/* ============================================================
   Two-column layout
   ============================================================ */

#article {
  padding-top: 0;
  overflow: visible;
  margin-top: 80px;
}

#article .container {
  padding-left: 0;
  padding-right: 0;
}

header .logo {
  margin: 0;
}

.blog-feed {
  padding-top: 40px;
}

.blog-layout {
  display: grid;
  grid-template-columns: 1fr 260px;
  gap: 60px;
}

/* ============================================================
   Article feed
   ============================================================ */

.blog-article-item {
  display: block;
  text-decoration: none;
  color: inherit;
  margin-bottom: 48px;
  padding-bottom: 48px;
  border-bottom: 1px solid var(--color-border);
}

.blog-article-item:hover {
  text-decoration: none;
}

.blog-article-img {
  width: 100%;
  height: 360px;
  background-size: cover;
  background-position: center;
  background-color: var(--color-border);
  margin-bottom: 18px;
  border: 1px solid var(--color-border);
}

.blog-article-meta {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 10px;
}

.blog-cat-tag {
  font-family: var(--font-ui);
  font-size: 13px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--color-brand);
}

.blog-article-date {
  font-family: var(--font-ui);
  font-size: 13px;
  color: #777;
}

.blog-article-title {
  font-family: var(--font-heading);
  font-size: 1.65rem;
  font-weight: 700;
  color: var(--color-heading);
  line-height: 1.4;
  margin-bottom: 10px;
}

.blog-article-item:hover .blog-article-title {
  color: var(--color-heading);
}

.blog-article-subtitle {
  font-size: 17px;
  color: #555;
  line-height: 1.7;
  margin-bottom: 16px;
}

.blog-article-excerpt {
  font-size: 16px;
  color: #888;
  line-height: 1.7;
  margin-bottom: 6px;
}

.blog-read-more {
  color: var(--color-brand);
  font-family: var(--font-ui);
  font-size: 13px;
  white-space: nowrap;
}

.blog-article-item:hover .blog-read-more {
  text-decoration: underline;
}

.blog-article-pub {
  font-family: var(--font-ui);
  font-size: 13px;
  color: #aaa;
  display: block;
  margin-top: 4px;
}

/* ============================================================
   Sidebar
   ============================================================ */

.blog-sidebar {
  position: sticky;
  top: 24px;
  align-self: start;
  padding-top: 40px;
}

.blog-sidebar * {
  margin-top: 0;
}

.blog-intro {
  display: flex;
  flex-direction: column;
  gap: 16px;
  padding-top: 0;
  padding-bottom: 20px;
  margin-top: 0;
  margin-bottom: 20px;
}

.blog-avatar {
  width: 112px;
  height: 112px;
  border-radius: 50%;
  object-fit: cover;
}

.blog-intro-desc {
  color: #555;
  margin: 4px 0 0;
  font-size: 16px;
  line-height: 1.7;
}

.sidebar-section {
  margin-bottom: 36px;
}

.blog-sidebar .section-title {
  font-family: var(--font-ui);
  font-size: 13px;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: #999;
  margin-bottom: 0;
  margin-top: 0;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--color-border);
}

.filter-group {
  display: flex;
  flex-direction: column;
  gap: 10px;
  margin-top: 14px;
}

.filter-btn {
  background: none;
  border: none;
  padding: 0;
  text-align: left;
  cursor: pointer;
  font-family: var(--font-ui);
  font-size: 15px;
  color: #aaa;
  line-height: 1.8;
}

.filter-btn.active {
  color: var(--color-text-medium);
  font-weight: 600;
}

.filter-btn:hover {
  color: var(--color-heading);
}

.filter-btn:focus {
  outline: none;
}

.btn-count {
  font-size: 0.88em;
  opacity: 0.6;
}

/* ============================================================
   Author name
   ============================================================ */

.medium-link {
  color: inherit;
  text-decoration: none;
  font-size: 0.85em;
  font-family: var(--font-ui);
  font-weight: 400;
}

.medium-link:hover {
  color: var(--color-brand);
  text-decoration: underline;
}

.name {
  margin-top: 0;
  font-weight: 600;
  font-size: 20px;
  font-family: var(--font-heading);
  margin-bottom: 0;
}

/* ============================================================
   Responsive
   ============================================================ */

@media (max-width: 900px) {
  .blog-layout {
    grid-template-columns: 1fr;
  }

  .blog-feed {
    order: 1;
  }

  .blog-sidebar {
    order: 2;
    position: static;
    width: 100%;
    max-height: none;
    border-top: 1px solid var(--color-border);
    border-bottom: none;
    padding-top: 24px;
    padding-bottom: 0;
    margin-top: 8px;
    margin-bottom: 0;
  }

  .blog-intro {
    flex-direction: row;
    align-items: center;
    border-bottom: none;
    margin-bottom: 16px;
    padding-bottom: 0;
  }

  .sidebar-section {
    margin-bottom: 20px;
  }

  .sidebar-section:first-of-type {
    margin-top: 8px;
  }

  .filter-group {
    flex-direction: row;
    flex-wrap: wrap;
    gap: 4px 16px;
  }

  .blog-feed {
    padding-top: 0;
  }
}

@media (max-width: 768px) {
  #article {
    margin-top: 48px;
    margin-bottom: 48px;
  }

  #article .container {
    padding-left: 16px;
    padding-right: 16px;
  }

  .blog-article-item {
    margin-bottom: 36px;
    padding-bottom: 36px;
  }

  .blog-article-img {
    height: 200px;
  }

  .blog-article-title {
    font-size: 1.3rem;
  }

  .blog-article-subtitle {
    font-size: 15px;
    margin-bottom: 10px;
  }

  .blog-article-excerpt {
    font-size: 14px;
  }

  .blog-read-more {
    display: inline-block;
    margin-top: 0;
  }
}