/**
 * KineticUltra — Single article page (The Kinetic Command).
 * Structural styles: hero, layout, sidebar, TOC, newsletter, author, tags, related.
 */

/* ── Article Hero ──────────────────────────────────────────────────── */
.k-single-hero {
  position: relative;
  width: 100%;
  height: 480px;
  display: flex;
  align-items: flex-end;
  overflow: hidden;
}

.k-single-hero__img {
  position: absolute;
  inset: 0;
  background-size: cover;
  background-position: center;
  filter: grayscale(1) contrast(1.2);
  width: 100%;
  height: 100%;
}

.k-single-hero__gradient {
  position: absolute;
  inset: 0;
  background: linear-gradient(to top, var(--k-background) 0%, rgba(10, 10, 15, 0.8) 50%, transparent 100%);
}

.k-single-hero__content {
  position: relative;
  z-index: 10;
  width: 100%;
  max-width: 1440px;
  margin-inline: auto;
  padding: 0 2.5rem 2.5rem;
}

@media (min-width: 1024px) {
  .k-single-hero__content { padding: 0 3rem 3rem; }
}

.k-single-hero__breadcrumb {
  display: flex;
  align-items: center;
  gap: 0.25rem;
  font-family: 'Space Grotesk', sans-serif;
  font-size: 0.6875rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--k-muted);
  margin-bottom: 1rem;
}

.k-single-hero__breadcrumb a { color: var(--k-muted); text-decoration: none; }
.k-single-hero__breadcrumb a:hover { color: var(--k-text); }
.k-single-hero__breadcrumb-sep {
  width: 14px;
  height: 14px;
  opacity: 0.5;
}
.k-single-hero__breadcrumb-current { color: var(--k-cyan); }

.k-single-hero__title {
  font-family: 'Space Grotesk', sans-serif;
  font-size: clamp(2rem, 4vw, 3.5rem);
  font-weight: 700;
  line-height: 1.1;
  letter-spacing: -0.02em;
  color: var(--k-text);
  max-width: 54rem;
  margin: 0 0 1.25rem;
}

.k-single-hero__badges {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin-bottom: 1.5rem;
  flex-wrap: wrap;
}

.k-single-hero__badge {
  display: inline-flex;
  align-items: center;
  gap: 0.375rem;
  padding: 0.25rem 0.75rem;
  font-family: 'Space Grotesk', sans-serif;
  font-size: 0.6875rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  border-radius: 0.25rem;
}

.k-single-hero__badge--cat {
  background: var(--k-surface);
  color: var(--k-cyan);
}

.k-single-hero__badge--time {
  background: var(--k-green);
  color: #003919;
}

.k-single-hero__meta-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-top: 1px solid rgba(255, 255, 255, 0.06);
  padding-top: 1rem;
  flex-wrap: wrap;
  gap: 1rem;
}

.k-single-hero__author {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.k-single-hero__avatar {
  width: 3rem;
  height: 3rem;
  border-radius: 50%;
  object-fit: cover;
  filter: grayscale(1) contrast(1.2);
  border: 2px solid var(--k-cyan);
  flex-shrink: 0;
}

.k-single-hero__author-name {
  font-family: 'Space Grotesk', sans-serif;
  font-size: 1rem;
  font-weight: 600;
  color: var(--k-text);
  display: block;
}

.k-single-hero__author-date {
  font-family: 'Space Grotesk', sans-serif;
  font-size: 0.6875rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--k-muted);
  display: block;
  margin-top: 0.125rem;
}

.k-single-hero__actions {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.k-single-hero__action-btn {
  background: none;
  border: none;
  color: var(--k-muted);
  cursor: pointer;
  padding: 0.375rem;
  border-radius: 0.375rem;
  transition: color 0.2s, background 0.2s;
  display: flex;
  align-items: center;
}

.k-single-hero__action-btn:hover {
  color: var(--k-cyan);
  background: rgba(0, 212, 255, 0.08);
}

/* ── Layout ────────────────────────────────────────────────────────── */
.k-single-layout {
  background: var(--k-background);
  padding: 2.5rem 0 4rem;
}

.k-single-layout__inner {
  max-width: 1440px;
  margin-inline: auto;
  padding-inline: 2.5rem;
  display: grid;
  grid-template-columns: 1fr;
  gap: 2rem;
}

@media (min-width: 1024px) {
  .k-single-layout__inner {
    grid-template-columns: 1fr 340px;
    align-items: start;
    padding-inline: 3rem;
  }
}

/* ── Article shell ─────────────────────────────────────────────────── */
.k-single-article {
  background: var(--k-surface);
  padding: 2.5rem;
  border-radius: 0.5rem;
  min-width: 0;
}

/* ── Sidebar ───────────────────────────────────────────────────────── */
.k-single-sidebar {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

@media (min-width: 1024px) {
  .k-single-sidebar { position: sticky; top: 5.5rem; }
}

/* ── TOC ───────────────────────────────────────────────────────────── */
.k-single-toc {
  background: var(--k-surface);
  padding: 1.25rem;
  border-radius: 0.5rem;
}

.k-single-toc__title {
  font-family: 'Space Grotesk', sans-serif;
  font-size: 0.6875rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--k-text);
  margin: 0 0 1rem;
  padding-bottom: 0.75rem;
  border-bottom: 1px solid var(--k-hairline);
}

.k-single-toc__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
}

.k-single-toc__link {
  display: block;
  font-family: 'Inter', sans-serif;
  font-size: 0.9375rem;
  color: var(--k-muted);
  text-decoration: none;
  padding: 0.25rem 0 0.25rem 0.75rem;
  border-left: 2px solid transparent;
  transition: color 0.2s, border-color 0.2s;
  line-height: 1.4;
}

.k-single-toc__link:hover {
  color: var(--k-text);
}

.k-single-toc__link--h3 {
  font-size: 0.8125rem;
  padding-left: 1.5rem;
}

.k-single-toc__link--active {
  color: var(--k-cyan);
  border-left-color: var(--k-cyan);
}

/* ── Newsletter (sidebar) ──────────────────────────────────────────── */
.k-single-newsletter {
  background: rgba(var(--k-glass-rgb), 0.6);
  backdrop-filter: blur(24px);
  -webkit-backdrop-filter: blur(24px);
  padding: 1.5rem;
  border-radius: 0.5rem;
  border: 1px solid var(--k-hairline);
  position: relative;
  overflow: hidden;
}

.k-single-newsletter__glow {
  position: absolute;
  top: -2.5rem;
  right: -2.5rem;
  width: 8rem;
  height: 8rem;
  background: rgba(0, 212, 255, 0.1);
  border-radius: 50%;
  filter: blur(3rem);
  pointer-events: none;
}

.k-single-newsletter__title {
  font-family: 'Space Grotesk', sans-serif;
  font-size: 1.375rem;
  font-weight: 700;
  color: var(--k-text);
  margin: 0 0 0.375rem;
  position: relative;
}

.k-single-newsletter__desc {
  font-family: 'Inter', sans-serif;
  font-size: 0.875rem;
  color: var(--k-muted);
  margin: 0 0 1.25rem;
  line-height: 1.5;
  position: relative;
}

.k-single-newsletter__form {
  display: flex;
  flex-direction: column;
  gap: 0.625rem;
  position: relative;
}

.k-single-newsletter__input {
  background: var(--k-background);
  border: none;
  border-bottom: 2px solid transparent;
  padding: 0.75rem 1rem;
  font-family: 'Inter', sans-serif;
  font-size: 0.9375rem;
  color: var(--k-text);
  outline: none;
  width: 100%;
  transition: border-color 0.2s;
}

.k-single-newsletter__input::placeholder { color: rgba(139, 139, 158, 0.5); }
.k-single-newsletter__input:focus { border-bottom-color: var(--k-cyan); }

.k-single-newsletter__btn {
  width: 100%;
  padding: 0.75rem;
  background: var(--k-cyan);
  color: #000;
  font-family: 'Space Grotesk', sans-serif;
  font-size: 0.875rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  border: none;
  cursor: pointer;
  transition: background 0.2s;
}

.k-single-newsletter__btn:hover { background: #3cd7ff; }

/* ── Author Bio ────────────────────────────────────────────────────── */
.k-single-author {
  display: flex;
  align-items: flex-start;
  gap: 1.25rem;
  background: var(--k-surface-2);
  padding: 1.5rem;
  border-radius: 0.5rem;
  margin-top: 3rem;
}

.k-single-author__avatar-wrap { flex-shrink: 0; }

.k-single-author__avatar {
  width: 4rem;
  height: 4rem;
  border-radius: 50%;
  object-fit: cover;
  filter: grayscale(1);
  border: 2px solid var(--k-cyan);
  display: block;
}

.k-single-author__avatar-placeholder {
  width: 4rem;
  height: 4rem;
  border-radius: 50%;
  background: var(--k-surface);
  border: 2px solid var(--k-cyan);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--k-muted);
}

.k-single-author__name {
  font-family: 'Space Grotesk', sans-serif;
  font-size: 1.0625rem;
  font-weight: 600;
  color: var(--k-text);
  margin: 0 0 0.125rem;
}

.k-single-author__role {
  font-family: 'Space Grotesk', sans-serif;
  font-size: 0.6875rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--k-muted);
  margin: 0 0 0.75rem;
  display: block;
}

.k-single-author__bio {
  font-family: 'Inter', sans-serif;
  font-size: 0.9375rem;
  color: var(--k-muted);
  line-height: 1.6;
  margin: 0 0 0.75rem;
}

.k-single-author__link {
  display: inline-flex;
  align-items: center;
  gap: 0.375rem;
  font-family: 'Space Grotesk', sans-serif;
  font-size: 0.6875rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--k-cyan);
  text-decoration: none;
  transition: gap 0.2s;
}

.k-single-author__link:hover { gap: 0.625rem; }

/* ── Tags bar ──────────────────────────────────────────────────────── */
.k-single-tags {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 1rem;
  margin-top: 1.5rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--k-hairline);
}

.k-single-tags__label {
  font-family: 'Space Grotesk', sans-serif;
  font-size: 0.6875rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--k-muted);
  margin-right: 0.5rem;
}

.k-single-tags__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.5rem;
}

.k-single-tag {
  padding: 0.25rem 0.625rem;
  background: var(--k-surface-2);
  color: var(--k-muted);
  font-family: 'Space Grotesk', sans-serif;
  font-size: 0.625rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  text-decoration: none;
  border-radius: 0.25rem;
  transition: background 0.2s, color 0.2s;
}

.k-single-tag:hover { background: var(--k-violet); color: #fff; }

.k-single-share {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.k-single-share__btn {
  width: 2rem;
  height: 2rem;
  border-radius: 0.375rem;
  background: var(--k-surface-2);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--k-muted);
  text-decoration: none;
  transition: background 0.2s, color 0.2s;
  border: none;
  cursor: pointer;
}

.k-single-share__btn:hover { background: var(--k-cyan); color: #003642; }

/* ── Related Articles ──────────────────────────────────────────────── */
.k-single-related {
  background: var(--k-background);
  padding: 4rem 0;
}

.k-single-related__inner {
  max-width: 1440px;
  margin-inline: auto;
  padding-inline: 2.5rem;
}

@media (min-width: 1024px) {
  .k-single-related__inner { padding-inline: 3rem; }
}

.k-single-related__header {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin-bottom: 2rem;
}

.k-single-related__accent {
  display: block;
  width: 1rem;
  height: 3px;
  background: var(--k-cyan);
  border-radius: 9999px;
  flex-shrink: 0;
}

.k-single-related__title {
  font-family: 'Space Grotesk', sans-serif;
  font-size: 0.6875rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--k-text);
  margin: 0;
}

.k-single-related__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.5rem;
}

@media (min-width: 640px) {
  .k-single-related__grid { grid-template-columns: repeat(2, 1fr); }
}

@media (min-width: 1024px) {
  .k-single-related__grid { grid-template-columns: repeat(3, 1fr); }
}