:root {
  --primary: #6366f1;
  --primary-hover: #4f46e5;
  --bg-light: #f8fafc;
  --bg-dark: #0f172a;
  --card-bg-light: rgba(255, 255, 255, 0.8);
  --card-bg-dark: rgba(30, 41, 59, 0.7);
  --border-light: rgba(226, 232, 240, 0.8);
  --border-dark: rgba(51, 65, 85, 0.5);
  --text-light: #1e293b;
  --text-dark: #f1f5f9;
  --text-muted-light: #64748b;
  --text-muted-dark: #94a3b8;
  --table-header-bg: rgba(99, 102, 241, 0.1);
  --category-bg: rgba(99, 102, 241, 0.2);
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  background-color: var(--bg-light);
  font-family: "Inter", system-ui, sans-serif;
  color: var(--text-light);
  line-height: 1.5;
  padding: 1rem 5rem;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  transition: background-color 0.3s ease;
}

.dark body {
  background-color: var(--bg-dark);
  color: var(--text-dark);
}

.container {
  max-width: 1000px;
  margin: 0 auto;
  width: 100%;
}

header {
  text-align: center;
  margin-bottom: 4rem;
}

.logo-container {
  display: flex;
  justify-content: center;
  margin-bottom: 2rem;
}

.logo {
  height: 120px;
  width: auto;
  border-radius: 12px;
  object-fit: contain;
}

h1 {
  font-family: "Outfit", sans-serif;
  font-size: 3rem;
  font-weight: 800;
  background: linear-gradient(135deg, #6366f1 0%, #a855f7 100%);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  letter-spacing: -0.02em;
  margin-bottom: 0.5rem;
}

.subtitle {
  font-size: 1.25rem;
  color: var(--text-muted-dark);
  font-weight: 500;
}

/* Navigation Grid (Index) */
.grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 2rem;
}

.nav-card {
  text-decoration: none;
  color: inherit;
  background: var(--card-bg-light);
  backdrop-filter: blur(12px);
  border: 1px solid var(--border-light);
  border-radius: 1.5rem;
  padding: 2.5rem 2rem;
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  gap: 1.5rem;
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  cursor: pointer;
}

.dark .nav-card {
  background: var(--card-bg-dark);
  border-color: var(--border-dark);
}

.nav-card:hover {
  transform: translateY(-8px);
  border-color: var(--primary);
  box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.2);
  background: rgba(99, 102, 241, 0.05);
}

.icon-circle {
  width: 80px;
  height: 80px;
  border-radius: 50%;
  background: rgba(99, 102, 241, 0.1);
  color: var(--primary);
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all 0.3s ease;
}

.nav-card:hover .icon-circle {
  background: var(--primary);
  color: white;
  transform: scale(1.1);
}

.card-title {
  font-family: "Outfit", sans-serif;
  font-size: 1.5rem;
  font-weight: 700;
}

.card-desc {
  font-size: 0.95rem;
  color: var(--text-muted-dark);
}

/* Back Button / Top Nav */
.top-nav {
  display: grid;
  grid-template-columns: 48px 1fr 48px;
  align-items: center;
  width: 100%;
  margin-bottom: 1rem;
}

.back-button {
  width: 48px;
  height: 48px;
  background: var(--card-bg-dark);
  border: 1px solid var(--border-dark);
  border-radius: 50%;
  color: var(--text-dark);
  display: flex;
  align-items: center;
  justify-content: center;
  text-decoration: none;
  transition: all 0.3s ease;
  backdrop-filter: blur(12px);
}

.back-button:hover {
  background: var(--primary);
  color: white;
  transform: scale(1.1);
  border-color: var(--primary);
}

/* Footer & Status Bar */
footer {
  margin-top: 4rem;
  text-align: center;
  padding-top: 2rem;
  border-top: 1px solid var(--border-dark);
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 0.5rem;
  color: var(--text-muted-dark);
  font-weight: 600;
}

/* Specific Page: Acesso (QR Code Card) */
.card {
  background: var(--card-bg-light);
  backdrop-filter: blur(12px);
  border: 1px solid var(--border-light);
  border-radius: 1.5rem;
  padding: 3rem 2rem;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 2rem;
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
}

.dark .card {
  background: var(--card-bg-dark);
  border-color: var(--border-dark);
  box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.5);
}

.qr-wrapper {
  background: white;
  padding: 1.5rem;
  border-radius: 1.25rem;
  box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
  display: flex;
  align-items: center;
  justify-content: center;
  transition: transform 0.3s ease;
}

.qr-wrapper:hover {
  transform: scale(1.02);
}

.qrcode {
  width: 240px;
  height: 240px;
  display: block;
}

.info-section {
  text-align: center;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.url {
  font-family: "Outfit", sans-serif;
  font-size: 1.75rem;
  color: var(--primary);
  text-decoration: none;
  font-weight: 700;
  transition: color 0.2s;
}

.url:hover {
  color: var(--primary-hover);
  text-decoration: underline;
}

.instruction {
  font-size: 1.1rem;
  color: var(--text-muted-light);
  font-weight: 500;
}

.dark .instruction {
  color: var(--text-muted-dark);
}

/* Specific Page: Avaliações (Grading) */
.teacher-info {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-weight: 600;
  font-size: 1.1rem;
  color: var(--text-muted-light);
}

.dark .teacher-info {
  color: var(--text-muted-dark);
}

.eval-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 2rem;
}

.eval-card {
  background: var(--card-bg-light);
  backdrop-filter: blur(12px);
  border: 1px solid var(--border-light);
  border-radius: 1.25rem;
  padding: 1.75rem;
  display: flex;
  flex-direction: column;
  gap: 1rem;
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  position: relative;
  overflow: hidden;
}

.dark .eval-card {
  background: var(--card-bg-dark);
  border-color: var(--border-dark);
  box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
}

.eval-card:hover {
  transform: translateY(-5px);
  box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
  border-color: var(--primary);
}

.icon-wrapper {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border-radius: 10px;
  background: rgba(99, 102, 241, 0.1);
  color: var(--primary);
}

.value-badge {
  background: var(--primary);
  color: white;
  padding: 0.25rem 0.75rem;
  border-radius: 2rem;
  font-weight: 700;
  font-size: 0.875rem;
  box-shadow: 0 4px 6px -1px rgba(99, 102, 241, 0.3);
}

/* Specific Page: Provão Paulista (Tables) */
.table-wrapper {
  background: var(--card-bg-light);
  backdrop-filter: blur(12px);
  border: 1px solid var(--border-light);
  border-radius: 1.25rem;
  overflow: hidden;
  box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
}

.dark .table-wrapper {
  background: var(--card-bg-dark);
  border-color: var(--border-dark);
}

table {
  width: 100%;
  border-collapse: collapse;
  text-align: left;
}

th, td {
  padding: 1rem 1.5rem;
  border-bottom: 1px solid var(--border-light);
}

.dark th, .dark td {
  border-bottom-color: var(--border-dark);
}

thead th {
  background: linear-gradient(135deg, rgba(99, 102, 241, 0.25) 0%, rgba(168, 85, 247, 0.25) 100%);
  font-family: "Outfit", sans-serif;
  font-weight: 800;
  color: var(--text-dark);
  text-transform: uppercase;
  font-size: 1.1rem;
  letter-spacing: 0.05em;
  border-bottom: 3px solid var(--primary);
}

.dark thead th {
  color: #fff;
}

.category-row {
  background: var(--category-bg);
}

.category-row td {
  font-family: "Outfit", sans-serif;
  font-weight: 700;
  color: var(--text-dark);
  font-size: 1.1rem;
}

.check-column {
  text-align: center;
  width: 80px;
  font-weight: 800;
  color: var(--primary);
  border-left: 1px solid var(--border-light);
}

.dark .check-column {
  border-left-color: var(--border-dark);
}

.x-mark {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 24px;
  height: 24px;
  background: var(--primary);
  color: white;
  border-radius: 6px;
  font-size: 0.75rem;
}

/* Mobile Responsiveness */
@media (max-width: 900px) {
  .grid {
    grid-template-columns: 1fr;
    max-width: 500px;
    margin: 0 auto;
  }
  body {
    padding: 2rem;
  }
}

@media (max-width: 640px) {
  body {
    padding: 1rem;
  }
  h1 {
    font-size: 2rem;
  }
  .eval-grid {
    grid-template-columns: 1fr;
  }
  .download-status {
    width: 100%;
    margin-left: 0;
    margin-top: 0.5rem;
    padding-left: 2rem; /* Alinhamento com o texto do nome do arquivo */
  }
  .qrcode {
    width: 200px;
    height: 200px;
  }
  .url {
    font-size: 1.5rem;
  }
}

/* List-based Layout (Shared by Aulas and Listas) */
.series-list {
  display: flex;
  flex-direction: column;
  gap: 2rem;
  margin-top: 2rem;
  width: 100%;
}

.series-section {
  background: var(--card-bg-light);
  backdrop-filter: blur(12px);
  border: 1px solid var(--border-light);
  border-radius: 1.5rem;
  padding: 0 2rem;
  transition: all 0.4s cubic-bezier(0.16, 1, 0.3, 1);
  overflow: hidden;
}

.dark .series-section {
  background: var(--card-bg-dark);
  border-color: var(--border-dark);
}

/* Estado ativo neutro */

.series-header {
  display: flex;
  align-items: center;
  gap: 1.25rem;
  padding: 1.5rem 0;
  cursor: pointer;
  user-select: none;
  position: relative;
}

.series-header::after {
  content: 'expand_more';
  font-family: 'Material Symbols Outlined';
  position: absolute;
  right: 0;
  font-size: 24px;
  color: var(--text-muted-dark);
  transition: transform 0.4s cubic-bezier(0.16, 1, 0.3, 1);
}

.series-section.active .series-header::after {
  transform: rotate(180deg);
  color: var(--primary);
}

.series-title {
  font-family: "Outfit", sans-serif;
  font-size: 1.5rem;
  font-weight: 700;
}

.file-container {
  display: grid;
  grid-template-rows: 0fr;
  transition: grid-template-rows 0.4s cubic-bezier(0.16, 1, 0.3, 1), 
              opacity 0.4s ease, 
              padding 0.4s ease;
  opacity: 0;
}

.series-section.active .file-container {
  grid-template-rows: 1fr;
  opacity: 1;
  padding-bottom: 2rem;
  padding-top: 1rem;
}

.file-inner {
  overflow: hidden;
}

.file-list {
  display: grid;
  grid-template-columns: 1fr;
  gap: 0.75rem;
  list-style: none;
  padding: 8px 2px; /* Espaço para não cortar o hover (transform: translateY) */
}

.file-item {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.85rem 1.25rem;
  background: rgba(99, 102, 241, 0.05);
  border-radius: 12px;
  text-decoration: none;
  color: inherit;
  font-size: 0.95rem;
  font-weight: 500;
  transition: all 0.2s ease;
  border: 1px solid transparent;
  flex-wrap: wrap;
}

.download-status {
  margin-left: auto;
  align-items: center;
  gap: 8px;
  font-size: 0.8rem;
  color: var(--primary);
  font-weight: 600;
}

.file-item:hover {
  background: rgba(99, 102, 241, 0.15);
  transform: translateY(-2px);
  border-color: var(--primary);
  color: var(--primary);
}

.file-icon {
  font-size: 20px !important;
}

.loading-spinner {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 1rem;
  padding: 2rem;
  color: var(--text-muted-dark);
}

.spinner {
  width: 40px;
  height: 40px;
  border: 4px solid rgba(99, 102, 241, 0.1);
  border-top: 4px solid var(--primary);
  border-radius: 50%;
  animation: spin 1s linear infinite;
}

@keyframes spin {
  0% { transform: rotate(0deg); }
  100% { transform: rotate(360deg); }
}

.spinner-mini {
  display: inline-block;
  width: 14px;
  height: 14px;
  border: 2px solid rgba(99, 102, 241, 0.2);
  border-top: 2px solid var(--primary);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}

.error-msg {
  color: #ef4444;
  text-align: center;
  padding: 1rem;
  font-size: 0.9rem;
}

/* Full-Page Preloader */
.preloader-overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: var(--bg-dark);
  z-index: 9999;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: opacity 0.6s cubic-bezier(0.16, 1, 0.3, 1), 
              visibility 0.6s cubic-bezier(0.16, 1, 0.3, 1);
}

.preloader-overlay.fade-out {
  opacity: 0;
  visibility: hidden;
}

.preloader-content {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 1.5rem;
  color: var(--text-dark);
  text-align: center;
}

.preloader-content p {
  font-family: "Outfit", sans-serif;
  font-weight: 600;
  font-size: 1.1rem;
  letter-spacing: 0.05em;
  color: var(--text-muted-dark);
}

.spinner-large {
  width: 60px;
  height: 60px;
  border: 4px solid rgba(99, 102, 241, 0.1);
  border-top: 4px solid var(--primary);
  border-radius: 50%;
  animation: spin 1s cubic-bezier(0.4, 0, 0.2, 1) infinite;
}

.dark .preloader-overlay {
  background: #0f172a;
}