/* Fontes (auto-hospedadas, licença SIL OFL — ver fonts/) */
@font-face {
    font-family: 'Newsreader';
    font-style: normal;
    font-display: swap;
    font-weight: 200 800;
    src: url('fonts/newsreader-latin-wght-normal.woff2') format('woff2');
}

@font-face {
    font-family: 'Newsreader';
    font-style: italic;
    font-display: swap;
    font-weight: 200 800;
    src: url('fonts/newsreader-latin-wght-italic.woff2') format('woff2');
}

@font-face {
    font-family: 'IBM Plex Sans';
    font-style: normal;
    font-display: swap;
    font-weight: 100 700;
    src: url('fonts/ibm-plex-sans-latin-wght-normal.woff2') format('woff2');
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

/*
 * Paleta extraída da cianotipia "Dictyota dichotoma" (Anna Atkins, c. 1843).
 * Azul da Prússia do fundo da prancha e o branco papel das algas reveladas.
 */
:root {
    --ink: #173a55;          /* sombra mais profunda, rodapé */
    --deep: #1f4b6c;         /* áreas mais escuras da prancha */
    --plate: #275779;        /* azul da Prússia dominante do fundo */
    --plate-lift: #346386;   /* manchas mais claras ao redor do espécime */
    --wash: #7199af;         /* bordas translúcidas das algas */
    --mist: #a5c0cb;         /* véu claro das ramificações finas */
    --mist-hi: #bccfd7;      /* texto secundário sobre azul */
    --paper: #dcdad8;        /* branco papel do núcleo das algas */
    --paper-hi: #e9e7e2;     /* realces mais luminosos */

    --error-bg: #e8d3cb;
    --error-ink: #5c2015;

    --font-display: 'Newsreader', 'Iowan Old Style', 'Palatino Linotype', Georgia, serif;
    --font-body: 'IBM Plex Sans', 'Segoe UI', system-ui, -apple-system, sans-serif;

    --gutter: clamp(16px, 4vw, 32px);
    --section-space: clamp(4.5rem, 3rem + 6vw, 8rem);
    --header-height: 68px;
    --ease-out: cubic-bezier(0.16, 1, 0.3, 1);

    /* Grão de papel da cópia fotográfica */
    --grain: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='240' height='240'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.8' numOctaves='3' stitchTiles='stitch'/%3E%3CfeColorMatrix values='0 0 0 0 .86 0 0 0 0 .85 0 0 0 0 .84 .12 0 0 0 -.045'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
}

html {
    scroll-behavior: smooth;
    scroll-padding-top: var(--header-height);
    scrollbar-color: var(--wash) var(--deep);
    -webkit-text-size-adjust: 100%;
    text-size-adjust: 100%;
}

body {
    font-family: var(--font-body);
    font-size: 1.0625rem;
    line-height: 1.65;
    color: var(--paper);
    background-color: var(--ink);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

::selection {
    background-color: var(--paper-hi);
    color: var(--deep);
}

.paper ::selection {
    background-color: var(--plate);
    color: var(--paper-hi);
}

h1, h2, h3, h4 {
    font-family: var(--font-display);
    font-weight: 500;
    line-height: 1.12;
    letter-spacing: -0.01em;
    text-wrap: balance;
}

p {
    text-wrap: pretty;
}

:focus-visible {
    outline: 2px solid currentColor;
    outline-offset: 3px;
    border-radius: 2px;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--gutter);
}

.skip-link {
    position: absolute;
    left: var(--gutter);
    top: -100px;
    z-index: 200;
    padding: 10px 16px;
    background-color: var(--paper-hi);
    color: var(--deep);
    font-weight: 600;
    text-decoration: none;
    border-radius: 4px;
}

.skip-link:focus {
    top: 12px;
}

/* Superfícies: campo azul da prancha e papel */
.plate {
    background-color: var(--plate);
    background-image:
        var(--grain),
        radial-gradient(ellipse 55% 55% at 72% 45%, rgba(52, 99, 134, 0.6) 0%, transparent 70%);
    color: var(--paper);
}

.plate-deep {
    background-color: var(--deep);
    background-image:
        var(--grain),
        radial-gradient(ellipse 60% 70% at 50% 0%, var(--plate) 0%, transparent 75%);
}

.paper {
    background-color: var(--paper);
    color: var(--deep);
}

/* Header/Navigation */
.header {
    position: sticky;
    top: 0;
    z-index: 100;
    background-color: var(--deep);
    color: var(--paper-hi);
    border-bottom: 1px solid rgba(113, 153, 175, 0.35);
}

.header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 16px;
    min-height: var(--header-height);
}

.logo {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    color: var(--paper-hi);
    text-decoration: none;
    font-size: 0.9375rem;
    font-weight: 600;
    letter-spacing: 0.22em;
    text-transform: uppercase;
}

.logo-mark {
    width: 26px;
    height: 26px;
    flex: none;
}

.nav {
    display: flex;
    gap: clamp(16px, 3vw, 36px);
}

.nav-link {
    position: relative;
    color: var(--paper);
    text-decoration: none;
    font-size: 0.9375rem;
    font-weight: 500;
    padding: 6px 0;
    transition: color 0.2s ease;
}

.nav-link::after {
    content: '';
    position: absolute;
    left: 0;
    right: 0;
    bottom: 0;
    height: 1px;
    background-color: currentColor;
    transform: scaleX(0);
    transform-origin: left;
    transition: transform 0.35s var(--ease-out);
}

.nav-link:hover,
.nav-link[aria-current="true"] {
    color: var(--paper-hi);
}

.nav-link:hover::after,
.nav-link[aria-current="true"]::after {
    transform: scaleX(1);
}

/* Hero Section */
.hero {
    padding: clamp(3.5rem, 2rem + 6vw, 7rem) 0 clamp(3.5rem, 2rem + 5vw, 6rem);
    overflow: hidden;
}

.hero-grid {
    display: grid;
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 1fr);
    align-items: center;
    gap: clamp(2rem, 5vw, 5rem);
}

.hero-content h1 {
    font-size: clamp(2.5rem, 1.5rem + 3.6vw, 4.25rem);
    line-height: 1.04;
    letter-spacing: -0.02em;
    color: var(--paper-hi);
    margin-bottom: 1.5rem;
}

.hero-content p {
    font-size: clamp(1.0625rem, 1rem + 0.35vw, 1.25rem);
    line-height: 1.6;
    max-width: 34em;
    margin-bottom: 2.25rem;
}

.cta-button {
    display: inline-block;
    background-color: var(--paper-hi);
    color: var(--deep);
    padding: 15px 32px;
    text-decoration: none;
    border-radius: 4px;
    font-weight: 600;
    font-size: 1rem;
    box-shadow: 0 1px 2px rgba(23, 58, 85, 0.3);
    transition: transform 0.3s var(--ease-out), box-shadow 0.3s var(--ease-out), background-color 0.2s ease;
}

.cta-button:hover {
    background-color: #f3f1ec;
    transform: translateY(-2px);
    box-shadow: 0 10px 24px -8px rgba(15, 40, 60, 0.6);
}

.cta-button:active {
    transform: translateY(0);
    box-shadow: 0 1px 2px rgba(23, 58, 85, 0.3);
}

.cta-button:focus-visible {
    outline-color: var(--paper-hi);
}

/* Espécime: o grafo de Euler como fotograma de cianotipia */
.specimen {
    margin: 0;
    text-align: center;
}

.specimen-graph {
    display: block;
    width: 100%;
    max-width: 420px;
    height: auto;
    margin: 0 auto;
    overflow: visible;
}

.specimen-halo {
    fill: var(--wash);
    stroke: var(--mist);
    stroke-width: 12;
    stroke-linecap: round;
    opacity: 0.5;
    animation: breathe 6s ease-in-out infinite alternate;
}

.specimen-halo path {
    fill: none;
}

.specimen-edges {
    fill: none;
    stroke: var(--paper-hi);
    stroke-width: 2.25;
    stroke-linecap: round;
    transition: opacity 0.6s ease;
}

.specimen-edges path {
    stroke-dasharray: 1 1;
    stroke-dashoffset: 1;
    animation: expose 1.6s var(--ease-out) forwards;
    animation-delay: calc(250ms + var(--i) * 130ms);
}

.specimen-nodes {
    fill: var(--paper-hi);
}

.specimen-nodes circle,
.specimen-labels {
    opacity: 0;
    animation: develop 0.9s ease-out forwards 1.2s;
}

.specimen-labels {
    font-family: var(--font-display);
    font-style: italic;
    font-size: 14px;
    fill: var(--mist-hi);
    animation-delay: 1.6s;
}

.specimen-labels .node-label {
    font-size: 19px;
    fill: var(--paper-hi);
}

/*
 * Caminhada contínua (script.js): um ponto de luz tenta cruzar cada ponte
 * uma única vez. Sempre sobra uma, e ela pulsa antes do recomeço.
 */
.specimen-graph.is-walking .specimen-edges {
    opacity: 0.3;
}

.specimen-trace {
    fill: none;
    stroke: var(--paper-hi);
    stroke-width: 3;
    stroke-linecap: round;
    transition: opacity 0.9s ease;
}

.specimen-trace .is-unreachable {
    stroke: var(--mist);
    stroke-width: 2.25;
    animation: unreachable 0.9s ease-in-out infinite alternate;
}

.specimen-graph.is-resetting .specimen-trace {
    opacity: 0;
}

.specimen-walker {
    opacity: 0;
    transition: opacity 0.5s ease;
}

.specimen-graph.is-walking .specimen-walker {
    opacity: 1;
}

.walker-core {
    fill: var(--paper-hi);
}

.walker-glow {
    fill: var(--paper-hi);
    opacity: 0.65;
}

.walker-ripple {
    fill: none;
    stroke: var(--paper-hi);
    stroke-width: 1.5;
    opacity: 0;
    transform-box: fill-box;
    transform-origin: center;
}

.specimen-walker.is-stuck .walker-ripple {
    animation: ripple 1.4s ease-out infinite;
}

.specimen-labels text {
    transition: fill 0.4s ease;
}

.specimen-labels text.is-crossed {
    fill: var(--paper-hi);
}

.specimen-labels text.is-unreachable {
    animation: unreachable 0.9s ease-in-out infinite alternate;
}

.specimen figcaption {
    display: flex;
    flex-direction: column;
    align-items: center;
    margin-top: 0.75rem;
    font-family: var(--font-display);
    font-style: italic;
    font-size: 1.1875rem;
    line-height: 1.35;
    color: var(--paper);
}

.specimen figcaption span + span {
    font-size: 1rem;
    color: var(--mist-hi);
}

@keyframes expose {
    to { stroke-dashoffset: 0; }
}

@keyframes develop {
    to { opacity: 1; }
}

@keyframes breathe {
    to { opacity: 0.3; }
}

@keyframes unreachable {
    from { opacity: 1; }
    to { opacity: 0.2; }
}

@keyframes ripple {
    from { transform: scale(1); opacity: 0.8; }
    to { transform: scale(2.8); opacity: 0; }
}

/* Cabeçalhos de seção */
.sobre h2,
.servicos h2,
.diferenciais h2,
.contato h2 {
    font-size: clamp(2.125rem, 1.5rem + 2.2vw, 3.25rem);
    text-align: center;
    margin-bottom: clamp(2.5rem, 2rem + 2vw, 4rem);
}

/* Sobre Section */
.sobre {
    padding: var(--section-space) 0;
}

.sobre h2,
.sobre h3,
.sobre h4 {
    color: var(--plate);
}

.sobre-content {
    max-width: 960px;
    margin: 0 auto;
}

.sobre-content .lead {
    font-family: var(--font-display);
    font-size: clamp(1.25rem, 1.1rem + 0.6vw, 1.5rem);
    line-height: 1.5;
    color: var(--deep);
    max-width: 38em;
    margin: 0 auto;
}

.sobre h3 {
    font-size: clamp(1.5rem, 1.3rem + 0.8vw, 1.875rem);
    margin: clamp(3.5rem, 3rem + 2vw, 5rem) 0 1.75rem;
}

.sobre-content > p:last-child {
    max-width: 44em;
}

.expertise-grid {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 2.5rem;
}

.expertise-item {
    border-top: 1px solid var(--plate);
    padding-top: 1.25rem;
}

.expertise-item h4 {
    font-size: 1.3125rem;
    margin-bottom: 0.625rem;
}

.expertise-item p {
    font-size: 0.9875rem;
    line-height: 1.65;
}

/* Serviços Section */
.servicos {
    padding: var(--section-space) 0;
}

.servicos h2 {
    color: var(--paper-hi);
}

.servicos-grid {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    column-gap: clamp(2rem, 4vw, 3.5rem);
    row-gap: clamp(2.5rem, 4vw, 3.5rem);
}

.servico {
    border-top: 1px solid var(--wash);
    padding-top: 1.5rem;
}

.servico h3 {
    color: var(--paper-hi);
    font-size: 1.5rem;
    margin-bottom: 0.75rem;
}

.servico p {
    font-size: 0.9875rem;
    line-height: 1.7;
}

/* Diferenciais Section */
.diferenciais {
    padding: var(--section-space) 0;
}

.diferenciais h2,
.diferenciais h3 {
    color: var(--plate);
}

.diferenciais-grid {
    display: grid;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 2.5rem;
}

.diferencial {
    border-top: 1px solid var(--plate);
    padding-top: 1.25rem;
}

.diferencial h3 {
    font-size: 1.3125rem;
    margin-bottom: 0.625rem;
}

.diferencial p {
    font-size: 0.9875rem;
    line-height: 1.65;
}

/* Contato Section */
.contato {
    padding: var(--section-space) 0;
    text-align: center;
}

.contato h2 {
    color: var(--paper-hi);
    margin-bottom: 1.25rem;
}

.contato-intro {
    font-size: clamp(1.0625rem, 1rem + 0.35vw, 1.25rem);
    max-width: 34em;
    margin: 0 auto 3rem;
}

.contact-form {
    max-width: 560px;
    margin: 0 auto;
    text-align: left;
}

.form-group {
    margin-bottom: 1.25rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.375rem;
    font-size: 0.9375rem;
    font-weight: 500;
    color: var(--paper-hi);
}

.form-group .optional {
    font-weight: 400;
    color: var(--mist-hi);
}

.form-group input,
.form-group textarea {
    display: block;
    width: 100%;
    padding: 12px 14px;
    border: 1px solid transparent;
    border-radius: 4px;
    background-color: var(--paper);
    color: var(--ink);
    caret-color: var(--plate);
    font-family: inherit;
    font-size: 1rem;
    line-height: 1.5;
    transition: background-color 0.2s ease, box-shadow 0.2s ease;
}

.form-group textarea {
    resize: vertical;
    min-height: 132px;
}

.form-group input:hover,
.form-group textarea:hover {
    background-color: var(--paper-hi);
}

.form-group input:focus,
.form-group textarea:focus {
    outline: 2px solid var(--paper-hi);
    outline-offset: 2px;
    background-color: var(--paper-hi);
}

.form-group input:user-invalid,
.form-group textarea:user-invalid {
    border-color: var(--error-ink);
    box-shadow: 0 0 0 1px var(--error-ink);
}

.form-trap {
    position: absolute;
    left: -10000px;
    width: 1px;
    height: 1px;
    overflow: hidden;
}

.submit-button {
    width: 100%;
    margin-top: 0.5rem;
    padding: 15px;
    background-color: var(--paper-hi);
    color: var(--deep);
    border: none;
    border-radius: 4px;
    font-family: inherit;
    font-weight: 600;
    font-size: 1rem;
    cursor: pointer;
    box-shadow: 0 1px 2px rgba(15, 40, 60, 0.35);
    transition: transform 0.3s var(--ease-out), box-shadow 0.3s var(--ease-out), background-color 0.2s ease;
}

.submit-button:hover {
    background-color: #f3f1ec;
    transform: translateY(-2px);
    box-shadow: 0 10px 24px -8px rgba(10, 30, 46, 0.7);
}

.submit-button:active {
    transform: translateY(0);
}

.submit-button:focus-visible {
    outline-color: var(--paper-hi);
}

.submit-button:disabled {
    cursor: progress;
    background-color: var(--mist);
    transform: none;
    box-shadow: none;
}

.form-status {
    margin-top: 1rem;
    padding: 12px 16px;
    border-radius: 4px;
    font-size: 0.9375rem;
    background-color: var(--paper-hi);
    color: var(--deep);
}

.form-status[data-state="error"] {
    background-color: var(--error-bg);
    color: var(--error-ink);
}

.contact-info {
    margin-top: 3rem;
    font-size: 0.9375rem;
    color: var(--mist-hi);
}

.contact-info strong {
    color: var(--paper);
    font-weight: 600;
}

/* Footer */
.footer {
    background-color: var(--ink);
    color: var(--mist-hi);
    text-align: center;
    padding: 2.5rem 0;
    font-size: 0.875rem;
    border-top: 1px solid rgba(113, 153, 175, 0.25);
}

.footer p {
    margin: 4px 0;
}

.footer p + p {
    font-family: var(--font-display);
    font-style: italic;
    font-size: 1rem;
    color: var(--paper);
}

/* Página 404 */
.not-found {
    min-height: 100vh;
    min-height: 100svh;
    display: grid;
    place-items: center;
    text-align: center;
    padding: var(--gutter);
}

.not-found .logo-mark {
    width: 56px;
    height: 56px;
    color: var(--paper-hi);
    margin-bottom: 1.5rem;
}

.not-found h1 {
    font-size: clamp(2.25rem, 1.6rem + 2.5vw, 3.5rem);
    color: var(--paper-hi);
    margin-bottom: 1rem;
}

.not-found p {
    max-width: 30em;
    margin: 0 auto 2rem;
}

/* Responsivo */
@media (max-width: 960px) {
    .hero-grid {
        grid-template-columns: 1fr;
    }

    .specimen-graph {
        max-width: 340px;
    }

    .servicos-grid,
    .diferenciais-grid {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }
}

@media (max-width: 768px) {
    .expertise-grid {
        grid-template-columns: 1fr;
        gap: 2rem;
    }
}

@media (max-width: 600px) {
    :root {
        --header-height: 60px;
    }

    .logo {
        font-size: 0.8125rem;
        letter-spacing: 0.16em;
        gap: 8px;
    }

    .logo-mark {
        width: 22px;
        height: 22px;
    }

    .nav {
        gap: 14px;
    }

    .nav-link {
        font-size: 0.875rem;
    }

    .servicos-grid,
    .diferenciais-grid {
        grid-template-columns: 1fr;
        row-gap: 2.25rem;
    }

    .cta-button {
        display: block;
        text-align: center;
    }
}

@media (max-width: 380px) {
    .logo span {
        letter-spacing: 0.1em;
    }

    .nav {
        gap: 12px;
    }
}

@media (prefers-reduced-motion: reduce) {
    html {
        scroll-behavior: auto;
    }

    .specimen-edges path,
    .specimen-nodes circle,
    .specimen-labels {
        animation: none;
        stroke-dashoffset: 0;
        opacity: 1;
    }

    .specimen-halo {
        animation: none;
    }

    .cta-button,
    .submit-button,
    .nav-link::after {
        transition: none;
    }
}