:root {
  color-scheme: light;
  --bg: #eaf3ff;
  --surface: #d8e7ff;
  --surface-strong: #b5d0ff;
  --text: #002651;
  --text-muted: #4f6f99;
  --accent: #1a66ff;
  --border: rgba(0, 38, 81, 0.12);
  --shadow: 0 18px 50px rgba(0, 38, 81, 0.12);
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: Inter, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  background: linear-gradient(180deg, #edf4ff 0%, #d8e9ff 100%);
  color: var(--text);
}

.page-shell {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

.site-header {
  background: radial-gradient(circle at top left, rgba(22, 102, 255, 0.18), transparent 45%),
              linear-gradient(90deg, #0e4ac3 0%, #1b75ff 100%);
  color: white;
  padding: 2rem 1.5rem;
}

.brand h1 {
  margin: 0;
  font-size: clamp(2rem, 3vw, 3rem);
}

.brand p {
  margin: 0.5rem 0 0;
  color: rgba(255, 255, 255, 0.85);
}

.container {
  width: min(1120px, calc(100% - 2rem));
  margin: 0 auto;
  padding: 2rem 0 3rem;
  flex: 1;
}

.forum-intro {
  background: white;
  border: 1px solid var(--border);
  border-radius: 24px;
  padding: 1.75rem 2rem;
  box-shadow: var(--shadow);
  margin-bottom: 2rem;
}

.forum-intro h2 {
  margin: 0 0 0.5rem;
}

.forum-intro p {
  margin: 0;
  color: var(--text-muted);
}

.forum-topic {
  display: grid;
  gap: 1.5rem;
}

.topic-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: var(--surface);
  padding: 1rem 1.5rem;
  border-radius: 20px;
  border: 1px solid var(--border);
}

.topic-header h3 {
  margin: 0;
  font-size: 1.2rem;
}

.topic-meta {
  display: block;
  margin-top: 0.35rem;
  color: var(--text-muted);
  font-size: 0.95rem;
}

.topic-status {
  background: rgba(26, 102, 255, 0.13);
  color: var(--accent);
  padding: 0.55rem 0.9rem;
  border-radius: 999px;
  font-weight: 600;
  font-size: 0.9rem;
}

.post-card {
  background: white;
  border-radius: 24px;
  border: 1px solid var(--border);
  padding: 1.75rem;
  box-shadow: var(--shadow);
}

.post-author {
  display: flex;
  align-items: center;
  gap: 1rem;
  margin-bottom: 1.5rem;
}

.avatar {
  width: 60px;
  height: 60px;
  border-radius: 20px;
  display: grid;
  place-items: center;
  font-size: 1.5rem;
  font-weight: 700;
  color: white;
  background: linear-gradient(135deg, #1a66ff, #3c8cff);
}

.author-name {
  margin: 0;
  font-size: 1rem;
  font-weight: 700;
}

.author-role {
  margin: 0.25rem 0 0;
  color: var(--text-muted);
  font-size: 0.95rem;
}

.post-content h4 {
  margin-top: 0;
  margin-bottom: 1rem;
  color: #07316c;
}

.post-content p {
  line-height: 1.75;
  margin: 0 0 1rem;
}

.post-content p:last-child {
  margin-bottom: 0;
}

.site-footer {
  text-align: center;
  padding: 1.25rem 1.5rem;
  color: var(--text-muted);
  font-size: 0.95rem;
}

@media (max-width: 720px) {
  .topic-header,
  .forum-intro,
  .post-card {
    padding: 1.25rem;
  }

  .container {
    padding: 1.5rem 0 2rem;
  }
}