* {
  box-sizing: border-box;
}
body {
  font-family:
    "Inter",
    system-ui,
    -apple-system,
    "Segoe UI",
    Roboto,
    "Helvetica Neue",
    Arial;
  background: #f6f7fb;
  color: #222;
  margin: 0;
  padding: 0;
}
header {
  background: #2d3436;
  color: #fff;
  padding: 1.25rem;
  text-align: center;
}
header h1 {
  margin: 0;
  font-size: 1.5rem;
}
nav {
  margin-top: 0.5rem;
}
nav a {
  color: #fff;
  text-decoration: none;
  margin: 0 8px;
  font-weight: 500;
}
main {
  max-width: 1100px;
  margin: 2rem auto;
  padding: 1rem;
}
footer {
  text-align: center;
  padding: 1rem;
  background: #2d3436;
  color: #fff;
  margin-top: 2rem;
}

.controls {
  display: flex;
  gap: 1rem;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 1rem;
  flex-wrap: wrap;
}
.category-buttons {
  display: flex;
  gap: 0.5rem;
  flex-wrap: wrap;
}
.category-buttons button {
  background: #fff;
  border: 1px solid #e6e9ef;
  padding: 0.45rem 0.75rem;
  border-radius: 8px;
  cursor: pointer;
}
.category-buttons button.active {
  background: #0984e3;
  color: #fff;
  border-color: #0984e3;
}
.search-input {
  padding: 0.5rem 0.75rem;
  border-radius: 8px;
  border: 1px solid #e6e9ef;
  width: 220px;
}

.posts-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.25rem;
}
.post-card {
  background: #fff;
  border-radius: 12px;
  overflow: hidden;
  box-shadow: 0 6px 18px rgba(35, 43, 77, 0.06);
  transition: transform 0.18s ease;
  display: flex;
  flex-direction: column;
}
.post-card:hover {
  transform: translateY(-6px);
}
.post-card img {
  width: 100%;
  height: 170px;
  object-fit: cover;
  display: block;
}
.post-card-content {
  padding: 1rem;
  flex: 1;
  display: flex;
  flex-direction: column;
}
.post-card h3 {
  margin: 0 0 0.5rem 0;
  font-size: 1.05rem;
  color: #2d3436;
}
.meta {
  font-size: 0.9rem;
  color: #888;
  margin-bottom: 0.6rem;
}
.excerpt {
  color: #555;
  flex: 1;
}
.card-footer {
  margin-top: 0.75rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
}
.read-more {
  color: #0984e3;
  text-decoration: none;
  font-weight: 600;
}
.pagination {
  display: flex;
  gap: 0.5rem;
  align-items: center;
  justify-content: center;
  margin-top: 1.25rem;
}
.page-btn {
  padding: 0.5rem 0.75rem;
  border-radius: 8px;
  border: 1px solid #e6e9ef;
  background: #fff;
  cursor: pointer;
}
.page-btn.active {
  background: #0984e3;
  color: #fff;
  border-color: #0984e3;
}

.lightbox {
  display: none;
  position: fixed;
  z-index: 999;
  padding-top: 60px;
  left: 0;
  top: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.9);
}
.lightbox-content {
  margin: auto;
  display: block;
  max-width: 90%;
  max-height: 80vh;
  border-radius: 8px;
  opacity: 0;
  transition: opacity 0.3s ease;
}
.lightbox-content.show {
  opacity: 1;
}
.close {
  position: absolute;
  top: 15px;
  right: 35px;
  color: #fff;
  font-size: 40px;
  cursor: pointer;
}
.prev,
.next {
  cursor: pointer;
  position: absolute;
  top: 50%;
  padding: 16px;
  color: #fff;
  font-size: 30px;
  user-select: none;
}
.prev {
  left: 10px;
}
.next {
  right: 10px;
}
@media (max-width: 540px) {
  .search-input {
    width: 140px;
  }
  .post-card img {
    height: 140px;
  }
}