/* ============================================================
   Uso Académico de la IA — Taller Práctico
   Facultad de Economía y Empresa — Universidad de Murcia
   Paleta de colores corporativa UMU
   ============================================================ */

/* --- Variables CSS --- */
:root {
  --umured: #C1272D;
  --umured-light: #d94a4f;
  --umured-bg: #fef2f2;
  --umuteal: #1B4F5C;
  --umutealdark: #0F2E36;
  --umuteallight: #2A7A8C;
  --umuteallight-bg: #e8f4f8;
  --umugray: #F2F2F2;
  --umugraymed: #E0E0E0;
  --umuwhite: #FFFFFF;
  --umutextdark: #1A1A2E;
  --umutextmed: #4A4A6A;
  --shadow-sm: 0 1px 3px rgba(0,0,0,0.08);
  --shadow-md: 0 4px 12px rgba(0,0,0,0.1);
  --shadow-lg: 0 8px 30px rgba(0,0,0,0.12);
  --radius: 10px;
  --radius-lg: 16px;
}

/* --- Reset & Base --- */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  font-family: 'Segoe UI', system-ui, -apple-system, sans-serif;
  color: var(--umutextdark);
  background: var(--umuwhite);
  line-height: 1.7;
}

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

a {
  color: var(--umuteallight);
  text-decoration: none;
  transition: color 0.2s;
}

a:hover {
  color: var(--umured);
}

/* --- Header / Navbar --- */
.navbar {
  background: var(--umutealdark);
  padding: 0.6rem 2rem;
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: var(--shadow-md);
}

.navbar-inner {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
}

.navbar-logo img {
  height: 42px;
}

.navbar-title {
  color: var(--umuwhite);
  font-size: 0.95rem;
  font-weight: 600;
  white-space: nowrap;
}

.navbar-links {
  display: flex;
  gap: 0.3rem;
  flex-wrap: wrap;
  justify-content: flex-end;
}

.navbar-links a {
  color: var(--umugraymed);
  font-size: 0.78rem;
  padding: 0.35rem 0.65rem;
  border-radius: 6px;
  transition: all 0.2s;
  white-space: nowrap;
}

.navbar-links a:hover,
.navbar-links a.active {
  background: rgba(255,255,255,0.12);
  color: var(--umuwhite);
}

/* --- Hero Section (index) --- */
.hero {
  background: linear-gradient(135deg, var(--umutealdark) 0%, var(--umuteal) 100%);
  color: var(--umuwhite);
  padding: 4rem 2rem 3.5rem;
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  top: -80px;
  right: -80px;
  width: 350px;
  height: 350px;
  background: var(--umuteallight);
  opacity: 0.12;
  border-radius: 50%;
}

.hero::after {
  content: '';
  position: absolute;
  bottom: -60px;
  left: -60px;
  width: 250px;
  height: 250px;
  background: var(--umured);
  opacity: 0.08;
  border-radius: 50%;
}

.hero-inner {
  max-width: 900px;
  margin: 0 auto;
  position: relative;
  z-index: 1;
  text-align: center;
}

.hero h1 {
  font-size: 2.6rem;
  font-weight: 700;
  margin-bottom: 0.5rem;
  line-height: 1.2;
}

.hero .subtitle {
  font-size: 1.15rem;
  color: var(--umugraymed);
  margin-bottom: 0.3rem;
}

.hero .meta {
  font-size: 0.95rem;
  color: rgba(255,255,255,0.6);
  margin-bottom: 1.5rem;
}

.hero .meta strong {
  color: var(--umuwhite);
}

.hero-divider {
  width: 80px;
  height: 3px;
  background: var(--umured);
  margin: 1.2rem auto;
}

.hero-actions {
  margin-top: 1.5rem;
}

.btn-hero {
  display: inline-block;
  background: var(--umured);
  color: var(--umuwhite) !important;
  padding: 0.75rem 1.8rem;
  border-radius: var(--radius);
  font-weight: 600;
  font-size: 1.05rem;
  text-decoration: none;
  transition: background 0.2s, transform 0.2s;
  box-shadow: 0 2px 8px rgba(0,0,0,0.25);
}

.btn-hero:hover {
  background: #a12025;
  transform: translateY(-1px);
}

.hero-qr {
  margin-top: 1.8rem;
}

.hero-qr img {
  width: 150px;
  height: 150px;
  border-radius: var(--radius);
  background: var(--umuwhite);
  padding: 6px;
  box-shadow: 0 2px 10px rgba(0,0,0,0.2);
}

.qr-label {
  font-size: 0.8rem;
  color: rgba(255,255,255,0.55);
  margin-top: 0.4rem;
}

/* --- Task Cards Grid (index) --- */
.section {
  max-width: 1100px;
  margin: 0 auto;
  padding: 3rem 2rem;
}

.section-title {
  font-size: 1.6rem;
  color: var(--umuteal);
  margin-bottom: 0.4rem;
  text-align: center;
}

.section-subtitle {
  color: var(--umutextmed);
  text-align: center;
  margin-bottom: 2rem;
  font-size: 1rem;
}

.task-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: 1.5rem;
}

.task-card {
  background: var(--umuwhite);
  border: 1px solid var(--umugraymed);
  border-radius: var(--radius-lg);
  padding: 1.8rem;
  transition: all 0.3s;
  display: flex;
  flex-direction: column;
  position: relative;
  overflow: hidden;
}

.task-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: var(--umured);
}

.task-card:hover {
  box-shadow: var(--shadow-lg);
  transform: translateY(-3px);
  border-color: var(--umuteallight);
}

.task-card .task-number {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  background: var(--umured);
  color: var(--umuwhite);
  font-weight: 700;
  font-size: 1rem;
  border-radius: 50%;
  margin-bottom: 0.8rem;
}

.task-card h3 {
  font-size: 1.15rem;
  color: var(--umuteal);
  margin-bottom: 0.4rem;
}

.task-card .tool-badge {
  display: inline-block;
  background: var(--umuteallight-bg);
  color: var(--umuteallight);
  font-size: 0.75rem;
  font-weight: 600;
  padding: 0.2rem 0.6rem;
  border-radius: 20px;
  margin-bottom: 0.6rem;
}

.task-card p {
  font-size: 0.9rem;
  color: var(--umutextmed);
  flex: 1;
  margin-bottom: 1rem;
}

.task-card .difficulty {
  font-size: 0.8rem;
  color: var(--umutextmed);
  margin-bottom: 0.8rem;
}

.task-card .difficulty .star-filled {
  color: var(--umured);
}

.task-card .btn {
  display: inline-block;
  text-align: center;
  padding: 0.55rem 1.2rem;
  background: var(--umuteal);
  color: var(--umuwhite);
  border-radius: 8px;
  font-size: 0.88rem;
  font-weight: 600;
  transition: background 0.2s;
}

.task-card .btn:hover {
  background: var(--umuteallight);
  color: var(--umuwhite);
}

/* --- Page Header (task pages) --- */
.page-header {
  background: linear-gradient(135deg, var(--umutealdark) 0%, var(--umuteal) 100%);
  color: var(--umuwhite);
  padding: 2.5rem 2rem 2rem;
  position: relative;
  overflow: hidden;
}

.page-header::before {
  content: '';
  position: absolute;
  top: -50px;
  right: -50px;
  width: 200px;
  height: 200px;
  background: var(--umuteallight);
  opacity: 0.1;
  border-radius: 50%;
}

.page-header-inner {
  max-width: 900px;
  margin: 0 auto;
  position: relative;
  z-index: 1;
}

.page-header .breadcrumb {
  font-size: 0.85rem;
  color: rgba(255,255,255,0.6);
  margin-bottom: 0.6rem;
}

.page-header .breadcrumb a {
  color: rgba(255,255,255,0.7);
}

.page-header .breadcrumb a:hover {
  color: var(--umuwhite);
}

.page-header h1 {
  font-size: 2rem;
  margin-bottom: 0.3rem;
}

.page-header .page-meta {
  display: flex;
  gap: 1.2rem;
  font-size: 0.88rem;
  color: var(--umugraymed);
  flex-wrap: wrap;
}

.page-header .page-meta span {
  display: flex;
  align-items: center;
  gap: 0.3rem;
}

/* --- Guide Content --- */
.guide-content {
  max-width: 860px;
  margin: 0 auto;
  padding: 2.5rem 2rem 4rem;
}

.guide-content h2 {
  font-size: 1.4rem;
  color: var(--umuteal);
  margin-top: 2.5rem;
  margin-bottom: 0.8rem;
  padding-bottom: 0.4rem;
  border-bottom: 2px solid var(--umured);
  display: inline-block;
}

.guide-content h3 {
  font-size: 1.1rem;
  color: var(--umuteal);
  margin-top: 1.8rem;
  margin-bottom: 0.5rem;
}

.guide-content p {
  margin-bottom: 1rem;
  color: var(--umutextdark);
}

.guide-content ul, .guide-content ol {
  margin-bottom: 1rem;
  padding-left: 1.5rem;
}

.guide-content li {
  margin-bottom: 0.4rem;
}

/* --- Step boxes --- */
.step {
  background: var(--umuwhite);
  border: 1px solid var(--umugraymed);
  border-left: 4px solid var(--umuteal);
  border-radius: var(--radius);
  padding: 1.4rem 1.6rem;
  margin-bottom: 1.5rem;
  position: relative;
}

.step-number {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  background: var(--umuteal);
  color: var(--umuwhite);
  font-weight: 700;
  font-size: 0.9rem;
  border-radius: 50%;
  margin-right: 0.6rem;
  flex-shrink: 0;
}

.step-header {
  display: flex;
  align-items: center;
  margin-bottom: 0.6rem;
}

.step-header h4 {
  font-size: 1.05rem;
  color: var(--umuteal);
}

.step p {
  margin-bottom: 0.5rem;
  margin-left: 2.5rem;
}

.step ul {
  margin-left: 2.5rem;
}

/* --- Screenshot placeholder --- */
.screenshot-placeholder {
  background: var(--umugray);
  border: 2px dashed var(--umugraymed);
  border-radius: var(--radius);
  padding: 2rem 1.5rem;
  text-align: center;
  margin: 1.2rem 0;
  color: var(--umutextmed);
  font-size: 0.88rem;
}

.screenshot-placeholder .icon {
  font-size: 2rem;
  margin-bottom: 0.4rem;
  opacity: 0.5;
}

.screenshot-placeholder .label {
  font-weight: 600;
  display: block;
  margin-bottom: 0.2rem;
  color: var(--umuteal);
}

/* Actual screenshot images */
.screenshot {
  display: block;
  margin: 1.2rem auto;
  border-radius: var(--radius);
  border: 1px solid var(--umugraymed);
  box-shadow: var(--shadow-sm);
  max-width: 100%;
}

/* Screenshot figures with caption */
figure.screenshot-img {
  margin: 1.4rem 0;
  text-align: center;
}

figure.screenshot-img img {
  display: block;
  max-width: 100%;
  border-radius: var(--radius);
  border: 1px solid var(--umugraymed);
  box-shadow: var(--shadow-sm);
  margin: 0 auto;
}

figure.screenshot-img figcaption {
  margin-top: 0.45rem;
  font-size: 0.82rem;
  color: var(--umutextmed);
  font-style: italic;
}

/* --- Info boxes --- */
.info-box {
  border-radius: var(--radius);
  padding: 1.2rem 1.4rem;
  margin: 1.2rem 0;
  font-size: 0.92rem;
}

.info-box.tip {
  background: var(--umuteallight-bg);
  border-left: 4px solid var(--umuteallight);
}

.info-box.warning {
  background: #fff8e1;
  border-left: 4px solid #f9a825;
}

.info-box.important {
  background: var(--umured-bg);
  border-left: 4px solid var(--umured);
}

.info-box.note {
  background: var(--umugray);
  border-left: 4px solid var(--umuteal);
}

.info-box strong {
  display: block;
  margin-bottom: 0.3rem;
}

/* --- Code blocks --- */
.code-block {
  background: var(--umutealdark);
  color: #e0e0e0;
  border-radius: var(--radius);
  padding: 1.2rem 1.4rem;
  margin: 1rem 0;
  font-family: 'Consolas', 'Fira Code', monospace;
  font-size: 0.85rem;
  overflow-x: auto;
  line-height: 1.6;
}

.code-block .comment {
  color: #6a9955;
}

.code-block .string {
  color: #ce9178;
}

.code-block .keyword {
  color: #569cd6;
}

/* --- Comparison table --- */
.comparison-table {
  width: 100%;
  border-collapse: collapse;
  margin: 1.2rem 0;
  font-size: 0.9rem;
}

.comparison-table th {
  background: var(--umuteal);
  color: var(--umuwhite);
  padding: 0.7rem 1rem;
  text-align: left;
  font-weight: 600;
}

.comparison-table td {
  padding: 0.6rem 1rem;
  border-bottom: 1px solid var(--umugraymed);
}

.comparison-table tr:nth-child(even) {
  background: var(--umugray);
}

.comparison-table tr:hover {
  background: var(--umuteallight-bg);
}

/* --- Footer --- */
.footer {
  background: var(--umutealdark);
  color: rgba(255,255,255,0.6);
  text-align: center;
  padding: 1.5rem 2rem;
  font-size: 0.85rem;
}

.footer a {
  color: rgba(255,255,255,0.8);
}

.footer strong {
  color: var(--umuwhite);
}

/* --- Task navigation at bottom of guide pages --- */
.task-nav {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  margin-top: 3rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--umugraymed);
}

.task-nav a {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.7rem 1.2rem;
  background: var(--umugray);
  border-radius: 8px;
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--umuteal);
  transition: all 0.2s;
}

.task-nav a:hover {
  background: var(--umuteallight-bg);
  color: var(--umuteallight);
}

/* --- Quick access box --- */
.quick-access {
  background: var(--umugray);
  border-radius: var(--radius-lg);
  padding: 1.5rem 2rem;
  margin: 2rem 0;
}

.quick-access h3 {
  color: var(--umuteal);
  margin-bottom: 0.8rem;
  font-size: 1rem;
}

.quick-access ul {
  list-style: none;
  padding: 0;
}

.quick-access li {
  margin-bottom: 0.3rem;
}

.quick-access a {
  font-size: 0.9rem;
}

/* --- Previous talks section --- */
.previous-talks {
  background: var(--umugray);
  max-width: 100%;
  padding: 3rem 2rem;
}

.previous-talks .section-title,
.previous-talks .section-subtitle {
  max-width: 1100px;
  margin-left: auto;
  margin-right: auto;
}

.talks-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 1rem;
  max-width: 1100px;
  margin: 0 auto;
}

.talk-card {
  display: flex;
  align-items: center;
  gap: 1rem;
  background: var(--umuwhite);
  border: 1px solid var(--umugraymed);
  border-radius: var(--radius);
  padding: 1rem 1.3rem;
  text-decoration: none;
  color: var(--umutextdark);
  transition: all 0.25s;
  box-shadow: var(--shadow-sm);
}

.talk-card:hover {
  border-color: var(--umuteallight);
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
  color: var(--umuteal);
}

.talk-icon {
  font-size: 1.8rem;
  flex-shrink: 0;
  opacity: 0.7;
}

.talk-card:hover .talk-icon {
  opacity: 1;
}

.talk-info h4 {
  font-size: 0.95rem;
  color: var(--umuteal);
  margin-bottom: 0.15rem;
  line-height: 1.3;
}

.talk-date {
  font-size: 0.78rem;
  color: var(--umutextmed);
}

/* --- Responsive --- */
@media (max-width: 768px) {
  .hero h1 {
    font-size: 1.8rem;
  }

  .navbar-inner {
    flex-direction: column;
    gap: 0.5rem;
  }

  .navbar-links {
    justify-content: center;
  }

  .task-grid,
  .talks-grid {
    grid-template-columns: 1fr;
  }

  .page-header h1 {
    font-size: 1.5rem;
  }

  .guide-content {
    padding: 1.5rem 1rem 3rem;
  }

  .step p, .step ul {
    margin-left: 0;
  }

  .task-nav {
    flex-direction: column;
  }
}

@media (max-width: 480px) {
  .navbar {
    padding: 0.5rem 1rem;
  }

  .navbar-links a {
    font-size: 0.7rem;
    padding: 0.25rem 0.4rem;
  }

  .hero {
    padding: 2.5rem 1rem 2rem;
  }

  .section {
    padding: 2rem 1rem;
  }
}