/* Prof. Victor Hugo — portal do Laboratório de Álgebra
   Direção visual: docs/DIRECAO_VISUAL.md */
:root {
  --deep: #0c2f3a; --deep-2: #12404d; --on-deep: #eaf4f3; --on-deep-muted: #a9c6c6;
  --paper: #f6f8f7; --panel: #ffffff; --ink: #13232a; --muted: #50636b; --line: #d5e0e0; --grid: #e4ecec;
  --teal: #086d66; --teal-ink: #ffffff; --teal-soft: #ddf0ed;
  --amber: #8f5a00; --amber-hi: #f2b84b; --amber-soft: #fbefd2;
  --slate: #3f5675; --slate-soft: #e7ecf3;
  --f-display: "Young Serif", Georgia, "Times New Roman", serif;
  --f-body: "Atkinson Hyperlegible", "Segoe UI", system-ui, sans-serif;
  --f-mono: "JetBrains Mono", ui-monospace, Consolas, monospace;
  --head-h: 64px;
  --ease: cubic-bezier(.2, .7, .2, 1);
  --t-fast: 160ms; --t-mid: 320ms;
  color-scheme: light;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --deep: #08202a; --deep-2: #0f3340; --paper: #0e171a; --panel: #142024; --ink: #e5eded; --muted: #9fb3b7; --line: #263a3f; --grid: #182629;
    --teal: #4fd1c1; --teal-ink: #062824; --teal-soft: #15332f; --amber: #f2b84b; --amber-soft: #36290f; --slate: #aabdd8; --slate-soft: #1c2735;
    color-scheme: dark;
  }
}
:root[data-theme="dark"] {
  --deep: #08202a; --deep-2: #0f3340; --paper: #0e171a; --panel: #142024; --ink: #e5eded; --muted: #9fb3b7; --line: #263a3f; --grid: #182629;
  --teal: #4fd1c1; --teal-ink: #062824; --teal-soft: #15332f; --amber: #f2b84b; --amber-soft: #36290f; --slate: #aabdd8; --slate-soft: #1c2735;
  color-scheme: dark;
}

*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body { margin: 0; background: var(--paper); color: var(--ink); font-family: var(--f-body); font-size: 17px; line-height: 1.6; overflow-wrap: break-word; }
[id] { scroll-margin-top: calc(var(--head-h) + 16px); }
#conteudo { scroll-margin-top: 0; }
#conteudo:focus { outline: none; }
a { color: var(--teal); text-underline-offset: 3px; }
h1, h2, h3 { text-wrap: balance; }
p { text-wrap: pretty; }
:focus-visible { outline: 3px solid var(--amber-hi); outline-offset: 3px; border-radius: 6px; }
.wrap { max-width: 1120px; margin: 0 auto; padding-inline: 20px; }
.sr-only { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; }
.skip { position: absolute; left: 12px; top: -60px; z-index: 50; background: var(--panel); color: var(--ink); padding: 10px 14px; border-radius: 8px; font-weight: 700; transition: top var(--t-fast); }
.skip:focus { top: 12px; }
.eyebrow { font-family: var(--f-mono); font-size: 12.5px; letter-spacing: .12em; text-transform: uppercase; color: var(--teal); margin: 0 0 12px; }

/* botões */
.btn { --bg: transparent; --fg: var(--teal); --bd: var(--teal);
  display: inline-flex; align-items: center; justify-content: center; gap: 10px; min-height: 46px; padding: 10px 18px;
  font: 700 16px/1.2 var(--f-body); text-decoration: none; text-align: center; border-radius: 10px; border: 1.5px solid var(--bd);
  background: var(--bg); color: var(--fg); cursor: pointer; touch-action: manipulation;
  transition: transform var(--t-fast) var(--ease), background-color var(--t-fast), box-shadow var(--t-fast); }
.btn.primary { --bg: var(--teal); --fg: var(--teal-ink); }
.btn.ghost { --bd: var(--line); --fg: var(--ink); }
.btn:hover { box-shadow: 0 6px 18px -8px color-mix(in srgb, var(--teal) 70%, transparent); transform: translateY(-1px); }
.btn:active { transform: translateY(1px) scale(.98); box-shadow: none; }
.btn.small { min-height: 42px; font-size: 15px; padding: 8px 14px; }
.btn[disabled] { opacity: .5; cursor: default; transform: none; box-shadow: none; }
.btn .tag { font: 600 12px var(--f-mono); padding: 3px 7px; border-radius: 6px; background: var(--teal-soft); color: var(--teal); }

/* cabeçalho */
.top { position: sticky; top: 0; z-index: 20; background: color-mix(in srgb, var(--deep) 94%, transparent); color: var(--on-deep); border-bottom: 1px solid rgb(255 255 255 / .08); backdrop-filter: blur(8px); }
.top-in { display: flex; align-items: center; justify-content: space-between; gap: 16px; min-height: var(--head-h); }
.mark { display: inline-flex; align-items: center; gap: 10px; color: inherit; text-decoration: none; font-family: var(--f-display); font-size: 19px; }
.mark svg { width: 30px; height: 30px; flex: none; }
.mk-bg { fill: #4fd1c1; }
.mk-eq { stroke: var(--deep); stroke-width: 3; stroke-linecap: round; }
#nav { display: flex; align-items: center; gap: 4px; }
#nav a { color: var(--on-deep-muted); text-decoration: none; font-size: 15.5px; padding: 10px 12px; border-radius: 8px; position: relative; transition: color var(--t-fast); }
#nav a::after { content: ""; position: absolute; left: 12px; right: 12px; bottom: 5px; height: 2px; background: #4fd1c1; transform: scaleX(0); transform-origin: left; transition: transform var(--t-mid) var(--ease); }
#nav a:hover, #nav a[aria-current="true"] { color: #fff; }
#nav a[aria-current="true"]::after, #nav a:hover::after { transform: scaleX(1); }
.theme { margin-left: 6px; width: 44px; height: 44px; display: grid; place-items: center; border-radius: 10px; border: 1px solid rgb(255 255 255 / .18); background: transparent; color: var(--on-deep); cursor: pointer; transition: transform var(--t-mid) var(--ease); }
.theme svg { width: 20px; height: 20px; }
.theme-lbl { display: none; }
.theme:active { transform: rotate(180deg); }
.menu-btn { display: none; }
@media (max-width: 760px) {
  .js .menu-btn:not([hidden]) { display: inline-flex; align-items: center; gap: 10px; min-height: 44px; padding: 8px 12px; border-radius: 10px; border: 1px solid rgb(255 255 255 / .2); background: transparent; color: var(--on-deep); font: 700 15px var(--f-body); cursor: pointer; }
  .bars, .bars::before, .bars::after { display: block; width: 18px; height: 2px; background: currentColor; border-radius: 2px; transition: transform var(--t-mid) var(--ease), opacity var(--t-fast); }
  .bars { position: relative; }
  .bars::before, .bars::after { content: ""; position: absolute; left: 0; }
  .bars::before { top: -6px; } .bars::after { top: 6px; }
  .menu-btn[aria-expanded="true"] .bars { background: transparent; }
  .menu-btn[aria-expanded="true"] .bars::before { transform: translateY(6px) rotate(45deg); }
  .menu-btn[aria-expanded="true"] .bars::after { transform: translateY(-6px) rotate(-45deg); }
  .top-in { flex-wrap: wrap; }
  #nav { width: 100%; flex-wrap: wrap; padding-bottom: 10px; }
  .js #nav { position: absolute; left: 0; right: 0; top: 100%; flex-direction: column; align-items: stretch; gap: 2px; padding: 8px 16px 16px; background: var(--deep); border-bottom: 1px solid rgb(255 255 255 / .1);
    opacity: 0; transform: translateY(-8px); visibility: hidden; transition: opacity var(--t-mid) var(--ease), transform var(--t-mid) var(--ease), visibility 0s linear var(--t-mid); }
  .js #nav.open { opacity: 1; transform: none; visibility: visible; transition-delay: 0s; }
  .js #nav a { font-size: 18px; padding: 12px; }
  .js #nav a::after { display: none; }
  .js #nav a[aria-current="true"] { background: rgb(255 255 255 / .07); }
  .js .theme { margin: 6px 0 0; width: auto; display: flex; gap: 10px; justify-content: start; padding: 0 12px; font: 16px var(--f-body); }
  .js .theme-lbl { display: inline; }
}

/* abertura */
.hero { position: relative; overflow: hidden; background: var(--deep); color: var(--on-deep);
  background-image: linear-gradient(rgb(255 255 255 / .045) 1px, transparent 1px), linear-gradient(90deg, rgb(255 255 255 / .045) 1px, transparent 1px);
  background-size: 30px 30px; }
.axes { position: absolute; inset: 0; width: 100%; height: 100%; pointer-events: none; }
.axes path { fill: none; stroke: rgb(255 255 255 / .16); stroke-width: 1.5; }
.axes .line { stroke: rgb(79 209 193 / .28); stroke-width: 2; stroke-dasharray: 8 8; }
.hero-in { position: relative; display: grid; grid-template-columns: minmax(0, 1.1fr) minmax(0, 1fr); gap: 56px; align-items: center; padding-block: 88px 96px; }
.hero .eyebrow { color: #4fd1c1; }
.hero h1 { font-family: var(--f-display); font-weight: 400; font-size: clamp(44px, 7.4vw, 84px); line-height: 1; margin: 0; letter-spacing: -.01em; }
.fullname { margin: 14px 0 0; color: var(--on-deep-muted); font-size: 16px; }
.lead { margin: 24px 0 0; font-size: clamp(18px, 2.1vw, 21px); max-width: 30em; }
.cta { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 32px; }
.hero .btn.primary { --bg: #4fd1c1; --fg: #062824; --bd: #4fd1c1; }
.hero .btn.line { --fg: var(--on-deep); --bd: rgb(255 255 255 / .35); }
@media (max-width: 880px) { .hero-in { grid-template-columns: minmax(0, 1fr); gap: 40px; padding-block: 52px 60px; } }

/* quadro da equação */
.board { margin: 0; background: var(--panel); color: var(--ink); border-radius: 18px; padding: 24px 24px 20px; box-shadow: 0 30px 60px -30px rgb(0 0 0 / .55), 0 0 0 1px rgb(255 255 255 / .06); }
.board-cap { display: flex; justify-content: space-between; gap: 8px; flex-wrap: wrap; font: 600 11.5px var(--f-mono); letter-spacing: .1em; text-transform: uppercase; color: var(--muted); margin-bottom: 16px; }
.board-cap .lvl { color: var(--amber); }
.solution { list-style: none; margin: 0; padding: 0; font-family: var(--f-mono); font-variant-numeric: tabular-nums; }
.solution li { display: grid; grid-template-columns: minmax(0, 1fr) 2.2ch minmax(0, 1fr); align-items: baseline; column-gap: 10px; }
.solution .row { font-size: clamp(26px, 4vw, 36px); line-height: 1.35; }
.solution .l { text-align: right; } .solution .eq { text-align: center; color: var(--muted); }
.solution .op { font-size: 15px; color: var(--amber); padding: 2px 0 6px; }
.solution .op b { font-weight: 600; background: var(--amber-soft); padding: 2px 8px; border-radius: 6px; display: inline-block; }
.solution .op .why { grid-column: 1 / -1; text-align: center; font-size: 12.5px; color: var(--muted); }
.solution .final { color: var(--teal); font-weight: 600; }
.solution .check { display: block; text-align: center; font-size: 14px; color: var(--muted); margin-top: 12px; padding-top: 12px; border-top: 1px dashed var(--line); }
.board-ctrl { display: none; gap: 10px; flex-wrap: wrap; margin-top: 18px; }
.js .board-ctrl { display: flex; }
/* passos (só com JS: sem JS, toda a resolução aparece) */
.js .solution [data-step] { transition: opacity var(--t-mid) var(--ease), transform var(--t-mid) var(--ease); }
.js .solution.stepping [data-step].ahead { opacity: 0; visibility: hidden; transform: translateY(6px); }
.js .solution [data-step] { transition-property: opacity, transform, visibility; }
.js .solution.stepping .op.ahead b { transform: scale(.6); }
.js .solution .op b { transition: transform var(--t-mid) var(--ease); }
.js .solution .row.now { animation: pulse 700ms var(--ease); }
@keyframes pulse { 40% { transform: scale(1.04); } }

/* entrada inicial */
.js .hero .intro > *, .js .board { animation: rise 640ms var(--ease) both; }
.js .hero .intro > :nth-child(2) { animation-delay: 60ms; }
.js .hero .intro > :nth-child(3) { animation-delay: 110ms; }
.js .hero .intro > :nth-child(4) { animation-delay: 160ms; }
.js .hero .intro > :nth-child(5) { animation-delay: 210ms; }
.js .board { animation-delay: 240ms; }
@keyframes rise { from { opacity: 0; transform: translateY(18px); } }

/* seções */
.block { padding-block: 96px; }
.block h2 { font-family: var(--f-display); font-weight: 400; font-size: clamp(32px, 4.6vw, 48px); line-height: 1.1; margin: 0 0 16px; }
.sub { color: var(--muted); max-width: 40em; margin: 0; font-size: 18px; }
@media (max-width: 700px) { .block { padding-block: 64px; } }

.about-in { display: grid; grid-template-columns: minmax(0, 1.2fr) minmax(0, 1fr); gap: 64px; align-items: start; }
.about-in p { max-width: 34em; margin: 0 0 14px; }
.roles { list-style: none; margin: 0; padding: 0; border-top: 2px solid var(--ink); }
.roles li { display: grid; grid-template-columns: 52px minmax(0, 1fr); gap: 12px; padding: 18px 0; border-bottom: 1px solid var(--line); }
.roles .n { font: 600 14px var(--f-mono); color: var(--amber); padding-top: 3px; }
.roles h3 { margin: 0; font-size: 18px; }
.roles p { margin: 2px 0 0; color: var(--muted); font-size: 15.5px; }
@media (max-width: 820px) { .about-in { grid-template-columns: minmax(0, 1fr); gap: 32px; } }

/* laboratório */
.lab { background: var(--panel); border-block: 1px solid var(--line); }
.lab-head { display: grid; grid-template-columns: minmax(0, 1.2fr) minmax(0, 1fr); gap: 48px; align-items: end; margin-bottom: 56px; }
.levels { list-style: none; margin: 0; padding: 0; display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); border: 1px solid var(--line); border-radius: 14px; overflow: hidden; }
.levels li { padding: 14px; border-right: 1px solid var(--line); background: var(--paper); }
.levels li:last-child { border-right: 0; }
.levels b { display: block; font-size: 15px; }
.levels span { font: 13px var(--f-mono); color: var(--muted); }
.levels i { display: block; height: 6px; margin-top: 10px; border-radius: 3px; width: calc(var(--n) * 33.33%); background: var(--teal); }
.note { font-size: 14.5px; color: var(--muted); margin: 10px 0 0; }
@media (max-width: 820px) { .lab-head { grid-template-columns: minmax(0, 1fr); gap: 24px; } }
@media (max-width: 400px) { .levels li { padding: 12px 10px; } .levels b { font-size: 14px; } }

.projects { display: grid; gap: 28px; }
.proj { display: grid; grid-template-columns: minmax(0, .9fr) minmax(0, 1.1fr); gap: 48px; align-items: start; padding: 40px 0; border-top: 1px solid var(--line); }
.proj.flip .art { order: 2; }
.proj h3 { font-family: var(--f-display); font-weight: 400; font-size: clamp(26px, 3.2vw, 34px); line-height: 1.15; margin: 0; }
.proj .head { display: flex; flex-wrap: wrap; align-items: center; gap: 10px 14px; }
.proj .body > p { margin: 12px 0 0; max-width: 38em; }
.proj .meta { font: 13px var(--f-mono); color: var(--muted); }
.status { font: 600 12px var(--f-mono); letter-spacing: .03em; border-radius: 99px; padding: 5px 11px; white-space: nowrap; }
.status.ready { background: var(--teal-soft); color: var(--teal); }
.status.dev { background: var(--amber-soft); color: var(--amber); }
.sample { font: 15px var(--f-mono); background: var(--paper); border-left: 3px solid var(--amber); border-radius: 0 8px 8px 0; padding: 10px 14px; overflow-x: auto; }
.actions { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 20px; }
@media (max-width: 820px) { .proj { grid-template-columns: minmax(0, 1fr); gap: 20px; padding: 32px 0; } .proj.flip .art { order: 0; } }

/* ilustrações */
.art { background: var(--paper); border: 1px solid var(--line); border-radius: 18px; aspect-ratio: 16 / 10; display: grid; place-items: center; padding: 12px;
  background-image: linear-gradient(var(--grid) 1px, transparent 1px), linear-gradient(90deg, var(--grid) 1px, transparent 1px); background-size: 20px 20px; }
.art svg { width: 100%; height: 100%; overflow: visible; }
.art text { font: 600 15px var(--f-mono); text-anchor: middle; fill: var(--ink); }
.tile rect { fill: var(--panel); stroke: var(--ink); stroke-width: 2; }
.tile line { stroke: var(--line); stroke-width: 2; }
.tile .num { fill: var(--teal); font-size: 22px; }
.link { fill: none; stroke: var(--amber); stroke-width: 2.5; stroke-dasharray: 5 5; }
.card rect { fill: var(--panel); stroke: var(--ink); stroke-width: 2; }
.card text { font-size: 17px; }
.chip circle { fill: var(--panel); stroke: var(--line); stroke-width: 2; }
.chip.hit circle { fill: var(--teal-soft); stroke: var(--teal); }
.chip.hit text { fill: var(--teal); }
.post, .beam line { stroke: var(--ink); stroke-width: 3; fill: none; stroke-linecap: round; }
.tri { fill: var(--amber); }
.pan { fill: var(--teal-soft); stroke: var(--teal); stroke-width: 2; }
.grid path { stroke: var(--line); stroke-width: 1.5; }
.route { fill: none; stroke: var(--teal); stroke-width: 3; stroke-dasharray: 6 6; }
.station circle { fill: var(--amber-soft); stroke: var(--amber); stroke-width: 2; }
.station text { font-size: 12px; fill: var(--amber); }
.bulb circle { fill: var(--amber-hi); }
.bulb text { font-size: 10.5px; fill: #3a2600; }
.bot { fill: var(--ink); }

/* revelação única das ilustrações */
.js .reveal .t2, .js .reveal .k2, .js .reveal .beam, .js .reveal .bot, .js .reveal .link { transition: transform 700ms var(--ease), opacity 500ms; }
.js .reveal:not(.seen) .t2 { transform: translateX(40px); opacity: 0; }
.js .reveal:not(.seen) .link { opacity: 0; }
.js .reveal:not(.seen) .k2 { transform: translateY(18px); }
.beam { transform-origin: 160px 70px; }
.js .reveal:not(.seen) .beam { transform: rotate(-7deg); }
.js .reveal.seen .bot { transform: translate(176px, -100px); transition-duration: 1400ms; transition-delay: 200ms; }

/* listas de materiais */
.files { margin-top: 24px; border: 1px solid var(--line); border-radius: 14px; background: var(--paper); }
.files summary { list-style: none; display: flex; justify-content: space-between; align-items: center; gap: 12px; padding: 14px 18px; min-height: 52px; cursor: pointer; font-weight: 700; color: var(--teal); border-radius: 14px; }
.files summary::-webkit-details-marker { display: none; }
.files summary::after { content: ""; width: 10px; height: 10px; border-right: 2px solid currentColor; border-bottom: 2px solid currentColor; transform: rotate(45deg); transition: transform var(--t-mid) var(--ease); margin-left: 4px; flex: none; }
.files[open] summary::after { transform: rotate(-135deg); }
.files summary span:first-child { margin-right: auto; }
.files .count { font: 12.5px var(--f-mono); color: var(--muted); }
.files ul { list-style: none; margin: 0; padding: 0 18px; border-top: 1px solid var(--line); }
.files[open] ul { animation: drop var(--t-mid) var(--ease); }
@keyframes drop { from { opacity: 0; transform: translateY(-6px); } }
.files li { display: grid; grid-template-columns: minmax(0, 1fr) auto; gap: 12px; align-items: center; padding: 12px 0; border-bottom: 1px solid var(--line); }
.files li:last-child { border-bottom: 0; }
.files li a { font-weight: 700; text-decoration: none; min-height: 44px; display: flex; flex-direction: column; justify-content: center; }
.files li a:hover { text-decoration: underline; }
.files small { font-weight: 400; color: var(--muted); font-size: 14px; }
.files .sz { font: 12.5px var(--f-mono); color: var(--muted); white-space: nowrap; }
.files .note { padding: 0 18px 16px; }

/* contato */
.contact-in { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1.1fr); gap: 48px; align-items: center; }
.mailbox { background: var(--deep); color: var(--on-deep); border-radius: 18px; padding: 28px; }
.addr { font: 600 clamp(15px, 2.3vw, 22px) var(--f-mono); margin: 0 0 20px; overflow-wrap: anywhere; user-select: all; }
.mail-actions { display: flex; flex-wrap: wrap; gap: 12px; }
.mailbox .btn.primary { --bg: #4fd1c1; --fg: #062824; --bd: #4fd1c1; }
.mailbox .btn.line { --fg: var(--on-deep); --bd: rgb(255 255 255 / .35); }
.mailbox .btn.ok { --bd: #4fd1c1; --fg: #4fd1c1; }
.copy-status { min-height: 1.5em; margin: 12px 0 0; font-size: 15px; color: var(--on-deep-muted); }
@media (max-width: 820px) { .contact-in { grid-template-columns: minmax(0, 1fr); gap: 24px; } }

.foot { background: var(--deep); color: var(--on-deep-muted); font-size: 14.5px; padding-block: 28px 40px; }
.foot-in { display: flex; justify-content: space-between; gap: 12px 24px; flex-wrap: wrap; }
.foot-eq { font-family: var(--f-mono); color: #4fd1c1; }

/* 404 */
.nf { min-height: 70vh; display: grid; place-items: center; text-align: center; padding-block: 64px; }
.nf h1 { font-family: var(--f-display); font-weight: 400; font-size: clamp(36px, 6vw, 56px); margin: 0 0 12px; }
.nf .eqn { font: 600 clamp(22px, 4vw, 32px) var(--f-mono); color: var(--amber); margin: 0 0 16px; }
.nf .cta { justify-content: center; }

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation: none !important; transition-duration: 0s !important; transition-delay: 0s !important; }
  .js .reveal:not(.seen) .t2, .js .reveal:not(.seen) .k2, .js .reveal:not(.seen) .beam { transform: none; opacity: 1; }
  .js .reveal:not(.seen) .link { opacity: 1; }
  .js .reveal .bot { transform: translate(176px, -100px); }
}