/* Reset & Base Forum Theme */
* { box-sizing: border-box; }
body {
  margin: 0;
  font-family: "Segoe UI", Tahoma, Arial, sans-serif;
  color: #172033;
  background-color: #eef2ff;
  line-height: 1.55;
}
a { color: #4338ca; text-decoration: none; }

/* 1. Header */
header.forum-header {
  background: #4338ca;
  color: #ffffff;
  padding: 16px 24px;
}
.forum-topbar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 16px;
  max-width: 1280px;
  margin: 0 auto;
}
.forum-brand h1 { margin: 0; font-size: 24px; }
.forum-brand p { margin: 2px 0 0; font-size: 13px; color: #c7d2fe; }
.badge-online-counter {
  display: inline-block;
  background: #c7d2fe;
  color: #312e81;
  font-size: 11.5px;
  font-weight: 700;
  padding: 4px 10px;
  border-radius: 999px;
  margin-right: 10px;
}
.active-posts-today { font-size: 13px; color: #e0e7ff; }

/* 2. Nav Flexbox */
nav.forum-nav {
  background: #3730a3;
  padding: 0 20px;
}
ul.nav-subforums {
  display: flex;
  justify-content: space-around;
  align-items: center;
  flex-wrap: wrap;
  list-style: none;
  margin: 0;
  padding: 10px 0;
}
ul.nav-subforums li a {
  color: #ffffff;
  font-weight: 600;
  font-size: 14px;
  padding: 6px 12px;
  border-radius: 4px;
}
ul.nav-subforums li a:hover {
  background: #4338ca;
}

/* 3. Main 2 cột Flexbox */
main.forum-main-layout {
  padding: 24px;
  max-width: 1280px;
  margin: 0 auto;
}
.forum-two-columns {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 24px;
  flex-wrap: wrap;
}
.col-thread-stream {
  flex: 3.5 1 660px;
}
.forum-welcome-hero {
  background: #ffffff;
  border: 1px solid #c7d2fe;
  border-left: 5px solid #4338ca;
  border-radius: 8px;
  padding: 18px 20px;
  margin-bottom: 18px;
}
.hero-tag {
  display: inline-block;
  background: #e0e7ff;
  color: #4338ca;
  font-size: 11px;
  font-weight: 700;
  padding: 3px 8px;
  border-radius: 4px;
  margin-bottom: 6px;
}
.forum-welcome-hero h2 { margin: 0 0 6px; font-size: 19px; color: #0f172a; }
.forum-welcome-hero p { margin: 0; font-size: 13px; color: #475569; }

/* 6 Thẻ bài viết Flexbox không đều nhau */
.threads-flex-group {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-start;
  align-items: stretch;
  gap: 16px;
}
.thread-box {
  background: #ffffff;
  border: 1px solid #c7d2fe;
  border-radius: 8px;
  padding: 16px;
  box-shadow: 0 1px 3px rgba(67, 56, 202, 0.05);
}
.thread-box.g1 { flex: 2.8 1 340px; }
.thread-box.g2 { flex: 1 1 160px; }
.thread-box.g3 { flex: 1.5 1 210px; align-self: stretch; }
.thread-box.g4 { flex: 1.9 1 250px; }
.thread-box.g5 { flex: 1.1 1 170px; }
.thread-box.g6.pinned-thread {
  flex: 2.6 1 320px;
  order: -1;
  background: #faf5ff;
  border-color: #d8b4fe;
}
.thread-type-tag {
  display: inline-block;
  font-size: 10.5px;
  font-weight: 700;
  padding: 2px 7px;
  border-radius: 4px;
  background: #e0e7ff;
  color: #3730a3;
  margin-bottom: 6px;
}
.hot-tag { background: #7e22ce; color: #ffffff; }
.thread-box h3 { margin: 0 0 6px; font-size: 15px; color: #312e81; }
.thread-box p { margin: 0 0 8px; font-size: 13px; color: #475569; }
.thread-box code { background: #f1f5f9; padding: 2px 5px; border-radius: 4px; font-size: 12px; color: #b91c1c; }
.thread-meta { font-size: 12px; color: #64748b; }
.thread-meta span { margin-right: 12px; }

/* Display none */
.moderator-logs-hidden { display: none; }

.col-forum-stats {
  flex: 1 1 240px;
  background: #ffffff;
  border: 1px solid #c7d2fe;
  border-radius: 8px;
  padding: 18px;
  align-self: flex-start;
}
.col-forum-stats h3 { margin: 0 0 12px; font-size: 16px; color: #3730a3; }
.tag-cloud-wrap { margin-bottom: 18px; }
.tag-pill {
  display: inline-block;
  background: #e0e7ff;
  color: #4338ca;
  font-size: 12px;
  font-weight: 600;
  padding: 4px 8px;
  border-radius: 6px;
  margin: 0 4px 6px 0;
}
.col-forum-stats p { margin: 6px 0; font-size: 13px; color: #334155; }

/* 4. Footer 3 cột */
footer.forum-footer {
  background: #1e1b4b;
  color: #e0e7ff;
  padding: 30px 24px;
  margin-top: 36px;
}
.forum-footer-inner {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  flex-wrap: wrap;
  gap: 20px;
  max-width: 1280px;
  margin: 0 auto;
}
.forum-col { flex: 1 1 220px; }
.forum-col h4 { margin: 0 0 10px; font-size: 15px; color: #ffffff; }
.forum-col p { margin: 0; font-size: 13px; color: #c7d2fe; }
.forum-col ul { list-style: none; margin: 0; padding: 0; }
.forum-col ul li { margin-bottom: 6px; font-size: 13px; color: #c7d2fe; }