/* Shared "Press me" theme for every Computer Science World page (loaded from /cs-world/theme.css). */
  .bar-left{justify-self:start}
  .themebtn{display:inline-flex;align-items:center;gap:8px;border:1px solid var(--line);background:#fff;color:var(--ink);font-family:inherit;font-weight:800;font-size:13px;padding:9px 14px;border-radius:999px;cursor:pointer;transition:transform .15s,box-shadow .15s}
  .themebtn:hover{transform:translateY(-1px) scale(1.04);box-shadow:0 4px 14px rgba(0,0,0,0.16)}
  .themebtn:active{transform:scale(.96)}
  .themebtn .tb-ic{font-size:16px;line-height:1}
  @media(max-width:640px){.themebtn .tb-txt{display:none}.themebtn{padding:9px 11px}}
  html.ps2{--paper:#eef2fb;--ink:#0f1c47;--muted:rgba(15,28,71,0.62);--red:#f26b3a;--blue:#2c55b4;--line:rgba(15,28,71,0.14);--card:rgba(255,255,255,0.95);--shadow:0 10px 30px rgba(8,20,70,0.35)}
  html.ps2 body{background:radial-gradient(1100px 700px at 88% -8%,#5683dc 0,transparent 62%),radial-gradient(900px 650px at -5% 45%,#21449b 0,transparent 62%),#2c55b4;background-attachment:fixed}
  #themeBg{display:none;position:fixed;inset:0;z-index:-1;pointer-events:none;overflow:hidden}
  html.ps2 #themeBg{display:block}
  #themeBg span{position:absolute;font-family:'Courier New',ui-monospace,monospace;font-weight:900;line-height:1;opacity:.5;text-shadow:0 0 14px currentColor;translate:calc(var(--mx,0) * var(--k,20) * 1px) calc(var(--my,0) * var(--k,20) * 1px);animation:tbFloat var(--d,12s) ease-in-out infinite;animation-delay:var(--l,0s)}
  #themeBg canvas{position:absolute;inset:0;width:100%;height:100%}
  @keyframes tbFloat{0%,100%{transform:translateY(0) rotate(var(--r,0deg))}50%{transform:translateY(-34px) rotate(calc(var(--r,0deg) + 6deg))}}
  html.ps2 body::after{content:"";position:fixed;left:50%;top:-20vh;width:90vw;height:60vh;transform:translateX(-50%);z-index:-1;pointer-events:none;background:radial-gradient(ellipse at center,rgba(120,170,255,0.45),transparent 65%)}
  html.ps2 header{background:rgba(255,255,255,0.9);border-bottom-color:rgba(255,255,255,0.6)}
  html.ps2 .hero h1,html.ps2 #resources > h2.sec,html.ps2 .hero .tag{color:#fff;text-shadow:0 2px 14px rgba(8,20,70,0.35)}
  html.ps2 .hero h1{background:linear-gradient(180deg,#fff 30%,#bcd3ff 100%);-webkit-background-clip:text;background-clip:text;-webkit-text-fill-color:transparent;text-shadow:none;filter:drop-shadow(0 4px 18px rgba(10,30,110,0.55))}
  html.ps2 .hero .btn-lg.red{background:linear-gradient(180deg,#ff8d5a,#f26b3a);box-shadow:0 10px 30px rgba(242,107,58,0.55),inset 0 1px 0 rgba(255,255,255,0.5);animation:tbGlow 2.4s ease-in-out infinite}
  @keyframes tbGlow{0%,100%{box-shadow:0 10px 30px rgba(242,107,58,0.45),inset 0 1px 0 rgba(255,255,255,0.5)}50%{box-shadow:0 10px 44px rgba(242,107,58,0.85),inset 0 1px 0 rgba(255,255,255,0.5)}}
  html.ps2 header{background:rgba(255,255,255,0.82);backdrop-filter:blur(18px) saturate(1.4);-webkit-backdrop-filter:blur(18px) saturate(1.4);box-shadow:0 8px 30px rgba(6,16,60,0.35)}
  html.ps2 header::after{content:"";position:absolute;left:0;right:0;bottom:-1px;height:2px;background:linear-gradient(90deg,transparent,#42c79b,#a9b8f5,#f4a9d6,#f58a52,transparent)}
  html.ps2 .card,html.ps2 .rescat,html.ps2 .rec,html.ps2 .lvlbtn{border:1px solid rgba(255,255,255,0.85);box-shadow:0 16px 40px rgba(6,16,60,0.42),inset 0 1px 0 #fff}
  html.ps2 .card{transition:transform .2s,box-shadow .2s}
  html.ps2 .card:hover{transform:translateY(-5px);box-shadow:0 22px 50px rgba(6,16,60,0.55),0 0 0 2px rgba(255,255,255,0.7),inset 0 1px 0 #fff}
  html.ps2 .lvlbtn:not(.on){background:linear-gradient(180deg,#fff,#e8eefc)}
  html.ps2 .lvlbtn.on[data-level=alevel]{background:linear-gradient(180deg,#ff8d5a,#f26b3a)}
  html.ps2 .lvlbtn.on[data-level=gcse]{background:linear-gradient(180deg,#1f3a85,#0f1c47)}
  html.ps2 .salebar{box-shadow:0 8px 24px rgba(6,16,60,0.35)}
  html.ps2 .hero .tag{color:#cfe2ff}
  html.ps2 .hero p{color:rgba(255,255,255,0.88)}
  html.ps2 .hero::after{content:"コンピュータ・サイエンス";display:block;margin-top:22px;color:rgba(255,255,255,0.72);letter-spacing:.38em;font-size:13px;font-weight:700}
  html.ps2 #grid.lvl-gcse{background:rgba(255,255,255,0.14);border-color:rgba(255,255,255,0.5)}
  html.ps2 #grid.lvl-alevel{background:rgba(242,107,58,0.2);border-color:rgba(255,205,180,0.7)}
  html.ps2 .lvlbtn.on[data-level=gcse]{background:#14295f;border-color:#fff;box-shadow:0 8px 24px rgba(8,20,70,0.45)}
  html.ps2 .lvlhint{color:#fff}
  html.ps2 .card,html.ps2 .rec,html.ps2 .rescat{backdrop-filter:blur(6px);-webkit-backdrop-filter:blur(6px)}
  html.ps2 .rec::before{background:linear-gradient(90deg,#42c79b,#a9b8f5,#f4a9d6,#f58a52)}
  html.ps2 #faq > h2.sec,html.ps2 .showcase-title{color:#fff;text-shadow:0 2px 14px rgba(8,20,70,0.35)}
  html.ps2 .showcase .eyebrow{color:#cfe2ff}
  html.ps2 #faq .faq{background:rgba(255,255,255,0.95);border:none;border-radius:18px;padding:6px 22px;box-shadow:var(--shadow)}
  html.ps2 footer{color:rgba(255,255,255,0.8);border-top-color:rgba(255,255,255,0.3)}
  html.ps2 footer a{color:#fff}
  /* the pop: a circular wipe from the button, then the four symbols bounce in */
  .themepop{position:fixed;inset:0;z-index:9999;pointer-events:none;background:#2c55b4;clip-path:circle(0 at var(--x,40px) var(--y,30px));display:grid;place-items:center;align-content:center;gap:26px}
  .themepop.tp-light{background:#f3f2f2}
  .themepop.tp-go{animation:tpWipe .7s cubic-bezier(.7,0,.2,1) forwards,tpOut .55s 2.55s ease forwards}
  @keyframes tpWipe{to{clip-path:circle(150% at var(--x,40px) var(--y,30px))}}
  @keyframes tpOut{to{opacity:0}}
  .themepop .syms{display:flex;gap:clamp(14px,4vw,42px)}
  .themepop .sym{width:clamp(54px,11vw,104px);height:clamp(54px,11vw,104px);opacity:0;transform:scale(0) rotate(-50deg)}
  .themepop.tp-go .sym{animation:tpPop .6s cubic-bezier(.34,1.9,.5,1) forwards,tpSpin 1.25s cubic-bezier(.55,.05,1,.55) forwards}
  .themepop .sym:nth-child(1){animation-delay:.45s,1.5s}.themepop .sym:nth-child(2){animation-delay:.55s,1.55s}.themepop .sym:nth-child(3){animation-delay:.65s,1.6s}.themepop .sym:nth-child(4){animation-delay:.75s,1.65s}
  @keyframes tpPop{to{opacity:1;transform:scale(1) rotate(0)}}
  @keyframes tpSpin{0%{opacity:1;transform:scale(1) rotate(0)}80%{opacity:1}100%{opacity:0;transform:scale(2.6) rotate(360deg)}}
  .themepop .tp-cap{color:#fff;font-weight:800;letter-spacing:.34em;font-size:clamp(11px,2vw,15px);opacity:0;text-align:center}
  .themepop.tp-light .tp-cap{color:#201e1d}
  .themepop.tp-go .tp-cap{animation:tpFade .4s .85s ease forwards,tpCapOut .4s 2.2s ease forwards}
  @keyframes tpFade{to{opacity:.85}}
  @keyframes tpCapOut{to{opacity:0}}
  /* blue-theme entrance only: once the screen is fully blue, every product scrolls past
     above (right to left) and below (left to right) while the symbols pop, then they spin out */
  .themepop.tp-long.tp-go{animation:tpWipe .7s cubic-bezier(.7,0,.2,1) forwards,tpOut .55s 5.6s ease forwards}
  .themepop.tp-long .sym:nth-child(1){animation-delay:.9s,4.7s}.themepop.tp-long .sym:nth-child(2){animation-delay:1s,4.75s}.themepop.tp-long .sym:nth-child(3){animation-delay:1.1s,4.8s}.themepop.tp-long .sym:nth-child(4){animation-delay:1.2s,4.85s}
  .themepop.tp-long.tp-go .tp-cap{animation:tpFade .4s 1.25s ease forwards,tpGrow 1.6s 4.1s cubic-bezier(.4,0,.3,1) forwards,tpCapOut .45s 5.4s ease forwards}
  @keyframes tpGrow{from{transform:scale(1)}to{transform:scale(1.28)}}
  .themepop .prow{position:absolute;left:0;width:max-content;display:flex;gap:clamp(10px,1.6vw,20px);will-change:transform}
  .themepop .prow.top{top:clamp(12px,4vh,40px)}
  .themepop .prow.bot{bottom:clamp(12px,4vh,40px)}
  .themepop .prow img{height:clamp(160px,35vh,560px);width:auto;aspect-ratio:900/1273;border-radius:10px;border:2px solid rgba(255,255,255,0.9);background:#fff;box-shadow:0 12px 28px rgba(6,16,60,0.45);display:block}
  .themepop.tp-go .prow.top{animation:tpRowL 3.6s .7s linear both}
  .themepop.tp-go .prow.bot{animation:tpRowR 3.6s .7s linear both}
  @keyframes tpRowL{from{transform:translateX(100vw)}to{transform:translateX(-100%)}}
  @keyframes tpRowR{from{transform:translateX(-100%)}to{transform:translateX(100vw)}}
  @media(max-height:560px){.themepop .prow{display:none}}
  @media(prefers-reduced-motion:reduce){.themepop{display:none}}
  /* ---- layout of the Press me button in each page's header ---- */
  .bar-left{display:flex;align-items:center;gap:8px;justify-self:start}
  header .bar.has-theme{display:grid;grid-template-columns:1fr auto 1fr;align-items:center;gap:12px}
  header .bar.has-theme nav{justify-self:end}
  header .bar.has-theme .logo{justify-self:center}
  /* ---- themed news + product pages ---- */
  html.ps2 .hero .kicker{color:#ffd3b8}
  html.ps2 .hero h1,html.ps2 .hero .sub{color:#fff}
  html.ps2 .hero .sub{opacity:.88}
  html.ps2 .postcard{background:rgba(255,255,255,0.96);border:1px solid rgba(255,255,255,0.85);box-shadow:0 16px 40px rgba(6,16,60,0.42),inset 0 1px 0 #fff}
  html.ps2 .postcard:hover{box-shadow:0 22px 50px rgba(6,16,60,0.55),0 0 0 2px rgba(255,255,255,0.7)}
  html.ps2 .empty{color:#fff}
  html.ps2 article{background:rgba(255,255,255,0.96);border-radius:22px;padding:30px 32px;box-shadow:0 16px 40px rgba(6,16,60,0.42)}
  html.ps2 header nav a{color:var(--ink)}
  html.ps2 .pdp .info,html.ps2 .pdp .details,html.ps2 .pdp > div:last-child{background:rgba(255,255,255,0.96);border-radius:22px;padding:26px 28px;box-shadow:0 16px 40px rgba(6,16,60,0.42)}
  html.ps2 .loading{color:#fff}
  html.ps2 .media .cap,html.ps2 .vw-hint{color:#e6efff}

  /* small round music button, top-left */
  .themebtn{position:fixed;top:14px;left:14px;z-index:220;width:36px;height:36px;padding:0;gap:0;justify-content:center;font-size:15px;box-shadow:0 4px 14px rgba(0,0,0,0.12)}
  /* keep header content clear of the fixed music + Collection buttons in the top-left corner */
  header .bar-left{padding-left:max(0px, calc(226px - (100vw - 1120px) / 2 - 20px))}
  .themebtn.playing{box-shadow:0 0 0 2px rgba(242,107,58,0.85),0 0 16px rgba(242,107,58,0.6);animation:tbBeat 1.4s ease-in-out infinite}
  @keyframes tbBeat{0%,100%{transform:scale(1)}50%{transform:scale(1.12)}}
  @media(prefers-reduced-motion:reduce){.themebtn.playing{animation:none}}

  /* ---- Entrance (blue theme only): the page is hidden until the script has marked every
     piece, then the pieces assemble strictly top to bottom, one at a time. ---- */
  html.csw-enter:not(.csw-armed) header,html.csw-enter:not(.csw-armed) main,html.csw-enter:not(.csw-armed) footer,html.csw-enter:not(.csw-armed) .salebar{visibility:hidden}
  .ent-wait{opacity:0!important}
  .ent-left{animation:entLeft .55s cubic-bezier(.2,.9,.3,1) both}
  .ent-drop{animation:entDrop .55s cubic-bezier(.2,.9,.3,1) both}
  .ent-slot{animation:entSlot .7s cubic-bezier(.2,.95,.3,1.12) both;transform-origin:50% 100%}
  .ent-flip{animation:entFlip 1.05s cubic-bezier(.16,1,.3,1) both;backface-visibility:hidden}
  @keyframes entLeft{from{opacity:0;transform:translateX(-30px)}to{opacity:1;transform:none}}
  @keyframes entDrop{from{opacity:0;transform:translateY(-100%)}to{opacity:1;transform:none}}
  @keyframes entSlot{0%{opacity:0;transform:perspective(900px) translateY(26px) rotateX(-38deg) rotate(var(--tilt,0deg)) scale(.94)}40%{opacity:1}100%{opacity:1;transform:perspective(900px) translateY(0) rotateX(0) rotate(0) scale(1)}}
  @keyframes entFlip{0%{opacity:0;transform:perspective(1400px) rotateY(var(--spin,-180deg)) scale(.92)}30%{opacity:1}100%{opacity:1;transform:perspective(1400px) rotateY(0) scale(1)}}
  @media(prefers-reduced-motion:reduce){.ent-wait{opacity:1!important}.ent-left,.ent-drop,.ent-slot,.ent-flip{animation:none}}
  html.ps2 .hero::after{transition:opacity .6s}
  .hero:has(> .ent-wait)::after{opacity:0}
  html.ps2 footer a{color:#fff!important;text-decoration:underline;text-underline-offset:2px}
  html.ps2 #grid > .lvlhint{color:#fff;text-shadow:0 2px 12px rgba(8,20,70,0.4)}
  /* load intro: already fully blue, so no wipe; the dark load reveal turns blue underneath it */
  .themepop.tp-preload{clip-path:none}
  .themepop.tp-long.tp-preload.tp-go{animation:tpOut .55s 5.6s ease forwards}
  html.ps2 .loadReveal{background:#2c55b4}
  .themepop .tp-cap{line-height:2.1}
  .themepop .tp-cap .by{display:inline-block;margin-top:2px}
  .soundhint{position:fixed;top:16px;left:58px;z-index:9998;border:none;cursor:pointer;font-family:inherit;font-weight:800;font-size:12.5px;padding:8px 13px;border-radius:999px;background:#fff;color:#0f1c47;box-shadow:0 6px 18px rgba(6,16,60,0.35);animation:shPulse 1.6s ease-in-out infinite}
  @keyframes shPulse{0%,100%{transform:scale(1)}50%{transform:scale(1.06)}}
  .soundhint{z-index:10001}
  /* ---- phones ---- */
  @media(max-width:640px){
    header .bar-left{padding-left:40px}
    .themebtn{top:12px;left:10px}
    .soundhint{top:58px;left:10px}
    .themepop .tp-cap{letter-spacing:.2em;font-size:12px;line-height:1.9;padding:0 14px}
    .themepop .tp-cap .jp,.themepop .tp-cap .en{display:block}
    .themepop .tp-cap .tp-dot{display:none}
    .themepop .tp-cap br{display:none}
    .themepop .tp-cap .by{display:block;margin-top:4px}
    .themepop .syms{gap:18px}
    .themepop .prow img{height:clamp(130px,27vh,260px)}
    #themeBg span{font-size:70%!important}
  }
  body{overflow-x:clip}
  @media(max-width:640px){
    header .bar-left{padding-left:0}
    header .bar{padding-left:100px}
    .soundhint{top:auto;bottom:18px;left:50%;transform:translateX(-50%);animation:none;font-size:13.5px;padding:10px 16px}
    header .bar.has-theme{grid-template-columns:auto 1fr auto}
    header .bar.has-theme .logo{justify-self:start}
    header .bar.has-theme .logo-word{display:none}
    header nav{display:flex;gap:14px}
    header nav a{margin-left:0!important;font-size:13px}
    footer{padding-left:20px!important;padding-right:20px!important}
  }
  /* School licence button: mint green so it stands out from the blue background and the orange CTA */
  html.ps2 .slbtn{background:linear-gradient(120deg,#3fd3a0,#1f9e74);box-shadow:0 16px 40px rgba(6,16,60,0.45),inset 0 1px 0 rgba(255,255,255,0.45);border:1px solid rgba(255,255,255,0.6)}
  html.ps2 .slbtn:hover{box-shadow:0 20px 48px rgba(6,16,60,0.55),0 0 0 3px rgba(255,255,255,0.5)}
  html.ps2 .slbtn-go{color:#1f9e74}

  /* ---- The Collection: a bookshelf of every spine ---- */
  .collbtn{position:fixed;top:14px;left:58px;z-index:220;height:36px;display:inline-flex;align-items:center;gap:7px;padding:0 15px;border-radius:999px;border:1px solid var(--line);background:#fff;color:var(--ink);font-family:inherit;font-weight:800;font-size:13px;cursor:pointer;box-shadow:0 4px 14px rgba(0,0,0,0.12);transition:transform .15s,box-shadow .15s}
  .collbtn:hover{transform:translateY(-1px) scale(1.04);box-shadow:0 6px 18px rgba(0,0,0,0.18)}
  .collbtn .ci{font-size:16px;line-height:1}
  @media(max-width:640px){.collbtn{left:52px;top:12px;width:36px;padding:0;justify-content:center}.collbtn .ct{display:none}}
  .coll{position:fixed;inset:0;z-index:900;display:none}
  .coll.open{display:block}
  .coll-bg{position:absolute;inset:0;background:rgba(12,10,9,0);backdrop-filter:blur(0);-webkit-backdrop-filter:blur(0);transition:background .4s,backdrop-filter .4s}
  .coll.show .coll-bg{background:rgba(12,10,9,0.55);backdrop-filter:blur(5px);-webkit-backdrop-filter:blur(5px)}
  .coll-win{position:absolute;left:50%;top:0;width:min(1180px,100vw);max-height:100vh;overflow:auto;transform:translate(-50%,-105%);transition:transform .75s cubic-bezier(.22,1.25,.36,1);background:linear-gradient(180deg,#fbf7f1,#f1e8db);color:#3a2f27;border-radius:0 0 26px 26px;box-shadow:0 30px 80px rgba(0,0,0,0.55);padding:22px clamp(14px,3vw,34px) 30px}
  .coll.show .coll-win{transform:translate(-50%,0)}
  .coll.closing .coll-win{transition:transform .45s cubic-bezier(.6,0,.8,.2);transform:translate(-50%,-105%)}
  .coll.closing .coll-bg{background:rgba(12,10,9,0);backdrop-filter:blur(0)}
  .coll-head{position:relative;text-align:center;padding:0 48px;margin-bottom:8px}
  .coll-head .coll-x{position:absolute;top:0;right:0}
  .shelf-label{display:flex!important;justify-content:center}
  .coll-head h2{font-size:clamp(26px,3.8vw,40px);font-weight:900;letter-spacing:-.02em;margin:0;color:#2b211b}
  .coll-head p{margin:6px 0 0;color:#8a7764;font-size:14.5px}
  .coll-x{flex:none;width:38px;height:38px;border-radius:50%;border:none;background:rgba(58,47,39,0.08);color:#3a2f27;font-size:22px;line-height:1;cursor:pointer}
  .coll-x:hover{background:rgba(58,47,39,0.16)}
  .shelf{position:relative;margin-top:24px}
  .shelf-label{display:inline-flex;align-items:center;gap:8px;font-size:12px;font-weight:800;letter-spacing:.12em;text-transform:uppercase;color:#a5774a;margin:0 0 8px 0}
  .shelf-label b{font-size:16px;letter-spacing:0;text-transform:none;color:#2b211b}
  .shelf-back{position:relative;border-radius:10px 10px 0 0;background:linear-gradient(180deg,#e9dcc9,#dccbb2 75%,#d3c0a4);box-shadow:inset 0 12px 22px rgba(90,60,30,0.18),inset 0 -2px 0 rgba(90,60,30,0.15);padding:10px 14px 0;overflow-x:auto;overflow-y:hidden;scrollbar-width:thin}
  .shelf-books{display:flex;align-items:flex-end;gap:2px;margin-bottom:-5px;padding-left:60px;padding-right:110px;width:max-content;min-width:100%;justify-content:center;padding-top:66px}
  .shelf-plank{height:20px;border-radius:0 0 8px 8px;background:linear-gradient(180deg,#c9965f,#b07d47 45%,#93633a);box-shadow:0 10px 18px rgba(90,60,30,0.28),inset 0 2px 0 rgba(255,230,190,0.5)}
  /* each book is a little 3D box: the spine faces you, the front cover is the hidden side face.
     Hovering pulls the book out, turns it so the cover shows, and lays a soft shadow under it. */
  .shelf-books{position:relative;cursor:pointer}
  .spine{position:relative;display:block;flex:none;height:var(--sh,260px);outline:none;perspective:1100px;perspective-origin:50% 40%;pointer-events:none;
    transition:transform .5s cubic-bezier(.22,.9,.3,1.05)}
  .spine .bk{position:relative;display:block;height:100%;transform-style:preserve-3d;transform-origin:50% 100% calc(var(--bw) * -0.5);
    transition:transform .5s cubic-bezier(.2,.85,.25,1.08)}
  .spine .sp{position:relative;height:100%;width:auto;display:block;border-radius:2px;backface-visibility:hidden;pointer-events:none;user-select:none;
    box-shadow:inset 0 0 0 1px rgba(0,0,0,0.06)}
  .spine .bk::after{content:"";position:absolute;inset:0;border-radius:2px;pointer-events:none;
    background:linear-gradient(90deg,rgba(255,255,255,0.16),rgba(255,255,255,0) 28%,rgba(0,0,0,0) 72%,rgba(0,0,0,0.2))}
  .spine .cv{position:absolute;top:0;left:100%;height:100%;width:auto;transform-origin:0 50%;transform:rotateY(90deg);backface-visibility:hidden;pointer-events:none;
    border-radius:0 3px 3px 0;filter:brightness(.92)}
  .spine .gs{position:absolute;left:-30%;right:-120%;bottom:-10px;height:22px;border-radius:50%;background:radial-gradient(ellipse at 40% 50%,rgba(40,25,10,0.38),rgba(40,25,10,0) 70%);
    opacity:0;transform:scaleX(.6);transition:opacity .45s,transform .45s;pointer-events:none;filter:blur(3px)}
  .shelf-books.has-hov .spine:not(.hov) .sp{filter:brightness(.88) saturate(.92)}
  .sp{transition:filter .3s}
  .spine.hov{z-index:4}
  .spine.hov .bk{transform:translateY(-12px) translateZ(36px) rotateY(-38deg) scale(1.1)}
  .spine.hov .gs{opacity:1;transform:scaleX(1)}
  /* books either side slide apart (transform only, so nothing reflows and the hover never jumps) */
  .spine.lf{transform:translateX(calc(var(--sh,260px) * -0.10))}
  .spine.rt{transform:translateX(calc(var(--sh,260px) * 0.52))}
  .spine.lf.adj{transform:translateX(calc(var(--sh,260px) * -0.10)) translateY(3px)}
  .spine.rt.adj{transform:translateX(calc(var(--sh,260px) * 0.52)) translateY(3px)}
  .spine.away .bk,.spine.away .gs{opacity:0;transition:none}
  .spine.lifting .bk{transform:translateY(-14px) translateZ(36px) rotateY(-38deg) scale(1.1);animation:bkWait 1s ease-in-out infinite}
  @keyframes bkWait{50%{filter:brightness(1.08)}}
  .spine.returning .bk{animation:bkReturn .55s cubic-bezier(.2,.9,.3,1.15)}
  @keyframes bkReturn{from{opacity:.2;transform:translateY(-26px) scale(1.06)}to{opacity:1;transform:none}}
  .coll.show .spine{animation:spineIn 1s cubic-bezier(.2,.9,.3,1.15) backwards;animation-delay:calc(.6s + var(--i) * 85ms)}
  @keyframes spineIn{from{opacity:0;transform:translateY(-60px)}to{opacity:1;transform:none}}
  .coll-tip{position:fixed;z-index:950;pointer-events:none;transform:translate(-50%,calc(-100% - 12px)) scale(.92);opacity:0;transition:opacity .15s,transform .18s;background:#2b211b;color:#fff;border-radius:12px;padding:9px 13px;box-shadow:0 12px 30px rgba(0,0,0,0.4);max-width:240px;text-align:center}
  .coll-tip.on{opacity:1;transform:translate(-50%,calc(-100% - 12px)) scale(1)}
  .coll-tip::after{content:"";position:absolute;left:50%;bottom:-7px;margin-left:-7px;border:7px solid transparent;border-bottom:0;border-top-color:#2b211b}
  .coll-tip b{display:block;font-size:13.5px;line-height:1.3}
  .coll-tip span{display:block;font-size:12px;color:#f3d9a8;margin-top:3px;font-weight:700}
  .coll-hint{margin-top:16px;text-align:center;font-size:13px;color:#8a7764}
  @media(max-width:640px){.coll-win{border-radius:0;height:100vh}.shelf-books{justify-content:flex-start}}
  @media(prefers-reduced-motion:reduce){.coll-win,.coll.closing .coll-win{transition:none}.coll.show .spine{animation:none}}

  /* ---- 3D book viewer (opens when a book is picked) ---- */
  .bv{position:fixed;inset:0;z-index:960;display:none;align-items:center;justify-content:center;pointer-events:none}
  .bv.vis{display:flex}
  .bv-bg{position:absolute;inset:0;background:rgba(40,30,22,0);transition:background .45s;pointer-events:auto}
  .bv-bg{transition:background .6s,backdrop-filter .6s}
  .bv.show .bv-bg{background:rgba(30,22,16,0.62);backdrop-filter:blur(3px);-webkit-backdrop-filter:blur(3px)}
  .bv-card{position:absolute;inset:0;pointer-events:none}
  .bv canvas{position:absolute;inset:0;width:100%!important;height:100%!important;display:block;pointer-events:auto;cursor:grab}
  .bv canvas:active{cursor:grabbing}
  .bv-side{position:absolute;right:max(20px,calc(50vw - 520px));top:50%;transform:translateY(-50%);width:min(330px,32vw);display:flex;flex-direction:column;gap:10px;align-items:stretch;
    pointer-events:auto;opacity:0;transition:opacity .35s}
  .bv.ready .bv-side{opacity:1}
  .bv-side h3{margin:0;font-size:clamp(18px,2.2vw,24px);font-weight:900;color:#fff;letter-spacing:-.01em;line-height:1.2;text-shadow:0 2px 14px rgba(0,0,0,0.35)}
  .bv-side p{margin:0 0 8px;font-size:14px;font-weight:800;color:#f3d9a8}
  .bv-x{position:absolute;top:20px;right:max(20px,calc(50vw - 520px));z-index:2;width:42px;height:42px;border:none;border-radius:50%;background:rgba(255,255,255,0.18);color:#fff;font-size:24px;line-height:1;cursor:pointer;pointer-events:auto;opacity:0;transition:opacity .3s}
  .bv.ready .bv-x{opacity:1}
  .bv-x:hover{background:rgba(255,255,255,0.3)}
  .bv-side button{font-family:inherit;font-weight:800;font-size:15px;border-radius:14px;padding:13px 18px;cursor:pointer;border:none;background:#fff;color:#2b211b;text-align:left;
    box-shadow:0 8px 20px rgba(0,0,0,0.25);opacity:0;transform:translateX(16px);transition:opacity .3s,transform .3s,box-shadow .15s}
  .bv.ready .bv-side button{opacity:1;transform:none}
  .bv.ready .bv-side button:nth-of-type(2){transition-delay:.07s}.bv.ready .bv-side button:nth-of-type(3){transition-delay:.14s}
  .bv-side button:hover{box-shadow:0 12px 26px rgba(0,0,0,0.32)}
  .bv-side .bv-open{background:var(--red,#ec3013);color:#fff}
  html.ps2 .bv-side .bv-open{background:#f26b3a}
  .bv-side button span{display:block;font-size:12px;font-weight:700;opacity:.65;margin-top:2px}
  @media(max-width:700px){
    .bv-side{top:auto;bottom:16px;right:16px;left:16px;transform:none;width:auto;flex-direction:row;flex-wrap:wrap;justify-content:center}
    .bv-side h3,.bv-side p{width:100%;text-align:center}
    .bv-side button{flex:1;text-align:center;padding:12px 10px;font-size:14px}
    .bv-side button span{display:none}
  }
  /* ---- bubble page transition (circle grows from where you clicked) ---- */
  .bubnav{position:fixed;inset:0;z-index:99999;pointer-events:none;background:#201e1d;clip-path:circle(0 at var(--x) var(--y));animation:bubIn .55s cubic-bezier(.65,0,.35,1) forwards}
  html.ps2 .bubnav{background:#2c55b4}
  @keyframes bubIn{to{clip-path:circle(150% at var(--x) var(--y))}}

  /* ---- intro can be skipped with a click or key ---- */
  .themepop.tp-long.tp-preload{pointer-events:auto;cursor:pointer}
  .themepop.tp-skip{animation:tpSkip .35s ease forwards!important}
  .themepop.tp-skip *{animation-play-state:paused!important}
  @keyframes tpSkip{to{opacity:0}}
  .themepop .skiphint{position:absolute;left:50%;bottom:clamp(12px,3vh,26px);transform:translateX(-50%);color:rgba(255,255,255,0.75);font-size:12px;font-weight:800;letter-spacing:.14em;text-transform:uppercase;opacity:0;animation:tpFade .4s 1.2s ease forwards;z-index:2;white-space:nowrap}
  @media(max-height:560px){.themepop .skiphint{display:none}}

  /* ---- The Collection on phones ---- */
  .shelf-books{touch-action:pan-y;-webkit-user-select:none;user-select:none;-webkit-touch-callout:none}
  .bv canvas{touch-action:none}
  @media(max-width:699px){
    .coll-win{padding:16px 12px 24px}
    .coll-head{padding:0 44px}
    .coll-head h2{font-size:26px}
    .coll-head p{font-size:13px}
    .shelf{margin-top:14px}
    .shelf-label{font-size:11px;margin-bottom:6px}
    .shelf-label b{font-size:14px}
    .shelf-back{overflow:hidden;padding:6px 8px 0;border-radius:8px 8px 0 0}
    .shelf-books{justify-content:center!important;padding-top:46px;padding-left:12px;padding-right:12px}
    .spine.rt{transform:translateX(calc(var(--sh,260px) * 0.20))}
    .spine.lf{transform:translateX(calc(var(--sh,260px) * -0.06))}
    .spine.rt.adj{transform:translateX(calc(var(--sh,260px) * 0.20)) translateY(3px)}
    .spine.lf.adj{transform:translateX(calc(var(--sh,260px) * -0.06)) translateY(3px)}
    .spine.hov .bk{transform:translateY(-10px) translateZ(26px) rotateY(-30deg) scale(1.12)}
    .shelf-plank{height:14px}
    .coll-hint{font-size:12.5px;padding:0 10px}
    .coll-tip{max-width:200px;padding:7px 11px}
    .coll-tip b{font-size:12.5px}
  }
  /* ---- Vault Plus pages on the blue theme: light text on the blue, white cards for reading ---- */
  html.ps2 .vp-kicker{color:#cfe2ff}
  html.ps2 .vp-hero h1,html.ps2 .vp-h2,html.ps2 .vp-stats b,html.ps2 .vp-now{color:#fff;text-shadow:0 2px 14px rgba(8,20,70,0.35)}
  html.ps2 .vp-now small,html.ps2 .vp-sub,html.ps2 .vp-stats span,html.ps2 .vp-was,html.ps2 .vp-school-note{color:rgba(255,255,255,0.86)}
  html.ps2 .vp-long,html.ps2 .vp .lic{background:rgba(255,255,255,0.96);color:#201e1d;border-radius:22px;padding:24px 28px;box-shadow:0 16px 40px rgba(6,16,60,0.42);border:none}
  html.ps2 .vp-long li{color:#201e1d}
  html.ps2 .vp-marquee{background:linear-gradient(120deg,#1f3f8f,#162f6e)}
  @media(max-width:560px){html.ps2 .vp-long,html.ps2 .vp .lic{padding:18px}}
  html.ps2 #articleView .back{color:#fff;text-shadow:0 1px 8px rgba(8,20,70,0.35)}
  html.ps2 #articleView .back:hover{color:#ffd3b8}
  /* ---- header buttons: part of the header (not floating), same pill style as News / Menu, aligned with the logo ---- */
  .themebtn,.collbtn,header .back{position:static;box-sizing:border-box;height:38px;display:inline-flex;align-items:center;justify-content:center;gap:8px;margin:0;border:1px solid var(--line);background:#fff;color:var(--ink);font-family:inherit;font-weight:700;font-size:13px;line-height:1;border-radius:999px;text-decoration:none;white-space:nowrap;box-shadow:none;cursor:pointer;transition:transform .15s,box-shadow .15s}
  .themebtn{width:38px;padding:0}
  .collbtn{padding:0 14px}
  header .back{padding:0 14px}
  .themebtn:hover,.collbtn:hover,header .back:hover{transform:translateY(-1px);box-shadow:0 4px 14px rgba(0,0,0,0.14)}
  .themebtn .tb-ic,.collbtn .ci{font-size:16px;line-height:1}
  header .bar-left{display:flex;align-items:center;gap:8px;padding-left:0;min-width:0}
  header .bar{padding-left:0}
  html.ps2 .themebtn.playing{border-color:#f26b3a}
  /* when the header gets tight the buttons shrink to icons first, so nothing ever touches the logo */
  @media(max-width:1100px){ .collbtn{width:38px;padding:0} .collbtn .ct{display:none} header .back{width:38px;padding:0} header .back span{display:none} }
  @media(max-width:640px){ .collbtn,.themebtn,header .back{height:36px} .themebtn,.collbtn,header .back{width:36px} header .bar-left{gap:6px} .soundhint{top:auto} }
  @media(max-width:640px){ header .logo-word{display:none} header .bar{gap:8px} }
  header nav{white-space:nowrap}
  @media(max-width:760px){header nav a{margin-left:12px!important;font-size:13px}}

  /* ================= My Collection ================= */
  /* the button: top right, same pill as the other header buttons */
  .mycollbtn{box-sizing:border-box;height:38px;display:inline-flex;align-items:center;justify-content:center;gap:8px;margin:0;padding:0 14px;border:1px solid var(--line);background:#fff;color:var(--ink);font-family:inherit;font-weight:700;font-size:13px;line-height:1;border-radius:999px;white-space:nowrap;cursor:pointer;transition:transform .15s,box-shadow .15s}
  .mycollbtn:hover{transform:translateY(-1px);box-shadow:0 4px 14px rgba(0,0,0,0.14)}
  .mycollbtn .ci{font-size:16px;line-height:1}
  header .bar.has-theme .hdr-right{justify-self:end;display:flex;align-items:center;gap:10px}
  header .bar.has-theme .hdr-right nav{display:flex;align-items:center}
  @media(max-width:1100px){ .mycollbtn{width:38px;padding:0} .mycollbtn .ct{display:none} }
  @media(max-width:640px){ .mycollbtn{width:36px;height:36px} header .bar.has-theme .hdr-right{gap:6px} }
  /* news page on small phones: keep the header to one tidy row */
  @media(max-width:520px){ header .bar.has-theme .hdr-right nav a[href$="/cs-world/news"],header .bar.has-theme .hdr-right nav a[href$="#contact"]{display:none} }


  /* a gutter either side of the header, so the corner buttons never touch the screen edge */
  header .bar{box-sizing:border-box;padding-left:clamp(10px,2vw,20px);padding-right:clamp(10px,2vw,20px)}


/* ======================= Punchy tactile header =======================
   Thick ink outlines, flat offset shadows, bright fills. Restyles the existing header on every page (shop, product, news)
   without touching its markup or behaviour. */
header{--hk-ink:#111;--hk-yellow:#FFD60A;--hk-coral:#FF5A36;--hk-blue:#2F5BFF;--hk-font:'Bricolage Grotesque',system-ui,-apple-system,'Segoe UI',sans-serif;
  background:#F3F2F1!important;backdrop-filter:none!important;-webkit-backdrop-filter:none!important;border-bottom:3px solid var(--hk-ink)!important;font-family:var(--hk-font)}
html.ps2 header{background:#F3F2F1!important}
header .bar{display:flex!important;flex-wrap:wrap;align-items:center;justify-content:space-between;gap:12px 16px;padding-top:14px!important;padding-bottom:14px!important;max-width:1360px;margin:0 auto}
header .bar-left,header .hdr-right{display:flex;align-items:center;flex-wrap:wrap;gap:14px;padding-left:0!important;min-width:0}
header .hdr-right{justify-content:flex-end}
header .hdr-right nav{display:flex;align-items:center;gap:14px}

/* the buttons */
header .themebtn,header .collbtn,header .back,header .navbtn,header .cartbtn,header .mycollbtn,header nav a{
  position:relative;box-sizing:border-box;display:inline-flex;align-items:center;justify-content:center;gap:9px;height:46px;min-width:46px;padding:0 20px;margin:0!important;
  border:3px solid var(--hk-ink);border-radius:14px;background:#fff;color:var(--hk-ink);font:800 16px/1 var(--hk-font);letter-spacing:-.01em;text-decoration:none;white-space:nowrap;cursor:pointer;
  box-shadow:4px 4px 0 var(--hk-ink);transition:transform .12s ease,box-shadow .12s ease;-webkit-tap-highlight-color:transparent}
header .themebtn:hover,header .collbtn:hover,header .back:hover,header .navbtn:hover,header .cartbtn:hover,header .mycollbtn:hover,header nav a:hover{transform:translate(-2px,-2px);box-shadow:6px 6px 0 var(--hk-ink);color:var(--hk-ink)}
header .themebtn:active,header .collbtn:active,header .back:active,header .navbtn:active,header .cartbtn:active,header .mycollbtn:active,header nav a:active{transform:translate(4px,4px);box-shadow:0 0 0 var(--hk-ink)}
header .themebtn:focus-visible,header .collbtn:focus-visible,header .back:focus-visible,header .navbtn:focus-visible,header .cartbtn:focus-visible,header .mycollbtn:focus-visible,header nav a:focus-visible{outline:3px solid var(--hk-blue);outline-offset:4px}
header .themebtn{background:var(--hk-yellow);width:50px;padding:0}
header .navbtn.newsbtn,header nav a[href$="/cs-world/news"]{background:var(--hk-yellow);color:var(--hk-ink)}
header .cartbtn{background:var(--hk-coral);color:var(--hk-ink)}
header .mycollbtn{background:var(--hk-blue);color:#fff}
header .mycollbtn:hover{color:#fff}
header .cartbtn .count{min-width:26px;height:26px;padding:0 7px;border-radius:999px;background:var(--hk-ink);color:#fff;font:800 14px/1 var(--hk-font);display:inline-flex;align-items:center;justify-content:center}
/* emoji out; the buttons are all words (their text is always shown) */
header .navbtn.newsbtn,header .cartbtn{font-size:0}
header .navbtn.newsbtn .navbtn-txt,header .cartbtn .cartbtn-txt{display:inline!important;font-size:16px}
header .navbtn .navbtn-txt{display:inline!important}
header .collbtn .ci,header .mycollbtn .ci{display:none}
header .collbtn .ct,header .mycollbtn .ct{display:inline!important}
header .collbtn,header .mycollbtn{width:auto!important;padding:0 20px!important}
/* Menu glyph: two bars */
header .navbtn-lines{display:inline-flex;flex-direction:column;gap:5px;align-items:flex-start;width:auto}
header .navbtn-lines i{display:block;height:3px;border-radius:2px;background:var(--hk-ink)}
header .navbtn-lines i:nth-child(1){width:22px} header .navbtn-lines i:nth-child(2){width:14px;transition:width .15s ease} header .navbtn-lines i:nth-child(3){display:none}
header .navbtn:hover .navbtn-lines i:nth-child(2){width:22px}
/* the music button: animated sound bars, still when the music is off */
header .themebtn .tb-ic{font-size:0;display:block;width:29px;height:20px;
  background:linear-gradient(var(--hk-ink),var(--hk-ink)) 0 100%/5px 8px no-repeat,linear-gradient(var(--hk-ink),var(--hk-ink)) 8px 100%/5px 12px no-repeat,linear-gradient(var(--hk-ink),var(--hk-ink)) 16px 100%/5px 9px no-repeat,linear-gradient(var(--hk-ink),var(--hk-ink)) 24px 100%/5px 13px no-repeat;border-radius:2px}
header .themebtn.playing .tb-ic{animation:hkeq .9s ease-in-out infinite}
@keyframes hkeq{0%,100%{background-size:5px 8px,5px 20px,5px 9px,5px 13px}25%{background-size:5px 18px,5px 10px,5px 20px,5px 8px}50%{background-size:5px 11px,5px 17px,5px 7px,5px 20px}75%{background-size:5px 20px,5px 8px,5px 15px,5px 11px}}
html.ps2 .themebtn.playing{border-color:var(--hk-ink)}
/* the menu that drops down */
header .navmenu{border:3px solid var(--hk-ink)!important;border-radius:16px!important;box-shadow:6px 6px 0 var(--hk-ink)!important;background:#fff!important;font-family:var(--hk-font)}
header .navmenu a{font:700 15px/1.2 var(--hk-font)!important;border-radius:10px!important}
header .navmenu a:hover{background:var(--hk-yellow)!important}
/* the brand */
header .logo{display:flex!important;align-items:center;gap:16px;color:var(--hk-ink);text-decoration:none;justify-self:auto!important;margin:0 auto 0 4px}
header .logo-mark{width:58px!important;height:58px!important;flex:none;display:flex;align-items:center;justify-content:center;border:3px solid var(--hk-ink)!important;border-radius:16px!important;background:var(--hk-yellow)!important;color:var(--hk-ink)!important;box-shadow:4px 4px 0 var(--hk-ink);font:700 21px/1 'JetBrains Mono','Courier New',ui-monospace,monospace!important;padding:0!important}
header .logo-word{display:flex!important;flex-direction:column;align-items:flex-start;font:800 clamp(20px,2.4vw,32px)/1 var(--hk-font)!important;letter-spacing:-.025em;color:var(--hk-ink)}
header .logo-word small{display:inline-block!important;margin-top:7px;padding:4px 10px;border-radius:6px;background:var(--hk-ink);color:var(--hk-yellow)!important;font:800 12px/1.2 var(--hk-font);letter-spacing:.14em;text-transform:uppercase}

/* laptops and tablets: everything stays on ONE row, left to right; things shrink in steps instead of wrapping and squashing */
@media(min-width:761px){
  header .bar,header .bar-left,header .hdr-right,header .hdr-right nav{flex-wrap:nowrap!important}
  header .hdr-right{flex:none} header .bar-left{flex:1 1 auto;min-width:0} header .logo{flex:none;min-width:0;margin:0 auto 0 4px} header .bar{max-width:1760px}
  header .logo-word{white-space:nowrap}
}
@media(max-width:1480px) and (min-width:761px){
  header .bar{padding-left:clamp(14px,2vw,28px)!important;padding-right:clamp(14px,2vw,28px)!important;gap:10px}
  header .bar-left,header .hdr-right,header .hdr-right nav{gap:10px}
  header .themebtn,header .collbtn,header .back,header .navbtn,header .cartbtn,header .mycollbtn,header nav a{height:42px;min-width:42px;padding:0 14px;border-width:3px;border-radius:12px;box-shadow:3px 3px 0 var(--hk-ink)}
  header .back,header .collbtn,header .mycollbtn,header nav a{font-size:14px} header .navbtn .navbtn-txt{font-size:14px}
  header .collbtn,header .mycollbtn{padding:0 14px!important}
  header .themebtn{width:44px;padding:0}
  header .navbtn.newsbtn .navbtn-txt,header .cartbtn .cartbtn-txt{font-size:14px}
  html header .myflashbtn{height:42px;min-width:42px;border-radius:12px;padding:0 14px;font-size:14px;border-width:3px;box-shadow:3px 3px 0 #FFD60A,3px 3px 0 3px var(--hk-ink)} html.ps2 header .myflashbtn{box-shadow:3px 3px 0 var(--hk-ink),0 0 18px rgba(255,200,40,.5)}
  header .logo{gap:12px} header .logo-mark{width:50px!important;height:50px!important;border-radius:14px!important;font-size:18px!important}
  header .logo-word{font-size:clamp(18px,1.9vw,26px)!important} header .logo-word small{font-size:10px;margin-top:5px}
}
@media(max-width:1280px) and (min-width:761px){ html header .myflashbtn{width:42px;padding:0} header .myflashbtn .ct{display:none} header .logo-word small{display:none!important} }
@media(max-width:1020px) and (min-width:761px){ header .logo-word{display:none!important} }
/* phones: smaller buttons, and the header no longer sticks (it would take too much of the screen) */
@media(max-width:760px){
  header{position:relative!important}
  header .bar{gap:12px 10px;padding-top:12px!important;padding-bottom:16px!important}
  header .bar-left,header .hdr-right,header .hdr-right nav{gap:10px;flex-wrap:wrap}
  header .themebtn,header .collbtn,header .back,header .navbtn,header .cartbtn,header .mycollbtn,header nav a{height:40px;min-width:40px;padding:0 13px;font-size:14px;border-width:2.5px;border-radius:12px;box-shadow:3px 3px 0 var(--hk-ink)}
  header .collbtn,header .mycollbtn{padding:0 13px!important}
  header .themebtn{width:44px;padding:0}
  header .navbtn.newsbtn .navbtn-txt,header .cartbtn .cartbtn-txt{font-size:14px}
  header .cartbtn .count{min-width:22px;height:22px;font-size:12px}
  header .logo{gap:12px}
  header .logo-mark{width:48px!important;height:48px!important;border-radius:13px!important;font-size:17px!important}
  header .logo-word{font-size:24px!important;display:flex!important}
  header .logo-word small{font-size:11px;margin-top:5px}
  header .back span{display:inline!important}
  header .bar.has-theme .hdr-right nav a[href$="/cs-world/news"],header .bar.has-theme .hdr-right nav a[href$="#contact"]{display:inline-flex!important}
}
@media(prefers-reduced-motion:reduce){ header .themebtn,header .collbtn,header .back,header .navbtn,header .cartbtn,header .mycollbtn,header nav a,header .navbtn-lines i{transition:none} header .themebtn.playing .tb-ic{animation:none} }
/* the old floating-button offsets no longer apply: they sit in the header row */
header .themebtn,header .collbtn,header .mycollbtn,header .back{top:auto!important;left:auto!important;right:auto!important;bottom:auto!important}
header .navbtn.newsbtn,header .cartbtn{gap:0}
header .cartbtn .count{margin-left:9px}
/* product page: its basket link has no text of its own, so give it the word */
header a.cartbtn:not(:has(.cartbtn-txt))::before{content:"Basket";font-size:16px;margin-right:9px}
header .back{width:auto!important;padding:0 18px!important}
header .back span{display:inline!important}
@media(max-width:760px){
  header .navbtn.newsbtn,header .cartbtn{font-size:0}
  header a.cartbtn:not(:has(.cartbtn-txt))::before{font-size:14px;margin-right:8px}
  header .back{padding:0 13px!important}
  header .bar-left,header .hdr-right{width:100%;justify-content:flex-start}
  header .hdr-right nav{width:auto}
}
@media(max-width:1280px){ header .navmenu{right:auto;left:0;min-width:min(250px,calc(100vw - 32px))} }
/* the old coloured line under the header was anchored to the page (not the header) on the news page, which put it across the middle: the header has its own outline now */
html.ps2 header::after{display:none!important}
@media(min-width:761px){ header{position:sticky!important;top:0;z-index:100} }

/* ======== My Flashcards (header): one look for each theme ======== */
.myflashbtn{box-sizing:border-box;height:38px;display:inline-flex;align-items:center;justify-content:center;gap:8px;margin:0;padding:0 14px;border:1px solid var(--line);background:#fff;color:var(--ink);font-family:inherit;font-weight:700;font-size:13px;line-height:1;border-radius:999px;white-space:nowrap;cursor:pointer;text-decoration:none;transition:transform .15s,box-shadow .15s}
.myflashbtn:hover{transform:translateY(-1px);box-shadow:0 4px 14px rgba(0,0,0,0.14)}
@media(max-width:1100px){ .myflashbtn{width:38px;padding:0} .myflashbtn .ct{display:none} }
@media(max-width:640px){ .myflashbtn{width:36px;height:36px} }
/* the punchy theme: ink with gold, a gold sparkle on the cards */
header .myflashbtn{position:relative;box-sizing:border-box;display:inline-flex;align-items:center;justify-content:center;gap:9px;height:46px;min-width:46px;padding:0 20px;margin:0!important;border:3px solid var(--hk-ink);border-radius:14px;background:var(--hk-ink);color:#FFD60A;font:800 16px/1 var(--hk-font);letter-spacing:-.01em;text-decoration:none;white-space:nowrap;cursor:pointer;box-shadow:4px 4px 0 #FFD60A,4px 4px 0 3px var(--hk-ink);transition:transform .12s ease,box-shadow .12s ease}
header .myflashbtn:hover{transform:translate(-2px,-2px);box-shadow:6px 6px 0 #FFD60A,6px 6px 0 3px var(--hk-ink);color:#FFD60A}
header .myflashbtn:active{transform:translate(4px,4px);box-shadow:0 0 0 var(--hk-ink)}
header .myflashbtn:focus-visible{outline:3px solid var(--hk-blue);outline-offset:4px}
header .myflashbtn .fi{display:block;flex:none;color:#FFD60A} header .myflashbtn .fi rect:first-child{fill:#fffcf6;stroke:#FFD60A}
header .myflashbtn .ct{display:inline}
header .myflashbtn:hover .fi{animation:mfSpark .6s ease}
@keyframes mfSpark{0%{transform:rotate(0)}40%{transform:rotate(-12deg) scale(1.12)}100%{transform:rotate(0)}}
/* the blue theme: gold, lit from within, with a glow */
html.ps2 header .myflashbtn{background:linear-gradient(180deg,#FFE27A,#FFC21A 70%,#F5A800);color:#1a1200;border-color:var(--hk-ink);box-shadow:4px 4px 0 var(--hk-ink),0 0 22px rgba(255,200,40,.55)}
html.ps2 header .myflashbtn:hover{color:#1a1200;box-shadow:6px 6px 0 var(--hk-ink),0 0 30px rgba(255,200,40,.8)}
html.ps2 header .myflashbtn:active{box-shadow:0 0 0 var(--hk-ink)}
html.ps2 header .myflashbtn .fi{color:#1a1200} html.ps2 header .myflashbtn .fi rect:first-child{fill:#fffcf6;stroke:#1a1200}
html.ps2 header .myflashbtn .fi path{fill:#c2410c}
@media(max-width:1100px){ header .myflashbtn{width:46px;padding:0} header .myflashbtn .ct{display:none} }
@media(max-width:760px){ header .myflashbtn{height:40px;min-width:40px;width:40px;padding:0;border-width:2.5px;border-radius:12px;box-shadow:3px 3px 0 #FFD60A,3px 3px 0 2.5px var(--hk-ink)} html.ps2 header .myflashbtn{box-shadow:3px 3px 0 var(--hk-ink),0 0 16px rgba(255,200,40,.5)} }
@media(prefers-reduced-motion:reduce){ header .myflashbtn,header .myflashbtn:hover .fi{transition:none;animation:none} }

/* ---- the Rain button (flashcards page): raindrops, in the same punchy style as the other header buttons ---- */
header .rainbtn{position:relative;box-sizing:border-box;display:inline-flex;align-items:center;justify-content:center;gap:9px;height:46px;min-width:46px;padding:0 18px;margin:0!important;border:3px solid var(--hk-ink);border-radius:14px;background:#9AD7FF;color:var(--hk-ink);font:800 16px/1 var(--hk-font);letter-spacing:-.01em;white-space:nowrap;cursor:pointer;box-shadow:4px 4px 0 var(--hk-ink);transition:transform .12s ease,box-shadow .12s ease,background .2s,color .2s}
header .rainbtn:hover{transform:translate(-2px,-2px);box-shadow:6px 6px 0 var(--hk-ink)}
header .rainbtn:active{transform:translate(4px,4px);box-shadow:0 0 0 var(--hk-ink)}
header .rainbtn:focus-visible{outline:3px solid var(--hk-blue);outline-offset:4px}
header .rainbtn .ri{display:block;flex:none;overflow:visible} header .rainbtn .d{fill:none;stroke:currentColor;stroke-width:2.2;stroke-linecap:round}
header .rainbtn.on{background:var(--hk-ink);color:#9AD7FF}
header .rainbtn.on .d{animation:rainDrop .9s linear infinite} header .rainbtn.on .d2{animation-delay:.3s} header .rainbtn.on .d3{animation-delay:.6s}
@keyframes rainDrop{0%{transform:translateY(-3px);opacity:0}25%{opacity:1}100%{transform:translateY(5px);opacity:0}}
@media(max-width:1280px) and (min-width:761px){ html header .rainbtn{width:42px;height:42px;min-width:42px;padding:0;border-radius:12px;box-shadow:3px 3px 0 var(--hk-ink)} header .rainbtn .ct{display:none} }
@media(max-width:760px){ header .rainbtn{width:40px;height:40px;min-width:40px;padding:0;border-width:2.5px;border-radius:12px;box-shadow:3px 3px 0 var(--hk-ink)} header .rainbtn .ct{display:none} }
@media(prefers-reduced-motion:reduce){ header .rainbtn.on .d{animation:none} }

/* ---- the logo sits in the true middle of the header: left buttons | logo | right buttons (never wrapping, never overlapping) ---- */
@media(min-width:761px){
  html header .bar,html header .bar.has-theme{display:grid!important;grid-template-columns:var(--hc,auto) minmax(0,1fr) var(--hc,auto)!important;align-items:center;column-gap:14px}
  header .bar > .bar-left{justify-self:start;flex:none}
  html header .bar > .logo{justify-self:center!important;margin:0!important}
  header .bar > .hdr-right{justify-self:end}
  header .bar > .cartbtn{justify-self:end}
}
/* the My Flashcards label really does go when the button is only an icon (this must come after the base rule) */
@media(max-width:1280px) and (min-width:761px){ html header .myflashbtn .ct{display:none} }
@media(max-width:1100px) and (min-width:761px){ html header .myflashbtn .ct{display:none} }
@media(max-width:760px){ html header .myflashbtn .ct{display:none} }

/* ===== phones: a compact header. The logo gets its own slim row; every button then sits in one wrapped row, icon-only where the picture says it all ===== */
@media(max-width:760px){
  html header .bar{display:flex!important;flex-wrap:wrap!important;align-items:center;justify-content:flex-start;gap:8px;padding:10px 14px 12px!important}
  html header .bar > .bar-left,html header .bar > .hdr-right,html header .hdr-right nav{display:contents!important}
  html header .bar > .logo{order:-1;flex:1 0 100%;margin:0!important;justify-content:flex-start;gap:10px}
  html header .logo-mark{width:40px!important;height:40px!important;border-radius:11px!important;font-size:15px!important;border-width:2.5px!important;box-shadow:3px 3px 0 var(--hk-ink)}
  html header .logo-word{font-size:20px!important} html header .logo-word small{display:none!important}
  html header .themebtn,html header .back,html header .navbtn,html header .cartbtn,html header .mycollbtn,html header .collbtn,html header nav a,html header .myflashbtn,html header .rainbtn{
    height:38px!important;min-width:38px;padding:0 11px!important;font-size:13.5px!important;border-width:2.5px!important;border-radius:11px!important;box-shadow:3px 3px 0 var(--hk-ink)!important;flex:0 0 auto;margin:0!important}
  html header .themebtn,html header .navbtn,html header .myflashbtn,html header .rainbtn{width:38px;padding:0!important}
  html header .navbtn .navbtn-txt{display:none!important}
  html header .myflashbtn .ct,html header .rainbtn .ct{display:none!important}
  html header .navbtn.newsbtn,html header .cartbtn{font-size:0!important}
  html header .navbtn.newsbtn .navbtn-txt,html header .cartbtn .cartbtn-txt{font-size:13.5px!important}
  html header .navbtn.newsbtn{width:auto;padding:0 11px!important} html header .navbtn.newsbtn .navbtn-txt{display:inline!important}
  html header .cartbtn .count{min-width:22px;height:22px;font-size:12px}
  html header .myflashbtn{box-shadow:3px 3px 0 #FFD60A,3px 3px 0 2.5px var(--hk-ink)!important}
}

/* Sign in: the button, the bubble that asks for the key, and the buttons that only show once someone is signed in */
header .mycollbtn[hidden]{display:none!important}
header .signinbtn,header .signinbtn:hover{background:#fff;color:var(--hk-ink)}
header .signinbtn .ci{display:none}
.mcpop{animation:mcpop .6s cubic-bezier(.2,1.3,.4,1) both}
@keyframes mcpop{from{opacity:0;transform:scale(.55) rotate(-7deg)}55%{opacity:1;transform:scale(1.1) rotate(2deg)}to{opacity:1;transform:none}}
.signinpop{position:fixed;z-index:9500;width:min(350px,calc(100vw - 24px));box-sizing:border-box;padding:20px 20px 16px;background:#fff;color:#111;border:3px solid #111;border-radius:20px;box-shadow:7px 7px 0 #111;font-family:'Bricolage Grotesque',system-ui,-apple-system,'Segoe UI',sans-serif;opacity:0;transform:translateY(-10px) scale(.94);transform-origin:var(--ax,85%) 0;transition:opacity .18s ease,transform .26s cubic-bezier(.2,1.4,.4,1)}
.signinpop.on{opacity:1;transform:none}
.signinpop .sp-arrow{position:absolute;top:-12px;left:var(--ax,85%);width:20px;height:20px;margin-left:-10px;background:#fff;border-left:3px solid #111;border-top:3px solid #111;transform:rotate(45deg);border-top-left-radius:5px}
.signinpop .sp-t{display:block;font:800 26px/1 'Bricolage Grotesque',system-ui,sans-serif;letter-spacing:-.02em}
.signinpop .sp-p{margin:8px 0 14px;font:600 14px/1.4 'Bricolage Grotesque',system-ui,sans-serif;color:#4b4742}
.signinpop .sp-f{display:flex;flex-direction:column;gap:10px}
.signinpop .sp-in{box-sizing:border-box;width:100%;padding:13px 14px;border:3px solid #111;border-radius:12px;background:#fffcf6;color:#111;font:700 15px/1 ui-monospace,Consolas,monospace;letter-spacing:.03em}
.signinpop .sp-in:focus{outline:3px solid #2F5BFF;outline-offset:2px}
.signinpop .sp-go{padding:13px 18px;border:3px solid #111;border-radius:12px;background:#FFD60A;color:#111;font:800 16px/1 'Bricolage Grotesque',system-ui,sans-serif;cursor:pointer;box-shadow:4px 4px 0 #111;transition:transform .12s,box-shadow .12s}
.signinpop .sp-go:hover{transform:translate(-2px,-2px);box-shadow:6px 6px 0 #111}.signinpop .sp-go:active{transform:translate(3px,3px);box-shadow:0 0 0 #111}.signinpop .sp-go:disabled{opacity:.6;cursor:wait}
.signinpop .sp-err{min-height:1.3em;margin:8px 0 0;font:700 13px/1.35 'Bricolage Grotesque',system-ui,sans-serif;color:#d4260b}
.signinpop .sp-help{margin:6px 0 0;font:600 12.5px/1.4 'Bricolage Grotesque',system-ui,sans-serif;color:#6b6663}.signinpop .sp-help a{color:#2F5BFF;font-weight:800}
.signinpop .sp-ok{display:block;font:800 24px/1.1 'Bricolage Grotesque',system-ui,sans-serif;color:#13803b}
.signinpop.bad{animation:spshake .38s}
@keyframes spshake{20%{transform:translateX(-7px)}40%{transform:translateX(6px)}60%{transform:translateX(-4px)}80%{transform:translateX(3px)}}
@media(prefers-reduced-motion:reduce){.mcpop,.signinpop.bad{animation:none}.signinpop{transition:opacity .1s}}
header .signoutbtn,header .signoutbtn:hover{width:auto!important;padding:0 12px!important;font-size:13px;background:#fff;color:var(--hk-ink)}header .signoutbtn .ct{display:inline!important}