/* =========================================================
   SHRISTI MITRAA – COURSES PREMIUM BOOK UI
   File: /courses/_core/assets/css/book.css
   FINAL CONSOLIDATED VERSION
========================================================= */

:root{
  --bg:#f6f3ed;
  --bg-soft:#fbfaf7;
  --card:#ffffff;
  --ink:#1f2937;
  --muted:#667085;

  --green:#1f6f4a;
  --green-2:#2e8b57;
  --green-soft:#eaf5ef;

  --earth:#9a6b3d;
  --earth-soft:#fff2e6;

  --blue-soft:#eef5ff;
  --rose-soft:#fff1f2;
  --gold-soft:#fff8e7;

  --line:rgba(17,24,39,.08);
  --shadow:0 18px 45px rgba(15,23,42,.08);
  --shadow-soft:0 10px 28px rgba(15,23,42,.06);

  --radius-xl:26px;
  --radius-lg:20px;
  --radius-md:16px;
  --radius-sm:12px;
}

/* =========================
   Base
========================= */
*{box-sizing:border-box}
html,body{height:100%}
body{
  margin:0;
  font-family:system-ui,-apple-system,"Segoe UI",Roboto,"Noto Sans",Arial,sans-serif;
  color:var(--ink);
  background:
    radial-gradient(circle at top left, rgba(46,139,87,.07), transparent 24%),
    radial-gradient(circle at top right, rgba(154,107,61,.06), transparent 20%),
    linear-gradient(180deg, #f8f6f1 0%, #f2eee7 100%);
  line-height:1.55;
}

.course-wrap a,
.course-wrap a:hover,
.course-wrap a:focus{
  color:inherit;
  text-decoration:none;
}

/* =========================
   Layout
========================= */
.course-main{
  padding:24px 14px 34px;
}
.course-wrap{
  max-width:1180px;
  margin:0 auto;
}

/* =========================
   Topbar
========================= */
.course-topbar{
  position:sticky;
  top:0;
  z-index:50;
  background:rgba(255,255,255,.90);
  backdrop-filter:blur(16px);
  border-bottom:1px solid rgba(17,24,39,.08);
  box-shadow:0 2px 18px rgba(15,23,42,.04);
}

.course-topbar-inner{
  max-width:1120px;
  margin:0 auto;
  padding:10px 14px;
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap:14px;
}

.course-brand{
  display:flex;
  align-items:center;
  gap:10px;
  min-width:0;
}

.course-brand-icn{
  width:42px;
  height:42px;
  border-radius:14px;
  background:linear-gradient(135deg,#eef8f1,#f7fbf8);
  box-shadow:inset 0 0 0 1px rgba(31,111,74,.10);
  overflow:hidden;
  display:grid;
  place-items:center;
  flex:0 0 auto;
}

.course-brand-name{
  font-weight:900;
  line-height:1.05;
  letter-spacing:-.02em;
}

.course-brand-sub{
  font-size:12px;
  color:var(--muted);
  margin-top:2px;
}

.course-nav{
  display:flex;
  align-items:center;
  flex-wrap:wrap;
  gap:10px;
}

.course-navlink{
  padding:9px 14px;
  border-radius:999px;
  background:rgba(255,255,255,.88);
  border:1px solid rgba(17,24,39,.08);
  box-shadow:0 4px 12px rgba(15,23,42,.04);
  font-size:13px;
  font-weight:800;
  transition:.18s ease;
}

.course-navlink:hover{
  transform:translateY(-1px);
  box-shadow:0 8px 18px rgba(0,0,0,.05);
}

.course-navlink.active,
.course-navlink[aria-current="page"]{
  background:linear-gradient(135deg,#edf8f1,#fbfffc);
  border-color:rgba(31,111,74,.18);
  color:var(--green);
}

.course-controls{
  display:flex;
  align-items:center;
  gap:10px;
}

/* =========================
   Hero
========================= */
.sm-book-hero{
  position:relative;
  overflow:hidden;
  padding:34px 34px 30px;
  border-radius:30px;
  background:
    linear-gradient(135deg, rgba(255,255,255,.98), rgba(252,250,246,.95));
  border:1px solid rgba(255,255,255,.55);
  box-shadow:
    0 20px 50px rgba(15,23,42,.07),
    inset 0 1px 0 rgba(255,255,255,.7);
}

.sm-book-hero::before{
  content:"";
  position:absolute;
  top:-80px;
  right:-70px;
  width:240px;
  height:240px;
  border-radius:50%;
  background:radial-gradient(circle, rgba(46,139,87,.12), rgba(46,139,87,0));
  pointer-events:none;
}

.sm-book-hero::after{
  content:"";
  position:absolute;
  bottom:-90px;
  left:-80px;
  width:220px;
  height:220px;
  border-radius:50%;
  background:radial-gradient(circle, rgba(154,107,61,.10), rgba(154,107,61,0));
  pointer-events:none;
}

.sm-hero-chip{
  display:inline-flex;
  align-items:center;
  gap:8px;
  padding:8px 16px;
  border-radius:999px;
  background:linear-gradient(135deg,#ecf8ef,#fafffb);
  color:var(--green);
  font-size:13px;
  font-weight:900;
  border:1px solid rgba(31,111,74,.10);
  box-shadow:0 6px 18px rgba(31,111,74,.05);
}

.sm-hero-title{
  font-size: 30px;
  line-height: 1.15;
  letter-spacing: -.015em;
  margin: 12px 0 8px;
  color: #17212b;
  max-width: 760px;
  font-weight: 900;
}

.sm-hero-sub{
  font-size: 15px;
  line-height: 1.7;
  color: #6b7280;
  max-width: 760px;
  font-weight: 500;
  margin:0;
}

.sm-hero-actions{
  display:flex;
  gap:14px;
  flex-wrap:wrap;
  margin-top:16px !important;
}

.sm-hero-actions .btn{
  padding:12px 18px;
  border-radius:16px;
  font-weight:800;
  box-shadow:0 10px 24px rgba(15,23,42,.06);
}

.sm-hero-tip{
  margin-top:12px !important;
  font-size:14px !important;
  color:#7b8190;
}

/* Hero image elegant frame */
.sm-cover,
.sm-hero-cover{
  display:flex;
  align-items:center;
  justify-content:center;
  min-height:250px;
  padding:12px;
  border-radius:26px;
  background:linear-gradient(180deg,#eef4f0 0%, #f8f5ef 100%);
  box-shadow:
    inset 0 0 0 1px rgba(17,24,39,.05),
    0 10px 24px rgba(15,23,42,.05);
}

.sm-cover img,
.sm-hero-cover img{
  display:block;
  width:auto;
  max-width:100%;
  height:auto !important;
  max-height:225px;
  object-fit:contain !important;
  object-position:center center;
  margin:0 auto;
  border-radius:18px;
  box-shadow:0 10px 24px rgba(15,23,42,.08);
  background:#fff;
}

/* =========================
   Featured course card
========================= */
.sm-course-card{
  display:block;
  padding:26px 26px !important;
  border-radius:28px;
  background:
    linear-gradient(135deg, rgba(255,255,255,.98), rgba(248,253,249,.96));
  box-shadow:
    0 18px 40px rgba(15,23,42,.06),
    inset 0 1px 0 rgba(255,255,255,.65);
  border:1px solid rgba(17,24,39,.05);
  transition:.2s ease;
}

.sm-course-card:hover{
  transform:translateY(-2px);
  box-shadow:0 18px 35px rgba(15,23,42,.09);
}

.sm-pill{
  display:inline-flex;
  align-items:center;
  gap:8px;
  padding:7px 14px;
  border-radius:999px;
  background:linear-gradient(135deg,#edf8f1,#fbfffc);
  color:var(--green);
  font-size:13px;
  font-weight:900;
  box-shadow:inset 0 0 0 1px rgba(31,111,74,.10);
}

.sm-course-title{
  font-size: 24px;
  line-height: 1.18;
  margin-top: 12px;
   color:#19222d;
  letter-spacing:-.02em;
  font-weight: 900;
}

.sm-course-desc{
  font-size: 14px;
  line-height: 1.65;
  margin-top: 8px;
  color: #6b7280;
}

/* =========================
   Section heading
========================= */
.sm-toc{
  margin-top:14px !important;
}

.sm-toc h2,
.sm-toc h3{
  font-size: 24px;
  line-height: 1.18;
  letter-spacing: -.015em;
  color: #18212b;
  font-weight: 900;
}

.sm-toc .text-muted{
  font-size: 15px;
  line-height: 1.5;
  color: #7b8190 !important;
}




.sm-chapter-card.is-current{
  border: 2px solid rgba(31,111,74,.28);
  box-shadow: 0 16px 34px rgba(31,111,74,.10);
}

.sm-chapter-card.is-viewed{
  position: relative;
}

.sm-chapter-status{
  display:inline-flex;
  align-items:center;
  gap:6px;
  padding:4px 10px;
  border-radius:999px;
  font-size:12px;
  font-weight:800;
  margin-top:8px;
}

.sm-chapter-status.sm-current{
  background:#eaf7ef;
  color:#1f6f4a;
}

.sm-chapter-status.sm-viewed{
  background:#eef2f7;
  color:#475467;
}



/* =========================
   Chapter list
========================= */
.sm-toc .sm-chapter-card{
  display:block;
  border-radius:26px;
  border:1px solid rgba(17,24,39,.05);
  box-shadow:
    0 14px 30px rgba(15,23,42,.05),
    inset 0 1px 0 rgba(255,255,255,.7);
  overflow:hidden;
  transition:.18s ease;
}

.sm-toc .sm-chapter-card:hover{
  transform:translateY(-2px);
  box-shadow:0 18px 34px rgba(15,23,42,.08);
}

.sm-toc .sm-chapter-card:nth-child(1){
  background:linear-gradient(135deg,#f7fff9,#f4fbf7);
}
.sm-toc .sm-chapter-card:nth-child(2){
  background:linear-gradient(135deg,#fffdf7,#fff8eb);
}
.sm-toc .sm-chapter-card:nth-child(3){
  background:linear-gradient(135deg,#f8fbff,#f2f7ff);
}
.sm-toc .sm-chapter-card:nth-child(4){
  background:linear-gradient(135deg,#fff8fb,#fff2f6);
}
.sm-toc .sm-chapter-card:nth-child(5){
  background:linear-gradient(135deg,#fbf9ff,#f5f1ff);
}

.sm-chapter-grid{
  display:grid;
  grid-template-columns:156px 1fr;
  gap:0;
}

.sm-chapter-left{
  padding:14px;
  background:rgba(255,255,255,.45);
  box-shadow:inset -1px 0 0 rgba(17,24,39,.05);
}

.sm-chapter-pill{
  display:inline-flex;
  align-items:center;
  gap:6px;
  padding:7px 11px;
  border-radius:999px;
  background:rgba(255,255,255,.72);
  color:var(--green);
  font-size:12px;
  font-weight:900;
  box-shadow:inset 0 0 0 1px rgba(31,111,74,.10);
}

.sm-chapter-pill .dot{
  opacity:.65;
}

.sm-chapter-img{
  width:100%;
  height:84px;
  object-fit:cover;
  border-radius:16px;
  display:block;
  margin-top:10px;
  background:#eef2f3;
  box-shadow:0 10px 20px rgba(15,23,42,.08);
}

.sm-chapter-right{
  padding:18px 22px;
  display:flex;
  flex-direction:column;
  justify-content:center;
}

.sm-chapter-title{
  font-size: 18px;
  line-height: 1.22;
  margin-bottom: 6px;
  font-weight: 800;
}

.sm-chapter-desc{
  font-size: 13px;
  line-height: 1.55;
  color: #6b7280;
}

.sm-chapter-right .small,
.sm-chapter-right .small.text-muted{
  font-size: 12px !important;
  line-height: 1.35;
}

.sm-chapter-card.is-soon{
  opacity:.94;
}

.sm-chapter-card.is-soon .sm-chapter-pill{
  background:#fff1e8;
  color:#9a6b3d;
}

/* =========================
   Reader
========================= */
.ch-wrap{
  max-width:1100px;
  margin:0 auto;
  padding:18px 14px 28px;
}

.ch-breadcrumb{
  display:flex;
  gap:8px;
  flex-wrap:wrap;
  align-items:center;
  margin:10px 0 14px;
  color:#64748b;
  font-size:13px;
}

.ch-breadcrumb a{
  font-weight:800;
}

.ch-breadcrumb .sep{
  opacity:.55;
}

.ch-card{
  background:
    linear-gradient(135deg, rgba(255,255,255,.98), rgba(251,249,244,.96));
  border-radius:30px;
  border:1px solid rgba(17,24,39,.05);
  box-shadow:
    0 20px 44px rgba(15,23,42,.07),
    inset 0 1px 0 rgba(255,255,255,.7);
  overflow:hidden;
}

.ch-head{
  display:grid;
  grid-template-columns:260px 1fr;
  gap:24px;
  align-items:center;
  padding:26px;
  background:
    linear-gradient(135deg, rgba(255,255,255,.95), rgba(245,250,247,.94));
  border-bottom:1px solid rgba(17,24,39,.05);
}

.ch-head-media{
  display:flex;
  flex-direction:column;
}

.ch-head-content{
  display:flex;
  flex-direction:column;
  justify-content:center;
}

.ch-pill{
  display:inline-flex;
  gap:8px;
  align-items:center;
  background:linear-gradient(135deg,#eef8f1,#fbfffc);
  color:var(--green);
  font-weight:900;
  font-size:13px;
  padding:8px 14px;
  border-radius:999px;
  box-shadow:inset 0 0 0 1px rgba(31,111,74,.10);
}

.ch-thumb{
  width:100%;
  height:170px;
  border-radius:20px;
  overflow:hidden;
  background:#eef2f3;
  border:1px solid rgba(17,24,39,.06);
  margin-top:12px;
  box-shadow:0 12px 28px rgba(15,23,42,.08);
}

.ch-thumb img{
  width:100%;
  height:100%;
  object-fit:cover;
  display:block;
}

.ch-title{
  margin:0 0 10px;
  font-size:30px;
  line-height:1.12;
  font-weight:900;
  letter-spacing:-.02em;
  color:#17212b;
}

.ch-sub{
  margin:0;
  color:#6b7280;
  line-height:1.7;
  font-size:15px;
}

.ch-meta-row{
  display:flex;
  gap:10px;
  flex-wrap:wrap;
  margin-top:16px;
}

.ch-meta-pill{
  display:inline-flex;
  align-items:center;
  gap:8px;
  padding:7px 12px;
  border-radius:999px;
  background:rgba(255,255,255,.78);
  border:1px solid rgba(17,24,39,.08);
  color:#4b5563;
  font-size:13px;
  box-shadow:0 6px 18px rgba(15,23,42,.04);
}

.ch-meta-pill strong{
  color:#1f2937;
  font-weight:800;
}

.ch-head-actions{
  display:flex;
  gap:10px;
  flex-wrap:wrap;
  margin-top:18px;
}

.ch-head-actions .btn{
  border-radius:14px;
  padding:10px 14px;
  font-weight:800;
  border:1px solid rgba(31,111,74,.14);
  background:linear-gradient(135deg,#f3fbf6,#fcfffd);
  color:#234b36;
  box-shadow:0 8px 18px rgba(31,111,74,.05);
}

.ch-head-actions .btn:hover{
  background:linear-gradient(135deg,#ecf8ef,#f7fcf9);
  border-color:rgba(31,111,74,.22);
  color:#1f6f4a;
}

.ch-body{
  padding:26px 26px 28px;
}

.ch-body .prose{
  max-width:860px;
  font-size:17px;
  line-height:1.95;
  color:#111827;
}

.ch-body .prose p{
  margin:0 0 14px;
}

.ch-body h2{
  font-size:24px;
  margin:28px 0 12px;
  line-height:1.2;
  color:#18212b;
}

.ch-body h3{
  font-size:20px;
  margin:22px 0 10px;
  line-height:1.25;
  color:#213043;
}

.ch-body ul,
.ch-body ol{
  margin:12px 0 14px;
  padding-left:22px;
}

.ch-body li{
  margin:7px 0;
}

.ch-body table{
  width:100%;
  border-collapse:collapse;
  margin:18px 0;
  overflow:hidden;
  border-radius:16px;
  background:#fff;
  box-shadow:0 10px 24px rgba(15,23,42,.05);
}

.ch-body table th,
.ch-body table td{
  border:1px solid rgba(17,24,39,.08);
  padding:10px 12px;
  vertical-align:top;
}

.ch-body table th{
  background:#eef8f1;
  color:#1f6f4a;
  font-weight:800;
}

.ch-body blockquote{
  margin:18px 0;
  padding:14px 16px;
  border-left:4px solid var(--green);
  background:#f8fcf9;
  border-radius:12px;
  color:#334155;
}

.ch-body img{
  max-width:100%;
  height:auto;
  border-radius:18px;
  display:block;
  margin:18px 0;
  box-shadow:0 12px 28px rgba(15,23,42,.08);
}

.ch-nav{
  display:flex;
  gap:12px;
  flex-wrap:wrap;
  justify-content:space-between;
  align-items:center;
  padding:18px 24px;
  border-top:1px solid rgba(17,24,39,.06);
  background:linear-gradient(180deg,#fff,#fbfaf7);
}

.ch-nav .btn{
  display:inline-block;
  padding:11px 16px;
  border-radius:14px;
  font-weight:900;
  border:1px solid rgba(17,24,39,.12);
  background:#f8fafc;
  color:#0f172a;
  box-shadow:0 8px 18px rgba(15,23,42,.04);
}

.ch-nav .btn.primary{
  background:linear-gradient(135deg,#1f6f4a,#2fa36a);
  border-color:transparent;
  color:#fff;
}

.ch-nav .btn.disabled{
  opacity:.45;
  pointer-events:none;
}

/* =========================
   Footer
========================= */
.course-footer{
  margin-top:28px;
  background:#fff;
  border-top:1px solid rgba(17,24,39,.06);
}

.course-footer-inner{
  max-width:1120px;
  margin:0 auto;
  padding:16px 14px;
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap:14px;
  flex-wrap:wrap;
}

.course-footer-left,
.course-footer-right{
  display:flex;
  align-items:center;
  gap:12px;
  flex-wrap:wrap;
}

.course-footer-brand{
  display:flex;
  align-items:center;
  gap:8px;
  color:var(--ink);
}

.course-footer-copy{
  color:var(--muted);
  font-size:13px;
}

.course-footer-link{
  color:var(--ink);
  font-weight:700;
  font-size:13px;
}

.course-footer-link:hover{
  color:var(--green);
}

.course-footer-tip{
  font-size:13px;
}

/* =========================
   Utility
========================= */
.pills{
  display:flex;
  flex-wrap:wrap;
  gap:10px;
}

.pill{
  display:inline-flex;
  align-items:center;
  gap:6px;
  padding:7px 12px;
  border-radius:999px;
  background:#eef8f1;
  color:var(--green);
  font-weight:700;
  font-size:13px;
}

/* =========================
   Responsive
========================= */
@media (max-width: 900px){
  .sm-book-hero{
    padding:22px;
  }

  .sm-hero-title{
    font-size:30px;
  }

  .ch-head{
    grid-template-columns:1fr;
  }
}

@media (max-width: 768px){

  .course-main{
    padding:12px 10px 24px;
  }

  .course-wrap{
    max-width:100%;
  }

  .course-topbar-inner{
    position:relative;
    display:flex;
    flex-wrap:wrap;
    align-items:flex-start;
    gap:8px;
    padding:10px 10px 8px;
  }

  .course-brand{
    flex:1 1 auto;
    min-width:0;
    gap:8px;
    padding-right:140px;
  }

  .course-brand-icn{
    width:36px;
    height:36px;
  }

  .course-brand-name{
    font-size:14px;
  }

  .course-brand-sub{
    font-size:11px;
  }

  .course-controls{
    position:absolute;
    top:10px;
    right:10px;
    width:auto;
    margin:0;
    justify-content:flex-end;
    z-index:2;
  }

  .course-controls .btn,
  .course-controls .btn-group,
  .course-controls a.btn{
    white-space:nowrap;
  }

  .course-nav{
    width:100%;
    gap:8px;
    justify-content:flex-start;
    margin-top:6px;
  }

  .course-navlink{
    padding:7px 11px;
    font-size:13px;
  }

  /* HERO mobile */
  .sm-book-hero{
    padding:18px 16px 18px;
    border-radius:22px;
  }

  .sm-book-hero::before,
  .sm-book-hero::after{
    opacity:.55;
  }

  .sm-hero-title{
  font-size: 18px;
  line-height: 1.2;
  margin: 10px 0 6px;
}
  

  .sm-hero-sub{
  font-size: 13px;
  line-height: 1.5;
}

  .sm-hero-actions{
    gap:10px;
    margin-top:14px !important;
  }

  .sm-hero-actions .btn{
    padding:10px 14px;
    font-size:14px;
    border-radius:14px;
  }

  .sm-hero-tip{
    font-size:13px !important;
    line-height:1.45;
    margin-top:10px !important;
  }

  .sm-hero-cover{
    min-height:auto;
    margin-top:16px;
    padding:8px;
    border-radius:20px;
    background:linear-gradient(180deg,#eef4f2,#f7f3ee);
  }

  .sm-hero-cover img{
  width:auto;
  max-width:82%;
  height:auto !important;
  max-height:165px;
  object-fit:contain !important;
  display:block;
  margin:0 auto;
  border-radius:14px;
  box-shadow:0 8px 18px rgba(15,23,42,.08);
}

  /* Featured card mobile */
  .sm-course-card{
    padding:18px 16px !important;
    border-radius:22px;
  }

  .sm-course-title{
    font-size:18px;
    line-height:1.18;
  }

  .sm-course-desc{
    font-size:14px;
    line-height:1.6;
  }

  .sm-course-card .btn{
    padding:8px 12px;
    font-size:13px;
    border-radius:12px;
  }

  /* TOC heading */
  .sm-toc h2,
.sm-toc h3{
  font-size: 18px;
  line-height: 1.2;
  margin-bottom: 4px !important;
}

  .sm-toc .text-muted{
    font-size:14px;
    line-height:1.45;
  }

  .sm-toc .course-navlink{
    padding:7px 11px;
    font-size:13px;
    border-radius:12px;
  }

  /* Chapter cards mobile */
  .sm-chapter-card{
    border-radius:18px;
  }
  
.sm-chapter-status{
    font-size:11px;
    padding:4px 8px;
  }

 .sm-chapter-grid{
  grid-template-columns:88px 1fr;
  gap:0;
}
  .sm-chapter-left{
    padding:10px;
  }

  .sm-chapter-pill{
    font-size:10px;
    padding:5px 8px;
    gap:4px;
  }

  .sm-chapter-img{
    height:62px;
    border-radius:12px;
    margin-top:8px;
  }

  .sm-chapter-right{
  padding:12px 12px 12px 4px;
}

  .sm-chapter-title{
  font-size: 14px;
  line-height: 1.25;
  margin-bottom: 3px;
  font-weight: 800;
}

  .sm-chapter-desc{
  font-size: 12px;
  line-height: 1.4;
}

.sm-chapter-right .small,
.sm-chapter-right .small.text-muted{
  font-size: 11px !important;
  line-height: 1.3;
}


  /* Reader mobile */
  .ch-wrap{
    padding:14px 10px 24px;
  }

  .ch-card{
    border-radius:22px;
  }

  .ch-head{
    grid-template-columns:1fr;
    gap:16px;
    padding:18px 16px;
  }

  .ch-thumb{
  height:auto;
  min-height:unset;
  padding:10px;
  border-radius:16px;
  display:flex;
  align-items:center;
  justify-content:center;
  background:linear-gradient(180deg,#eef4f2,#f7f3ee);
}

.ch-thumb img{
  width:auto;
  max-width:100%;
  height:auto !important;
  max-height:220px;
  object-fit:contain !important;
  object-position:center center;
  display:block;
  margin:0 auto;
  border-radius:14px;
}

  .ch-title{
    font-size:26px;
    line-height:1.12;
    margin:0 0 8px;
  }

  .ch-sub{
    font-size:14px;
    line-height:1.65;
  }

  .ch-meta-row{
    margin-top:12px;
    gap:8px;
  }

  .ch-meta-pill{
    font-size:12px;
    padding:6px 10px;
  }

  .ch-head-actions{
    display:flex;
    gap:8px;
    flex-wrap:wrap;
    margin-top:14px;
  }

  .ch-head-actions .btn{
    font-size:13px;
    padding:9px 12px;
    border-radius:12px;
  }

  .ch-body{
    padding:18px 16px 20px;
  }

  .ch-body .prose{
    font-size:15px;
    line-height:1.85;
  }

  .ch-body h2{
    font-size:20px;
    margin:22px 0 10px;
  }

  .ch-body h3{
    font-size:18px;
    margin:18px 0 9px;
  }

  .ch-nav{
    display:grid;
    grid-template-columns:1fr auto 1fr;
    align-items:center;
    gap:10px;
    padding:16px;
  }

  .ch-nav > div{
    min-width:0;
  }

  .ch-nav > div:nth-child(1){
    display:flex;
    justify-content:flex-start;
  }

  .ch-nav > div:nth-child(2){
    display:flex;
    justify-content:center;
  }

  .ch-nav > div:nth-child(3){
    display:flex;
    justify-content:flex-end;
  }

  .ch-nav .btn{
    padding:10px 12px;
    font-size:13px;
    border-radius:12px;
    white-space:nowrap;
  }

  .course-footer-inner{
    padding:14px 12px;
  }

  .course-footer-copy,
  .course-footer-link,
  .course-footer-tip{
    font-size:12px;
  }
}

@media (max-width: 420px){
  .sm-hero-title{
    font-size:17px;
    line-height:1.22;
  }

  .sm-hero-cover img{
    max-width:80%;
    max-height:150px;
  }

  .sm-chapter-grid{
    grid-template-columns:84px 1fr;
  }

  .sm-chapter-img{
    height:56px;
  }
  
  .ch-thumb img{
    max-height:180px;
  }
}