:root {
    --blue-dark: #3c5aa6;
    --blue-light: #2a75bb;
  --yellow: #ffcb05;
  --bg: #f5f7ff;
  --text-main: #0f172a;
  --text-soft: #64748b;
  --card-bg: #ffffff;
  --border-soft: #d4defa;
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
    font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

body {
    background: var(--bg);
    color: var(--text-main);
}

/* topo */

.topbar {
    background: linear-gradient(90deg, var(--blue-dark), var(--blue-light));
    color: #fff;
    padding: 12px 20px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.logo-area {
    display: flex;
    align-items: center;
    gap: 10px;
}

.logo-icon {
    width: 36px;
    height: 36px;
}

.topbar h1 {
    font-size: 1.4rem;
}

.nav a {
    color: #fff;
    text-decoration: none;
    margin-left: 16px;
    font-weight: 500;
}

.nav a:hover {
    text-decoration: underline;
}

/* conteúdo */

.container {
    max-width: 960px;
    margin: 24px auto 32px auto;
    padding: 0 16px;
}

.hero {
  background: var(--card-bg);
  border-radius: 12px;
  padding: 20px 18px;
  border: 1px solid var(--border-soft);
  box-shadow: 0 6px 18px rgba(15, 23, 42, 0.06);
  margin-bottom: 24px;
  border-top: 4px solid var(--yellow);
}

.hero h2 {
  font-size: 1.6rem;
  margin-bottom: 8px;
}

.hero p {
  color: var(--text-soft);
}

/* Lista de posts */

.posts {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 18px;
  margin-bottom: 24px;
}

.post-card {
  background: var(--card-bg);
  border-radius: 12px;
  padding: 16px 14px;
  border: 1px solid var(--border-soft);
  box-shadow: 0 4px 14px rgba(15, 23, 42, 0.04);
  position: relative;
}

.post-card h3 {
  font-size: 1.2rem;
  margin-bottom: 6px;
}

.post-card .meta {
  font-size: 0.85rem;
  color: var(--text-soft);
  margin-bottom: 8px;
}

.post-card .excerpt {
  font-size: 0.95rem;
  margin-bottom: 12px;
}

.btn {
  display: inline-block;
  padding: 8px 14px;
  border-radius: 999px;
  border: none;
  background: var(--yellow);
  color: #000;
  font-weight: 600;
  text-decoration: none;
  font-size: 0.9rem;
}

.btn:hover {
  filter: brightness(0.95);
}

/* Seções info */

.info-section {
  background: var(--card-bg);
  border-radius: 12px;
  padding: 18px 16px;
  border: 1px solid var(--border-soft);
  margin-bottom: 16px;
}

.info-section h2 {
  font-size: 1.3rem;
  margin-bottom: 6px;
}

.info-section p {
  color: var(--text-soft);
  margin-bottom: 6px;
}

.info-section ul {
  list-style: disc;
  padding-left: 20px;
}

/* Rodapé */

.footer {
  text-align: center;
  font-size: 0.8rem;
  color: var(--text-soft);
  padding: 12px;
}

/* Responsivo */

@media (max-width: 600px) {
  .topbar {
    flex-direction: column;
    align-items: flex-start;
    gap: 4px;
  }

  .nav a {
    margin-left: 0;
    margin-right: 12px;
  }
}

.blog-filters {
    display: flex;
    gap: 8px;
    margin: 16px 0 18px 0;
    flex-wrap: wrap;
}

.filter-btn {
    padding: 6px 12px;
    border-radius: 999px;
    border: 1px solid var(--border-soft);
    background: #fff;
    color: var(--text-main);
    font-size: 0.9rem;
    cursor: pointer;
}

.filter-btn.active {
    background: var(--blue-light);
    color: #fff;
    border-color: var(--blue-light);
}

#back-to-top {
  position: fixed;
  right: 16px;
  bottom: 16px;
  padding: 8px 12px;
  border-radius: 999px;
  border: none;
  background: var(--yellow);
  color: #000;
  font-weight: 600;
  cursor: pointer;
  font-size: 0.85rem;
  box-shadow: 0 4px 12px rgba(15, 23, 42, 0.3);
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.2s ease, transform 0.2s ease;
  transform: translateY(10px);
}

#back-to-top.visible {
    opacity: 1;
    pointer-events: auto;
    transform: translateY(0);
}