/* base.css — reset, tipografia, foco e utilitarios. Nao declara cor literal. */

*, *::before, *::after { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: var(--font-sans);
  font-weight: 400;
  font-size: clamp(16px, 1.05vw, 18px);
  line-height: 1.55;
  background: var(--surface-base);
  color: var(--text-on-base);
  -webkit-font-smoothing: antialiased;
  transition: background-color .35s ease, color .35s ease;
}

img, svg { max-width: 100%; display: block; }

/* Controle de formulario nao herda font-family por padrao do navegador. */
button, input, select, textarea { font: inherit; color: inherit; }

a { color: var(--link); text-decoration: none; }
a:hover { text-decoration: underline; }

h1, h2, h3 {
  margin: 0;
  font-weight: 600;
  letter-spacing: -0.02em;
  line-height: 1.08;
}

h1 { font-size: clamp(2.4rem, 6vw, 4.4rem); letter-spacing: -0.025em; }
h2 { font-size: clamp(1.9rem, 4vw, 3.1rem); }
h3 { font-size: clamp(1.15rem, 1.7vw, 1.4rem); line-height: 1.2; }

p { margin: 0 0 1.1em; }

.rotulo {
  font-size: .72rem;
  font-weight: 600;
  letter-spacing: .15em;
  text-transform: uppercase;
  color: var(--accent-text);
  margin: 0 0 1.25rem;
}

.container {
  width: 100%;
  max-width: var(--maxw);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.secao { padding-block: clamp(72px, 10vw, 140px); position: relative; }

/* A faixa de onda inverte os papeis de texto dentro do proprio escopo. */
.contraste {
  background: var(--surface-contrast);
  color: var(--text-on-contrast);
}
.contraste .rotulo { color: var(--accent-on-contrast); }
.contraste .texto-suave { color: var(--text-muted-on-contrast); }

.texto-suave { color: var(--text-muted-on-base); }

/* Foco visivel nas duas superficies: dois aneis, um claro e um escuro. */
:focus-visible {
  outline: 3px solid var(--foco-cor);
  outline-offset: 3px;
  box-shadow: 0 0 0 6px var(--foco-halo);
  border-radius: var(--radius);
}

.pular-para-conteudo {
  position: absolute;
  left: -9999px;
}
.pular-para-conteudo:focus {
  left: var(--gutter);
  top: 12px;
  z-index: 100;
  padding: .7rem 1rem;
  background: var(--ambar);
  color: var(--marinho);
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: .001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .001ms !important;
  }
}