/* =========================================================
   PÁGINA DA AULA — BIBLIOTECA MAHAL
   ========================================================= */

:root {
  --lesson-bg: #0d0d0f;
  --lesson-surface: #151518;
  --lesson-surface-hover: #1d1d21;
  --lesson-border: rgba(255, 255, 255, 0.14);
  --lesson-border-strong: rgba(255, 255, 255, 0.24);

  --lesson-text: #f5f2f7;
  --lesson-muted: #aaa5b0;

  --lesson-orange: #ff6500;
  --lesson-orange-hover: #ff7a22;

  --lesson-purple: #d6a8ff;
  --lesson-purple-hover: #e4c5ff;

  --lesson-radius: 14px;
  --lesson-transition: 180ms ease;
}

/* =========================================================
   ESTRUTURA PRINCIPAL
   ========================================================= */

.lesson-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 320px;
  align-items: start;
  gap: 20px;
  width: 100%;
  max-width: 1680px;
  margin: 0 auto;
}

.lesson-main {
  min-width: 0;
}

.lesson-main > h1 {
  margin: 0;
  color: var(--lesson-text);
  font-size: clamp(2rem, 3vw, 3.1rem);
  font-weight: 800;
  line-height: 1.08;
  letter-spacing: -0.035em;
  overflow-wrap: anywhere;
}

.lesson-context {
  margin: 14px 0 18px;
  color: var(--lesson-muted);
  font-size: 0.95rem;
  line-height: 1.5;
}

/* =========================================================
   CONTEÚDO E VÍDEO
   ========================================================= */

.lesson-content {
  width: 100%;
  padding: 12px;
  background: var(--lesson-bg);
  border: 1px solid var(--lesson-border-strong);
  border-radius: var(--lesson-radius);
  box-sizing: border-box;
  overflow: hidden;
}

.video-embed {
  position: relative;
  width: 100%;
  aspect-ratio: 16 / 9;
  background: #050505;
  border-radius: 11px;
  overflow: hidden;
}

.video-embed iframe {
  position: absolute;
  inset: 0;
  display: block;
  width: 100%;
  height: 100%;
  border: 0;
}

.video-file {
  width: 100%;
}

.video-file video {
  display: block;
  width: 100% !important;
  max-width: none !important;
  border-radius: 11px !important;
  background: #050505;
}

/*
 * Garante responsividade quando embed_html contém
 * iframe ou vídeo sem a classe .video-embed.
 */
.lesson-content > iframe,
.lesson-content iframe:not(.video-embed iframe) {
  display: block;
  width: 100%;
  max-width: 100%;
  aspect-ratio: 16 / 9;
  height: auto;
  border: 0;
  border-radius: 11px;
}

.lesson-content img {
  max-width: 100%;
  height: auto;
}

/* =========================================================
   NAVEGAÇÃO
   ========================================================= */

.lesson-navigation {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
  margin-top: 14px;
}

.lesson-navigation a,
.lesson-complete-button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 42px;
  padding: 10px 16px;
  border-radius: 9px;
  box-sizing: border-box;
  font-family: inherit;
  font-size: 0.92rem;
  font-weight: 700;
  line-height: 1;
  text-decoration: none;
  cursor: pointer;
  transition:
    color var(--lesson-transition),
    background var(--lesson-transition),
    border-color var(--lesson-transition),
    transform var(--lesson-transition);
}

.lesson-navigation a {
  color: var(--lesson-purple);
  background: var(--lesson-surface);
  border: 1px solid var(--lesson-border);
}

.lesson-navigation a:hover {
  color: var(--lesson-purple-hover);
  background: var(--lesson-surface-hover);
  border-color: rgba(214, 168, 255, 0.55);
  transform: translateY(-1px);
}

.lesson-complete-button {
  margin-left: auto;
  color: #fff;
  background: var(--lesson-orange);
  border: 1px solid var(--lesson-orange);
  box-shadow: 0 10px 30px rgba(255, 101, 0, 0.16);
}

.lesson-complete-button:hover {
  background: var(--lesson-orange-hover);
  border-color: var(--lesson-orange-hover);
  transform: translateY(-1px);
}

.lesson-navigation a:focus-visible,
.lesson-complete-button:focus-visible,
.lesson-list-item:focus-visible {
  outline: 3px solid rgba(214, 168, 255, 0.42);
  outline-offset: 3px;
}

/* =========================================================
   DESCRIÇÃO
   ========================================================= */

.lesson-description {
  margin-top: 22px;
  padding: clamp(18px, 2.3vw, 28px);
  color: var(--lesson-text);
  background:
    linear-gradient(
      135deg,
      rgba(255, 101, 0, 0.055),
      transparent 38%
    ),
    var(--lesson-surface);
  border: 1px solid var(--lesson-border);
  border-radius: var(--lesson-radius);
}

.lesson-description h2 {
  position: relative;
  margin: 0 0 14px;
  padding-left: 15px;
  color: var(--lesson-text);
  font-size: clamp(1.2rem, 2vw, 1.55rem);
  font-weight: 800;
  line-height: 1.25;
}

.lesson-description h2::before {
  content: "";
  position: absolute;
  top: 0.12em;
  bottom: 0.12em;
  left: 0;
  width: 4px;
  background: var(--lesson-orange);
  border-radius: 999px;
}

.lesson-description p {
  margin: 0;
  color: #cbc7d0;
  font-size: 1rem;
  line-height: 1.75;
  overflow-wrap: anywhere;
}

/* =========================================================
   LISTA LATERAL
   ========================================================= */

.lesson-sidebar {
  position: sticky;
  top: 18px;
  width: 100%;
  min-width: 0;
  padding: 16px;
  color: var(--lesson-text);
  background: var(--lesson-bg);
  border: 1px solid var(--lesson-border-strong);
  border-radius: var(--lesson-radius);
  box-sizing: border-box;
}

.lesson-sidebar > strong {
  display: block;
  padding-bottom: 13px;
  color: var(--lesson-text);
  font-size: 1rem;
  font-weight: 800;
  border-bottom: 1px solid var(--lesson-border);
}

.lesson-list {
  display: flex;
  flex-direction: column;
  gap: 7px;
  max-height: calc(100vh - 160px);
  margin-top: 12px;
  padding-right: 4px;
  overflow-y: auto;
  overscroll-behavior: contain;
  scrollbar-color: var(--lesson-orange) transparent;
  scrollbar-width: thin;
}

.lesson-list::-webkit-scrollbar {
  width: 5px;
}

.lesson-list::-webkit-scrollbar-track {
  background: transparent;
}

.lesson-list::-webkit-scrollbar-thumb {
  background: var(--lesson-orange);
  border-radius: 999px;
}

.lesson-list-item {
  display: block;
  padding: 11px 12px;
  color: var(--lesson-purple);
  background: transparent;
  border: 1px solid transparent;
  border-radius: 9px;
  font-size: 0.92rem;
  font-weight: 600;
  line-height: 1.45;
  text-decoration: none;
  overflow-wrap: anywhere;
  transition:
    color var(--lesson-transition),
    background var(--lesson-transition),
    border-color var(--lesson-transition),
    transform var(--lesson-transition);
}

.lesson-list-item:hover {
  color: var(--lesson-purple-hover);
  background: var(--lesson-surface-hover);
  border-color: var(--lesson-border);
  transform: translateX(2px);
}

.lesson-list-item.is-active {
  color: #17131a;
  background: linear-gradient(135deg, #f4eaff, #d6a8ff);
  border-color: transparent;
  font-weight: 800;
}

/* =========================================================
   TABLETS E NOTEBOOKS MENORES
   ========================================================= */

@media (max-width: 1100px) {
  .lesson-layout {
    grid-template-columns: minmax(0, 1fr);
  }

  .lesson-sidebar {
    position: static;
  }

  .lesson-list {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    max-height: none;
    overflow: visible;
  }

  .lesson-list-item:hover {
    transform: translateY(-1px);
  }
}

/* =========================================================
   MOBILE
   ========================================================= */

@media (max-width: 640px) {
  .lesson-layout {
    display: flex;
    flex-direction: column;
    gap: 18px;
    width: 100%;
  }

  .lesson-main,
  .lesson-sidebar {
    width: 100%;
  }

  .lesson-main > h1 {
    font-size: clamp(1.75rem, 9vw, 2.35rem);
    line-height: 1.12;
  }

  .lesson-context {
    margin: 10px 0 14px;
    font-size: 0.88rem;
  }

  .lesson-content {
    padding: 5px;
    border-radius: 11px;
  }

  .video-embed,
  .video-file video,
  .lesson-content > iframe {
    border-radius: 8px !important;
  }

  .lesson-navigation {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 8px;
    margin-top: 10px;
  }

  .lesson-navigation a,
  .lesson-complete-button {
    width: 100%;
    min-height: 44px;
    padding: 10px 12px;
    font-size: 0.86rem;
    text-align: center;
  }

  .lesson-complete-button {
    grid-column: 1 / -1;
    margin-left: 0;
  }

  /*
   * Se existir apenas um link de navegação, ele continua
   * ocupando metade da linha. O botão ocupa toda a largura.
   */
  .lesson-description {
    margin-top: 18px;
    padding: 17px;
    border-radius: 11px;
  }

  .lesson-description h2 {
    margin-bottom: 11px;
    font-size: 1.2rem;
  }

  .lesson-description p {
    font-size: 0.94rem;
    line-height: 1.65;
  }

  .lesson-sidebar {
    padding: 14px;
    border-radius: 11px;
  }

  .lesson-list {
    display: flex;
    max-height: 360px;
    overflow-y: auto;
  }

  .lesson-list-item {
    padding: 12px;
  }
}

/* =========================================================
   CELULARES PEQUENOS
   ========================================================= */

@media (max-width: 380px) {
  .lesson-navigation {
    grid-template-columns: 1fr;
  }

  .lesson-complete-button {
    grid-column: auto;
  }
}

/* =========================================================
   ACESSIBILIDADE
   ========================================================= */

@media (prefers-reduced-motion: reduce) {
  .lesson-navigation a,
  .lesson-complete-button,
  .lesson-list-item {
    transition: none;
  }
}