/* ============================================================
   KKRF TECH — Blog Single / Article Page
   ============================================================ */

/* ---- Reading Progress ---- */
.read-progress {
  position: fixed; top: 0; left: 0; right: 0; z-index: 1000;
  height: 3px; background: transparent; pointer-events: none;
}
.read-progress__bar {
  height: 100%; width: 0;
  background: linear-gradient(90deg, var(--blue), #4a90ff);
  transition: width .1s linear;
}

/* ---- Article Hero ---- */
.art-hero {
  background: var(--black);
  padding: 140px 0 80px;
  position: relative; overflow: hidden;
}
.art-hero::before {
  content: "";
  position: absolute; top: -200px; left: -150px;
  width: 700px; height: 700px; border-radius: 50%;
  background: radial-gradient(circle, rgba(21,116,255,.13), transparent 65%);
  pointer-events: none;
}
.art-hero::after {
  content: "";
  position: absolute; inset: 0;
  background-image: radial-gradient(circle at 1px 1px, rgba(255,255,255,.04) 1px, transparent 0);
  background-size: 32px 32px;
  pointer-events: none;
}
.art-hero__inner { position: relative; z-index: 1; max-width: 860px; }

.art-hero__breadcrumb {
  display: flex; align-items: center; gap: 8px;
  font-size: 13px; color: rgba(255,255,255,.4);
  margin-bottom: 24px;
  font-family: 'Inter', sans-serif; letter-spacing: .04em;
}
.art-hero__breadcrumb a { color: rgba(255,255,255,.5); text-decoration: none; transition: color .2s; }
.art-hero__breadcrumb a:hover { color: var(--white); }

.art-hero__meta-top {
  display: flex; align-items: center; gap: 16px; margin-bottom: 24px;
}
.art-cat {
  display: inline-block;
  font-size: 11px; font-weight: 700; letter-spacing: .12em; text-transform: uppercase;
  color: var(--blue); background: rgba(21,116,255,.15);
  padding: 4px 14px; border-radius: 999px;
  border: 1px solid rgba(21,116,255,.3);
}
.art-hero__reading {
  font-family: 'Inter', sans-serif; font-size: 12px; color: rgba(255,255,255,.4);
  letter-spacing: .06em;
}

.art-hero__title {
  font-family: var(--font-display);
  font-size: clamp(28px, 4vw, 52px); font-weight: 800; letter-spacing: -.04em;
  color: var(--white); line-height: 1.08; margin-bottom: 24px;
}
.art-hero__sub {
  font-size: clamp(15px, 1.3vw, 18px); line-height: 1.65;
  color: rgba(255,255,255,.55); max-width: 680px; margin-bottom: 40px;
}
.art-hero__author {
  display: flex; align-items: center; gap: 14px;
  padding-top: 32px;
  border-top: 1px solid rgba(255,255,255,.1);
}
.art-author-avatar {
  width: 42px; height: 42px; border-radius: 50%;
  background: rgba(21,116,255,.2); border: 1px solid rgba(21,116,255,.3);
  display: flex; align-items: center; justify-content: center; flex-shrink: 0;
}
.art-author-avatar svg { width: 20px; height: 20px; stroke: rgba(255,255,255,.6); }
.art-author-name { font-size: 14px; font-weight: 600; color: var(--white); }
.art-author-date { font-size: 12px; color: rgba(255,255,255,.4); margin-top: 2px; font-family: 'Inter', sans-serif; }

/* ---- Cover Image ---- */
.art-cover {
  background: #fff;
}
.art-cover__img {
  max-width: 1200px; margin: 0 auto;
  height: clamp(280px, 35vw, 500px);
  background: linear-gradient(135deg, #0a2448 0%, #1574FF 100%);
  display: flex; align-items: center; justify-content: center;
  position: relative; overflow: hidden;
}
.art-cover__img::before {
  content: "";
  position: absolute; inset: 0;
  background-image: radial-gradient(circle at 1px 1px, rgba(255,255,255,.06) 1px, transparent 0);
  background-size: 24px 24px;
}
.art-cover__text {
  position: relative; z-index: 1;
  font-family: var(--font-display);
  font-size: clamp(32px, 4vw, 56px); font-weight: 900; letter-spacing: -.04em;
  color: rgba(255,255,255,.85); text-align: center; line-height: 1.1;
}

/* ---- Article Body Layout ---- */
.art-body-wrap {
  background: var(--white);
  padding: clamp(60px, 8vw, 100px) 0;
}
.art-body-layout {
  display: grid;
  grid-template-columns: 220px 1fr 320px;
  gap: 56px;
  align-items: start;
}

/* ---- Table of Contents ---- */
.art-toc {
  position: sticky; top: 100px;
}
.art-toc__label {
  font-family: 'Inter', sans-serif; font-size: 10px; font-weight: 500;
  letter-spacing: .16em; text-transform: uppercase; color: var(--g-500);
  margin-bottom: 16px;
}
.art-toc nav { display: flex; flex-direction: column; gap: 2px; }
.art-toc__link {
  display: block; padding: 7px 12px;
  font-size: 13px; line-height: 1.4;
  color: var(--g-500); text-decoration: none;
  border-left: 2px solid var(--line);
  transition: color .2s, border-color .2s, background .2s;
  border-radius: 0 4px 4px 0;
}
.art-toc__link:hover { color: var(--blue); border-color: var(--blue-tint-2); }
.art-toc__link.active { color: var(--blue); border-color: var(--blue); background: var(--blue-tint); font-weight: 600; }

.art-toc__share { margin-top: 32px; padding-top: 24px; border-top: 1px solid var(--line); }
.art-toc__share p { font-size: 11px; color: var(--g-500); font-family: 'Inter', sans-serif; letter-spacing: .1em; text-transform: uppercase; margin-bottom: 12px; }
.art-toc__share-btns { display: flex; gap: 8px; }
.art-share-btn {
  width: 36px; height: 36px; border-radius: 8px;
  border: 1px solid var(--line); background: var(--white);
  display: flex; align-items: center; justify-content: center;
  cursor: pointer; color: var(--g-500);
  transition: all .2s;
}
.art-share-btn svg { width: 15px; height: 15px; }
.art-share-btn:hover { border-color: var(--blue); color: var(--blue); background: var(--blue-tint); }

/* ---- Article Content ---- */
.art-body {
  max-width: 720px;
}
.art-body section { margin-bottom: 56px; }
.art-body h2 {
  font-family: var(--font-display);
  font-size: clamp(22px, 2.2vw, 30px); font-weight: 700; letter-spacing: -.03em;
  color: var(--ink); margin-bottom: 20px; margin-top: 8px; line-height: 1.2;
}
.art-lead {
  font-size: clamp(17px, 1.3vw, 20px); line-height: 1.65;
  color: var(--ink); font-weight: 500; margin-bottom: 20px;
}
.art-body p {
  font-size: 16px; line-height: 1.8; color: var(--g-700); margin-bottom: 20px;
}
.art-body p:last-child { margin-bottom: 0; }
.art-body ul.art-ul {
  list-style: none; margin: 0 0 20px; padding: 0;
  display: flex; flex-direction: column; gap: 12px;
}
.art-body ul.art-ul li {
  font-size: 16px; line-height: 1.7; color: var(--g-700);
  padding-left: 24px; position: relative;
}
.art-body ul.art-ul li::before {
  content: "—"; position: absolute; left: 0; color: var(--blue); font-weight: 700;
}

/* ---- Callout ---- */
.art-callout {
  display: flex; gap: 18px;
  background: var(--paper);
  border: 1px solid var(--line);
  border-left: 3px solid var(--ink);
  border-radius: 0 12px 12px 0;
  padding: 24px 24px;
  margin: 28px 0;
}
.art-callout--blue { border-left-color: var(--blue); background: var(--blue-tint); border-color: var(--blue-tint-2); }
.art-callout__icon {
  width: 36px; height: 36px; flex-shrink: 0;
  display: flex; align-items: center; justify-content: center;
  background: var(--white); border: 1px solid var(--line);
  border-radius: 8px; color: var(--g-600);
}
.art-callout--blue .art-callout__icon { background: rgba(21,116,255,.1); border-color: var(--blue-tint-2); color: var(--blue); }
.art-callout__icon svg { width: 18px; height: 18px; }
.art-callout strong { display: block; font-size: 13px; font-weight: 700; color: var(--ink); margin-bottom: 6px; letter-spacing: .03em; text-transform: uppercase; font-family: var(--font-display); }
.art-callout p { font-size: 14.5px; line-height: 1.65; color: var(--g-600); margin: 0; }

/* ---- Blockquote ---- */
.art-quote {
  border-left: 3px solid var(--blue);
  padding: 12px 28px; margin: 32px 0;
}
.art-quote blockquote {
  font-family: var(--font-display);
  font-size: clamp(17px, 1.6vw, 22px); font-weight: 600; letter-spacing: -.02em;
  color: var(--ink); line-height: 1.5; margin-bottom: 12px;
}
.art-quote cite {
  font-size: 13px; color: var(--g-500); font-style: normal;
  font-family: 'Inter', sans-serif;
}

/* ---- Numbered list ---- */
.art-list { margin: 28px 0; display: flex; flex-direction: column; gap: 20px; }
.art-list__item {
  display: flex; gap: 20px; align-items: flex-start;
  padding: 20px 24px;
  background: var(--paper); border: 1px solid var(--line); border-radius: 14px;
}
.art-list__no {
  font-family: 'Inter', sans-serif; font-size: 11px; font-weight: 700;
  color: var(--blue); min-width: 24px; padding-top: 3px; letter-spacing: .06em;
}
.art-list__item strong { display: block; font-size: 15px; font-weight: 700; color: var(--ink); margin-bottom: 6px; letter-spacing: -.01em; }
.art-list__item p { font-size: 14px; line-height: 1.65; color: var(--g-600); margin: 0; }

/* ---- Takeaways ---- */
.art-takeaways { display: flex; flex-direction: column; gap: 16px; margin-top: 24px; }
.art-takeaway {
  display: flex; gap: 20px; align-items: flex-start;
  padding: 22px 24px;
  border: 1px solid var(--line); border-radius: 14px;
  transition: border-color .3s, box-shadow .3s;
}
.art-takeaway:hover { border-color: var(--blue-tint-2); box-shadow: 0 4px 24px rgba(21,116,255,.06); }
.art-takeaway__no {
  font-family: 'Inter', sans-serif; font-size: 12px; font-weight: 700;
  color: var(--blue); min-width: 24px; padding-top: 2px;
}
.art-takeaway strong { display: block; font-size: 15px; font-weight: 700; color: var(--ink); margin-bottom: 5px; }
.art-takeaway div { font-size: 14.5px; line-height: 1.65; color: var(--g-600); }

/* ---- Tags ---- */
.art-tags {
  display: flex; flex-wrap: wrap; gap: 8px;
  margin-top: 48px; padding-top: 36px;
  border-top: 1px solid var(--line);
}
.art-tag {
  padding: 6px 14px;
  border: 1px solid var(--line); border-radius: 999px;
  font-size: 12px; font-weight: 600; color: var(--g-600);
  font-family: var(--font-display);
  transition: all .2s;
  cursor: default;
}
.art-tag:hover { border-color: var(--blue); color: var(--blue); background: var(--blue-tint); }

/* ---- Author Card ---- */
.art-author-card {
  display: flex; gap: 24px; align-items: flex-start;
  background: var(--paper); border: 1px solid var(--line);
  border-radius: 18px; padding: 32px 28px;
  margin-top: 48px;
}
.art-author-card__avatar {
  width: 60px; height: 60px; flex-shrink: 0; border-radius: 50%;
  background: var(--blue-tint); border: 1.5px solid var(--blue-tint-2);
  display: flex; align-items: center; justify-content: center;
}
.art-author-card__avatar svg { width: 28px; height: 28px; stroke: var(--blue); }
.art-author-card__label {
  font-family: 'Inter', sans-serif; font-size: 10px; font-weight: 500;
  letter-spacing: .14em; text-transform: uppercase; color: var(--g-500); margin-bottom: 4px;
}
.art-author-card h4 { font-family: var(--font-display); font-size: 17px; font-weight: 700; color: var(--ink); margin-bottom: 10px; }
.art-author-card p { font-size: 14px; line-height: 1.65; color: var(--g-600); margin-bottom: 14px; }
.art-author-card__link { font-size: 13px; font-weight: 700; color: var(--blue); text-decoration: none; font-family: var(--font-display); }
.art-author-card__link:hover { text-decoration: underline; }

/* ---- Contact Form Sidebar ---- */
.art-contact-sidebar {
  position: sticky;
  top: 100px;
}
.art-contact-form {
  background: var(--black);
  border-radius: 20px;
  padding: 32px 28px;
  position: relative;
  overflow: hidden;
}
.art-contact-form::before {
  content: "";
  position: absolute; top: -120px; right: -120px;
  width: 300px; height: 300px; border-radius: 50%;
  background: radial-gradient(circle, rgba(21,116,255,.18), transparent 65%);
  pointer-events: none;
}
.art-contact-form::after {
  content: "";
  position: absolute; inset: 0;
  background-image: radial-gradient(circle at 1px 1px, rgba(255,255,255,.035) 1px, transparent 0);
  background-size: 24px 24px;
  pointer-events: none;
}
.art-contact-form__inner { position: relative; z-index: 1; }
.art-contact-form__eyebrow {
  font-family: 'Inter', sans-serif;
  font-size: 10px; font-weight: 500; letter-spacing: .16em; text-transform: uppercase;
  color: var(--blue); display: flex; align-items: center; gap: 8px;
  margin-bottom: 14px;
}
.art-contact-form__eyebrow::before { content: ""; width: 16px; height: 1.5px; background: var(--blue); }
.art-contact-form__title {
  font-family: var(--font-display);
  font-size: 20px; font-weight: 800; letter-spacing: -.03em;
  color: var(--white); line-height: 1.15; margin-bottom: 8px;
}
.art-contact-form__sub {
  font-size: 13px; line-height: 1.6; color: rgba(255,255,255,.45);
  margin-bottom: 24px;
}
.art-contact-form__fields { display: flex; flex-direction: column; gap: 12px; }
.art-cf-field {
  display: flex; flex-direction: column; gap: 6px;
}
.art-cf-field label {
  font-size: 11px; font-weight: 600; letter-spacing: .08em; text-transform: uppercase;
  color: rgba(255,255,255,.4); font-family: var(--font-display);
}
.art-cf-field input,
.art-cf-field select,
.art-cf-field textarea {
  width: 100%;
  background: rgba(255,255,255,.07);
  border: 1px solid rgba(255,255,255,.1);
  border-radius: 10px;
  padding: 11px 14px;
  font-size: 14px; font-family: var(--font-body);
  color: var(--white);
  outline: none;
  transition: border-color .2s, background .2s;
  resize: none;
  -webkit-appearance: none;
}
.art-cf-field input::placeholder,
.art-cf-field textarea::placeholder { color: rgba(255,255,255,.25); }
.art-cf-field input:focus,
.art-cf-field select:focus,
.art-cf-field textarea:focus {
  border-color: rgba(21,116,255,.5);
  background: rgba(21,116,255,.08);
}
.art-cf-field select {
  color: rgba(255,255,255,.6);
  cursor: pointer;
}
.art-cf-field select option { background: #1a1b1e; color: var(--white); }
.art-cf-submit {
  width: 100%; margin-top: 4px;
  background: var(--blue); color: var(--white);
  border: none; border-radius: 10px;
  padding: 13px 20px;
  font-size: 14px; font-weight: 700; font-family: var(--font-display);
  cursor: pointer; letter-spacing: -.01em;
  display: flex; align-items: center; justify-content: center; gap: 8px;
  transition: background .2s, transform .2s, box-shadow .2s;
}
.art-cf-submit:hover {
  background: var(--blue-dark);
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(21,116,255,.35);
}
.art-contact-form__note {
  font-size: 11.5px; color: rgba(255,255,255,.25); text-align: center;
  margin-top: 14px; line-height: 1.5;
}

/* ---- Related Articles ---- */
.art-related {
  background: var(--paper);
  padding: clamp(64px, 8vw, 100px) 0;
  border-top: 1px solid var(--line);
}
.art-related__head {
  margin-bottom: 40px;
}
.art-related__head h2 {
  font-family: var(--font-display); font-size: clamp(24px, 2.8vw, 36px);
  font-weight: 700; letter-spacing: -.03em; color: var(--ink);
  margin-top: 12px;
}
.art-related__grid {
  display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px;
}

/* ---- Responsive ---- */
@media (max-width: 1280px) {
  .art-body-layout { grid-template-columns: 200px 1fr 300px; gap: 40px; }
}
@media (max-width: 1100px) {
  /* hide contact sidebar on tablet and below */
  .art-contact-sidebar { display: none; }
  .art-body-layout { grid-template-columns: 1fr; }
  .art-toc { position: static; display: flex; gap: 40px; align-items: flex-start; flex-wrap: wrap; }
  .art-toc nav { flex-direction: row; flex-wrap: wrap; gap: 4px; }
  .art-toc__link { border-left: none; border-bottom: 2px solid var(--line); border-radius: 0; padding: 4px 8px; }
  .art-toc__link.active { border-bottom-color: var(--blue); border-left: none; background: none; }
  .art-toc__share { margin-top: 0; padding-top: 0; border-top: none; border-left: 1px solid var(--line); padding-left: 32px; }
  .art-related__grid { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 768px) {
  .art-hero { padding: 120px 0 60px; }
  .art-author-card { flex-direction: column; }
  .art-related__grid { grid-template-columns: 1fr; }
  .art-toc { flex-direction: column; }
  .art-toc__share { border-left: none; padding-left: 0; border-top: 1px solid var(--line); padding-top: 20px; margin-top: 0; }
}
@media (max-width: 480px) {
  .blog-hero__stats { flex-direction: column; align-items: flex-start; gap: 16px; }
  .blog-hero__stat-div { display: none; }
}