/* ==========================================================================
   article.css — প্রিমিয়াম লং-ফর্ম আর্টিকেল পেজের জন্য।
   style.css এর কালার/ফন্ট টোকেন ব্যবহার করে বানানো, যাতে পুরো সাইটের সাথে
   ডিজাইন মিলে যায়। ভবিষ্যতে নতুন আর্টিকেল বানালে এই একই ফাইল ব্যবহার করা যাবে।
   ========================================================================== */

/* ---------------- রিডিং প্রোগ্রেস বার ---------------- */
.reading-progress{
  position: fixed; top:0; left:0; right:0; height: 4px;
  background: rgba(0,0,0,.08); z-index: 60;
}
.reading-progress-fill{
  height: 100%; width: 0%;
  background: linear-gradient(90deg, var(--teal), var(--gold));
  transition: width .1s linear;
}

/* ---------------- হিরো সেকশন ---------------- */
.article-hero{
  background: linear-gradient(160deg, var(--ink) 0%, var(--ink-2) 100%);
  padding: 3.6rem 1.4rem 3rem;
  text-align:center;
}
.article-hero-inner{ max-width: 780px; margin:0 auto; }
.article-tag{
  display:inline-block; font-family: var(--font-util); font-size:.75rem;
  letter-spacing:.1em; font-weight:700; color: var(--ink);
  background: var(--gold); padding:.35rem .9rem; border-radius:999px;
  margin-bottom: 1.2rem;
}
.article-title{
  color:#fff; font-size: clamp(1.7rem, 4.5vw, 2.6rem); line-height:1.3;
  margin: 0 0 1rem;
}
.article-dek{
  color: rgba(255,255,255,.82); font-size: 1.05rem; line-height:1.8;
  max-width: 640px; margin: 0 auto 1.4rem;
}
.article-meta{
  display:flex; justify-content:center; flex-wrap:wrap; gap:.5rem;
  color: var(--gold); font-family: var(--font-util); font-size:.85rem; font-weight:600;
}

/* ---------------- আর্টিকেল বডি ---------------- */
.article-body{
  max-width: 740px; margin: 0 auto; padding: 3rem 1.4rem 2rem;
  color: var(--charcoal); font-size: 1.05rem; line-height: 1.95;
}
.article-body h2{
  font-size: clamp(1.3rem, 3vw, 1.65rem); margin: 2.4rem 0 1rem;
  color: var(--ink); border-bottom: 2px solid var(--line); padding-bottom: .5rem;
}
.article-body p{ margin: 0 0 1.2rem; }
.article-body strong{ color: var(--ink); }
.lead-para{ font-size: 1.15rem; color: var(--ink); font-weight:500; }
.article-list{ padding-left: 1.3rem; margin: 0 0 1.4rem; }
.article-list li{ margin-bottom: .6rem; }
code{
  background: var(--paper-2); padding: .15rem .4rem; border-radius:5px;
  font-family: 'Courier New', monospace; font-size: .92rem; color: var(--teal-dark);
}

/* ---------------- কোড ব্লক ---------------- */
.code-block{
  background: #1B2029; border-radius: 12px; overflow:hidden; margin: 1.4rem 0;
  box-shadow: var(--shadow);
}
.code-block-label{
  font-family: var(--font-util); font-size:.72rem; letter-spacing:.08em;
  color: var(--gold); background: rgba(255,255,255,.06);
  padding: .5rem 1rem; text-transform: uppercase; font-weight:700;
}
.code-block pre{ margin:0; padding: 1.1rem 1.2rem; overflow-x:auto; }
.code-block code{
  background:none; color: #E8E6DD; font-size: .9rem; line-height:1.7; padding:0;
}

/* ---------------- কলআউট বক্স ---------------- */
.callout{
  display:flex; gap: .9rem; align-items:flex-start;
  border-radius: 12px; padding: 1.2rem 1.4rem; margin: 1.6rem 0;
  border-left: 5px solid var(--teal);
  background: var(--card-bg);
}
.callout-icon{ font-size: 1.4rem; line-height:1; }
.callout-icon svg{ width:1.4rem; height:1.4rem; display:block; fill:none; stroke:currentColor; stroke-width:1.8; stroke-linecap:round; stroke-linejoin:round; }
.article-tag svg{ width:1em; height:1em; display:inline-block; vertical-align:-0.15em; margin-right:.3rem; fill:none; stroke:currentColor; stroke-width:2; stroke-linecap:round; stroke-linejoin:round; }
.callout p{ margin:0; }
.callout-quote{
  border-left-color: var(--gold);
  font-family: var(--font-display); font-style: italic; color: var(--ink);
  flex-direction: column; gap:.5rem;
}
.callout-quote p{ font-size: 1.15rem; margin:0; }
.callout-source{ font-family: var(--font-util); font-style:normal; font-size:.82rem; color: var(--muted); }
.callout-tip{ border-left-color: #3B82F6; }
.callout-info{ border-left-color: var(--teal); }

/* ---------------- একাধিক গল্প — অ্যাকর্ডিয়ন লিস্ট (nasir.html/nazim.html/...) ---------------- */
.story-list{ display:flex; flex-direction:column; gap: .9rem; margin: 1.8rem 0; }
.story-item{
  background: var(--card-bg); border: 1px solid var(--line); border-radius: 14px;
  overflow: hidden; box-shadow: var(--shadow);
}
.story-summary{
  list-style:none; cursor:pointer; display:flex; align-items:center; gap:.8rem;
  padding: 1rem 1.3rem; font-family: var(--font-display); font-weight:700;
  font-size: 1.05rem; color:#10182B; -webkit-text-fill-color:#10182B;
}
.story-summary::-webkit-details-marker{ display:none; }
.story-summary::marker{ content:""; }
.story-num{
  flex:0 0 auto; color: var(--gold); font-weight:800; min-width: 1.6rem;
}
.story-title-text{ flex:1 1 auto; }
.story-chevron{
  flex:0 0 auto; color: var(--muted); transition: transform .2s var(--ease);
}
.story-item[open] .story-chevron{ transform: rotate(180deg); }
.story-content{
  padding: .2rem 1.3rem 1.5rem; border-top: 1px solid var(--line);
  color: var(--charcoal); font-size: 1.02rem; line-height: 1.9;
}
.story-content p{ margin: 1.1rem 0 0; }
.story-content .article-meta{ margin: 1rem 0 0; }

/* ---------------- সামারি কার্ড গ্রিড ---------------- */
.summary-grid{
  display:grid; grid-template-columns: repeat(auto-fit, minmax(200px,1fr)); gap: 1rem;
  margin: 1.6rem 0 2rem;
}
.summary-card{
  background: var(--card-bg); border: 1px solid var(--line); border-radius: 14px;
  padding: 1.2rem; box-shadow: var(--shadow);
}
.summary-icon{ font-size: 1.6rem; margin-bottom:.5rem; }
.summary-card h4{ font-family: var(--font-display); color: var(--ink); font-size: 1rem; margin:0 0 .4rem; }
.summary-card p{ font-size: .88rem; color: var(--muted); margin:0; }

/* ---------------- রোডম্যাপ ---------------- */
.roadmap{ position: relative; margin: 1.6rem 0 2rem; padding-left: 2.2rem; }
.roadmap::before{
  content:""; position:absolute; left: 17px; top: 6px; bottom: 6px; width: 2px;
  background: repeating-linear-gradient(to bottom, var(--gold) 0 6px, transparent 6px 12px);
}
.roadmap-step{ position: relative; margin-bottom: 1.8rem; }
.roadmap-num{
  position:absolute; left: -2.2rem; top:0;
  width: 36px; height:36px; border-radius:50%;
  background: var(--teal); color:#fff; font-family: var(--font-display); font-weight:700;
  display:flex; align-items:center; justify-content:center; font-size:1rem;
  box-shadow: 0 4px 10px rgba(14,110,92,.35);
}
.roadmap-content h4{ font-family: var(--font-display); color: var(--ink); margin: 0 0 .4rem; font-size: 1.08rem; }
.roadmap-content p{ margin:0; color: var(--charcoal); font-size: .96rem; }

/* ---------------- FAQ (accordion, native details/summary) ---------------- */
.faq-list{ margin: 1.4rem 0 2rem; }
.faq-item{
  background: var(--card-bg); border: 1px solid var(--line); border-radius: 12px;
  padding: .95rem 1.2rem; margin-bottom: .8rem;
}
.faq-item summary{
  cursor:pointer; font-weight:700; color: var(--ink); font-family: var(--font-body);
  list-style: none; display:flex; justify-content:space-between; align-items:center; gap: 1rem;
}
.faq-item summary::-webkit-details-marker{ display:none; }
.faq-item summary::after{ content:"+"; font-size:1.3rem; color: var(--teal); flex-shrink:0; }
.faq-item[open] summary::after{ content:"–"; }
.faq-item p{ margin: .8rem 0 0; color: var(--charcoal); font-size: .95rem; }

/* ---------------- কী-টেকওয়ে কার্ড ---------------- */
.takeaway-card{
  background: linear-gradient(155deg, var(--ink), var(--ink-2));
  color:#fff; border-radius: 16px; padding: 1.6rem 1.8rem; margin: 1.6rem 0;
}
.takeaway-card h4{ font-family: var(--font-display); color: var(--gold); margin:0 0 .8rem; font-size:1.15rem; }
.takeaway-card ul{ margin:0; padding-left: 1.2rem; }
.takeaway-card li{ margin-bottom: .6rem; line-height:1.6; }

.signature-line{ text-align:right; color: var(--muted); font-style: italic; margin-top: 2rem; }

/* ---------------- আর্টিকেল নেভিগেশন (Back / Prev / Next) ---------------- */
.article-nav-section{
  max-width: 900px; margin: 1rem auto 3rem; padding: 0 1.4rem;
  display:flex; flex-direction:column; gap: 1.2rem; align-items:flex-start;
}
.prev-next-row{ display:flex; gap: 1rem; width:100%; flex-wrap:wrap; }
.prev-next-card{
  flex: 1 1 260px; background: var(--card-bg); border: 1px solid var(--line);
  border-radius: 14px; padding: 1rem 1.2rem; box-shadow: var(--shadow);
  display:flex; flex-direction:column; gap:.3rem; transition: transform .15s;
}
.prev-next-card:hover{ transform: translateY(-2px); }
.prev-next-card.align-right{ text-align:right; align-items:flex-end; }
.pn-label{ font-family: var(--font-util); font-size:.72rem; letter-spacing:.06em; color: var(--gold); font-weight:700; text-transform:uppercase; }
.pn-title{ font-family: var(--font-display); color: var(--ink); font-size: .98rem; }

/* ---------------- রেসপন্সিভ ---------------- */
@media (max-width: 620px){
  .article-body{ font-size: 1rem; padding: 2.2rem 1.1rem 1.5rem; }
  .article-hero{ padding: 2.6rem 1.1rem 2.2rem; }
  .callout{ flex-direction: column; }
  .roadmap{ padding-left: 1.8rem; }
  .roadmap-num{ left: -1.8rem; width:30px; height:30px; font-size:.85rem; }
}

/* ==========================================================================
   নিচের ক্লাসগুলো নতুন — কোনো পুরনো ক্লাস বদলানো হয়নি, তাই আগের আর্টিকেল
   (ai-programming.html সহ) ভাঙার কোনো ঝুঁকি নেই।
   ========================================================================== */

/* ---------------- Author Card ---------------- */
.author-card{
  display:flex; align-items:center; gap: .9rem; max-width: 780px; margin: 0 auto 2.2rem;
  padding: 1rem 1.3rem; background: var(--card-bg); border: 1px solid var(--line);
  border-radius: 14px; box-shadow: var(--shadow);
}
.author-avatar{
  width: 46px; height:46px; border-radius:50%; object-fit:cover; flex-shrink:0;
  border: 2px solid var(--gold);
}
.author-name{ font-family: var(--font-display); color: var(--ink); font-weight:700; font-size: .96rem; }
.author-role{ color: var(--muted); font-size: .82rem; }

/* ---------------- Table of Contents ---------------- */
.article-toc{
  max-width: 780px; margin: 0 auto 2rem; background: var(--card-bg);
  border: 1px solid var(--line); border-radius: 14px; padding: 1.2rem 1.4rem;
  box-shadow: var(--shadow); position: static !important; top: auto !important; z-index: auto !important;
}
.article-toc h5{
  font-family: var(--font-util); font-size:.72rem; letter-spacing:.1em; text-transform:uppercase;
  color: var(--gold); margin: 0 0 .7rem; font-weight:700;
}
.article-toc ol{ margin:0; padding-left: 1.1rem; }
.article-toc li{ margin-bottom: .4rem; }
.article-toc a{ color: var(--ink); font-size: .9rem; font-weight:600; text-decoration:none; }
.article-toc a:hover{ color: var(--teal); }

/* ---------------- শেয়ার / কপি লিংক ---------------- */
.share-row{
  display:flex; gap: .6rem; flex-wrap:wrap; justify-content:center;
  max-width: 780px; margin: 2.2rem auto; padding-top: 1.6rem; border-top: 1px solid var(--line);
}
.share-btn{
  display:inline-flex; align-items:center; gap:.4rem; padding: .6rem 1.1rem;
  border-radius: 999px; border: 1.5px solid var(--line); background: var(--card-bg);
  color: var(--ink); font-size:.85rem; font-weight:600; cursor:pointer; font-family: var(--font-body);
  text-decoration:none; transition: all .18s ease;
}
.share-btn:hover{ background: var(--teal); color:#fff; border-color: var(--teal); }

/* ---------------- চেকলিস্ট ---------------- */
.checklist-box{
  background: var(--card-bg); border: 1px solid var(--line); border-radius: 14px;
  padding: 1.3rem 1.5rem; margin: 1.6rem 0;
}
.checklist-item{
  display:flex; align-items:flex-start; gap:.7rem; padding: .55rem 0;
  border-bottom: 1px solid var(--line); font-size: .96rem;
}
.checklist-item:last-child{ border-bottom:none; }
.checklist-item input[type=checkbox]{ width:19px; height:19px; margin-top:2px; accent-color: var(--teal); flex-shrink:0; }

/* ---------------- উপসংহার কার্ড ---------------- */
.conclusion-card{
  background: linear-gradient(150deg, var(--teal), var(--teal-dark)); color:#fff;
  border-radius: 16px; padding: 1.8rem 2rem; margin: 2rem 0; text-align:center;
}
.conclusion-card p{ margin:0; font-size: 1.02rem; line-height:1.85; }

/* ---------------- ফুটার কোট ---------------- */
.footer-quote-block{
  text-align:center; padding: 2.6rem 1.4rem; background: var(--ink); color: var(--gold);
  font-family: var(--font-display); font-size: 1.1rem; line-height:1.85;
}