1px;height:1px;overflow:hidden}.mobile-hint{display:none}
.stage-scroll svg{height:calc(100dvh - 286px);max-height:760px;min-height:370px}header{height:68px}.narration{min-height:88px;padding-top:0;padding-bottom:5px}#caption{font-size:19px;line-height:1.8}svg .node-letter{font-size:40px}svg .node-status{font-size:19px}svg .small{font-size:20px}svg .tiny{font-size:16px}svg .local-number{font-size:20px}svg .wallet-name{font-size:25px}svg .balance{font-size:36px}.transport{position:sticky;bottom:0;z-index:2;background:white;box-shadow:0 -5px 20px #15134206;padding-top:12px;padding-bottom:6px}footer{padding-top:4px;padding-bottom:8px}
svg text{direction:rtl;unicode-bidi:plaintext}svg .latin,svg .mining-line{direction:ltr;unicode-bidi:embed}
@media(min-width:1600px){.stage-scroll svg{max-height:780px}}
@media(max-width:900px){header{padding:12px 20px;height:auto;min-height:76px}h1{font-size:22px}.header-tools{gap:10px}.header-tools strong{font-size:17px}.header-tools button{font-size:14px;padding-left:10px}.chapter-rail{width:96%;overflow:visible}.chapter-rail button{font-size:12px;min-width:0;flex:1}.transport{padding:14px 20px;gap:12px;flex-wrap:wrap}.seek-wrap{order:6;flex-basis:100%;margin-top:0}.speed-label{margin-left:auto}.narration{padding:5px 20px 12px}#caption{font-size:18px;line-height:1.9}#caveat{font-size:12px}.stage-scroll svg{max-height:none;min-height:0;width:100%}}
@media(max-width:650px){header{flex-wrap:wrap;gap:4px}h1{font-size:21px;flex:1;white-space:nowrap}.header-tools strong{font-size:14px}.header-tools{gap:8px}.header-tools button{font-size:12px;padding-left:8px}.chapter-rail{margin-top:8px;min-height:53px}.chapter-rail button{font-size:11px;line-height:26px}.chapter-rail:before{top:37px}.stage-scroll svg{width:1000px;height:486px;max-width:none}.stage-scroll{border-bottom:1px solid #edf0f4}.mobile-hint{display:block;font-size:11px;text-align:center;color:var(--muted);margin:4px 12px 0}.narration{min-height:152px}#caption{font-size:17px}.play{min-width:113px;padding:9px 14px;height:45px;font-size:16px}.transport{gap:9px;padding:13px 15px 7px}#clock{font-size:13px}.speed-label select{font-size:14px;padding:8px 5px}footer{font-size:10px;padding:10px 18px}.seek-labels{font-size:10px}dialog{padding:18px}dialog h2{font-size:20px}}
@media(min-width:901px) and (min-height:650px){.film-shell{height:100dvh;min-height:0}header{flex:0 0 68px}.chapter-rail{flex:0 0 59px}main{display:flex;flex-direction:column;flex:1;min-height:0}.stage-scroll{flex:1;min-height:0;overflow-y:hidden}.stage-scroll svg{height:100%;min-height:0;max-height:none}.narration{flex:0 0 auto;min-height:80px}.transport{flex:0 0 74px;position:static}footer{flex:0 0 28px}}
@media(prefers-reduced-motion:reduce){*{scroll-behavior:auto!important}}
/* v3: aligned peer links, readable local ledgers, and three differentiated miners. */
svg .peer-link{stroke:#c8d2df;stroke-width:2.2}
svg .node-letter{font-size:35px}
svg .node-status{font-size:17px;font-weight:600}
svg .miner-label{font-size:15px;fill:var(--amber);font-weight:750;paint-order:stroke;stroke:white;stroke-width:7px;stroke-linejoin:round}
svg .pending-label{font-size:17px;fill:var(--blue);font-weight:600}
svg .mining-line{font-size:18px}
svg .race-status{font-size:16px;fill:var(--muted)}
svg .tiny{font-size:17px}
@media(min-width:901px) and (min-height:650px){header{height:56px;flex-basis:56px}.chapter-rail{flex-basis:50px;min-height:50px;margin-top:6px}.chapter-rail:before{top:34px}.chapter-rail button{line-height:24px;padding-bottom:16px}.transport{flex-basis:66px;padding-top:8px;padding-bottom:6px}.narration{min-height:76px}footer{flex-basis:22px;font-size:10px}h1{font-size:25px}}
@media(max-width:900px){.stage-scroll svg{height:auto}}
@media(max-width:650px){.mobile-hint{display:flex;align-items:center;justify-content:center;gap:12px;line-height:1.7;padding:5px 0 10px}.mobile-hint span{max-width:235px}.mobile-hint button{font-size:12px;color:var(--green);font-weight:700;border-bottom:1px solid var(--green);padding:4px 1px;white-space:nowrap}.stage-scroll{min-height:255px;display:flex;align-items:center}.stage-scroll svg{width:100%;height:auto;flex:none}.stage-scroll.zoomed svg{width:1000px;height:429px}.narration{min-height:140px;padding-top:10px}.chapter-rail button{white-space:nowrap;font-size:11px}.film-shell{min-height:100dvh}.seek-labels{font-size:10px}}
/* v4: separate teaching pages, never a continuous bank-to-chain transition. */
[hidden]{display:none!important}
.page-tabs{display:flex;align-self:stretch;align-items:stretch;gap:24px;margin-inline:auto}
.page-tabs a{display:flex;align-items:center;gap:4px;text-decoration:none;color:var(--muted);font-size:16px;font-weight:650;border-bottom:3px solid transparent;padding:8px 3px;white-space:nowrap}
.page-tabs a[aria-current=page]{color:var(--green);border-bottom-color:var(--green)}
.page-tabs a:hover{color:var(--navy)}
.film-shell.lab-mode{height:auto;min-height:100dvh}
.lab-mode header{flex-shrink:0}
#nonce-lab{flex:1}
@media(max-width:1100px){.page-tabs{gap:15px}.page-tabs a{font-size:14px}header h1{font-size:22px}header{padding-inline:22px;gap:14px}.header-tools{gap:12px}}
@media(max-width:900px){header{flex-wrap:wrap}.page-tabs{order:3;flex-basis:100%;justify-content:center;min-height:49px}.chapter-rail{gap:3px}.chapter-rail button{font-size:11px}}
@media(max-width:650px){header{padding:10px 15px 0}.page-tabs{gap:26px}.page-tabs a{font-size:14px}.chapter-rail{overflow-x:auto;justify-content:start;gap:11px;padding-inline:12px;width:100%}.chapter-rail button{flex:none;font-size:11px;min-width:57px}.chapter-rail:before{display:none}.transport{position:static}}
@media(max-width:650px){header h1{font-size:clamp(17px,5.2vw,21px)}}
/* v4.2: bilingual interface. Geometry and message paths stay fixed; text direction changes. */
.language-control{display:flex;align-items:center}.language-control select{min-height:38px;border:1px solid var(--line);border-radius:7px;background:#fff;color:var(--navy);font:650 14px/1.4 Noto,Arial,sans-serif;padding:6px 28px 6px 10px}
body[data-language=en]{font-family:Noto,Arial,sans-serif}
body[data-language=en] svg text{direction:ltr;unicode-bidi:plaintext}
body[data-language=en] .narration,body[data-language=en] dialog,body[data-language=en] footer{text-align:left}
body[data-language=en] .nonce-lab,body[data-language=en] .lab-workbench,body[data-language=en] .lab-settings,body[data-language=en] .nonce-explorer,body[data-language=en] .lab-probability-lesson{direction:ltr}
body[data-language=en] .lab-output-table table{text-align:left}
body[data-language=en] .lab-setting-tip{border-right:0;border-left:3px solid var(--lab-gold);padding:2px 0 2px 12px}
body[data-language=en] .nonce-explorer-template{border-right:0;border-left:3px solid var(--lab-green)}
body[data-language=en] .nonce-explorer-current{direction:ltr;border-right:0;border-left:3px solid var(--lab-blue)}
body[data-language=en] .lab-required-prefix{text-align:left}
body[data-language=en] .skip{right:auto;left:20px}
body[data-language=en] dialog ul{padding-left:24px;padding-right:0}
@media(max-width:900px){.language-control select{font-size:12px;min-height:34px;padding-inline:8px}.header-tools{gap:8px}}
@media(max-width:650px){
  .film-shell,header,main{max-width:100%;min-width:0}
  header h1{flex:0 0 100%;white-space:normal}
  .header-tools{width:100%;max-width:100%;min-width:0;justify-content:flex-start}
  .language-control select{max-width:92px}
  .header-tools button{border-left:0;border-inline-start:1px solid var(--line);padding-left:0;padding-inline-start:8px}
  .page-tabs{width:100%;max-width:100%;min-width:0;overflow-x:auto;justify-content:flex-start;gap:26px;padding-inline:2px;scrollbar-width:none}
  .page-tabs::-webkit-scrollbar{display:none}
}