:root{
  --bg: #fafafa;
  --card: #ffffff;
  --text: #0f172a;
  --muted: #475569;
  --border: rgba(15,23,42,0.14);
  --shadow: 0 10px 30px rgba(2,6,23,0.08);
  --max: 78ch;
  --radius: 18px;
}

*{ box-sizing: border-box; }
html,body{ height:100%; }
body{
  margin:0;
  font-family: ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, Helvetica, Arial, "Apple Color Emoji","Segoe UI Emoji";
  color: var(--text);
  background: var(--bg);
  line-height: 1.65;
}

a{ color: inherit; text-decoration: underline; text-decoration-color: rgba(15,23,42,0.35); }
a:hover{ text-decoration-color: rgba(15,23,42,0.85); }

.paper-header{
  position: sticky;
  top: 0;
  z-index: 50;
  backdrop-filter: blur(10px);
  background: rgba(250,250,250,0.82);
  border-bottom: 1px solid var(--border);
}

.paper-header__inner{
  max-width: 1100px;
  margin: 0 auto;
  padding: 0.9rem 1rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.paper-brand{
  font-weight: 750;
  letter-spacing: -0.02em;
  text-decoration: none;
}

.paper-nav{
  display:flex;
  align-items:center;
  gap:0.75rem;
  color: var(--muted);
  font-size: 0.95rem;
}

.paper-nav a{ text-decoration: none; padding: 0.35rem 0.5rem; border-radius: 10px; }
.paper-nav a:hover{ background: rgba(15,23,42,0.06); color: var(--text); }

.paper-lang{
  border: 1px solid var(--border);
  background: var(--card);
  color: var(--text);
  padding: 0.35rem 0.6rem;
  border-radius: 999px;
  cursor: pointer;
  font-weight: 650;
}
.paper-lang:hover{ box-shadow: 0 6px 18px rgba(2,6,23,0.08); }

.paper-shell{
  max-width: 1100px;
  margin: 0 auto;
  padding: 1.6rem 1rem 2.5rem;
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.5rem;
}

@media (min-width: 980px){
  .paper-shell{
    grid-template-columns: minmax(0, 1fr) 280px;
    align-items: start;
  }
}

.paper-main{ min-width:0; }

.paper-article{
  max-width: var(--max);
}

.paper-article h1,
.paper-article h2,
.paper-article h3{
  font-family: ui-serif, Georgia, "Times New Roman", Times, serif;
  line-height: 1.18;
  letter-spacing: -0.015em;
}

.paper-article h1{ font-size: clamp(2rem, 4.5vw, 2.7rem); margin: 1.2rem 0 0.75rem; }
.paper-article h2{ font-size: 1.55rem; margin: 2.2rem 0 0.55rem; }
.paper-article h3{ font-size: 1.15rem; margin: 1.4rem 0 0.35rem; }

.paper-article p{ margin: 0.75rem 0; }
.paper-article ul, .paper-article ol{ padding-left: 1.3rem; }
.paper-article li{ margin: 0.25rem 0; }

.paper-article code{
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace;
  font-size: 0.95em;
  background: rgba(15,23,42,0.06);
  padding: 0.12em 0.3em;
  border-radius: 8px;
}

.paper-article pre{
  background: #0b1220;
  color: #e2e8f0;
  padding: 1rem;
  border-radius: var(--radius);
  overflow: auto;
  box-shadow: var(--shadow);
}
.paper-article pre code{ background: transparent; padding:0; color: inherit; }

.callout{
  border: 1px solid var(--border);
  border-left-width: 4px;
  border-radius: var(--radius);
  background: var(--card);
  padding: 1rem 1.05rem;
  box-shadow: 0 8px 22px rgba(2,6,23,0.06);
  margin: 1.1rem 0;
}
.callout .callout-title{
  font-weight: 750;
  margin-bottom: 0.35rem;
}
.callout--key{ border-left-color: rgba(15,23,42,0.9); }
.callout--warn{ border-left-color: rgba(220,38,38,0.9); }
.callout--model{ border-left-color: rgba(22,163,74,0.9); }

blockquote{
  margin: 1rem 0;
  padding: 0.2rem 1rem;
  border-left: 4px solid var(--border);
  color: var(--muted);
}

figure{
  margin: 1.3rem 0;
  padding: 1rem;
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: 0 8px 22px rgba(2,6,23,0.06);
}
figure img{ width:100%; height:auto; display:block; }
figcaption{ color: var(--muted); font-size: 0.92rem; margin-top: 0.6rem; }

.paper-aside{
  position: sticky;
  top: 74px;
  align-self: start;
  display: none;
}
@media (min-width: 980px){
  .paper-aside{ display: block; }
}

.paper-aside__box{
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: 0 8px 22px rgba(2,6,23,0.06);
  padding: 1rem;
  margin-bottom: 1rem;
}

.paper-aside__title{
  font-weight: 800;
  margin-bottom: 0.6rem;
  letter-spacing: -0.01em;
}

.paper-toc a{
  display:block;
  color: var(--muted);
  text-decoration: none;
  padding: 0.25rem 0.25rem;
  border-radius: 10px;
  font-size: 0.92rem;
}
.paper-toc a:hover{ background: rgba(15,23,42,0.06); color: var(--text); }
.paper-toc .lvl-3{ padding-left: 0.75rem; font-size: 0.88rem; }

.paper-actions{ display:flex; flex-direction:column; gap:0.5rem; }

.btn{
  border: 1px solid var(--border);
  background: var(--text);
  color: #fff;
  padding: 0.6rem 0.8rem;
  border-radius: 14px;
  cursor: pointer;
  font-weight: 700;
}
.btn:hover{ filter: brightness(1.05); }
.btn--ghost{
  background: var(--card);
  color: var(--text);
}
.btn--ghost:hover{ background: rgba(15,23,42,0.06); }

.paper-aside__hint{ margin: 0.7rem 0 0; color: var(--muted); font-size: 0.9rem; }

.lab-embed{
  margin: 1.2rem 0;
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  overflow: hidden;
}
.lab-embed__top{
  display:flex;
  justify-content: space-between;
  align-items:center;
  gap: 0.75rem;
  padding: 0.85rem 0.95rem;
  border-bottom: 1px solid var(--border);
}
.lab-embed__top .btn{ padding: 0.45rem 0.7rem; border-radius: 12px; font-size: 0.95rem; }
.lab-embed__frame{
  width: 100%;
  height: 860px;
  border: 0;
  display:block;
}
@media (max-width: 680px){
  .lab-embed__frame{ height: 950px; }
}

dialog{
  border: none;
  border-radius: 22px;
  width: min(920px, calc(100% - 2rem));
  padding: 0;
  box-shadow: 0 30px 80px rgba(2,6,23,0.25);
}
dialog::backdrop{ background: rgba(2,6,23,0.5); backdrop-filter: blur(3px); }

.modal{
  background: var(--card);
  border: 1px solid var(--border);
}
.modal-header{
  display:flex;
  justify-content: space-between;
  align-items: start;
  gap: 1rem;
  padding: 1.05rem 1.1rem 0.6rem;
  border-bottom: 1px solid var(--border);
}
.modal-title{ font-weight: 900; font-size: 1.15rem; margin: 0; }
.modal-close{
  border: 1px solid var(--border);
  background: var(--card);
  padding: 0.35rem 0.55rem;
  border-radius: 12px;
  cursor: pointer;
}
.modal-close:hover{ background: rgba(15,23,42,0.06); }

.modal-body{
  padding: 1rem 1.1rem 1.2rem;
  max-height: 75vh;
  overflow: auto;
}

.voice{
  border: 1px solid var(--border);
  border-radius: 18px;
  padding: 0.85rem 0.9rem;
  background: rgba(15,23,42,0.02);
  margin: 0.8rem 0;
}
.voice .who{
  font-weight: 850;
  margin-bottom: 0.35rem;
}
.voice .meta{
  color: var(--muted);
  font-size: 0.9rem;
  margin-top: 0.5rem;
}

.voice-actions{ margin-top: 0.6rem; display:flex; flex-wrap:wrap; gap: 0.5rem; }
.voice-actions button{ font-size: 0.92rem; padding: 0.4rem 0.6rem; border-radius: 12px; }

.refs{
  margin: 2rem 0 1rem;
  padding-top: 1.3rem;
  border-top: 1px solid var(--border);
}
.refs h2{ margin-top:0; }
.refs li{ margin: 0.5rem 0; color: var(--muted); }

.paper-footer{
  border-top: 1px solid var(--border);
  padding: 1.4rem 1rem;
  color: var(--muted);
}
.paper-footer__inner{
  max-width: 1100px;
  margin: 0 auto;
  display:flex;
  gap:0.5rem;
  align-items:center;
}
.paper-footer__sep{ opacity:0.6; }