:root{
  --bg:#f5f4f0; --surface:#fbfbf9; --panel:#ffffff; --panel-soft:#f7f6f2;
  --ink:#1c1c1a; --ink-hover:#3a3935; --ink-2:#55534d; --sub:#7a776f; --muted:#8a877f;
  --line:#e3e1db; --line-2:#dcdad3; --line-3:#efeee9; --hover:#efeee9; --soft:#f3f2ee; --track:#ebe9e3;
  --accent:#1f84c4; /* 공책 하늘색 */
  --accent-soft:#e4f1fa;
  --desk:#e9e7e1;
  --font:"IBM Plex Sans KR",sans-serif; --mono:"JetBrains Mono",monospace;
}
*{box-sizing:border-box}
[hidden]{display:none !important}
body{margin:0;background:var(--bg);color:var(--ink);font-family:var(--font);-webkit-font-smoothing:antialiased;word-break:keep-all}
button,select,input,textarea{font:inherit;color:inherit}
.mono-label{font-family:var(--mono);font-size:11px;letter-spacing:.12em;color:var(--muted)}
.app{min-height:100vh;display:flex;flex-direction:column}
.topbar{display:flex;align-items:center;justify-content:space-between;gap:16px;padding:16px 28px;border-bottom:1px solid var(--line);background:var(--surface);flex-wrap:wrap}
.brand{display:flex;align-items:baseline;gap:14px;min-width:0;flex-wrap:wrap}
.brand-title{font-size:17px;font-weight:700;letter-spacing:-.01em;margin:0}
.actions{display:flex;gap:8px}
.btn{height:36px;padding:0 14px;background:transparent;border:1px solid var(--line-2);border-radius:999px;font-size:13px;cursor:pointer;white-space:nowrap}
.btn:hover{background:var(--hover)}
.btn--solid{background:var(--ink);color:#fff;border:none;font-weight:500}
.btn--solid:hover{background:var(--ink-hover)}
.btn--lg{height:46px;width:100%;font-size:15px;background:var(--accent)}
.btn--lg:hover{background:#196fa6}
:focus-visible{outline:2px solid var(--accent);outline-offset:2px}
.sr-only{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap}

.wrap{width:100%;max-width:1320px;margin:0 auto;padding:24px 28px 56px;display:grid;grid-template-columns:minmax(0,380px) minmax(0,1fr);gap:24px;align-items:start}
.controls{display:flex;flex-direction:column;gap:12px;min-width:0}
.group{background:var(--panel);border:1px solid var(--line);border-radius:18px;padding:16px 16px 14px;display:flex;flex-direction:column;gap:12px}
.g-title{margin:0;font-size:14.5px}
.hint{margin:0;font-size:12px;color:var(--muted);line-height:1.5}
.presets-k{display:flex;flex-wrap:wrap;gap:6px}
.pk{height:30px;padding:0 12px;border-radius:999px;border:1px solid var(--line-2);background:var(--panel-soft);font-size:12.5px;cursor:pointer}
.pk:hover{border-color:var(--accent);background:var(--accent-soft)}
.pk[aria-pressed="true"]{background:var(--accent);border-color:var(--accent);color:#fff}
.ta{width:100%;min-height:150px;padding:10px 12px;border:1px solid var(--line-2);border-radius:12px;background:var(--surface);font-size:15px;line-height:1.6;resize:vertical}
.ta:focus,.sel:focus{outline:none;border-color:var(--accent)}
.styles{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:6px}
.st{position:relative;display:flex;flex-direction:column;align-items:center;gap:6px;padding:10px 4px 8px;border:1px solid var(--line-2);border-radius:12px;cursor:pointer;font-size:12px;text-align:center}
.st input{position:absolute;opacity:0}
.st:has(input:checked){border-color:var(--accent);background:var(--accent-soft);font-weight:700}
.st:has(input:focus-visible){outline:2px solid var(--accent)}
.st-ic{width:34px;height:34px;border:1.5px solid #8fb6d4;background:#fff}
.st-cross{background-image:linear-gradient(90deg,transparent calc(50% - .5px),#bcd3e4 calc(50% - .5px) calc(50% + .5px),transparent 0),linear-gradient(transparent calc(50% - .5px),#bcd3e4 calc(50% - .5px) calc(50% + .5px),transparent 0)}
.st-lined{border:none;background:linear-gradient(#8fb6d4,#8fb6d4) 0 6px/100% 1px no-repeat,repeating-linear-gradient(90deg,#bcd3e4 0 3px,transparent 3px 6px) 0 17px/100% 1px no-repeat,linear-gradient(#8fb6d4,#8fb6d4) 0 28px/100% 1.5px no-repeat,#fff}
.field{display:flex;flex-direction:column;gap:6px;font-size:12.5px;color:var(--sub);min-width:0}
.f-row{display:flex;justify-content:space-between;align-items:center}
.f-label small{color:var(--muted)}
.field input[type=range]{width:100%;accent-color:var(--accent)}
.tb-num-wrap{color:var(--sub)}
.sel{height:36px;padding:0 10px;border:1px solid var(--line-2);border-radius:10px;background:var(--surface);font-size:14px;color:var(--ink);width:100%;min-width:0}
.row2{display:grid;grid-template-columns:1fr 1fr;gap:8px}
.seg{display:flex;flex-wrap:wrap;background:var(--track);border-radius:12px;padding:3px;gap:2px}
.seg label{position:relative;flex:1 1 auto}
.seg input{position:absolute;opacity:0;pointer-events:none}
.seg span{display:block;text-align:center;height:30px;line-height:30px;padding:0 8px;border-radius:9px;font-size:12.5px;cursor:pointer;color:var(--ink-2);white-space:nowrap}
.seg input:checked + span{background:var(--panel);color:var(--ink);font-weight:700;box-shadow:0 1px 3px rgba(0,0,0,.12)}
.seg input:focus-visible + span{outline:2px solid var(--accent)}
.chk{display:flex;align-items:center;gap:8px;font-size:13px;color:var(--ink-2);cursor:pointer}
.chk input{accent-color:var(--accent);width:16px;height:16px;margin:0}
.fonts{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:6px}
.font-opt{border:1px solid var(--line-2);border-radius:10px;background:var(--surface);padding:7px 4px;cursor:pointer;display:flex;flex-direction:column;align-items:center;gap:1px;min-width:0}
.font-opt b{font-size:20px;font-weight:400;line-height:1.3}
.font-opt small{font-size:10.5px;color:var(--muted);white-space:nowrap}
.font-opt[aria-checked="true"]{border-color:var(--accent);background:var(--accent-soft)}
.colors{display:flex;gap:8px}
.cl{width:28px;height:28px;border-radius:8px;border:2px solid var(--c);background:#fff;cursor:pointer;background-image:linear-gradient(90deg,transparent calc(50% - .5px),var(--c) calc(50% - .5px) calc(50% + .5px),transparent 0)}
.cl[aria-checked="true"]{box-shadow:0 0 0 2px var(--panel),0 0 0 4px var(--ink)}
.print-box{background:var(--panel);border:1px solid var(--line);border-radius:18px;padding:16px;display:flex;flex-direction:column;gap:10px}
.count{margin:0;font-size:13px;color:var(--ink-2);font-weight:500}
.tip{font-size:12.5px;color:var(--sub)}
.tip summary{cursor:pointer}
.tip ol{margin:8px 0 0;padding-left:18px;line-height:1.7}

/* ---------- 미리보기 ---------- */
.preview-area{position:sticky;top:14px;background:var(--desk);border-radius:24px;padding:18px 20px 28px;min-width:0;background-image:radial-gradient(rgba(0,0,0,.05) 1px,transparent 1.2px);background-size:14px 14px}
.preview-head{display:flex;justify-content:space-between;align-items:center;gap:10px;margin-bottom:14px;flex-wrap:wrap}
.preview-note{font-size:12px;color:var(--sub)}
.preview{display:flex;flex-wrap:wrap;gap:20px;justify-content:center}
.thumb{position:relative;flex:none;background:#fff;box-shadow:0 1px 2px rgba(0,0,0,.1),0 16px 34px -16px rgba(0,0,0,.35);overflow:hidden}
.thumb-scale{transform-origin:0 0;position:absolute;left:0;top:0}
.thumb-no{position:absolute;right:8px;bottom:-22px;font-size:11px;color:var(--sub);font-family:var(--mono)}
.thumb-wrap{display:flex;flex-direction:column;align-items:center;gap:6px}
.thumb-cap{font-size:11px;color:var(--sub);font-family:var(--mono)}

/* ---------- 학습지 (종이, mm 단위) ---------- */
.pg{width:210mm;height:297mm;background:#fff;color:#1c1c1a;padding:13mm 14mm 10mm;display:flex;flex-direction:column;position:relative;overflow:hidden;-webkit-print-color-adjust:exact;print-color-adjust:exact;font-family:var(--wf)}
.ws-head{display:flex;align-items:flex-end;justify-content:space-between;gap:6mm;padding-bottom:3mm;margin-bottom:4mm;border-bottom:.5mm solid var(--lc)}
.ws-title{font-size:8mm;font-weight:700;letter-spacing:.3mm;line-height:1.1;margin:0;color:#1c1c1a;white-space:nowrap;overflow:hidden;text-overflow:ellipsis;min-width:0}
.ws-meta{display:flex;align-items:flex-end;gap:5mm;flex:none}
.ws-field{display:flex;align-items:flex-end;gap:1.5mm;font-size:3.6mm;color:#55534d;font-family:"IBM Plex Sans KR",sans-serif}
.ws-field i{display:block;width:26mm;border-bottom:.3mm solid #8a877f;height:5mm}
.ws-field i.sm{width:9mm}
.ws-stamp{width:17mm;height:17mm;border:.4mm dashed var(--lc);border-radius:50%;display:grid;place-items:center;font-size:3mm;color:var(--lc);font-family:"IBM Plex Sans KR",sans-serif;flex:none}
.ws-body{flex:1;display:flex;flex-direction:column;align-items:center;min-height:0}
.ws-foot{height:5mm;display:flex;align-items:flex-end;justify-content:center;font-size:2.8mm;color:#9a978f;font-family:"JetBrains Mono",monospace}
.r{display:grid;grid-template-columns:repeat(var(--cols),var(--s));flex:none}
.r.gap{margin-bottom:var(--gap)}
.c{position:relative;width:var(--s);height:var(--s);border-right:.3mm solid var(--lc);border-bottom:.3mm solid var(--lc);display:grid;place-items:center;font-size:var(--fs);line-height:1;font-family:var(--wf)}
.r > .c:first-child{border-left:.3mm solid var(--lc)}
.r.top > .c{border-top:.3mm solid var(--lc)}
.cross .c::before,.cross .c::after{content:"";position:absolute;pointer-events:none}
.cross .c::before{left:0;right:0;top:50%;border-top:.2mm dashed var(--lg)}
.cross .c::after{top:0;bottom:0;left:50%;border-left:.2mm dashed var(--lg)}
.c span{position:relative;z-index:1;transform:translateY(var(--dy))}
.k-d{color:#1c1c1a}
.k-g{color:var(--tc)}
.outline .k-g{color:transparent;-webkit-text-stroke:.28mm var(--tc)}
/* 줄 공책 */
.ln{width:var(--lw);height:var(--s);position:relative;flex:none;display:flex;align-items:center;font-size:var(--fs);line-height:1;padding-left:1mm;white-space:pre;font-family:var(--wf)}
.ln::before{content:"";position:absolute;left:0;right:0;top:12%;border-top:.25mm solid var(--lg)}
.ln::after{content:"";position:absolute;left:0;right:0;top:56%;border-top:.2mm dashed var(--lg)}
.ln{border-bottom:.35mm solid var(--lc)}
.ln.gap{margin-bottom:var(--gap)}
.ln span{position:relative;z-index:1;letter-spacing:var(--ls);transform:translateY(var(--dy))}

/* 인쇄 */
#printRoot{display:none}
@media print{
  html,body{background:#fff !important;margin:0 !important;padding:0 !important}
  body > *:not(#printRoot){display:none !important}
  #printRoot{display:block !important}
  #printRoot .pg{break-after:page;page-break-after:always;margin:0;box-shadow:none}
  #printRoot .pg:last-child{break-after:auto;page-break-after:auto}
}

@media (max-width:900px){
  .wrap{grid-template-columns:minmax(0,1fr)}
  .preview-area{order:-1;position:static}
}
@media (max-width:640px){
  .topbar{padding:14px 16px}
  .wrap{padding:14px 16px 32px;gap:16px}
  .preview-area{padding:14px 12px 30px;border-radius:18px}
  .fonts{grid-template-columns:repeat(2,minmax(0,1fr))}
}

/* 다크 모드 (학습지 미리보기 · 인쇄는 종이 그대로) */
@media screen{
  :root[data-theme="dark"]{
    color-scheme:dark;
    --bg:#121518; --surface:#181c20; --panel:#1d2227; --panel-soft:#22282e;
    --ink:#e8edf1; --ink-hover:#ffffff; --ink-2:#c3cbd2; --sub:#9aa5ae; --muted:#86919a;
    --line:#2a3138; --line-2:#363e46; --line-3:#232a30; --hover:#283037; --soft:#232a30; --track:#2e363e;
    --accent:#62b6ea; --accent-soft:rgba(98,182,234,.14);
    --desk:#171b1f;
  }
  :root[data-theme="dark"] .tb-presets button[aria-pressed="true"],
  :root[data-theme="dark"] .btn--solid,
  :root[data-theme="dark"] .pk[aria-pressed="true"],
  :root[data-theme="dark"] .toast{color:var(--bg)}
  :root[data-theme="dark"] .btn--lg{background:var(--accent);color:#0b1720}
  :root[data-theme="dark"] .btn--lg:hover{background:#82c6f0}
  :root[data-theme="dark"] .seg input:checked + span{background:var(--line-2);box-shadow:0 1px 3px rgba(0,0,0,.4)}
  :root[data-theme="dark"] .preview-area{background-image:radial-gradient(rgba(255,255,255,.05) 1px,transparent 1.2px);box-shadow:inset 0 0 0 1px var(--line)}
  :root[data-theme="dark"] .thumb{box-shadow:0 1px 2px rgba(0,0,0,.4),0 16px 34px -16px rgba(0,0,0,.8)}
  :root[data-theme="dark"] .st-ic,:root[data-theme="dark"] .cl{background-color:var(--panel-soft)}
  :root[data-theme="dark"] .st-lined{background-color:var(--panel-soft)}
  :root[data-theme="dark"] .cl[aria-checked="true"]{box-shadow:0 0 0 2px var(--panel),0 0 0 4px var(--ink)}
}

.toast{position:fixed;left:50%;bottom:28px;transform:translate(-50%,20px);background:var(--ink);color:#fff;padding:10px 18px;border-radius:999px;font-size:13px;opacity:0;pointer-events:none;transition:opacity .2s,transform .2s;z-index:80}
.toast.is-on{opacity:1;transform:translate(-50%,0)}
@media (prefers-reduced-motion:reduce){ .toast{transition:none} }