/* Cálculo Estrutural · Prof. Luiz Mantovani — folha de estilo única.
   Paleta de "papel de engenharia": tinta escura, violeta para o que é do aluno mexer,
   laranja para reações, verde para cargas. Tema claro e escuro pelos mesmos tokens. */

:root {
  color-scheme: light;
  --papel: #F6F4EF; --papel-2: #EFECE4; --cartao: #FFFFFF; --cartao-2: #FBFAF7;
  --tinta: #1B1F27; --tinta-2: #4B5263; --tinta-3: #838996;
  --linha: #E4E0D7; --linha-2: #CFCABF;
  --acento: #5B4FD1; --acento-forte: #4336B8; --acento-bg: #ECEAFB; --acento-bg-2: #DEDAF8;
  --reacao: #D2542E; --reacao-bg: #FBE8E1;
  --carga: #178A68; --carga-bg: #E1F3EC;
  --ok: #178A68; --ok-bg: #E1F3EC; --erro: #C23F28; --erro-bg: #FBE7E1; --aviso: #A86A12; --aviso-bg: #FBF0DC;
  --apoio: #C9CDD4;
  --sombra: 0 1px 2px rgba(27, 31, 39, .05), 0 4px 16px rgba(27, 31, 39, .06);
  --sombra-2: 0 2px 4px rgba(27, 31, 39, .06), 0 12px 32px rgba(27, 31, 39, .10);
  --raio: 14px; --raio-p: 9px;
  --sans: 'IBM Plex Sans', system-ui, -apple-system, 'Segoe UI', sans-serif;
  --serif: 'IBM Plex Serif', Georgia, 'Times New Roman', serif;
  --mono: 'IBM Plex Mono', ui-monospace, 'SFMono-Regular', Menlo, monospace;
  --largura: 1180px; --texto: 70ch;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-tema="claro"]) {
    color-scheme: dark;
    --papel: #13151A; --papel-2: #181B21; --cartao: #1C1F26; --cartao-2: #20242C;
    --tinta: #ECEDF0; --tinta-2: #B2B7C2; --tinta-3: #7F8593;
    --linha: #2B2F38; --linha-2: #3C414C;
    --acento: #9E95F2; --acento-forte: #B7B0F7; --acento-bg: #27234A; --acento-bg-2: #332E60;
    --reacao: #F28460; --reacao-bg: #43231A; --carga: #4DC49E; --carga-bg: #173A2F;
    --ok: #4DC49E; --ok-bg: #173A2F; --erro: #F28460; --erro-bg: #45221A; --aviso: #E3AE55; --aviso-bg: #3D2F14;
    --apoio: #4A505C;
    --sombra: 0 1px 2px rgba(0, 0, 0, .3), 0 4px 16px rgba(0, 0, 0, .25);
    --sombra-2: 0 2px 4px rgba(0, 0, 0, .35), 0 12px 32px rgba(0, 0, 0, .35);
  }
}
:root[data-tema="escuro"] {
  color-scheme: dark;
  --papel: #13151A; --papel-2: #181B21; --cartao: #1C1F26; --cartao-2: #20242C;
  --tinta: #ECEDF0; --tinta-2: #B2B7C2; --tinta-3: #7F8593;
  --linha: #2B2F38; --linha-2: #3C414C;
  --acento: #9E95F2; --acento-forte: #B7B0F7; --acento-bg: #27234A; --acento-bg-2: #332E60;
  --reacao: #F28460; --reacao-bg: #43231A; --carga: #4DC49E; --carga-bg: #173A2F;
  --ok: #4DC49E; --ok-bg: #173A2F; --erro: #F28460; --erro-bg: #45221A; --aviso: #E3AE55; --aviso-bg: #3D2F14;
  --apoio: #4A505C;
  --sombra: 0 1px 2px rgba(0, 0, 0, .3), 0 4px 16px rgba(0, 0, 0, .25);
  --sombra-2: 0 2px 4px rgba(0, 0, 0, .35), 0 12px 32px rgba(0, 0, 0, .35);
}

*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
body {
  margin: 0; background: var(--papel); color: var(--tinta);
  font: 400 17px/1.65 var(--sans); font-feature-settings: "kern", "liga";
  -webkit-font-smoothing: antialiased; text-rendering: optimizeLegibility;
  min-height: 100vh; display: flex; flex-direction: column;
}
main { flex: 1; }
img, svg, video { max-width: 100%; }
a { color: var(--acento); text-decoration-thickness: 1px; text-underline-offset: 3px; }
a:hover { color: var(--acento-forte); }
::selection { background: var(--acento-bg-2); }
:focus-visible { outline: 2px solid var(--acento); outline-offset: 2px; border-radius: 4px; }
hr { border: 0; border-top: 1px solid var(--linha); margin: 2rem 0; }
code, kbd { font-family: var(--mono); font-size: .88em; background: var(--papel-2); padding: .1em .4em; border-radius: 5px; }
.oculto { position: absolute !important; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; }
[hidden] { display: none !important; }

h1, h2, h3, h4 { line-height: 1.2; text-wrap: balance; margin: 0 0 .5em; color: var(--tinta); }
h1 { font: 600 clamp(2rem, 4.2vw, 3.1rem)/1.1 var(--serif); letter-spacing: -.02em; }
h2 { font: 600 clamp(1.5rem, 2.6vw, 2rem)/1.2 var(--serif); letter-spacing: -.01em; }
h3 { font: 600 1.2rem/1.3 var(--sans); }
h4 { font: 600 1rem/1.3 var(--sans); }
p { margin: 0 0 1em; }
.sobre { font: 500 .78rem/1 var(--mono); letter-spacing: .09em; text-transform: uppercase; color: var(--tinta-3); }
.lead { font-size: 1.18rem; color: var(--tinta-2); max-width: 60ch; }
.suave { color: var(--tinta-2); }
.fraco { color: var(--tinta-3); font-size: .92rem; }
.num { font-family: var(--mono); font-variant-numeric: tabular-nums; }

.conteiner { width: 100%; max-width: var(--largura); margin: 0 auto; padding: 0 20px; }
.estreito { max-width: 760px; }
.secao { padding: 72px 0; }
.secao-p { padding: 40px 0; }

/* ---------- topo ---------- */
.topo { position: sticky; top: 0; z-index: 30; background: color-mix(in srgb, var(--papel) 86%, transparent); backdrop-filter: saturate(1.4) blur(10px); -webkit-backdrop-filter: saturate(1.4) blur(10px); border-bottom: 1px solid var(--linha); }
.topo .conteiner { display: flex; align-items: center; gap: 20px; height: 64px; }
.marca { display: flex; align-items: center; gap: 11px; text-decoration: none; color: var(--tinta); margin-right: auto; }
.marca:hover { color: var(--tinta); }
.marca svg { flex: none; }
.marca-nome { display: flex; flex-direction: column; line-height: 1.15; }
.marca-nome b { font: 600 1.02rem var(--serif); letter-spacing: -.01em; }
.marca-nome span { font: 500 .72rem var(--mono); color: var(--tinta-3); letter-spacing: .04em; }
.nav { display: flex; align-items: center; gap: 4px; }
.nav a { color: var(--tinta-2); text-decoration: none; font-weight: 500; font-size: .95rem; padding: 8px 12px; border-radius: 8px; }
.nav a:hover, .nav a[aria-current="page"] { color: var(--tinta); background: var(--papel-2); }
.btn-tema { background: none; border: 1px solid var(--linha); color: var(--tinta-2); width: 38px; height: 38px; border-radius: 10px; display: grid; place-items: center; cursor: pointer; }
.btn-tema:hover { color: var(--tinta); border-color: var(--linha-2); }
.menu-conta { position: relative; }
.menu-conta summary { list-style: none; cursor: pointer; display: flex; align-items: center; gap: 8px; padding: 5px 10px 5px 5px; border: 1px solid var(--linha); border-radius: 999px; font-weight: 500; font-size: .92rem; }
.menu-conta summary::-webkit-details-marker { display: none; }
.avatar { width: 28px; height: 28px; border-radius: 50%; background: var(--acento-bg); color: var(--acento-forte); display: grid; place-items: center; font: 600 .82rem var(--sans); }
.menu-conta .caixa { position: absolute; right: 0; top: calc(100% + 8px); min-width: 230px; background: var(--cartao); border: 1px solid var(--linha); border-radius: 12px; box-shadow: var(--sombra-2); padding: 6px; }
.menu-conta .caixa a, .menu-conta .caixa button { display: block; width: 100%; text-align: left; padding: 9px 12px; border-radius: 8px; color: var(--tinta); text-decoration: none; background: none; border: 0; font: inherit; font-size: .95rem; cursor: pointer; }
.menu-conta .caixa a:hover, .menu-conta .caixa button:hover { background: var(--papel-2); }
.menu-conta .caixa .sep { border-top: 1px solid var(--linha); margin: 6px 0; }
.btn-menu { display: none; }
@media (max-width: 860px) {
  .nav { display: none; position: absolute; top: 64px; left: 0; right: 0; flex-direction: column; align-items: stretch; background: var(--cartao); border-bottom: 1px solid var(--linha); padding: 10px 16px 16px; box-shadow: var(--sombra-2); }
  .nav.aberto { display: flex; }
  .btn-menu { display: grid; }
  .marca-nome span { display: none; }
}

/* ---------- botões e formulários ---------- */
.btn { display: inline-flex; align-items: center; justify-content: center; gap: 8px; font: 600 .98rem/1 var(--sans); padding: 13px 20px; border-radius: 11px; border: 1px solid transparent; cursor: pointer; text-decoration: none; transition: background .15s, border-color .15s, color .15s, transform .08s, box-shadow .15s; white-space: nowrap; }
.btn:active { transform: translateY(1px); }
.btn-primario { background: var(--acento); color: #fff; box-shadow: 0 1px 0 rgba(255,255,255,.15) inset, 0 6px 18px color-mix(in srgb, var(--acento) 30%, transparent); }
.btn-primario:hover { background: var(--acento-forte); color: #fff; }
:root[data-tema="escuro"] .btn-primario, :root:not([data-tema="claro"]) .btn-primario { color: #fff; }
.btn-secundario { background: var(--cartao); color: var(--tinta); border-color: var(--linha-2); }
.btn-secundario:hover { border-color: var(--tinta-3); color: var(--tinta); }
.btn-fantasma { background: transparent; color: var(--tinta-2); }
.btn-fantasma:hover { background: var(--papel-2); color: var(--tinta); }
.btn-perigo { background: var(--cartao); color: var(--erro); border-color: color-mix(in srgb, var(--erro) 40%, transparent); }
.btn-perigo:hover { background: var(--erro-bg); color: var(--erro); }
.btn-p { padding: 9px 14px; font-size: .9rem; border-radius: 9px; }
.btn-g { padding: 16px 26px; font-size: 1.05rem; border-radius: 13px; }
.btn[disabled], .btn[aria-disabled="true"] { opacity: .55; pointer-events: none; }
.btn-bloco { width: 100%; }

.campo { display: flex; flex-direction: column; gap: 6px; margin-bottom: 16px; }
.campo label, .rotulo { font-weight: 600; font-size: .92rem; color: var(--tinta); }
.campo .ajuda { font-size: .85rem; color: var(--tinta-3); }
input[type=text], input[type=email], input[type=password], input[type=number], input[type=search], input[type=date], select, textarea {
  font: 400 1rem/1.4 var(--sans); color: var(--tinta); background: var(--cartao); border: 1px solid var(--linha-2);
  border-radius: 10px; padding: 11px 13px; width: 100%; transition: border-color .15s, box-shadow .15s;
}
textarea { min-height: 110px; resize: vertical; }
input:focus, select:focus, textarea:focus { outline: none; border-color: var(--acento); box-shadow: 0 0 0 4px color-mix(in srgb, var(--acento) 18%, transparent); }
input[aria-invalid="true"] { border-color: var(--erro); }
.check { display: flex; gap: 10px; align-items: flex-start; font-size: .93rem; color: var(--tinta-2); }
.check input { margin-top: 4px; accent-color: var(--acento); }
input[type=range] { accent-color: var(--acento); width: 100%; }

.alerta { padding: 12px 16px; border-radius: 11px; font-size: .95rem; border: 1px solid; margin-bottom: 18px; display: flex; gap: 10px; align-items: flex-start; }
.alerta-erro { background: var(--erro-bg); border-color: color-mix(in srgb, var(--erro) 35%, transparent); color: var(--tinta); }
.alerta-ok { background: var(--ok-bg); border-color: color-mix(in srgb, var(--ok) 35%, transparent); color: var(--tinta); }
.alerta-info { background: var(--acento-bg); border-color: color-mix(in srgb, var(--acento) 30%, transparent); color: var(--tinta); }
.alerta-aviso { background: var(--aviso-bg); border-color: color-mix(in srgb, var(--aviso) 35%, transparent); color: var(--tinta); }

/* ---------- cartões e grades ---------- */
.cartao { background: var(--cartao); border: 1px solid var(--linha); border-radius: var(--raio); box-shadow: var(--sombra); padding: 24px; }
.cartao-p { padding: 18px; }
.grade { display: grid; gap: 20px; }
.grade-2 { grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); }
.grade-3 { grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); }
.grade-4 { grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); }
.selo { display: inline-flex; align-items: center; gap: 6px; font: 600 .74rem/1 var(--mono); letter-spacing: .05em; text-transform: uppercase; padding: 5px 9px; border-radius: 999px; background: var(--acento-bg); color: var(--acento-forte); }
.selo-ok { background: var(--ok-bg); color: var(--ok); }
.selo-aviso { background: var(--aviso-bg); color: var(--aviso); }
.selo-erro { background: var(--erro-bg); color: var(--erro); }
.selo-neutro { background: var(--papel-2); color: var(--tinta-2); }

/* ---------- página inicial ---------- */
.heroi { padding: 64px 0 40px; position: relative; overflow: hidden; }
.heroi .conteiner { display: grid; grid-template-columns: 1.05fr 1fr; gap: 48px; align-items: center; }
.heroi h1 { font-size: clamp(2.2rem, 4.6vw, 3.5rem); }
.heroi h1 em { font-style: italic; color: var(--acento); }
.heroi .acoes { display: flex; gap: 12px; flex-wrap: wrap; margin-top: 28px; }
.heroi .prova { display: flex; gap: 22px; flex-wrap: wrap; margin-top: 28px; color: var(--tinta-2); font-size: .92rem; }
.heroi .prova b { display: block; font: 600 1.4rem var(--serif); color: var(--tinta); }
.heroi-figura { background: var(--cartao); border: 1px solid var(--linha); border-radius: 20px; box-shadow: var(--sombra-2); padding: 18px 18px 10px; position: relative; }
.heroi-figura .barra-ctl { display: flex; gap: 6px; flex-wrap: wrap; margin-bottom: 6px; }
.heroi-figura .legenda { font: 500 .78rem var(--mono); color: var(--tinta-3); display: flex; justify-content: space-between; margin-top: 4px; }
.grade-papel { position: absolute; inset: 0; z-index: -1; background-image: linear-gradient(var(--linha) 1px, transparent 1px), linear-gradient(90deg, var(--linha) 1px, transparent 1px); background-size: 28px 28px; mask-image: radial-gradient(ellipse at 70% 30%, #000 10%, transparent 70%); -webkit-mask-image: radial-gradient(ellipse at 70% 30%, #000 10%, transparent 70%); opacity: .55; }
@media (max-width: 920px) { .heroi .conteiner { grid-template-columns: 1fr; } }

.pilar { display: flex; flex-direction: column; gap: 10px; }
.pilar .icone { width: 44px; height: 44px; border-radius: 12px; display: grid; place-items: center; background: var(--acento-bg); color: var(--acento-forte); }
.pilar h3 { margin: 4px 0 0; }
.pilar p { color: var(--tinta-2); margin: 0; font-size: .98rem; }

.faixa { background: var(--cartao); border-top: 1px solid var(--linha); border-bottom: 1px solid var(--linha); }
.titulo-secao { max-width: 720px; margin-bottom: 36px; }
.titulo-secao p { color: var(--tinta-2); font-size: 1.08rem; }

.ementa { counter-reset: aula; display: grid; grid-template-columns: repeat(auto-fit, minmax(330px, 1fr)); gap: 12px; }
.ementa li { list-style: none; display: grid; grid-template-columns: 42px 1fr; gap: 12px; align-items: start; padding: 14px 16px; background: var(--cartao); border: 1px solid var(--linha); border-radius: 12px; }
.ementa li::before { counter-increment: aula; content: counter(aula, decimal-leading-zero); font: 600 .9rem var(--mono); color: var(--acento); background: var(--acento-bg); border-radius: 9px; height: 34px; display: grid; place-items: center; }
.ementa b { display: block; font-weight: 600; }
.ementa span { color: var(--tinta-3); font-size: .9rem; }
.ementa { padding: 0; margin: 0; }

.planos { display: grid; grid-template-columns: repeat(auto-fit, minmax(290px, 1fr)); gap: 22px; max-width: 820px; margin: 0 auto; }
.plano { position: relative; display: flex; flex-direction: column; gap: 14px; }
.plano.destaque { border: 2px solid var(--acento); box-shadow: var(--sombra-2); }
.plano .fita { position: absolute; top: -13px; left: 24px; }
.plano .preco { font: 600 2.6rem/1 var(--serif); letter-spacing: -.02em; }
.plano .preco small { font: 500 1rem var(--sans); color: var(--tinta-3); letter-spacing: 0; }
.plano ul { list-style: none; padding: 0; margin: 0; display: grid; gap: 9px; }
.plano li { display: grid; grid-template-columns: 20px 1fr; gap: 8px; color: var(--tinta-2); font-size: .96rem; }
.plano li::before { content: "✓"; color: var(--ok); font-weight: 700; }

.perguntas details { border-bottom: 1px solid var(--linha); padding: 16px 0; }
.perguntas summary { cursor: pointer; font-weight: 600; list-style: none; display: flex; justify-content: space-between; gap: 16px; }
.perguntas summary::after { content: "+"; font: 400 1.4rem/1 var(--sans); color: var(--tinta-3); }
.perguntas details[open] summary::after { content: "−"; }
.perguntas details p { color: var(--tinta-2); margin: 12px 0 0; }

.professor { display: grid; grid-template-columns: 180px 1fr; gap: 32px; align-items: center; }
.professor .retrato { width: 180px; height: 180px; border-radius: 24px; background: linear-gradient(135deg, var(--acento-bg-2), var(--carga-bg)); display: grid; place-items: center; font: 600 3.4rem var(--serif); color: var(--acento-forte); }
@media (max-width: 640px) { .professor { grid-template-columns: 1fr; } }

/* ---------- rodapé ---------- */
.rodape { border-top: 1px solid var(--linha); padding: 36px 0 44px; color: var(--tinta-3); font-size: .9rem; margin-top: 40px; }
.rodape .conteiner { display: flex; gap: 24px; flex-wrap: wrap; justify-content: space-between; }
.rodape a { color: var(--tinta-2); text-decoration: none; }
.rodape a:hover { color: var(--tinta); }
.rodape nav { display: flex; gap: 18px; flex-wrap: wrap; }

/* ---------- autenticação ---------- */
.auth { min-height: calc(100vh - 64px); display: grid; place-items: center; padding: 40px 16px; }
.auth .cartao { width: 100%; max-width: 440px; padding: 32px; }
.auth h1 { font-size: 1.9rem; margin-bottom: 6px; }
.auth .rodape-form { margin-top: 18px; font-size: .93rem; color: var(--tinta-2); text-align: center; }

/* ---------- painel do aluno ---------- */
.painel-cab { padding: 40px 0 8px; }
.progresso { height: 8px; border-radius: 999px; background: var(--papel-2); overflow: hidden; }
.progresso > span { display: block; height: 100%; border-radius: 999px; background: linear-gradient(90deg, var(--acento), color-mix(in srgb, var(--acento) 70%, var(--carga))); }
.curso-cartao { display: grid; grid-template-columns: 1fr auto; gap: 18px; align-items: center; }
.anel { --p: 0; width: 76px; height: 76px; border-radius: 50%; background: conic-gradient(var(--acento) calc(var(--p) * 1%), var(--papel-2) 0); display: grid; place-items: center; }
.anel span { width: 60px; height: 60px; border-radius: 50%; background: var(--cartao); display: grid; place-items: center; font: 600 .95rem var(--mono); }
.lista-aulas { list-style: none; padding: 0; margin: 0; display: grid; gap: 8px; }
.lista-aulas a { display: grid; grid-template-columns: 34px 1fr auto; gap: 14px; align-items: center; padding: 13px 16px; border: 1px solid var(--linha); border-radius: 12px; background: var(--cartao); text-decoration: none; color: var(--tinta); transition: border-color .15s, box-shadow .15s; }
.lista-aulas a:hover { border-color: var(--acento); box-shadow: var(--sombra); }
.estado { width: 30px; height: 30px; border-radius: 50%; display: grid; place-items: center; font: 600 .8rem var(--mono); background: var(--papel-2); color: var(--tinta-3); }
.estado.feito { background: var(--ok); color: #fff; }
.estado.andamento { background: var(--acento-bg); color: var(--acento-forte); }
.estado.bloqueado { background: var(--papel-2); }

/* ---------- aula ---------- */
.aula-layout { display: grid; grid-template-columns: 290px minmax(0, 1fr); gap: 40px; padding: 28px 0 60px; align-items: start; }
.aula-lateral { position: sticky; top: 84px; max-height: calc(100vh - 100px); overflow: auto; padding-right: 6px; }
.aula-lateral h2 { font: 600 .78rem var(--mono); text-transform: uppercase; letter-spacing: .08em; color: var(--tinta-3); margin: 0 0 12px; }
.aula-lateral ol { list-style: none; padding: 0; margin: 0; display: grid; gap: 2px; }
.aula-lateral a { display: grid; grid-template-columns: 26px 1fr; gap: 10px; align-items: center; padding: 8px 10px; border-radius: 9px; color: var(--tinta-2); text-decoration: none; font-size: .92rem; line-height: 1.3; }
.aula-lateral a:hover { background: var(--papel-2); color: var(--tinta); }
.aula-lateral a[aria-current="page"] { background: var(--acento-bg); color: var(--tinta); font-weight: 600; }
.aula-lateral .estado { width: 24px; height: 24px; font-size: .7rem; }
.aula-corpo { max-width: 820px; }
.aula-corpo > header { margin-bottom: 28px; }
.aula-corpo h2 { margin-top: 2.2rem; }
.aula-corpo h3 { margin-top: 1.6rem; }
.aula-corpo p, .aula-corpo li { color: var(--tinta); }
.aula-corpo ul, .aula-corpo ol { padding-left: 1.3em; }
.aula-corpo li { margin-bottom: .35em; }
.katex-display { overflow-x: auto; overflow-y: hidden; padding: 6px 0; }
.katex { font-size: 1.06em; }
.figura { margin: 24px 0; background: var(--cartao); border: 1px solid var(--linha); border-radius: var(--raio); padding: 16px; box-shadow: var(--sombra); }
.figura figcaption { font-size: .88rem; color: var(--tinta-3); margin-top: 8px; }
.destaque-box { border-left: 3px solid var(--acento); background: var(--acento-bg); padding: 14px 18px; border-radius: 0 12px 12px 0; margin: 20px 0; }
.destaque-box.atencao { border-color: var(--reacao); background: var(--reacao-bg); }
.destaque-box.norma { border-color: var(--carga); background: var(--carga-bg); }
.destaque-box > :last-child { margin-bottom: 0; }
.destaque-box b.titulo { display: block; font: 600 .78rem var(--mono); text-transform: uppercase; letter-spacing: .07em; margin-bottom: 6px; color: var(--tinta-2); }
.tabela { width: 100%; border-collapse: collapse; font-size: .95rem; margin: 18px 0; }
.tabela th, .tabela td { text-align: left; padding: 10px 12px; border-bottom: 1px solid var(--linha); vertical-align: top; }
.tabela th { font: 600 .78rem var(--mono); text-transform: uppercase; letter-spacing: .06em; color: var(--tinta-3); }
.tabela td.num, .tabela th.num { text-align: right; }
.rolagem { overflow-x: auto; }
.passos { counter-reset: passo; list-style: none; padding: 0 !important; display: grid; gap: 12px; }
.passos > li { counter-increment: passo; display: grid; grid-template-columns: 34px 1fr; gap: 12px; background: var(--cartao); border: 1px solid var(--linha); border-radius: 12px; padding: 14px 16px; }
.passos > li::before { content: counter(passo); width: 28px; height: 28px; border-radius: 50%; display: grid; place-items: center; font: 600 .82rem var(--mono); background: var(--acento-bg); color: var(--acento-forte); }
.aula-nav { display: flex; justify-content: space-between; gap: 12px; margin-top: 40px; padding-top: 24px; border-top: 1px solid var(--linha); flex-wrap: wrap; }
.video { position: relative; border-radius: var(--raio); overflow: hidden; background: #000; aspect-ratio: 16 / 9; box-shadow: var(--sombra-2); margin: 8px 0 28px; }
.video video { width: 100%; height: 100%; display: block; }
@media (max-width: 980px) { .aula-layout { grid-template-columns: 1fr; } .aula-lateral { position: static; max-height: none; } .aula-lateral ol { display: none; } .aula-lateral.aberta ol { display: grid; } }

/* ---------- simuladores ---------- */
.sim { margin: 28px 0; background: var(--cartao); border: 1px solid var(--linha); border-radius: var(--raio); box-shadow: var(--sombra); overflow: hidden; }
.sim-cab { display: flex; align-items: center; justify-content: space-between; gap: 12px; padding: 14px 18px; border-bottom: 1px solid var(--linha); background: var(--cartao-2); }
.sim-cab h3 { margin: 0; font-size: 1rem; }
.sim-cab .selo { flex: none; }
.sim-corpo { padding: 16px 18px 18px; display: grid; gap: 14px; }
.sim-palco { border: 1px solid var(--linha); border-radius: 11px; background: var(--papel); overflow: hidden; position: relative; }
.sim-palco svg { display: block; width: 100%; height: auto; }
.sim-palco.tres { height: 380px; cursor: grab; touch-action: none; }
.sim-palco canvas { display: block; }
.sim-dica { position: absolute; left: 10px; top: 8px; font: 500 .75rem var(--mono); color: var(--tinta-3); pointer-events: none; }
.abas { display: flex; flex-wrap: wrap; gap: 6px; }
.abas button, .chip { font: 500 .88rem var(--sans); color: var(--tinta-2); background: var(--papel); border: 1px solid var(--linha-2); border-radius: 9px; padding: 7px 12px; cursor: pointer; transition: all .15s; }
.abas button:hover, .chip:hover { border-color: var(--acento); color: var(--tinta); }
.abas button[aria-pressed="true"], .chip[aria-pressed="true"] { background: var(--acento-bg); border-color: var(--acento); color: var(--tinta); font-weight: 600; }
.controles { display: grid; gap: 10px; }
.controle { display: grid; grid-template-columns: minmax(120px, 190px) 1fr 86px; gap: 12px; align-items: center; font-size: .93rem; }
.controle label { color: var(--tinta-2); }
.controle output { font: 500 .92rem var(--mono); text-align: right; font-variant-numeric: tabular-nums; }
@media (max-width: 560px) { .controle { grid-template-columns: 1fr 80px; } .controle label { grid-column: 1 / -1; } }
.leituras { display: grid; grid-template-columns: repeat(auto-fit, minmax(140px, 1fr)); gap: 8px; }
.leitura { background: var(--papel); border: 1px solid var(--linha); border-radius: 10px; padding: 9px 12px; }
.leitura .k { font: 500 .74rem var(--mono); color: var(--tinta-3); }
.leitura .v { font: 600 1.02rem var(--mono); font-variant-numeric: tabular-nums; margin-top: 2px; }
.leitura .v.ok { color: var(--ok); } .leitura .v.erro { color: var(--erro); }
.sim-nota { font-size: .92rem; color: var(--tinta-2); margin: 0; }

/* ---------- exercícios ---------- */
.exercicio { margin: 28px 0; background: var(--cartao); border: 1px solid var(--linha); border-radius: var(--raio); box-shadow: var(--sombra); }
.exercicio > header { display: flex; justify-content: space-between; align-items: center; gap: 12px; padding: 14px 18px; border-bottom: 1px solid var(--linha); background: var(--cartao-2); border-radius: var(--raio) var(--raio) 0 0; }
.exercicio > header h3 { margin: 0; font-size: 1rem; }
.exercicio .corpo { padding: 18px; }
.respostas { display: grid; grid-template-columns: repeat(auto-fit, minmax(210px, 1fr)); gap: 12px; margin: 16px 0; }
.resposta { display: grid; gap: 6px; }
.resposta label { font-size: .9rem; font-weight: 600; }
.resposta .entrada { display: flex; align-items: stretch; }
.resposta input { border-radius: 10px 0 0 10px; font-family: var(--mono); }
.resposta .unid { display: grid; place-items: center; padding: 0 12px; border: 1px solid var(--linha-2); border-left: 0; border-radius: 0 10px 10px 0; background: var(--papel-2); color: var(--tinta-2); font: 500 .85rem var(--mono); white-space: nowrap; }
.resposta.certo input { border-color: var(--ok); background: color-mix(in srgb, var(--ok-bg) 60%, var(--cartao)); }
.resposta.errado input { border-color: var(--erro); background: color-mix(in srgb, var(--erro-bg) 60%, var(--cartao)); }
.resposta .marca { font-size: .82rem; font-weight: 600; min-height: 1.2em; }
.resposta.certo .marca { color: var(--ok); } .resposta.errado .marca { color: var(--erro); }
.exercicio .acoes { display: flex; gap: 10px; flex-wrap: wrap; align-items: center; }
.resolucao { margin-top: 18px; border-top: 1px dashed var(--linha-2); padding-top: 16px; }
.dica-sinal { font-size: .88rem; color: var(--tinta-3); }

/* ---------- desenhos do motor (desenho.js) ---------- */
.d-svg { display: block; width: 100%; height: auto; margin: 0 auto; font-family: var(--mono); overflow: visible; }
.d-barra { stroke: var(--tinta); stroke-width: 4.5; stroke-linecap: round; }
.d-trelica { stroke-width: 3; }
.d-destaque { stroke: var(--acento); }
.d-rotula { fill: var(--cartao); stroke: var(--tinta); stroke-width: 2.2; }
.d-apoio { fill: var(--apoio); stroke: var(--tinta-2); stroke-width: 1.5; stroke-linejoin: round; }
.d-apoio-pino, .d-apoio-roda { fill: var(--cartao); stroke: var(--tinta-2); stroke-width: 1.5; }
.d-solo-linha { stroke: var(--tinta-2); stroke-width: 2; }
.d-solo-hach { stroke: var(--tinta-3); stroke-width: 1.3; }
.d-solo { stroke: none; }
.d-carga, .d-carga-arco { stroke: var(--carga); stroke-width: 2; fill: none; }
.d-carga-p, .d-carga-arco-p { fill: var(--carga); }
.d-carga-borda { fill: none; stroke: var(--carga); stroke-width: 1.6; }
.d-reacao, .d-reacao-arco { stroke: var(--reacao); stroke-width: 2.4; fill: none; }
.d-reacao-p, .d-reacao-arco-p { fill: var(--reacao); }
.d-diag-pos { fill: color-mix(in srgb, var(--acento) 17%, transparent); }
.d-diag-neg { fill: color-mix(in srgb, var(--reacao) 17%, transparent); }
.d-diag-mix { fill: color-mix(in srgb, var(--acento) 12%, transparent); }
.d-diag-linha { fill: none; stroke: var(--acento); stroke-width: 2.2; stroke-linejoin: round; }
.d-hach { stroke: color-mix(in srgb, var(--acento) 40%, transparent); stroke-width: 1; }
.d-deformada { fill: none; stroke: var(--acento); stroke-width: 2.2; stroke-dasharray: 7 5; stroke-linecap: round; }
.d-cota, .d-cota-ext { stroke: var(--tinta-3); stroke-width: 1; }
.d-cota-tick { stroke: var(--tinta-2); stroke-width: 1.4; }
.d-secao { stroke: var(--reacao); stroke-width: 2; stroke-dasharray: 5 4; }
.d-txt { font: 500 12.5px var(--mono); fill: var(--tinta-2); }
.d-txt-carga { fill: var(--carga); font-weight: 600; }
.d-txt-reac { fill: var(--reacao); font-weight: 600; }
.d-txt-diag { fill: var(--acento-forte); font-weight: 600; paint-order: stroke; stroke: var(--cartao); stroke-width: 4px; stroke-linejoin: round; }
.d-txt-cota { fill: var(--tinta-3); }
.d-no { font: 600 14px var(--sans); fill: var(--tinta); }
.d-destaque-txt { fill: var(--acento); }
.sim-palco .d-txt-diag { stroke: var(--papel); }

/* ---------- certificado ---------- */
.cert-pagina { background: var(--papel-2); padding: 40px 16px; }
.certificado { max-width: 1000px; aspect-ratio: 297 / 210; margin: 0 auto; background: #FFFDF8; color: #1B1F27; border-radius: 6px; box-shadow: var(--sombra-2); position: relative; padding: 5.5% 7%; display: flex; flex-direction: column; justify-content: space-between; overflow: hidden; }
.certificado::before { content: ""; position: absolute; inset: 18px; border: 1.5px solid #CFC7B4; border-radius: 3px; pointer-events: none; }
.certificado::after { content: ""; position: absolute; inset: 24px; border: .5px solid #E3DCCB; pointer-events: none; }
.certificado .c-topo { display: flex; justify-content: space-between; align-items: center; font: 500 .8rem var(--mono); letter-spacing: .12em; text-transform: uppercase; color: #6B6556; }
.certificado h1 { font: 600 clamp(1.6rem, 4vw, 3rem) var(--serif); color: #1B1F27; text-align: center; margin: 0; letter-spacing: .02em; }
.certificado .c-texto { text-align: center; font: 400 clamp(.9rem, 1.7vw, 1.2rem)/1.7 var(--serif); color: #3B3F48; max-width: 76%; margin: 0 auto; }
.certificado .c-nome { font: 600 clamp(1.4rem, 3.4vw, 2.5rem)/1.2 var(--serif); color: #4336B8; font-style: italic; display: block; margin: .3em 0; }
.certificado .c-pe { display: grid; grid-template-columns: 1fr auto 1fr; align-items: end; gap: 20px; font: 400 .85rem var(--sans); color: #4B5263; }
.certificado .assinatura { border-top: 1px solid #8A8472; padding-top: 6px; text-align: center; }
.certificado .c-codigo { font: 500 .78rem var(--mono); text-align: right; }
.certificado .c-selo { width: 86px; height: 86px; }
@media print {
  @page { size: A4 landscape; margin: 0; }
  body { background: #fff; }
  .topo, .rodape, .nao-imprimir { display: none !important; }
  .cert-pagina { padding: 0; background: #fff; }
  .certificado { box-shadow: none; max-width: none; width: 297mm; height: 210mm; border-radius: 0; }
}

/* ---------- administração ---------- */
.adm-layout { display: grid; grid-template-columns: 220px minmax(0, 1fr); gap: 32px; padding: 28px 0 60px; }
.adm-menu { display: grid; gap: 2px; align-content: start; position: sticky; top: 84px; }
.adm-menu a { padding: 9px 12px; border-radius: 9px; color: var(--tinta-2); text-decoration: none; font-weight: 500; font-size: .94rem; }
.adm-menu a:hover { background: var(--papel-2); color: var(--tinta); }
.adm-menu a[aria-current="page"] { background: var(--acento-bg); color: var(--tinta); }
.metricas { display: grid; grid-template-columns: repeat(auto-fit, minmax(180px, 1fr)); gap: 14px; }
.metrica { background: var(--cartao); border: 1px solid var(--linha); border-radius: 12px; padding: 16px 18px; }
.metrica .k { font: 500 .76rem var(--mono); color: var(--tinta-3); text-transform: uppercase; letter-spacing: .06em; }
.metrica .v { font: 600 1.8rem/1.2 var(--serif); margin-top: 4px; }
@media (max-width: 860px) { .adm-layout { grid-template-columns: 1fr; } .adm-menu { position: static; grid-auto-flow: column; overflow-x: auto; } }

/* ---------- ajuda ---------- */
.ajuda-layout { display: grid; grid-template-columns: 260px minmax(0, 1fr); gap: 40px; padding: 32px 0 60px; }
.ajuda-indice { position: sticky; top: 84px; align-self: start; display: grid; gap: 2px; }
.ajuda-indice a { color: var(--tinta-2); text-decoration: none; padding: 6px 10px; border-radius: 8px; font-size: .93rem; }
.ajuda-indice a:hover { background: var(--papel-2); color: var(--tinta); }
.ajuda-secao { scroll-margin-top: 90px; padding-bottom: 12px; }
@media (max-width: 860px) { .ajuda-layout { grid-template-columns: 1fr; } .ajuda-indice { position: static; } }

@media (prefers-reduced-motion: reduce) { *, *::before, *::after { transition: none !important; animation: none !important; scroll-behavior: auto !important; } }
.d-tracao { stroke: var(--acento); }
.d-compressao { stroke: var(--reacao); }
.d-nula { stroke: var(--tinta-3); stroke-dasharray: 6 5; }
.d-txt-tracao { fill: var(--acento-forte); font-weight: 600; paint-order: stroke; stroke: var(--cartao); stroke-width: 4px; stroke-linejoin: round; }
.d-txt-compressao { fill: var(--reacao); font-weight: 600; paint-order: stroke; stroke: var(--cartao); stroke-width: 4px; stroke-linejoin: round; }

/* ícone do botão de tema: mostra a lua no claro e o sol no escuro */
.so-escuro { display: none; }
:root[data-tema="escuro"] .so-escuro { display: inline; } :root[data-tema="escuro"] .so-claro { display: none; }
@media (prefers-color-scheme: dark) { :root:not([data-tema="claro"]) .so-escuro { display: inline; } :root:not([data-tema="claro"]) .so-claro { display: none; } }
@media (max-width: 520px) { .so-largo { display: none; } }
.so-celular { display: none; }
@media (max-width: 980px) { .so-celular { display: flex; } }
/* grades com conteúdo largo (tabelas, figuras): a coluna pode encolher; o conteúdo rola por dentro */
.aula-layout > *, .adm-layout > *, .ajuda-layout > *, .grade > *, .heroi .conteiner > * { min-width: 0; }
@media (max-width: 980px) { .aula-layout { grid-template-columns: minmax(0, 1fr); } }
@media (max-width: 860px) { .adm-layout, .ajuda-layout { grid-template-columns: minmax(0, 1fr); } }