/* ==========================================================================
   style.css - César Landín, academic site
   Sections: 1 tokens | 2 base | 3 nav | 4 intro | 5 cards | 6 thumb effects
             7 CV | 8 footer | 9 responsive | 10 reduced motion
   ========================================================================== */


/* ==========================================================================
   1. Design tokens (light default; dark via OS preference or data-theme)
   ========================================================================== */
:root {
  --bg: #ffffff;
  --text: #1f2328;
  --heading: #002145;
  --link: #1c4f8c;
  --link-hover: #002145;
  --muted: #5a6270;
  --rule: #d9dde3;
  --toggle-bg: #f1f3f6;
  --thumb-neutral: #eef0f3;
  --accent-soft: rgba(28, 79, 140, 0.08);
  --card-shadow: 0 1px 3px rgba(0, 33, 69, 0.08);
  --font: 'Source Serif 4', Georgia, 'Times New Roman', serif;
}

/* Dark: follows the OS unless the user has explicitly chosen light */
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #0f1722;
    --text: #e2e6eb;
    --heading: #c9dcf2;
    --link: #8fbbe8;
    --link-hover: #c9dcf2;
    --muted: #9aa5b3;
    --rule: #2c3644;
    --toggle-bg: #1b2533;
    --thumb-neutral: #d9dee5;
    --accent-soft: rgba(143, 187, 232, 0.12);
    --card-shadow: 0 1px 3px rgba(0, 0, 0, 0.35);
  }
}

/* Dark: explicit user choice */
:root[data-theme="dark"] {
  --bg: #0f1722;
  --text: #e2e6eb;
  --heading: #c9dcf2;
  --link: #8fbbe8;
  --link-hover: #c9dcf2;
  --muted: #9aa5b3;
  --rule: #2c3644;
  --toggle-bg: #1b2533;
  --thumb-neutral: #d9dee5;
  --accent-soft: rgba(143, 187, 232, 0.12);
  --card-shadow: 0 1px 3px rgba(0, 0, 0, 0.35);
}


/* ==========================================================================
   2. Base
   ========================================================================== */
*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  font-family: var(--font);
  font-size: 17px;
  line-height: 1.6;
  background: var(--bg);
  color: var(--text);
  overflow-wrap: break-word;
  transition: background-color 0.25s ease, color 0.25s ease;
  /* Sticky footer: the page is a column at least as tall as the window and
     <main> absorbs the spare height, so the footer sits at the bottom of
     short pages (e.g. Home) instead of floating mid-screen. */
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  min-height: 100dvh;
}

main {
  flex: 1 0 auto;
  width: 100%;
}

img {
  max-width: 100%;
}

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

a:hover {
  color: var(--link-hover);
  text-decoration: underline;
}

:focus-visible {
  outline: 2px solid var(--link);
  outline-offset: 2px;
}

.container {
  max-width: 860px;
  margin: 0 auto;
  padding: 0 16px;
}

.section-title {
  margin: 2rem 0 0.5rem;
  font-size: 1.6rem;
  font-weight: 600;
  line-height: 1.25;
  color: var(--heading);
}

.subsection-title {
  margin: 1.75rem 0 0.25rem;
  font-size: 1.2rem;
  font-weight: 600;
  line-height: 1.3;
  color: var(--heading);
}

.page-lead {
  margin: 0 0 1rem;
  color: var(--muted);
}


/* ==========================================================================
   3. Navigation
   ========================================================================== */
.site-nav {
  border-bottom: 1px solid var(--rule);
}

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding-top: 0.9rem;
  padding-bottom: 0.9rem;
}

.site-name {
  font-size: 1.6rem;
  font-weight: 600;
  line-height: 1.2;
  color: var(--heading);
}

.site-name:hover {
  color: var(--heading);
  text-decoration: none;
}

.nav-right {
  display: flex;
  align-items: center;
  gap: 1.1rem;
}

.tabs {
  display: flex;
  gap: 1.4rem;
}

.tabs a {
  padding: 0.25rem 0;
  color: var(--muted);
  border-bottom: 2px solid transparent;
}

.tabs a:hover {
  color: var(--heading);
  text-decoration: none;
}

.tabs a[aria-current="page"] {
  color: var(--heading);
  border-bottom-color: var(--heading);
}

.theme-toggle {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 2.25rem;
  height: 2.25rem;
  padding: 0;
  border: 0;
  border-radius: 50%;
  background: var(--toggle-bg);
  color: var(--heading);
  font: inherit;
  font-size: 0.95rem;
  line-height: 1;
  cursor: pointer;
  -webkit-appearance: none;
  appearance: none;
  transition: background-color 0.25s ease, color 0.25s ease;
}

.theme-toggle:hover {
  color: var(--link);
}

/* Light shows the moon (switch to dark); dark shows the sun */
.theme-toggle .fa-sun { display: none; }
.theme-toggle .fa-moon { display: inline-block; }

:root[data-theme="dark"] .theme-toggle .fa-sun { display: inline-block; }
:root[data-theme="dark"] .theme-toggle .fa-moon { display: none; }
:root[data-theme="light"] .theme-toggle .fa-sun { display: none; }
:root[data-theme="light"] .theme-toggle .fa-moon { display: inline-block; }


/* ==========================================================================
   4. Intro and contact icons
   ========================================================================== */
.intro {
  display: flex;
  align-items: flex-start;
  gap: 2rem;
  padding: 2rem 0;
  /* no bottom rule: Home shows only the intro, and the footer has its own rule */
}

.intro-media {
  flex-shrink: 0;
  width: 180px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.8rem;
}

.intro-photo {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 4 / 5;
  object-fit: cover;
  object-position: 50% 50%;
  border-radius: 8px;
}

/* No padding-top: the first line of text lines up with the top of the photo */
.intro-text {
  min-width: 0;
}

.intro-text > :first-child {
  margin-top: 0;
}

.intro-text p {
  margin: 0 0 0.9rem;
}

.affiliation {
  color: var(--muted);
  font-size: 0.95rem;
  line-height: 1.25;
}

.contact-icons {
  display: flex;
  flex-wrap: wrap;
  gap: 0.9rem;
  font-size: 1.35rem;
  line-height: 1;
}

.contact-icons a {
  display: inline-block;
  color: var(--link);
  transition: color 0.2s ease, transform 0.2s ease;
}

.contact-icons a:hover {
  color: var(--link-hover);
  text-decoration: none;
  transform: translateY(-2px);
}


/* ==========================================================================
   5. Cards (papers and datasets)
   ========================================================================== */
.card {
  display: flex;
  gap: 1.25rem;
  padding: 1.25rem 0;
  border-bottom: 1px solid var(--rule);
}

.card-thumb {
  flex-shrink: 0;
  width: 125px;
  height: 125px;
  overflow: hidden;
  border: 1px solid var(--rule);
  border-radius: 6px;
  box-shadow: var(--card-shadow);
  /* The SVGs are transparent: the container supplies the backdrop. Rest state
     is neutral; --thumb-tint (set inline per card) is the hover/zoom colour.
     Two faint radial highlights keep the panel from looking flat. */
  background-color: var(--thumb-neutral);
  background-image:
    radial-gradient(circle at 80% 15%, rgba(255, 255, 255, 0.55) 0 18%, transparent 19%),
    radial-gradient(circle at 10% 90%, rgba(0, 0, 0, 0.04) 0 22%, transparent 23%);
  transition: background-color 0.35s ease;
}

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

.card-body {
  flex: 1;
  min-width: 0;
}

.card-title {
  margin: 0 0 0.3rem;
  font-size: 1.1rem;
  font-weight: 600;
  line-height: 1.35;
  color: var(--heading);
}

.card-authors {
  margin: 0 0 0.35rem;
  font-style: italic;
  color: var(--muted);
}

.card-status {
  margin: 0 0 0.5rem;
}

.badge {
  display: inline-block;
  padding: 0.05rem 0.55rem;
  border-radius: 999px;
  background: var(--accent-soft);
  color: var(--link);
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

.card-desc {
  margin: 0 0 0.6rem;
  font-size: 0.97rem;
}

.card-links {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.pill {
  display: inline-block;
  margin: 0;
  padding: 0.2rem 0.8rem;
  border: 1px solid transparent;
  border-radius: 999px;
  background: var(--accent-soft);
  color: var(--link);
  font: inherit;
  font-size: 0.88rem;
  line-height: 1.5;
  text-decoration: none;
  cursor: pointer;
  -webkit-appearance: none;
  appearance: none;
  transition: background-color 0.2s ease, color 0.2s ease;
}

.pill:hover {
  background: var(--link);
  color: var(--bg);
  text-decoration: none;
}

.pill--primary {
  background: var(--link);
  color: var(--bg);
}

.pill--primary:hover {
  background: var(--link-hover);
  color: var(--bg);
}

.pill--disabled,
.pill--disabled:hover {
  background: transparent;
  border: 1px dashed var(--rule);
  color: var(--muted);
  cursor: default;
}

.abstract {
  margin-top: 0.8rem;
  padding: 1rem;
  border-left: 3px solid var(--link);
  border-radius: 4px;
  background: var(--accent-soft);
  font-size: 0.95rem;
  line-height: 1.6;
}

.abstract[hidden] {
  display: none;
}

.abstract p {
  margin: 0;
}


/* ==========================================================================
   6. Thumbnail effects (switch: body[data-thumb-effect])
   ========================================================================== */
/* Default is accent (set on each page's <body>). */
/* grayscale: grey image on a neutral panel; colour image on the
   card's tint on hover/focus */
body[data-thumb-effect="grayscale"] .card-thumb img {
  filter: grayscale(100%);
  transition: filter 0.35s ease;
}

body[data-thumb-effect="grayscale"] .card:hover .card-thumb img,
body[data-thumb-effect="grayscale"] .card:focus-within .card-thumb img {
  filter: grayscale(0);
}

body[data-thumb-effect="grayscale"] .card:hover .card-thumb,
body[data-thumb-effect="grayscale"] .card:focus-within .card-thumb {
  background-color: var(--thumb-tint, var(--toggle-bg));
}

/* zoom: image always in colour on the tint; zooms slightly on hover
   (.card-thumb already clips overflow) */
body[data-thumb-effect="zoom"] .card-thumb {
  background-color: var(--thumb-tint, var(--toggle-bg));
}

body[data-thumb-effect="zoom"] .card-thumb img {
  transition: transform 0.35s ease;
}

body[data-thumb-effect="zoom"] .card:hover .card-thumb img {
  transform: scale(1.08);
}

/* accent: image always in colour; only the panel changes from neutral grey
   to the card's tint on hover/focus */
body[data-thumb-effect="accent"] .card:hover .card-thumb,
body[data-thumb-effect="accent"] .card:focus-within .card-thumb {
  background-color: var(--thumb-tint, var(--toggle-bg));
}


/* ==========================================================================
   7. CV page
   ========================================================================== */
.cv-actions {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.9rem;
  margin: 0.5rem 0 1.25rem;
}

.cv-updated {
  color: var(--muted);
  font-size: 0.9rem;
}

.cv-embed {
  max-width: 100%;
}

.cv-embed iframe {
  display: block;
  width: 100%;
  height: 85vh;
  min-height: 600px;
  border: 1px solid var(--rule);
  border-radius: 6px;
}


/* ==========================================================================
   8. Footer
   ========================================================================== */
.site-footer {
  margin-top: 3rem;
  padding: 1.5rem 0;
  border-top: 1px solid var(--rule);
  color: var(--muted);
  font-size: 0.88rem;
  text-align: center;
}

.site-footer p {
  margin: 0;
}


/* ==========================================================================
   9. Responsive (below 700px)
   ========================================================================== */
@media (max-width: 699px) {
  /* Name on the first line; tabs + toggle on the second */
  .nav-inner {
    flex-wrap: wrap;
    row-gap: 0.4rem;
  }

  .nav-right {
    flex: 1 1 100%;
    justify-content: space-between;
  }

  /* Intro stacks, photo centred above the text */
  .intro {
    flex-direction: column;
    align-items: stretch;
    gap: 1.25rem;
  }

  .intro-media {
    align-self: center;
  }

  .card {
    gap: 0.9rem;
  }

  .card-thumb {
    width: 80px;
    height: 80px;
  }

  .cv-embed {
    display: none;
  }
}


/* ==========================================================================
   10. Reduced motion
   ========================================================================== */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    transition: none !important;
    animation: none !important;
  }

  .contact-icons a:hover,
  body[data-thumb-effect="zoom"] .card:hover .card-thumb img {
    transform: none !important;
  }
}