/* ============================================================
   components.css — Cards, Filters, Timeline, Search, etc.
   ============================================================ */

/* ─── FILTER COMPONENTS ────────────────────────────────────── */
.filter-container {
  margin-bottom: 40px;
}

.filter-tabs {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
  justify-content: center;
  margin-bottom: 16px;
}

.filter-tab {
  padding: 8px 20px;
  border-radius: 20px;
  border: 1px solid var(--color-border);
  background: transparent;
  color: var(--color-text-secondary);
  cursor: pointer;
  font-size: 0.85rem;
  font-weight: 500;
  font-family: var(--font-primary);
  transition: all var(--transition);
  white-space: nowrap;
}

.filter-tab:hover {
  border-color: var(--color-primary);
  color: var(--color-primary);
}

.filter-tab.active {
  background: rgba(var(--color-primary-rgb), 0.12);
  border-color: var(--color-primary);
  color: var(--color-primary);
}

.difficulty-filters {
  display: flex;
  gap: 8px;
  justify-content: center;
}

.difficulty-filter {
  padding: 6px 18px;
  border-radius: 20px;
  border: 1px solid var(--color-border);
  background: transparent;
  color: var(--color-text-secondary);
  cursor: pointer;
  font-size: 0.8rem;
  font-weight: 500;
  font-family: var(--font-primary);
  transition: all var(--transition);
}

.difficulty-filter:hover {
  border-color: var(--color-primary);
  color: var(--color-primary);
}

.difficulty-filter.active {
  background: rgba(var(--color-primary-rgb), 0.12);
  border-color: var(--color-primary);
  color: var(--color-primary);
}

/* ─── SEARCH MODAL ─────────────────────────────────────────── */
.search-modal {
  position: fixed;
  inset: 0;
  z-index: 2000;
  background: rgba(6, 9, 17, 0.85);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  display: flex;
  align-items: flex-start;
  justify-content: center;
  padding-top: 100px;
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--transition);
}

.search-modal.active {
  opacity: 1;
  pointer-events: all;
}

.search-modal__container {
  width: 100%;
  max-width: 640px;
  padding: 0 24px;
}

.search-modal__close {
  position: fixed;
  top: 20px;
  right: 24px;
  background: none;
  border: none;
  color: var(--color-text-secondary);
  cursor: pointer;
  font-size: 2rem;
  line-height: 1;
  transition: color var(--transition);
  padding: 4px;
}

.search-modal__close:hover {
  color: var(--color-text-heading);
}

.search-modal__input-wrapper {
  position: relative;
  margin-bottom: 16px;
}

.search-modal__icon {
  position: absolute;
  left: 18px;
  top: 50%;
  transform: translateY(-50%);
  color: var(--color-text-secondary);
  pointer-events: none;
}

.search-modal__input {
  width: 100%;
  padding: 16px 20px 16px 52px;
  background: var(--color-bg-section-alt);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  color: var(--color-text-heading);
  font-size: 1.05rem;
  font-family: var(--font-primary);
  outline: none;
  transition: border-color var(--transition), box-shadow var(--transition);
}

.search-modal__input:focus {
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(var(--color-primary-rgb), 0.12);
}

.search-modal__input::placeholder {
  color: var(--color-text-secondary);
}

.search-modal__results {
  max-height: 420px;
  overflow-y: auto;
  background: var(--color-bg-section-alt);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  overflow: hidden;
}

.search-modal__result {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 14px 18px;
  cursor: pointer;
  transition: background var(--transition);
  border-bottom: 1px solid var(--color-border);
}

.search-modal__result:last-child {
  border-bottom: none;
}

.search-modal__result:hover {
  background: rgba(var(--color-primary-rgb), 0.06);
}

/* ─── COURSE CARD ──────────────────────────────────────────── */
.course-card {
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  overflow: hidden;
  transition: transform var(--transition), border-color var(--transition), box-shadow var(--transition);
  display: flex;
  flex-direction: column;
}

.course-card:hover {
  transform: translateY(-5px);
  border-color: var(--color-border-hover);
  box-shadow: var(--shadow-glow);
}

.course-card__image {
  height: 180px;
  background: linear-gradient(135deg, rgba(var(--color-primary-rgb), 0.15), rgba(var(--color-accent-rgb), 0.15));
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}

/* Circuit board pattern overlay */
.course-card__image::after {
  content: '';
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(var(--color-primary-rgb), 0.06) 1px, transparent 1px),
    linear-gradient(90deg, rgba(var(--color-primary-rgb), 0.06) 1px, transparent 1px);
  background-size: 20px 20px;
}

.course-card__badge {
  position: absolute;
  top: 12px;
  right: 12px;
  z-index: 1;
}

.course-card__content {
  padding: 20px;
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.course-card__category {
  margin-bottom: 4px;
}

.course-card__title {
  font-size: 1.05rem;
  font-weight: 600;
  color: var(--color-text-heading);
  line-height: 1.35;
  margin: 0;
}

.course-card__description {
  font-size: 0.865rem;
  color: var(--color-text-secondary);
  line-height: 1.55;
  flex: 1;
  margin: 0;
}

.course-card__meta {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin-top: 4px;
}

.course-card__meta-item {
  display: flex;
  align-items: center;
  gap: 5px;
  font-size: 0.8rem;
  color: var(--color-text-secondary);
}

.course-card__meta-item svg {
  color: var(--color-primary);
  flex-shrink: 0;
}

.course-card__footer {
  margin-top: 16px;
}

.course-card__btn {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
}

/* ─── EQUIPMENT CARD ───────────────────────────────────────── */
.equipment-card {
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  overflow: hidden;
  transition: transform var(--transition), border-color var(--transition), box-shadow var(--transition);
  display: flex;
  flex-direction: column;
}

.equipment-card:hover {
  transform: translateY(-5px);
  border-color: var(--color-border-hover);
  box-shadow: var(--shadow-glow);
}

.equipment-card__image {
  height: 150px;
  background: linear-gradient(135deg, rgba(var(--color-accent-rgb), 0.12), rgba(var(--color-primary-rgb), 0.12));
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}

.equipment-card__image::after {
  content: '';
  position: absolute;
  inset: 0;
  background-image:
    radial-gradient(circle, rgba(var(--color-primary-rgb), 0.08) 1px, transparent 1px);
  background-size: 16px 16px;
}

.equipment-card__badge {
  position: absolute;
  top: 10px;
  right: 10px;
  z-index: 1;
}

.equipment-card__content {
  padding: 20px;
  flex: 1;
  display: flex;
  flex-direction: column;
}

.equipment-card__title {
  font-size: 1.05rem;
  font-weight: 600;
  color: var(--color-text-heading);
  margin-bottom: 10px;
}

.equipment-card__description {
  font-size: 0.865rem;
  color: var(--color-text-secondary);
  line-height: 1.55;
  margin-bottom: 16px;
}

.equipment-card__specs {
  list-style: none;
  margin-bottom: 16px;
}

.equipment-card__spec {
  font-size: 0.8rem;
  color: var(--color-text-secondary);
  padding: 3px 0;
  padding-left: 14px;
  position: relative;
}

.equipment-card__spec::before {
  content: '▸';
  position: absolute;
  left: 0;
  color: var(--color-primary);
  font-size: 0.7rem;
  top: 4px;
}

.equipment-card__applications {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-top: auto;
}

.equipment-card__tag {
  font-size: 0.72rem;
  padding: 3px 10px;
  background: rgba(var(--color-primary-rgb), 0.08);
  color: var(--color-primary);
  border: 1px solid rgba(var(--color-primary-rgb), 0.15);
  border-radius: 12px;
}

/* ─── POST CARD ────────────────────────────────────────────── */
.post-card {
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  overflow: hidden;
  transition: transform var(--transition), border-color var(--transition), box-shadow var(--transition);
  display: flex;
  flex-direction: column;
}

.post-card:hover {
  transform: translateY(-5px);
  border-color: var(--color-border-hover);
  box-shadow: var(--shadow-glow);
}

.post-card__image {
  height: 200px;
  background: linear-gradient(135deg, rgba(var(--color-primary-rgb), 0.12), rgba(var(--color-accent-rgb), 0.2));
  position: relative;
}

.post-card__image::after {
  content: '';
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(45deg, rgba(var(--color-primary-rgb), 0.04) 25%, transparent 25%),
    linear-gradient(-45deg, rgba(var(--color-primary-rgb), 0.04) 25%, transparent 25%);
  background-size: 24px 24px;
}

.post-card__category {
  position: absolute;
  top: 14px;
  left: 14px;
  z-index: 1;
}

.post-card__content {
  padding: 22px;
  flex: 1;
  display: flex;
  flex-direction: column;
}

.post-card__title {
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--color-text-heading);
  margin-bottom: 10px;
  line-height: 1.35;
}

.post-card__excerpt {
  font-size: 0.875rem;
  color: var(--color-text-secondary);
  line-height: 1.6;
  margin-bottom: 18px;
  flex: 1;
}

.post-card__meta {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
  font-size: 0.8rem;
  color: var(--color-text-secondary);
  margin-bottom: 18px;
}

.post-card__meta-item {
  display: flex;
  align-items: center;
  gap: 5px;
}

.post-card__meta-item svg {
  color: var(--color-primary);
  flex-shrink: 0;
}

.post-card__footer {
  margin-top: auto;
}

.post-card__btn {
  width: 100%;
}

/* ─── TOPIC CARD ───────────────────────────────────────────── */
.topic-card {
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 32px 24px;
  text-align: center;
  cursor: pointer;
  transition: transform var(--transition), border-color var(--transition), box-shadow var(--transition);
}

.topic-card:hover {
  transform: translateY(-5px);
  border-color: var(--color-border-hover);
  box-shadow: var(--shadow-glow);
}

.topic-card__icon {
  width: 56px;
  height: 56px;
  margin: 0 auto 18px;
  background: rgba(var(--color-primary-rgb), 0.1);
  border: 1px solid rgba(var(--color-primary-rgb), 0.15);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-primary);
  transition: background var(--transition), border-color var(--transition);
}

.topic-card:hover .topic-card__icon {
  background: rgba(var(--color-primary-rgb), 0.18);
  border-color: rgba(var(--color-primary-rgb), 0.4);
}

.topic-card__title {
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--color-text-heading);
  margin-bottom: 8px;
}

.topic-card__description {
  font-size: 0.83rem;
  color: var(--color-text-secondary);
  line-height: 1.55;
}

/* ─── TIMELINE ─────────────────────────────────────────────── */
.timeline {
  position: relative;
  max-width: 880px;
  margin: 0 auto;
}

.timeline-line {
  position: absolute;
  left: 50%;
  top: 0;
  bottom: 0;
  width: 2px;
  background: linear-gradient(to bottom, transparent, var(--color-primary) 10%, var(--color-primary) 90%, transparent);
  transform: translateX(-50%);
  z-index: 0;
}

.timeline-item {
  display: flex;
  justify-content: flex-end;
  padding: 10px 0;
  width: 50%;
  position: relative;
  padding-right: 40px;
}

.timeline-item--right {
  justify-content: flex-start;
  margin-left: 50%;
  padding-right: 0;
  padding-left: 40px;
}

.timeline-item__marker {
  position: absolute;
  right: -8px;
  top: 50%;
  transform: translateY(-50%);
  width: 16px;
  height: 16px;
  background: var(--color-primary);
  border-radius: 50%;
  border: 3px solid var(--color-bg-dark);
  z-index: 2;
  box-shadow: 0 0 12px rgba(var(--color-primary-rgb), 0.5);
  animation: pulse-glow 3s ease-in-out infinite;
}

.timeline-item--right .timeline-item__marker {
  right: auto;
  left: -8px;
}

.timeline-item__content {
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 22px 24px;
  max-width: calc(100% - 12px);
  transition: border-color var(--transition), box-shadow var(--transition);
}

.timeline-item__content:hover {
  border-color: var(--color-border-hover);
  box-shadow: var(--shadow-glow);
}

.timeline-item__year {
  display: inline-block;
  background: rgba(var(--color-primary-rgb), 0.12);
  color: var(--color-primary);
  border: 1px solid rgba(var(--color-primary-rgb), 0.2);
  padding: 3px 12px;
  border-radius: 12px;
  font-size: 0.82rem;
  font-weight: 600;
  margin-bottom: 10px;
}

.timeline-item__title {
  font-size: 1rem;
  font-weight: 600;
  color: var(--color-text-heading);
  margin-bottom: 8px;
}

.timeline-item__description {
  font-size: 0.865rem;
  color: var(--color-text-secondary);
  line-height: 1.6;
}

/* ─── HARDWARE / SYSTEM CARDS ──────────────────────────────── */
.system-card {
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 28px;
  transition: transform var(--transition), border-color var(--transition), box-shadow var(--transition);
}

.system-card:hover {
  transform: translateY(-3px);
  border-color: var(--color-border-hover);
  box-shadow: var(--shadow-glow);
}

.system-card__icon {
  width: 48px;
  height: 48px;
  background: rgba(var(--color-primary-rgb), 0.1);
  border: 1px solid rgba(var(--color-primary-rgb), 0.15);
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-primary);
  margin-bottom: 18px;
  flex-shrink: 0;
}

.system-card__title {
  font-size: 1.05rem;
  font-weight: 600;
  color: var(--color-text-heading);
  margin-bottom: 10px;
}

.system-card__description {
  font-size: 0.875rem;
  color: var(--color-text-secondary);
  line-height: 1.6;
  margin-bottom: 18px;
}

.system-card__components {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.system-card__component {
  font-size: 0.8rem;
  color: var(--color-text-secondary);
  padding-left: 14px;
  position: relative;
}

.system-card__component::before {
  content: '▸';
  position: absolute;
  left: 0;
  color: var(--color-primary);
  font-size: 0.7rem;
  top: 2px;
}

/* ─── SYSTEM PIPELINE ──────────────────────────────────────── */
.system-pipeline {
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 36px 32px;
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  margin-bottom: 24px;
}

.pipeline-title {
  font-size: 1rem;
  font-weight: 600;
  color: var(--color-primary);
  margin-bottom: 24px;
  text-align: center;
}

.pipeline-steps {
  display: flex;
  align-items: center;
  justify-content: center;
  flex-wrap: wrap;
  gap: 0;
}

.pipeline-step {
  background: rgba(var(--color-primary-rgb), 0.1);
  border: 1px solid rgba(var(--color-primary-rgb), 0.25);
  color: var(--color-primary);
  font-weight: 600;
  font-size: 0.875rem;
  padding: 12px 22px;
  border-radius: var(--radius-sm);
  text-align: center;
  min-width: 110px;
  white-space: nowrap;
}

.pipeline-arrow {
  color: var(--color-text-secondary);
  font-size: 1.25rem;
  padding: 0 10px;
  display: flex;
  align-items: center;
  flex-shrink: 0;
}

/* ─── ABOUT SECTION ────────────────────────────────────────── */
.about-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 64px;
  align-items: center;
}

.about-content h3 {
  color: var(--color-text-heading);
  font-size: 1.2rem;
  margin-top: 32px;
  margin-bottom: 14px;
}

.about-content h3:first-child {
  margin-top: 0;
}

.about-content p {
  color: var(--color-text-secondary);
  line-height: 1.75;
  margin-bottom: 14px;
  font-size: 0.95rem;
}

.about-features {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
  margin-top: 8px;
}

.about-feature {
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 20px;
  transition: border-color var(--transition);
}

.about-feature:hover {
  border-color: var(--color-border-hover);
}

.about-feature__icon {
  width: 40px;
  height: 40px;
  background: rgba(var(--color-primary-rgb), 0.1);
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-primary);
  margin-bottom: 12px;
}

.about-feature__title {
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--color-text-heading);
  margin-bottom: 6px;
}

.about-feature__text {
  font-size: 0.83rem;
  color: var(--color-text-secondary);
  line-height: 1.5;
}

.about-tech {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 8px;
}

.about-tech__item {
  padding: 7px 16px;
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: 20px;
  font-size: 0.82rem;
  color: var(--color-text-secondary);
  transition: all var(--transition);
  cursor: default;
}

.about-tech__item:hover {
  border-color: var(--color-primary);
  color: var(--color-primary);
  background: rgba(var(--color-primary-rgb), 0.06);
}

.about-visual {
  display: flex;
  align-items: center;
  justify-content: center;
}

.about-visual svg {
  max-width: 100%;
  height: auto;
  filter: drop-shadow(0 0 20px rgba(var(--color-primary-rgb), 0.15));
}

/* ─── CONTACT SECTION ──────────────────────────────────────── */
.contact-wrapper {
  text-align: center;
  max-width: 600px;
  margin: 0 auto;
}

.contact-text {
  color: var(--color-text-secondary);
  font-size: 1.05rem;
  line-height: 1.75;
  margin-bottom: 36px;
}

.contact-actions {
  display: flex;
  gap: 16px;
  justify-content: center;
  margin-bottom: 48px;
  flex-wrap: wrap;
}

.contact-social {
  display: flex;
  gap: 16px;
  justify-content: center;
  flex-wrap: wrap;
}

.contact-social__link {
  width: 46px;
  height: 46px;
  border-radius: 50%;
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-text-secondary);
  transition: all var(--transition);
  text-decoration: none;
}

.contact-social__link:hover {
  border-color: var(--color-primary);
  color: var(--color-primary);
  background: rgba(var(--color-primary-rgb), 0.1);
  transform: translateY(-2px);
}

/* ─── POST DETAIL PAGE ─────────────────────────────────────── */
.post-detail {
  max-width: 820px;
  margin: 0 auto;
  padding: calc(var(--navbar-height) + 48px) 24px 80px;
}

.post-detail__back {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  color: var(--color-text-secondary);
  text-decoration: none;
  margin-bottom: 32px;
  font-size: 0.9rem;
  font-weight: 500;
  transition: color var(--transition);
}

.post-detail__back:hover {
  color: var(--color-primary);
}

.post-detail__header {
  margin-bottom: 40px;
}

.post-detail__category {
  display: inline-block;
  margin-bottom: 16px;
}

.post-detail__title {
  font-size: clamp(1.75rem, 4vw, 2.5rem);
  margin-bottom: 20px;
  line-height: 1.2;
}

.post-detail__meta {
  display: flex;
  gap: 20px;
  flex-wrap: wrap;
  color: var(--color-text-secondary);
  font-size: 0.875rem;
  margin-bottom: 24px;
}

.post-detail__meta-item {
  display: flex;
  align-items: center;
  gap: 6px;
}

.post-detail__meta-item svg {
  color: var(--color-primary);
}

.post-detail__tags {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.post-detail__tag {
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  padding: 4px 14px;
  border-radius: var(--radius-sm);
  font-size: 0.82rem;
  color: var(--color-text-secondary);
}

.post-detail__cover {
  width: 100%;
  height: 300px;
  background: linear-gradient(135deg, rgba(var(--color-primary-rgb), 0.15), rgba(var(--color-accent-rgb), 0.2));
  border-radius: var(--radius-lg);
  margin-bottom: 48px;
  position: relative;
  overflow: hidden;
}

.post-detail__cover::after {
  content: '';
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(var(--color-primary-rgb), 0.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(var(--color-primary-rgb), 0.05) 1px, transparent 1px);
  background-size: 24px 24px;
}

.post-detail__content {
  color: var(--color-text);
  line-height: 1.8;
  font-size: 1.05rem;
}

.post-detail__content h2 {
  font-size: 1.6rem;
  color: var(--color-text-heading);
  margin: 48px 0 16px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--color-border);
}

.post-detail__content h3 {
  font-size: 1.2rem;
  color: var(--color-text-heading);
  margin: 36px 0 12px;
}

.post-detail__content p {
  margin-bottom: 18px;
  color: var(--color-text);
}

.post-detail__content ul,
.post-detail__content ol {
  margin-bottom: 18px;
  padding-left: 24px;
}

.post-detail__content li {
  margin-bottom: 8px;
  color: var(--color-text-secondary);
  line-height: 1.6;
}

.post-detail__content strong {
  color: var(--color-text-heading);
  font-weight: 600;
}

.post-detail__content blockquote {
  border-left: 3px solid var(--color-primary);
  padding: 16px 20px;
  margin: 28px 0;
  background: rgba(var(--color-primary-rgb), 0.05);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  font-style: italic;
  color: var(--color-text-secondary);
}

.post-detail__content pre {
  margin: 24px 0;
}