/* ===== Tokens ===== */
:root {
  --bg: #f7f8fa;
  --surface: #ffffff;
  --surface-2: #f1f3f7;
  --border: #e2e6ee;
  --text: #1c2230;
  --text-2: #4d5768;
  --text-3: #7a8496;
  --accent: #2f6fed;
  --accent-soft: #e8f0ff;
  --ok: #14895a;
  --ok-soft: #e3f5ec;
  --rev: #c46a00;
  --rev-soft: #fff1dd;
  --danger: #c93a3a;
  --danger-soft: #fdeaea;
  --violet: #7347d8;
  --violet-soft: #f0eaff;
  --code-bg: #0f1522;
  --code-text: #dbe3f2;
  --mark: #fff1a8;
  --shadow: 0 1px 2px rgba(20, 30, 50, .06), 0 4px 16px rgba(20, 30, 50, .06);
  --radius: 10px;
  --sidebar-w: 300px;
  --top-h: 58px;
  --font: "Inter", "Segoe UI", system-ui, -apple-system, Roboto, sans-serif;
  --mono: "JetBrains Mono", "Cascadia Code", Consolas, "SFMono-Regular", Menlo, monospace;
  /* sintaxis */
  --hl-kw: #c792ea; --hl-str: #b5e08a; --hl-com: #6b7891; --hl-num: #f7a86b;
  --hl-type: #82c8ff; --hl-ann: #ffcb6b; --hl-var: #ff9cac; --hl-key: #7fdbca; --hl-fn: #8fb4ff;
  color-scheme: light;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #0e121a; --surface: #151b26; --surface-2: #1b2331; --border: #273142;
    --text: #e6eaf2; --text-2: #b3bccb; --text-3: #7e899c;
    --accent: #6b9bff; --accent-soft: #1b2a47;
    --ok: #3ecf8e; --ok-soft: #132f25; --rev: #ffb054; --rev-soft: #33260f;
    --danger: #ff7676; --danger-soft: #3a1818; --violet: #b195ff; --violet-soft: #261f3d;
    --code-bg: #0a0e15; --mark: #5a4b0e; --shadow: 0 1px 2px rgba(0,0,0,.3), 0 6px 20px rgba(0,0,0,.25);
    color-scheme: dark;
  }
}
:root[data-theme="dark"] {
  --bg: #0e121a; --surface: #151b26; --surface-2: #1b2331; --border: #273142;
  --text: #e6eaf2; --text-2: #b3bccb; --text-3: #7e899c;
  --accent: #6b9bff; --accent-soft: #1b2a47;
  --ok: #3ecf8e; --ok-soft: #132f25; --rev: #ffb054; --rev-soft: #33260f;
  --danger: #ff7676; --danger-soft: #3a1818; --violet: #b195ff; --violet-soft: #261f3d;
  --code-bg: #0a0e15; --mark: #5a4b0e; --shadow: 0 1px 2px rgba(0,0,0,.3), 0 6px 20px rgba(0,0,0,.25);
  color-scheme: dark;
}

/* ===== Base ===== */
* { box-sizing: border-box; }
html { overflow-x: hidden; scroll-padding-top: calc(var(--top-h) + 16px); }
body { margin: 0; background: var(--bg); color: var(--text); font: 15.5px/1.65 var(--font); -webkit-font-smoothing: antialiased; }
a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }
button { font: inherit; color: inherit; }
code { font-family: var(--mono); font-size: .86em; background: var(--surface-2); border: 1px solid var(--border); padding: .08em .38em; border-radius: 5px; }
mark { background: var(--mark); color: inherit; padding: 0 .15em; border-radius: 3px; }
hr { border: 0; border-top: 1px solid var(--border); margin: 2rem 0; }
h1, h2, h3, h4 { line-height: 1.25; letter-spacing: -.01em; }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; border-radius: 4px; }

/* ===== Topbar ===== */
.topbar { position: sticky; top: 0; z-index: 30; height: var(--top-h); display: flex; align-items: center; gap: 14px; padding: 0 16px; background: color-mix(in srgb, var(--surface) 88%, transparent); backdrop-filter: blur(10px); border-bottom: 1px solid var(--border); }
.brand { display: flex; align-items: center; gap: 10px; color: var(--text); font-weight: 700; min-width: calc(var(--sidebar-w) - 70px); }
.brand:hover { text-decoration: none; }
.brand-mark { width: 30px; height: 30px; border-radius: 8px; display: grid; place-items: center; background: var(--accent); color: #fff; font-weight: 800; }
.brand-text { display: flex; flex-direction: column; line-height: 1.1; }
.brand-text small { font-weight: 500; color: var(--text-3); font-size: 12px; }
.modes { display: flex; gap: 4px; }
.modes a { color: var(--text-2); padding: 7px 12px; border-radius: 8px; font-weight: 550; font-size: 14.5px; display: flex; align-items: center; gap: 6px; }
.modes a:hover { background: var(--surface-2); text-decoration: none; }
.modes a.active { background: var(--accent-soft); color: var(--accent); }
.pill { font-size: 11.5px; background: var(--rev-soft); color: var(--rev); border-radius: 99px; padding: 0 7px; font-weight: 700; }
.search { position: relative; margin-left: auto; display: flex; align-items: center; gap: 8px; background: var(--surface-2); border: 1px solid var(--border); border-radius: 9px; padding: 0 10px; width: min(380px, 40vw); color: var(--text-3); }
.search input { border: 0; background: transparent; color: var(--text); font: inherit; font-size: 14.5px; height: 36px; width: 100%; outline: none; }
.search-results { position: absolute; top: 44px; right: 0; width: min(560px, 92vw); max-height: 70vh; overflow: auto; background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); box-shadow: var(--shadow); padding: 6px; }
.sr-item { display: block; padding: 9px 11px; border-radius: 8px; color: var(--text); }
.sr-item:hover, .sr-item.sel { background: var(--accent-soft); text-decoration: none; }
.sr-item .sr-kind { font-size: 11px; text-transform: uppercase; letter-spacing: .05em; color: var(--text-3); font-weight: 700; }
.sr-item .sr-title { font-weight: 600; }
.sr-item .sr-snip { font-size: 13px; color: var(--text-2); display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden; }
.sr-empty { padding: 14px; color: var(--text-3); }
.icon-btn { background: transparent; border: 1px solid var(--border); width: 36px; height: 36px; border-radius: 9px; display: grid; place-items: center; cursor: pointer; color: var(--text-2); flex: none; }
.icon-btn:hover { background: var(--surface-2); }
.menu-btn { display: none; }

/* ===== Layout ===== */
.layout { display: flex; min-height: calc(100vh - var(--top-h)); }
.sidebar { width: var(--sidebar-w); flex: none; position: sticky; top: var(--top-h); height: calc(100vh - var(--top-h)); overflow-y: auto; border-right: 1px solid var(--border); background: var(--surface); padding: 14px 10px 40px; scrollbar-width: thin; }
.main { flex: 1; min-width: 0; padding: 28px 40px 80px; outline: none; }
.scrim { display: none; }

/* sidebar */
.nav-group { margin-bottom: 14px; }
.nav-group-title { font-size: 11.5px; text-transform: uppercase; letter-spacing: .07em; color: var(--text-3); font-weight: 700; padding: 6px 10px; }
.nav-sec > button { width: 100%; display: flex; align-items: center; gap: 8px; background: none; border: 0; text-align: left; padding: 7px 10px; border-radius: 8px; cursor: pointer; font-weight: 600; font-size: 14.5px; color: var(--text); }
.nav-sec > button:hover { background: var(--surface-2); }
.nav-sec > button .chev { transition: transform .15s; color: var(--text-3); flex: none; }
.nav-sec.open > button .chev { transform: rotate(90deg); }
.nav-sec > button .nav-title { flex: 1; }
.nav-sec.current > button { color: var(--accent); }
.ring { --p: 0; width: 18px; height: 18px; border-radius: 50%; flex: none; background: conic-gradient(var(--ok) calc(var(--p) * 1%), var(--border) 0); -webkit-mask: radial-gradient(circle 5px, transparent 98%, #000); mask: radial-gradient(circle 5px, transparent 98%, #000); }
.nav-topics { display: none; margin: 2px 0 6px 18px; border-left: 1px solid var(--border); padding-left: 6px; }
.nav-sec.open .nav-topics { display: block; }
.nav-topics a { display: flex; gap: 6px; align-items: baseline; padding: 4px 10px; border-radius: 7px; color: var(--text-2); font-size: 14px; line-height: 1.4; }
.nav-topics a:hover { background: var(--surface-2); text-decoration: none; color: var(--text); }
.nav-topics a.active { background: var(--accent-soft); color: var(--accent); font-weight: 600; }
.nav-topics a .read-dot { width: 6px; height: 6px; border-radius: 50%; background: transparent; flex: none; transform: translateY(-2px); }
.nav-topics a.read .read-dot { background: var(--ok); }
.nav-topics a .qn { margin-left: auto; font-size: 11.5px; color: var(--text-3); }

/* ===== Contenido ===== */
.page { max-width: 880px; width: 100%; margin: 0 auto; }
.page-wide { max-width: 1180px; width: 100%; margin: 0 auto; }
.with-toc { display: grid; grid-template-columns: minmax(0, 880px) 220px; gap: 40px; justify-content: center; }
.with-toc > *, .page, .prose, .q, .q-body, .flash { min-width: 0; }
.page h1, .q-text, .flash-q { overflow-wrap: anywhere; }
.toc { position: sticky; top: calc(var(--top-h) + 24px); align-self: start; font-size: 13.5px; max-height: calc(100vh - var(--top-h) - 48px); overflow: auto; }
.toc-title { font-size: 11.5px; text-transform: uppercase; letter-spacing: .07em; color: var(--text-3); font-weight: 700; margin-bottom: 8px; }
.toc a { display: block; color: var(--text-2); padding: 3px 0 3px 10px; border-left: 2px solid var(--border); line-height: 1.35; }
.toc a.h4 { padding-left: 22px; font-size: 13px; }
.toc a.active { color: var(--accent); border-left-color: var(--accent); }
.toc a:hover { text-decoration: none; color: var(--text); }

.crumbs { font-size: 13.5px; color: var(--text-3); margin-bottom: 6px; display: flex; gap: 6px; flex-wrap: wrap; }
.crumbs a { color: var(--text-3); }
.page h1 { font-size: 2.05rem; margin: 0 0 6px; }
.lead { font-size: 1.08rem; color: var(--text-2); margin: 0 0 22px; }
.topic-meta { display: flex; gap: 8px; flex-wrap: wrap; align-items: center; margin-bottom: 26px; }
.chip { display: inline-flex; align-items: center; gap: 5px; font-size: 12.5px; font-weight: 600; padding: 3px 10px; border-radius: 99px; background: var(--surface-2); color: var(--text-2); border: 1px solid var(--border); }
.btn { display: inline-flex; align-items: center; gap: 7px; padding: 8px 14px; border-radius: 9px; border: 1px solid var(--border); background: var(--surface); cursor: pointer; font-weight: 600; font-size: 14px; color: var(--text); }
.btn:hover { background: var(--surface-2); text-decoration: none; }
.btn.primary { background: var(--accent); border-color: var(--accent); color: #fff; }
.btn.primary:hover { filter: brightness(1.07); }
.btn.ok { color: var(--ok); }
.btn.ok.on { background: var(--ok-soft); border-color: var(--ok); }
.btn.rev { color: var(--rev); }
.btn.rev.on { background: var(--rev-soft); border-color: var(--rev); }
.btn.small { padding: 4px 10px; font-size: 13px; }

.prose h3 { font-size: 1.32rem; margin: 2.2rem 0 .7rem; padding-top: .3rem; }
.prose h4 { font-size: 1.08rem; margin: 1.6rem 0 .5rem; }
.prose h5 { font-size: .98rem; margin: 1.2rem 0 .4rem; color: var(--text-2); }
.prose p { margin: .7rem 0; }
.prose ul, .prose ol { padding-left: 1.4rem; margin: .6rem 0; }
.prose li { margin: .25rem 0; }
.prose li > ul, .prose li > ol { margin: .2rem 0; }
.prose blockquote { margin: 1rem 0; padding: .2rem 1rem; border-left: 3px solid var(--accent); color: var(--text-2); background: var(--surface); border-radius: 0 8px 8px 0; }
.prose strong { font-weight: 650; }
.prose a.xref { border-bottom: 1px dashed currentColor; }
.prose a.xref:hover { text-decoration: none; }

.table-wrap { overflow-x: auto; margin: 1rem 0; border: 1px solid var(--border); border-radius: var(--radius); background: var(--surface); }
table { border-collapse: collapse; width: 100%; font-size: 14px; }
th, td { text-align: left; padding: 9px 12px; border-bottom: 1px solid var(--border); vertical-align: top; }
th { background: var(--surface-2); font-weight: 650; white-space: nowrap; }
tr:last-child td { border-bottom: 0; }

.cols { display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap: 16px; margin: 1rem 0; }
.cols > div > :first-child { margin-top: 0; }

.callout { border: 1px solid var(--border); border-left: 4px solid var(--accent); background: var(--surface); border-radius: var(--radius); padding: 12px 16px; margin: 1.1rem 0; }
.callout > :last-child { margin-bottom: 0; }
.callout-title { font-weight: 700; font-size: 13.5px; text-transform: uppercase; letter-spacing: .04em; margin-bottom: 4px; color: var(--accent); }
.callout.tip { border-left-color: var(--ok); } .callout.tip .callout-title { color: var(--ok); }
.callout.warn { border-left-color: var(--rev); } .callout.warn .callout-title { color: var(--rev); }
.callout.trampa { border-left-color: var(--danger); } .callout.trampa .callout-title { color: var(--danger); }
.callout.corrige { border-left-color: var(--violet); background: var(--violet-soft); } .callout.corrige .callout-title { color: var(--violet); }
.callout.ejemplo { border-left-color: var(--hl-fn); }

/* código */
.code { margin: 1rem 0; border-radius: var(--radius); overflow: hidden; background: var(--code-bg); border: 1px solid #1f2838; }
.code-head { display: flex; justify-content: space-between; align-items: center; padding: 6px 8px 6px 14px; background: #151d2c; color: #8c99b0; font: 600 12px var(--mono); text-transform: lowercase; }
.copy { background: transparent; border: 1px solid #2c374b; color: #a9b5ca; border-radius: 6px; padding: 2px 9px; font-size: 12px; cursor: pointer; text-transform: none; }
.copy:hover { background: #222c3e; }
.code pre { margin: 0; padding: 14px 16px; overflow-x: auto; scrollbar-width: thin; }
.code pre code { background: none; border: 0; padding: 0; font-size: 13.3px; line-height: 1.6; color: var(--code-text); white-space: pre; }
.t-kw { color: var(--hl-kw); } .t-str { color: var(--hl-str); } .t-com { color: var(--hl-com); font-style: italic; }
.t-num { color: var(--hl-num); } .t-type { color: var(--hl-type); } .t-ann { color: var(--hl-ann); }
.t-var { color: var(--hl-var); } .t-key { color: var(--hl-key); } .t-fn { color: var(--hl-fn); }

/* preguntas */
.q { border: 1px solid var(--border); background: var(--surface); border-radius: var(--radius); margin: 1rem 0; box-shadow: var(--shadow); overflow: hidden; }
.q.ok { border-left: 4px solid var(--ok); }
.q.rev { border-left: 4px solid var(--rev); }
.q-head { display: flex; gap: 12px; align-items: flex-start; padding: 13px 16px; cursor: pointer; user-select: none; }
.q-head:hover { background: var(--surface-2); }
.q-icon { flex: none; width: 26px; height: 26px; border-radius: 7px; display: grid; place-items: center; background: var(--accent-soft); color: var(--accent); font-weight: 800; font-size: 13px; margin-top: 1px; }
.q-text { flex: 1; font-weight: 620; }
.q-level { flex: none; font-size: 11.5px; font-weight: 700; padding: 2px 8px; border-radius: 99px; text-transform: uppercase; letter-spacing: .04em; margin-top: 3px; }
.lv-junior { background: var(--ok-soft); color: var(--ok); }
.lv-mid { background: var(--accent-soft); color: var(--accent); }
.lv-senior { background: var(--violet-soft); color: var(--violet); }
.q-body { display: none; padding: 2px 18px 14px 54px; border-top: 1px dashed var(--border); }
.q.open .q-body { display: block; }
.q-actions { display: flex; gap: 8px; margin-top: 12px; flex-wrap: wrap; }

/* home */
.hero { background: linear-gradient(135deg, var(--accent-soft), var(--violet-soft)); border: 1px solid var(--border); border-radius: 16px; padding: 30px 32px; margin-bottom: 28px; }
.hero h1 { margin: 0 0 8px; font-size: 2.1rem; }
.hero p { margin: 0; color: var(--text-2); max-width: 720px; }
.stats { display: grid; grid-template-columns: repeat(auto-fit, minmax(160px, 1fr)); gap: 12px; margin: 20px 0 0; }
.stat { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 12px 16px; }
.stat b { display: block; font-size: 1.6rem; line-height: 1.2; }
.stat span { color: var(--text-3); font-size: 13px; }
.home-h2 { font-size: 1.25rem; margin: 30px 0 12px; display: flex; align-items: baseline; gap: 10px; }
.home-h2 small { font-weight: 500; color: var(--text-3); font-size: 13.5px; }
.cards { display: grid; grid-template-columns: repeat(auto-fill, minmax(260px, 1fr)); gap: 14px; }
.card { display: flex; flex-direction: column; gap: 6px; background: var(--surface); border: 1px solid var(--border); border-radius: 12px; padding: 16px 18px; color: var(--text); transition: border-color .15s, transform .15s; }
.card:hover { border-color: var(--accent); text-decoration: none; transform: translateY(-1px); }
.card h3 { margin: 0; font-size: 1.05rem; }
.card p { margin: 0; color: var(--text-2); font-size: 14px; flex: 1; }
.card .bar { height: 6px; border-radius: 99px; background: var(--surface-2); overflow: hidden; margin-top: 6px; }
.card .bar i { display: block; height: 100%; background: var(--ok); border-radius: 99px; }
.card .meta { font-size: 12.5px; color: var(--text-3); display: flex; justify-content: space-between; }
.checklist { list-style: none; padding: 0; margin: 0; display: grid; grid-template-columns: repeat(auto-fit, minmax(320px, 1fr)); gap: 10px; }
.checklist li { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 12px 14px; display: flex; gap: 10px; }
.checklist li b { display: block; }
.checklist li span { color: var(--text-2); font-size: 14px; }
.checklist .num { flex: none; width: 26px; height: 26px; border-radius: 7px; background: var(--accent); color: #fff; display: grid; place-items: center; font-weight: 700; font-size: 13px; }

/* sección */
.topic-list { display: grid; gap: 10px; margin-top: 18px; }
.topic-row { display: flex; align-items: center; gap: 14px; padding: 13px 16px; background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); color: var(--text); }
.topic-row:hover { border-color: var(--accent); text-decoration: none; }
.topic-row .idx { font: 700 13px var(--mono); color: var(--text-3); width: 26px; }
.topic-row .tt { flex: 1; font-weight: 600; }
.topic-row .tq { font-size: 12.5px; color: var(--text-3); }
.topic-row.read .idx { color: var(--ok); }

.pager { display: flex; justify-content: space-between; gap: 14px; margin-top: 48px; padding-top: 22px; border-top: 1px solid var(--border); }
.pager a { flex: 1; max-width: 48%; padding: 12px 16px; border: 1px solid var(--border); border-radius: var(--radius); background: var(--surface); color: var(--text); }
.pager a:hover { border-color: var(--accent); text-decoration: none; }
.pager a small { display: block; color: var(--text-3); font-size: 12.5px; }
.pager a.next { text-align: right; margin-left: auto; }

/* simulacro */
.quiz-setup { background: var(--surface); border: 1px solid var(--border); border-radius: 14px; padding: 20px 22px; }
.quiz-setup h3 { margin: 0 0 10px; font-size: 1rem; }
.opts { display: flex; flex-wrap: wrap; gap: 8px; margin-bottom: 16px; }
.opt { display: inline-flex; align-items: center; gap: 6px; padding: 6px 12px; border: 1px solid var(--border); border-radius: 99px; cursor: pointer; font-size: 14px; background: var(--surface); user-select: none; }
.opt input { accent-color: var(--accent); margin: 0; }
.opt:has(input:checked) { border-color: var(--accent); background: var(--accent-soft); color: var(--accent); }
.flash { background: var(--surface); border: 1px solid var(--border); border-radius: 16px; box-shadow: var(--shadow); padding: 26px 28px; margin-top: 18px; }
.flash-top { display: flex; justify-content: space-between; align-items: center; font-size: 13.5px; color: var(--text-3); margin-bottom: 14px; gap: 10px; flex-wrap: wrap; }
.flash-q { font-size: 1.35rem; font-weight: 650; line-height: 1.4; margin-bottom: 18px; }
.flash-a { border-top: 1px dashed var(--border); padding-top: 8px; }
.flash-bar { height: 5px; background: var(--surface-2); border-radius: 99px; overflow: hidden; margin-top: 16px; }
.flash-bar i { display: block; height: 100%; background: var(--accent); }
.kbd { font: 600 11.5px var(--mono); border: 1px solid var(--border); border-bottom-width: 2px; border-radius: 5px; padding: 0 5px; color: var(--text-3); }
.result { text-align: center; padding: 30px; }
.result b { font-size: 2.4rem; display: block; }

/* glosario */
.letters { display: flex; flex-wrap: wrap; gap: 4px; margin: 10px 0 20px; }
.letters a { width: 32px; height: 32px; display: grid; place-items: center; border: 1px solid var(--border); border-radius: 8px; color: var(--text-2); font-weight: 650; background: var(--surface); }
.gl-letter { font-size: 1.4rem; margin: 26px 0 8px; color: var(--accent); }
.gl { display: grid; grid-template-columns: 230px 1fr; gap: 6px 18px; padding: 11px 0; border-bottom: 1px solid var(--border); }
.gl dt { font-weight: 700; }
.gl dd { margin: 0; color: var(--text-2); }
.filter { width: 100%; max-width: 420px; padding: 9px 12px; border: 1px solid var(--border); border-radius: 9px; background: var(--surface); color: var(--text); font: inherit; }

.empty { text-align: center; color: var(--text-3); padding: 50px 20px; border: 1px dashed var(--border); border-radius: 14px; }

/* ===== Responsive ===== */
@media (max-width: 1280px) { .with-toc { grid-template-columns: minmax(0, 1fr); } .toc { display: none; } }
@media (max-width: 1000px) {
  .menu-btn { display: grid; }
  .brand { min-width: 0; }
  .sidebar { position: fixed; left: 0; top: var(--top-h); z-index: 40; transform: translateX(-100%); transition: transform .2s; box-shadow: var(--shadow); }
  body.nav-open .sidebar { transform: none; }
  body.nav-open .scrim { display: block; position: fixed; inset: var(--top-h) 0 0; background: rgba(0,0,0,.35); z-index: 35; }
  .main { padding: 22px 16px 70px; }
  .modes { display: none; }
  .search { width: auto; flex: 1; }
}
@media (max-width: 640px) {
  .brand-text { display: none; }
  .q-body { padding-left: 16px; }
  .gl { grid-template-columns: 1fr; }
  .hero { padding: 22px 18px; }
  .page h1, .hero h1 { font-size: 1.6rem; }
  .pager { flex-direction: column; }
  .pager a { max-width: none; }
  .flash { padding: 18px; }
}
@media (max-width: 1000px) { .mobile-modes { display: flex !important; } }
.mobile-modes { display: none; gap: 6px; flex-wrap: wrap; margin-bottom: 14px; }
.mobile-modes a { padding: 6px 12px; border: 1px solid var(--border); border-radius: 99px; color: var(--text-2); font-size: 14px; background: var(--surface); }
@media print { .topbar, .sidebar, .toc, .q-actions, .pager { display: none !important; } .q-body { display: block !important; } .main { padding: 0; } }