/* Shared desk styles (from FINAN IV Unit 5, 2026-11-02). */
:root{color-scheme:light;
  --bg:#F7F5F0;--surface:#FFFFFF;--panel:#EEEBE3;--line:#D9D4C8;--line-strong:#8A8475;
  --ink:#1B211D;--muted:#5C625D;--brand:#1C6B4A;--brand-ink:#FFFFFF;--brand-tint:#E2F0E8;
  --ok:#1C7340;--ok-tint:#E0F2E5;--bad:#A8261E;--bad-tint:#FBE7E4;--hint:#3B5469;--hint-tint:#E5ECF2;--focus:#1B211D;--hl:#FFF1B8;
  --serif:'Libre Caslon Text','Iowan Old Style',Georgia,serif;--display:'Libre Caslon Display','Libre Caslon Text',Georgia,serif;
  --mono:'IBM Plex Mono',ui-monospace,Menlo,Consolas,monospace;}
:root[data-theme="dark"]{color-scheme:dark;
  --bg:#121815;--surface:#18201C;--panel:#1F2924;--line:#2F3B35;--line-strong:#71807A;
  --ink:#E9EEEA;--muted:#AEBAB3;--brand:#7DD49A;--brand-ink:#0F1512;--brand-tint:#1B3326;
  --ok:#7DD49A;--ok-tint:#173324;--bad:#FF8D84;--bad-tint:#42201E;--hint:#A8BCCE;--hint-tint:#1C2A36;--focus:#E9EEEA;--hl:#4A4220;}
*{box-sizing:border-box}
[hidden]{display:none!important}
html,body{margin:0}
body{background:var(--bg);color:var(--ink);font:18px/1.6 var(--serif);font-variant-numeric:lining-nums tabular-nums}
a{color:var(--ink);text-underline-offset:.2em}
:focus-visible{outline:2.5px solid var(--focus);outline-offset:3px;border-radius:3px}
.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}
.skip{position:absolute;left:-9999px;top:0;background:var(--brand);color:var(--brand-ink);padding:.6rem 1rem;z-index:10}
.skip:focus{left:0}
header.bar{position:sticky;top:0;z-index:5;background:var(--bg);border-bottom:1px solid var(--line)}
.bar-in{max-width:820px;margin:0 auto;padding:.55rem 1.1rem;display:flex;align-items:center;gap:.7rem;flex-wrap:wrap}
.brand{font-style:italic;color:var(--muted);font-size:16px;margin-right:auto}
.brand b{font-style:normal;color:var(--brand);font-weight:700}
.btn-quiet{font:15px var(--serif);background:none;border:1px solid var(--line-strong);color:var(--ink);border-radius:6px;padding:.3rem .7rem;cursor:pointer}
.btn-quiet[aria-pressed="true"]{background:var(--ink);color:var(--bg);border-color:var(--ink)}
.btn-calc{font:700 15px var(--serif);background:var(--brand);color:var(--brand-ink);border:0;border-radius:6px;padding:.4rem .85rem;cursor:pointer}
aside.calc.inline{position:static;width:auto;max-width:30rem;box-shadow:none;margin:1.2rem 0 .4rem;border-color:var(--brand)}
nav.steps{max-width:820px;margin:0 auto;padding:0 1.1rem .55rem;overflow-x:auto}
nav.steps ol{display:flex;flex-wrap:wrap;gap:6px;list-style:none;margin:0;padding:0}
nav.steps button{font:14px var(--serif);border:1.5px solid var(--line-strong);background:var(--surface);color:var(--ink);border-radius:999px;padding:.2rem .7rem;cursor:pointer}
nav.steps button.done{background:var(--brand);border-color:var(--brand);color:var(--brand-ink)}
nav.steps button.done::before{content:"✓ "}
nav.steps button[aria-current="step"]{outline:2px solid var(--ink);outline-offset:2px}
.navnote{max-width:820px;margin:0 auto;padding:0 1.1rem .5rem;font-size:14px;color:var(--muted)}
main{max-width:820px;margin:0 auto;padding:1.2rem 1.1rem 7rem}
.kicker{font-style:italic;color:var(--muted);margin:1.6rem 0 .5rem;font-size:17px}
h1{font:400 clamp(40px,7vw,64px)/1 var(--display);letter-spacing:-.01em;margin:0 0 1rem}
.dek{font-style:italic;font-size:21px;line-height:1.45;color:var(--muted);max-width:34em;margin:0 0 1.6rem}
h2{font:400 30px/1.15 var(--display);margin:0 0 .5rem}
h3{font:700 18px var(--serif);margin:1.2rem 0 .3rem}
.place{font-style:italic;color:var(--muted);margin:0 0 .8rem}
.box{background:var(--panel);border-radius:8px;padding:1rem 1.25rem;margin:0 0 1.4rem}
.box p{margin:.3rem 0}.box ul{margin:.3rem 0;padding-left:1.2rem}.box li{margin:.25rem 0}
form.start{display:grid;gap:1rem;max-width:30rem}
label{display:block;font-weight:700;font-size:16px;margin-bottom:.25rem}
.field-help{font-size:15px;color:var(--muted);margin:.25rem 0 0}
input[type=text],input[type=email],textarea{width:100%;font:18px var(--serif);padding:.55rem .7rem;border:1.5px solid var(--line-strong);border-radius:6px;background:var(--surface);color:var(--ink)}
textarea{min-height:9rem;line-height:1.5}
input.money{font:500 19px var(--mono);width:14rem;max-width:100%;padding:.5rem .7rem;border:1.5px solid var(--line-strong);border-radius:6px;background:var(--surface);color:var(--ink)}
.btn{text-decoration:none;display:inline-block;font:700 17px var(--serif);background:var(--brand);color:var(--brand-ink);border:0;border-radius:7px;padding:.65rem 1.3rem;cursor:pointer}
.btn[disabled]{opacity:.5;cursor:not-allowed}
.btn.secondary{background:transparent;color:var(--ink);border:1.5px solid var(--line-strong)}
.btn.small{font-size:15px;padding:.4rem .9rem}
.memo{background:var(--surface);border:1px solid var(--line);border-radius:10px;padding:1.4rem 1.5rem 1.2rem;box-shadow:0 1px 0 var(--line)}
.memo-head{display:flex;justify-content:space-between;gap:1rem;flex-wrap:wrap;font-size:15px;color:var(--muted);border-bottom:1px solid var(--line);padding-bottom:.6rem;margin-bottom:1rem}
.memo-head b{color:var(--ink)}
.stamp{font:500 13px var(--mono);letter-spacing:.06em;text-transform:uppercase;border:1.5px solid currentColor;border-radius:4px;padding:.05rem .45rem;color:var(--brand)}
.memo p{margin:.5rem 0}
.tw{overflow-x:auto;max-width:100%}
table.cf{border-collapse:collapse;margin:1rem 0 .5rem;font:16px var(--mono);width:100%;max-width:44rem}
table.cf caption{text-align:left;font:italic 15px var(--serif);color:var(--muted);padding-bottom:.35rem}
table.cf th{font:700 14px var(--serif);text-align:right;padding:.35rem .6rem;border-bottom:1.5px solid var(--line-strong);vertical-align:bottom}
table.cf th:first-child,table.cf td:first-child{text-align:left}
table.cf td{text-align:right;padding:.3rem .6rem;border-bottom:1px solid var(--line);vertical-align:middle;white-space:nowrap}
table.cf tfoot td[colspan]{white-space:normal;text-align:left}
table.cf td.neg{color:var(--bad)}
table.cf td.lbl{font:16px var(--serif);white-space:normal;text-align:left}
table.cf td .ex{display:block;font-size:12.5px;color:var(--muted)}
table.cf input{font:15px var(--mono);width:9.5rem;text-align:right;padding:.2rem .35rem;border:1.5px solid var(--line-strong);border-radius:4px;background:var(--surface);color:var(--ink)}
table.cf input.good{border-color:var(--ok);background:var(--ok-tint)}
table.cf input.wrong{border-color:var(--bad);background:var(--bad-tint)}
table.cf input[readonly]{background:var(--panel);border-style:dashed}
table.cf .mark{display:inline-block;width:1.2em;text-align:center;font-family:var(--serif)}
table.cf tfoot td{border-bottom:0;padding-top:.45rem}
table.cf tfoot tr.total td{font-weight:500;border-top:1.5px solid var(--line-strong)}
table.cf tr.hl td{background:var(--hl)}
.reveal{animation:fade .35s ease}
@keyframes fade{from{opacity:0}to{opacity:1}}
@media (prefers-reduced-motion:reduce){.reveal{animation:none}}
.pair{display:grid;grid-template-columns:1fr 1fr;gap:1rem}
@media (max-width:680px){header.bar{position:static}.pair{grid-template-columns:1fr}table.cf{font-size:13px}table.cf input{width:6.4rem;font-size:13px}table.cf th,table.cf td{padding:.3rem .2rem}table.cf th{font-size:12.5px}.today{display:none}.memo{padding:1.1rem .8rem}table.cf .mark{width:.9em}}
.formula{font:500 16px var(--mono);background:var(--panel);border-radius:6px;padding:.6rem .8rem;margin:.6rem 0;line-height:1.7}.formula span{white-space:nowrap}
.ask{margin-top:1.2rem;display:grid;gap:1rem}
fieldset{border:0;padding:0;margin:0}
legend{font-weight:700;font-size:16px;margin-bottom:.35rem}
.choices{display:flex;gap:.6rem;flex-wrap:wrap}
.choices.stack{flex-direction:column;align-items:flex-start}
.choice{position:relative}
.choice input{position:absolute;opacity:0;inset:0}
.choice span{display:inline-block;border:1.5px solid var(--line-strong);border-radius:999px;padding:.35rem 1rem;font-size:16px;cursor:pointer;background:var(--surface)}
.choices.stack .choice span{border-radius:8px;text-align:left}
.choice input:checked + span{background:var(--ink);color:var(--bg);border-color:var(--ink)}
.choice input:focus-visible + span{outline:2.5px solid var(--focus);outline-offset:3px}
.actions{display:flex;gap:.8rem;align-items:center;flex-wrap:wrap;margin-top:.4rem}
.fb{border-radius:8px;padding:.8rem 1rem;margin-top:.8rem;font-size:17px}
.fb:empty{display:none}
.fb.ok{background:var(--ok-tint);border-left:4px solid var(--ok)}
.fb.bad{background:var(--bad-tint);border-left:4px solid var(--bad)}
.fb.hint{background:var(--hint-tint);border-left:4px solid var(--hint)}
.fb b{font-weight:700}
.attempts{font-size:14px;color:var(--muted)}
.q{border-top:1px solid var(--line);padding:1rem 0 .4rem}
.q:first-of-type{border-top:0}
.small{font-size:15px;color:var(--muted)}
.slider-wrap{margin:1rem 0}
input[type=range]{width:100%;max-width:30rem;accent-color:var(--brand)}
.readout{font:500 18px var(--mono)}
svg.curve{width:100%;max-width:36rem;height:auto;display:block;background:var(--panel);border-radius:8px;margin:.6rem 0}
svg.curve text{font:13px var(--serif);fill:var(--muted)}
.cert-preview{max-width:100%;border:1px solid var(--line);border-radius:6px;margin:1rem 0;display:block}
ul.check{list-style:none;padding:0;margin:.6rem 0 1rem}
ul.check li{display:flex;gap:.6rem;align-items:center;padding:.3rem 0;border-bottom:1px solid var(--line)}
ul.check .st{font:500 14px var(--mono);min-width:5.5rem}
ul.check .st.ok{color:var(--ok)}ul.check .st.no{color:var(--bad)}
.points{font:400 44px/1 var(--display);margin:.2rem 0 .6rem}
.wc{font-size:14px;color:var(--muted)}
/* calculator */
aside.calc{position:fixed;right:14px;bottom:14px;z-index:8;width:min(330px,calc(100vw - 28px));background:var(--surface);border:1.5px solid var(--line-strong);border-radius:12px;box-shadow:0 8px 30px rgba(0,0,0,.18);padding:.8rem}
aside.calc h2{font:700 16px var(--serif);margin:0}
.calc-top{display:flex;justify-content:space-between;align-items:center;margin-bottom:.5rem}
.calc input{width:100%;font:500 17px var(--mono);padding:.45rem .55rem;border:1.5px solid var(--line-strong);border-radius:6px;background:var(--bg);color:var(--ink)}
.calc-out{font:500 20px var(--mono);min-height:1.6em;margin:.4rem 0;text-align:right;word-break:break-all}
.calc-err{font-size:14px;color:var(--bad);min-height:1.2em}
.keys{display:grid;grid-template-columns:repeat(5,1fr);gap:5px}
.keys button{font:500 16px var(--mono);padding:.45rem 0;border:1px solid var(--line);border-radius:6px;background:var(--panel);color:var(--ink);cursor:pointer}
.keys button.op{background:var(--brand-tint)}
.keys button.eq{background:var(--brand);color:var(--brand-ink);border-color:var(--brand)}
footer{max-width:820px;margin:0 auto;padding:0 1.1rem 3rem;font-size:14px;color:var(--muted)}