:root{
  --radius: 18px;
  --radius-sm: 14px;
}

/* DARK */
:root,
:root[data-theme="dark"]{
  --page-bg: radial-gradient(1200px 800px at 20% 10%, rgba(64,90,255,0.18), transparent 60%),
             radial-gradient(900px 700px at 80% 30%, rgba(255,212,71,0.12), transparent 60%),
             #070b16;

  --panel: rgba(255,255,255,0.06);
  --panel-2: rgba(255,255,255,0.04);
  --border: rgba(255,255,255,0.10);
  --shadow: 0 18px 60px rgba(0,0,0,0.45);

  --text: rgba(255,255,255,0.92);
  --muted: rgba(255,255,255,0.62);

  --blue: #3b66ff;
  --blue-weak: rgba(59,102,255,0.18);

  --gold: #ffd447;
  --gold-weak: rgba(255,212,71,0.16);

  --input-bg: rgba(0,0,0,0.25);
  --input-border: rgba(255,255,255,0.12);
}

/* LIGHT */
:root[data-theme="light"]{
  --page-bg: #f5f7fb;
  --panel: #ffffff;
  --panel-2: #ffffff;
  --border: rgba(15,23,42,0.10);
  --shadow: 0 14px 44px rgba(15,23,42,0.10);

  --text: #0f172a;
  --muted: #64748b;

  --blue: #3b66ff;
  --blue-weak: rgba(59,102,255,0.10);

  --gold: #ffd447;
  --gold-weak: rgba(255,212,71,0.12);

  --input-bg: #ffffff;
  --input-border: rgba(15,23,42,0.12);
}

body{
  background: var(--page-bg);
}

/* ✅ FIX: remove 1260px cap + make layout scale correctly on 4K */
.coursepage{
  max-width: none;             /* was 1260px */
  width: 100%;
  margin: 0 auto;

  padding: 20px 24px 28px;     /* slightly wider gutters on large screens */
  display: grid;
  grid-template-columns: minmax(320px, 380px) minmax(600px, 1fr); /* was 340px 1fr */
  gap: 16px;

  min-height: calc(100vh - 140px);
  background: var(--page-bg);
}

/* Left outline panel */
.course-outline{
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  overflow: hidden;
  display:flex;
  flex-direction:column;
  min-height: 0;
  backdrop-filter: blur(10px);
}

.course-outline__top{
  padding: 14px 14px 10px;
  border-bottom: 1px solid var(--border);
  background: linear-gradient(180deg, rgba(255,255,255,0.04), transparent);
}

.course-outline__title{
  font-weight: 900;
  font-size: 13px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--muted);
  margin-bottom: 10px;
}

.course-filters{
  display:grid;
  gap: 10px;
}
.course-field{ display:grid; gap: 6px; }
.course-field__label{
  font-size: 12px;
  color: var(--muted);
}

.course-select{
  width:100%;
  padding: 11px 12px;
  border-radius: 14px;
  border: 1px solid var(--input-border);
  background: var(--input-bg);
  color: var(--text);
  outline: none;
}

.course-select:focus{
  border-color: rgba(59,102,255,0.45);
  box-shadow: 0 0 0 3px rgba(59,102,255,0.18);
}

.course-outline__list{
  padding: 10px;
  overflow:auto;
  min-height: 0;
}

/* Items */
.course-section{
  margin-bottom: 10px;
}
.course-section__head{
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap: 10px;
  padding: 10px 10px;
  border-radius: 14px;
  background: var(--panel-2);
  cursor:pointer;
  user-select:none;
  border: 1px solid rgba(255,255,255,0.06);
}
:root[data-theme="light"] .course-section__head{
  border: 1px solid rgba(15,23,42,0.06);
}
.course-section__title{
  font-weight: 900;
  font-size: 14px;
  color: var(--text);
}
.course-section__meta{
  font-size: 12px;
  color: var(--muted);
}
.course-section__items{
  margin-top: 8px;
  display:grid;
  gap: 8px;
}

.course-item{
  width:100%;
  text-align:left;
  border: 1px solid var(--border);
  border-radius: 14px;
  background: rgba(255,255,255,0.04);
  padding: 10px 10px;
  display:flex;
  gap: 10px;
  align-items:flex-start;
  cursor:pointer;
  backdrop-filter: blur(10px);
}
:root[data-theme="light"] .course-item{
  background: #fff;
}

.course-item:hover{
  background: rgba(255,255,255,0.06);
}
:root[data-theme="light"] .course-item:hover{
  background: rgba(15,23,42,0.02);
}

.course-item.is-active{
  border-color: rgba(59, 102, 255, 0.55);
  box-shadow: 0 0 0 3px rgba(59,102,255,0.18);
  background: var(--blue-weak);
}

.course-item__icon{
  width: 30px;
  height: 30px;
  border-radius: 12px;
  display:grid;
  place-items:center;
  flex: 0 0 auto;
  background: rgba(255,255,255,0.06);
  border: 1px solid rgba(255,255,255,0.08);
  color: var(--text);
  font-size: 14px;
}
:root[data-theme="light"] .course-item__icon{
  background: rgba(15,23,42,0.04);
  border: 1px solid rgba(15,23,42,0.08);
}

.course-item__body{ flex: 1 1 auto; min-width: 0; }
.course-item__title{
  font-weight: 900;
  font-size: 14px;
  line-height: 1.2;
  margin: 0 0 4px;
  color: var(--text);
}
.course-item__sub{
  font-size: 12px;
  color: var(--muted);
}

.course-badge{
  font-size: 11px;
  padding: 5px 9px;
  border-radius: 999px;
  border: 1px solid var(--border);
  color: var(--muted);
  background: rgba(255,255,255,0.04);
}
.course-badge--video{
  border-color: rgba(59,102,255,0.35);
  color: var(--blue);
  background: rgba(59,102,255,0.10);
}
.course-badge--quiz{
  border-color: rgba(255,212,71,0.35);
  color: rgba(255,212,71,0.95);
  background: var(--gold-weak);
}

/* Right surface */
.course-surface{
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  overflow:hidden;
  display:flex;
  flex-direction:column;
  min-height: 0;
  backdrop-filter: blur(10px);

  /* ✅ FIX: prevent collapse on ultra-wide/resolution edge cases */
  min-width: 600px;
}

.course-surface__header{
  padding: 16px 16px 12px;
  border-bottom: 1px solid var(--border);
  background: linear-gradient(180deg, rgba(255,255,255,0.05), transparent);
}

.course-crumbs{
  font-size: 13px;
  color: var(--muted);
  display:flex;
  gap: 8px;
  align-items:center;
}
.course-crumbs__sep{ opacity: 0.6; }

.course-headline{
  margin-top: 10px;
  display:grid;
  gap: 10px;
}

.course-headline__row{
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap: 12px;
}

.course-title{
  margin: 0;
  font-weight: 950;
  font-size: 26px;
  color: var(--text);
}

.course-outline-btn{
  border: 1px solid rgba(255,255,255,0.18);
  background: rgba(255,255,255,0.06);
  color: var(--text);
  border-radius: 999px;
  padding: 10px 12px;
  font-weight: 900;
  cursor:pointer;
}
:root[data-theme="light"] .course-outline-btn{
  border-color: rgba(15,23,42,0.12);
  background: rgba(15,23,42,0.03);
}
.course-outline-btn:hover{
  background: rgba(255,255,255,0.10);
}

.course-progressbar{
  width:100%;
  height: 10px;
  border-radius: 999px;
  background: rgba(255,255,255,0.10);
  overflow:hidden;
}
:root[data-theme="light"] .course-progressbar{
  background: rgba(15,23,42,0.08);
}

.course-progressbar__fill{
  height: 100%;
  background: var(--blue);
  border-radius: 999px;
}

.course-upnext{
  margin: 14px 16px 0;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 14px;
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap: 14px;
  background: linear-gradient(180deg, rgba(59,102,255,0.18), rgba(255,255,255,0.02));
}

.course-upnext__title{
  font-weight: 950;
  margin-bottom: 4px;
  color: var(--text);
}
.course-upnext__desc{
  color: var(--muted);
  font-size: 13px;
}

.course-btn{
  border: 1px solid transparent;
  border-radius: 999px;
  padding: 10px 14px;
  font-weight: 900;
  cursor:pointer;
}
.course-btn--primary{
  background: var(--blue);
  color:#fff;
}
.course-btn--primary:hover{ filter: brightness(0.98); }

.course-viewer{
  padding: 16px;
  overflow:auto;
  min-height: 0;
}

.course-media{
  border-radius: var(--radius);
  overflow:hidden;
  border: 1px solid var(--border);
  background: #000;
}

.course-frame{
  width:100%;
  height: min(72vh, 680px);
  border: 0;
  display:block;
  background:#000;
}

/* ===============================
   FIX: Quizzes render inside an iframe.
   The default .course-frame background is black (great for videos),
   but it can make HTML quizzes look invisible.
   Force ONLY the quiz iframe to use a white canvas.
   =============================== */
iframe#quizFrame.course-frame{
  background: #ffffff !important;
  color-scheme: light !important;
}

.course-media__actions{
  margin-top: 10px;
  display:flex;
  justify-content:flex-end;
}

.course-link{
  color: var(--gold);
  text-decoration:none;
  font-weight: 800;
}
.course-link:hover{ text-decoration: underline; }

.course-empty{
  display:grid;
  place-items:center;
  padding: 40px 16px;
}
.course-empty__card{
  max-width: 560px;
  width: 100%;
  border: 1px dashed rgba(255,255,255,0.22);
  border-radius: var(--radius);
  background: rgba(255,255,255,0.04);
  padding: 18px;
}
:root[data-theme="light"] .course-empty__card{
  border-color: rgba(15,23,42,0.18);
  background: #fff;
}

.course-empty__title{
  font-weight: 950;
  font-size: 18px;
  margin-bottom: 6px;
  color: var(--text);
}
.course-empty__desc{ color: var(--muted); }

/* Skeleton */
.course-skeleton{ display:grid; gap: 10px; padding: 10px; }
.course-skeleton__line{
  height: 12px;
  border-radius: 999px;
  background: rgba(255,255,255,0.10);
}
:root[data-theme="light"] .course-skeleton__line{
  background: rgba(15,23,42,0.10);
}

/* Mobile: outline drawer */
.course-backdrop{
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.55);
  z-index: 30;
}

/* Footer — MATCH your videos page footer area */
.mqa-footer{
  padding: 28px 16px 38px;
  text-align: center;
  color: rgba(255,255,255,0.70);
  background: transparent; /* let the page gradient show through */
}
:root[data-theme="light"] .mqa-footer{
  color: rgba(15,23,42,0.65);
}

.mqa-footer__inner{
  max-width: 1100px;
  margin: 0 auto;
}

.mqa-footer__line1{
  font-size: 13px;
  letter-spacing: 0.2px;
  margin-bottom: 6px;
}

.mqa-footer__line2{
  font-size: 13px;
  opacity: 0.85;
}

/* Desktop: hide Outline button (mobile only) */
@media (min-width: 981px){
  .course-outline-btn{ display:none; }
}

/* Mobile layout */
@media (max-width: 980px){
  .coursepage{
    grid-template-columns: 1fr;
    padding: 20px 16px 28px; /* keep tighter gutters on mobile */
  }

  .course-outline{
    position: fixed;
    top: 72px; /* below your injected header */
    left: 0;
    bottom: 0;
    width: min(420px, 92vw);
    transform: translateX(-110%);
    transition: transform 160ms ease;
    z-index: 40;
    border-radius: 0 18px 18px 0;
  }
  .course-outline.is-open{ transform: translateX(0); }

  .course-title{ font-size: 22px; }
  .course-frame{ height: min(70vh, 620px); }

  /* On mobile we must allow the right panel to shrink normally */
  .course-surface{ min-width: 0; }
}

/* ---- End-of-video "Next lesson" overlay (Khan-like) ---- */

.course-media {
  position: relative; /* enables overlay positioning */
}

.course-video-overlay {
  position: absolute;
  inset: 0;
  display: grid;
  place-items: center;
  padding: 18px;
  background: radial-gradient(900px 500px at 50% 60%, rgba(0,0,0,0.55), rgba(0,0,0,0.78));
  z-index: 5;
}

.course-video-overlay__card {
  width: min(540px, 92%);
  border: 1px solid rgba(255,255,255,0.16);
  border-radius: 18px;
  background: rgba(10, 14, 30, 0.62);
  backdrop-filter: blur(10px);
  padding: 16px 16px 14px;
  box-shadow: 0 18px 60px rgba(0,0,0,0.55);
}

:root[data-theme="light"] .course-video-overlay__card{
  background: rgba(255,255,255,0.85);
  border-color: rgba(15,23,42,0.14);
}

.course-video-overlay__label{
  font-size: 12px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  opacity: 0.85;
  margin-bottom: 8px;
}

.course-video-overlay__title{
  font-weight: 950;
  font-size: 18px;
  line-height: 1.2;
  margin-bottom: 12px;
}

.course-video-overlay__actions{
  display: flex;
  gap: 10px;
  justify-content: flex-end;
  flex-wrap: wrap;
}

.course-video-overlay__btn{
  border: 1px solid rgba(255,255,255,0.18);
  background: rgba(255,255,255,0.06);
  color: inherit;
  border-radius: 999px;
  padding: 10px 14px;
  font-weight: 900;
  cursor: pointer;
}

:root[data-theme="light"] .course-video-overlay__btn{
  border-color: rgba(15,23,42,0.14);
  background: rgba(15,23,42,0.04);
}

.course-video-overlay__btn--primary{
  border-color: rgba(59,102,255,0.45);
  background: rgba(59,102,255,0.22);
}

.course-video-overlay__btn:disabled{
  cursor: default;
}