:root {
  --bg: #f5f5f5;
  --bg-card: #ffffff;
  --primary: #006699;
  --primary-dark: #004766;
  --accent: #ff9800;
  --text: #222222;
  --muted: #666666;
  --border: #dddddd;
  --code-bg: #272822;
  --code-text: #f8f8f2;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  background-color: var(--bg);
  color: var(--text);
  line-height: 1.6;
}

header {
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  color: #ffffff;
  padding: 1.5rem 1rem;
}

header .container {
  max-width: 960px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

header h1 {
  margin: 0;
  font-size: 1.8rem;
}

header p {
  margin: 0;
  max-width: 640px;
  font-size: 0.95rem;
}

.tag {
  display: inline-block;
  padding: 0.1rem 0.5rem;
  border-radius: 999px;
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  background-color: #e3f2fd;
  color: var(--primary-dark);
  margin-right: 0.4rem;
}

.tag--aulas {
  background-color: #e8f5e9;
  color: #1b5e20;
}

.tag--nivel {
  background-color: #fff3e0;
  color: #e65100;
}

nav {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  font-size: 0.9rem;
}

nav a {
  color: #ffffff;
  text-decoration: none;
  padding: 0.25rem 0.6rem;
  border-radius: 999px;
  border: 1px solid rgba(255, 255, 255, 0.4);
}

nav a:hover {
  background-color: rgba(255, 255, 255, 0.16);
}

main {
  max-width: 960px;
  margin: 1.5rem auto 2.5rem;
  padding: 0 1rem;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1.5rem;
}

@media (min-width: 900px) {
  main {
    grid-template-columns: minmax(0, 2fr) minmax(260px, 0.9fr);
    align-items: flex-start;
  }
}

.card {
  background-color: var(--bg-card);
  border-radius: 0.5rem;
  padding: 1.25rem 1.5rem;
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.05);
  border: 1px solid var(--border);
  margin-bottom: 1.5rem;
}

.card h2 {
  border-bottom: 1px solid var(--border);
  padding-bottom: 0.4rem;
  margin-bottom: 0.8rem;
  color: var(--primary);
}

.card h3 {
  margin-top: 1.2rem;
  font-size: 1.2rem;
  color: var(--primary-dark);
}

code {
  font-family: "Fira Code", "SF Mono", "Consolas", "Roboto Mono", monospace;
  background-color: #ececec;
  padding: 0.1rem 0.25rem;
  border-radius: 3px;
  font-size: 0.9em;
}

pre {
  background-color: var(--code-bg);
  color: var(--code-text);
  padding: 1rem;
  border-radius: 0.4rem;
  overflow-x: auto;
  font-size: 0.9rem;
  margin: 0.5rem 0 1rem;
  line-height: 1.4;
  border: 1px solid #333;
}

pre code {
  background-color: transparent;
  padding: 0;
  color: inherit;
  display: block;
}

.note {
  border-left: 4px solid var(--primary);
  padding-left: 0.75rem;
  margin: 0.8rem 0;
  color: var(--muted);
  font-size: 0.95rem;
  font-style: italic;
}

.callout {
  border-radius: 0.4rem;
  padding: 1rem;
  background-color: #fff8e1;
  border: 1px solid #ffe082;
  font-size: 0.95rem;
  margin: 1rem 0;
}

.callout strong {
  color: #e65100;
}

footer {
  border-top: 1px solid var(--border);
  margin-top: 2rem;
  padding-top: 1rem;
  font-size: 0.85rem;
  color: var(--muted);
  text-align: center;
}

aside {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.pill-list {
  list-style: none;
  padding: 0;
  margin: 0.5rem 0 1rem;
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.pill-list li {
  background-color: #e0f7fa;
  color: #006064;
  border-radius: 999px;
  padding: 0.2rem 0.8rem;
  font-size: 0.85rem;
  font-weight: 500;
}

.step {
  margin-bottom: 1.5rem;
}

.example-box {
  background: #f8f9fa;
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: 1rem;
  margin: 0.5rem 0;
}

details {
  margin: 0.4rem 0 0.7rem;
  border-radius: 0.4rem;
  border: 1px solid var(--border);
  background-color: #fafafa;
}

details summary {
  padding: 0.5rem 0.7rem;
  cursor: pointer;
  font-weight: 600;
}

details[open] summary {
  border-bottom: 1px solid var(--border);
}

details > div {
  padding: 0.6rem 0.8rem 0.7rem;
}

.mini-list {
  list-style: none;
  padding: 0;
  margin: 0.5rem 0;
  font-size: 0.9rem;
}

.mini-list li {
  margin-bottom: 0.4rem;
}

.preview-frame {
  border: 2px dashed var(--border);
  padding: 1.5rem;
  background: #fff;
  border-radius: 8px;
  margin-top: 1rem;
}

.preview-header {
  background: #eee;
  padding: 0.5rem;
  font-size: 0.8rem;
  border-bottom: 1px solid var(--border);
  margin: -1.5rem -1.5rem 1rem -1.5rem;
  border-radius: 6px 6px 0 0;
  color: var(--muted);
}

.preview-form label {
  display: block;
  margin-top: 10px;
  font-weight: bold;
  font-size: 0.9rem;
}

.preview-form input {
  width: 100%;
  padding: 8px;
  margin-top: 4px;
  border: 1px solid #ccc;
  border-radius: 4px;
}

.preview-form button {
  margin-top: 15px;
  padding: 10px 20px;
  background: var(--primary);
  color: #fff;
  border: none;
  border-radius: 4px;
  cursor: pointer;
}

/* Estilos específicos dos exemplos DOM da própria página */
.dom-destaque {
  background-color: #e3f2fd;
  border-left: 4px solid var(--primary);
  padding: 0.5rem 0.75rem;
  border-radius: 4px;
}

.dom-card {
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 0.75rem;
  margin-top: 0.5rem;
}

.contador {
  font-size: 1.8rem;
  font-weight: bold;
  color: var(--primary-dark);
}

.btn {
  padding: 0.35rem 0.8rem;
  border-radius: 999px;
  border: none;
  cursor: pointer;
  background-color: var(--primary);
  color: #fff;
  font-size: 0.9rem;
}

.btn:hover {
  background-color: var(--primary-dark);
}

.btn-secundario {
  background-color: var(--accent);
  color: #222;
}

.lista-dinamica li {
  padding: 0.2rem 0;
}

.erro {
  color: #c62828;
  font-weight: bold;
}

/* Bloco de ilustração da árvore DOM */
#ilustracao-dom p {
  margin-top: 0.4rem;
  margin-bottom: 0.8rem;
}

#ilustracao-dom h3 {
  margin-top: 1.2rem;
}

/* Texto explicativo antes da árvore */
.dom-arvore-texto {
  color: var(--muted);
  font-size: 0.95rem;
}

/* Caixa da árvore DOM */
.dom-arvore {
  background-color: #111827;
  color: #e5e7eb;
  border-color: #333;
  font-size: 0.9rem;
}

.tooltip {
  position: relative;
  cursor: help;
  border-bottom: 1px dotted currentColor;
}

.tooltip .tooltip-texto {
  visibility: hidden;
  opacity: 0;
  background-color: #1e1e2e;
  color: #f8f8f2;
  font-size: 0.85rem;
  line-height: 1.5;
  border-radius: 6px;
  padding: 10px 14px;
  width: 320px;
  position: absolute;
  bottom: 130%;
  left: 50%;
  transform: translateX(-50%);
  box-shadow: 0 4px 12px rgba(0,0,0,0.3);
  transition: opacity 0.2s ease;
  z-index: 100;
}

/* Seta apontando para baixo */
.tooltip .tooltip-texto::after {
  content: '';
  position: absolute;
  top: 100%;
  left: 50%;
  transform: translateX(-50%);
  border: 6px solid transparent;
  border-top-color: #1e1e2e;
}

.tooltip:hover .tooltip-texto {
  visibility: visible;
  opacity: 1;
}

.tooltip {
  position: relative;
  cursor: help;
  border-bottom: 1px dotted currentColor;
  display: inline-block;
}

.fluxo {
  font-weight: bold;
  color: var(--primary-dark);
}