/* ===== RESET & GLOBAL ===== */
* {
  box-sizing: border-box;
}
body {
  margin: 0;
  font-family: 'Segoe UI', Arial, sans-serif;
  background: #f5f8fb;
  color: #111;
}

/* ======= KHUNG TỔNG TRANG ======= */
.page-container {
  width: 80%;
  margin: 0 auto;
  background: #f5f8fb;
}

/* ===== HEADER ===== */
.logo-bar {
  background: linear-gradient(90deg, #0056b3, #007bff);
  color: #fff;
  text-align: center;
  padding: 25px 0;
  box-shadow: 0 2px 6px rgba(0,0,0,0.15);
  border-radius: 0 0 8px 8px;
}

.logo {
  margin: 0;
  font-size: 30px;
  font-weight: 700;
  letter-spacing: 1px;
}

/* ===== MENU NGANG ===== */
.main-nav-wrapper {
  width: 80%;
  margin: 0 auto;
}
.main-nav {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: #004b80; /* giữ lại màu nền khi cuộn */
  box-shadow: 0 2px 6px rgba(0, 0, 0, 0.15); /* hiệu ứng bóng nhẹ khi dính trên cùng */
}
.main-nav ul {
  display: flex;
  gap: 25px;
  list-style: none;
  margin: 0;
  padding: 0;
}
.main-nav a {
  color: #eaf3ff;
  text-decoration: none;
  font-weight: 600;
  padding: 14px 0;
  position: relative;
  transition: color 0.2s ease;
}
.main-nav a::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 50%;
  width: 0;
  height: 2px;
  background: #00bfff;
  transform: translateX(-50%);
  transition: width 0.3s ease;
}
.main-nav a:hover { color: #fff; }
.main-nav a:hover::after { width: 60%; }

/* ======= LAYOUT 2 CỘT ======= */
.news-wrapper {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 30px;
  padding: 30px 0;
}
.news-left {
  flex: 0 0 68%;
}
.news-right {
  flex: 0 0 28%;
}

/* ===== KHỐI TIN NÓNG ===== */
.hot-news {
  display: flex;
  flex-direction: column;
  gap: 20px;
  margin-bottom: 40px;
}
.hot-item {
  display: flex;
  gap: 20px;
  background: #eef5ff;
  border-radius: 10px;
  padding: 15px;
  box-shadow: 0 2px 5px rgba(0,0,0,0.1);
  transition: all 0.2s ease;
}
.hot-item:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 10px rgba(0,0,0,0.12);
}
.hot-thumb {
  flex: 0 0 35%;
}
.hot-thumb img {
  width: 100%;
  height: 200px;
  object-fit: cover;
  border-radius: 8px;
}
.hot-content {
  flex: 1;
}
.hot-content h3 {
  font-size: 20px;
  font-weight: 600;
  color: #004aad;
  margin-bottom: 8px;
}
.hot-content p {
  color: #333;
  font-size: 15px;
  text-align: justify;
}

/* ===== GRID BÀI VIẾT ===== */
.sub-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 20px;
  margin-top: 20px;
}
.sub-grid article {
  background: #eef5ff;
  border-radius: 10px;
  overflow: hidden;
  box-shadow: 0 2px 5px rgba(0,0,0,0.08);
  transition: 0.2s;
  position: relative;
  display: flex;
  flex-direction: column;
}
.sub-grid article:hover {
  transform: translateY(-3px);
  box-shadow: 0 4px 10px rgba(0,0,0,0.12);
}
.sub-grid img {
  width: 100%;
  height: 180px;
  object-fit: cover;
  border-bottom: 1px solid #ddd;
}
.cat-label {
  position: absolute;
  top: 10px;
  left: 10px;
  background: #004aad;
  color: #fff;
  font-size: 12px;
  padding: 4px 8px;
  border-radius: 4px;
}
.sub-grid h4 {
  font-size: 17px;
  color: #004aad;
  font-weight: 600;
  padding: 10px 12px 5px;
}
.sub-grid p {
  font-size: 14px;
  color: #333;
  padding: 0 12px 10px;
  text-align: justify;
  flex-grow: 1;
}
.see-more {
  text-align: right;
  padding: 8px 12px 12px;
  color: #006aff;
  font-weight: 500;
  text-decoration: none;
}
.see-more:hover { color: #0040a8; text-decoration: underline; }

/* ===== SIDEBAR ===== */
.sidebar-tab {
  border: 1px solid #cfe0ff;
  border-radius: 8px;
  background: #fff;
  box-shadow: 0 1px 4px rgba(0,0,0,0.1);
}
.tab-header {
  display: flex;
  border-bottom: 2px solid #e0e0e0;
}
.tab {
  flex: 1;
  background: #f8f9fa;
  border: none;
  padding: 10px;
  font-weight: bold;
  color: #004ea4;
  cursor: pointer;
  transition: 0.3s;
}
.tab.active {
  color: #007bff;
  border-bottom: 3px solid #007bff;
  background: #fff;
}
.tab-content ul {
  list-style: none;
  padding: 12px;
  margin: 0;
}
.tab-content li { margin-bottom: 8px; }
.tab-content a {
  text-decoration: none;
  color: #222;
}
.tab-content a:hover { color: #007bff; }

/* ===== CỘT PHẢI: VĂN HÓA & THƯ VIỆN ===== */
.culture-card img {
  width: 100%;
  border-radius: 6px;
}
.library-list {
  list-style: none;
  padding: 0;
}
.library-list li {
  display: flex;
  align-items: center;
  margin-bottom: 8px;
}
.library-list .thumb {
  width: 45px;
  height: 45px;
  object-fit: cover;
  border-radius: 4px;
  margin-right: 10px;
}
.library-list a {
  text-decoration: none;
  color: #0044cc;
}
.library-list a:hover {
  text-decoration: underline;
}

/* ===== FOOTER ===== */
.site-footer {
  width: 80%;
  margin: 40px auto 0;
  background: #004b80;
  color: #0e1f35;
  text-align: center;
  padding: 25px;
  font-size: 14px;
  border-radius: 8px 8px 0 0;
}

/* ======= RESPONSIVE ======= */


@media (max-width: 600px) {
  .page-container,
  .main-nav-wrapper,
  .site-footer {
    width: 95%;
    background-color: #0044cc;
  }
  .news-wrapper {
    padding: 20px 0;
    gap: 20px;
  }
  .hot-thumb img {
    height: auto;
  }
  .logo {
    font-size: 24px;
  }
  .main-nav ul {
    flex-wrap: wrap;
    gap: 15px;
  }
}