/* ==========================================================================
   custom.css
   Portfolio-specific components and visual presentation
   ========================================================================== */

/* ---------- Hero ---------- */
.hero {
  position: relative;
  isolation: isolate;
  display: grid;
  place-items: center;
  min-height: calc(100svh - var(--header-height));
  padding: clamp(3.5rem, 8vw, 7rem) 1rem;
  overflow: hidden;
  text-align: center;
  background:
    radial-gradient(circle at 50% 30%, var(--color-accent-soft), transparent 24rem),
    linear-gradient(135deg, var(--color-bg) 20%, var(--color-surface) 100%);
  border-bottom: 1px solid var(--color-border);
}

.hero::before,
.hero::after {
  content: "";
  position: absolute;
  z-index: -1;
  width: 22rem;
  aspect-ratio: 1;
  border-radius: 50%;
  filter: blur(5rem);
  opacity: 0.18;
  pointer-events: none;
}

.hero::before {
  top: -8rem;
  left: -8rem;
  background: var(--color-accent);
}

.hero::after {
  right: -9rem;
  bottom: -10rem;
  background: var(--color-accent-strong);
}

.hero-content {
  width: min(100%, 52rem);
  margin-inline: auto;
}

.hero h1 {
  margin-bottom: 0.6rem;
}

.profile-img {
  width: clamp(8.5rem, 18vw, 10.5rem);
  aspect-ratio: 1;
  margin: 0 auto 1.4rem;
  object-fit: cover;
  border: 0.28rem solid var(--color-accent);
  border-radius: 50%;
  box-shadow:
    0 0 0 0.5rem var(--color-accent-soft),
    var(--shadow-lg);
  transition:
    transform var(--transition-base),
    box-shadow var(--transition-base);
}

.profile-img:hover {
  transform: scale(1.025);
  box-shadow:
    0 0 0 0.65rem var(--color-accent-soft),
    0 0 2rem rgba(77, 171, 247, 0.36),
    var(--shadow-lg);
}

.hero-subtitle {
  max-width: 46rem;
  margin: 0 auto;
  color: var(--color-text-muted);
  font-size: clamp(1rem, 2vw, 1.25rem);
  font-weight: 500;
  text-wrap: balance;
}

.social-icons {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: center;
  gap: 0.75rem;
  margin: 1.45rem 0 0;
  padding: 0;
  list-style: none;
}

.social-icons li {
  margin: 0;
}

.social-icons a {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 2.75rem;
  height: 2.75rem;
  color: var(--color-text);
  font-size: 1.35rem;
  background: color-mix(in srgb, var(--color-surface-2) 85%, transparent);
  border: 1px solid var(--color-border);
  border-radius: 50%;
  transition:
    color var(--transition-fast),
    background-color var(--transition-fast),
    border-color var(--transition-fast),
    transform var(--transition-base),
    box-shadow var(--transition-base);
}

.social-icons a:hover {
  color: var(--color-accent);
  background: var(--color-accent-soft);
  border-color: var(--color-border-strong);
  box-shadow: 0 0 0 0.3rem var(--color-accent-soft);
  transform: translateY(-0.15rem);
}

/* ---------- Section headings ---------- */
.content-container h2 {
  display: inline-block;
  margin-bottom: 0.45rem;
}

.content-container h2::after {
  content: "";
  display: block;
  width: 3.2rem;
  height: 0.22rem;
  margin-top: 0.5rem;
  border-radius: var(--radius-pill);
  background: var(--color-accent);
}

/* ---------- About ---------- */
#about p {
  max-width: 66rem;
}

#about h3 {
  margin-top: 1.6rem;
  color: var(--color-accent);
}

/* ---------- Shared cards ---------- */
.education-card,
.research-highlight,
.objective-card,
.area-card,
.project-card,
.publication-card,
.experience-card,
.skill-card {
  min-width: 0;
  padding: 1.25rem;
  background: var(--color-surface-2);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
  transition:
    transform var(--transition-base),
    border-color var(--transition-base),
    box-shadow var(--transition-base),
    background-color var(--transition-base);
}

.education-card:hover,
.objective-card:hover,
.area-card:hover,
.project-card:hover,
.publication-card:hover,
.experience-card:hover,
.skill-card:hover {
  transform: translateY(-0.18rem);
  border-color: var(--color-border-strong);
  box-shadow: var(--shadow-md);
  background: var(--color-surface-hover);
}

.education-card + .education-card,
.publication-card + .publication-card,
.experience-card + .experience-card {
  margin-top: 1rem;
}

.education-card h3,
.publication-card h3,
.project-card h4,
.area-card h5,
.objective-card h5 {
  margin-bottom: 0.4rem;
}

.institution,
.date,
.authors {
  margin-bottom: 0.4rem;
}

.date {
  color: var(--color-accent);
  font-weight: 700;
}

/* ---------- Research ---------- */
.research-highlight {
  padding: clamp(1.15rem, 3vw, 2rem);
}

.thesis-title {
  margin-bottom: 1.4rem;
  padding: 1rem 1.1rem;
  background: var(--color-accent-soft);
  border-left: 0.25rem solid var(--color-accent);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
}

.highlighted-text {
  margin-bottom: 0.45rem;
  color: var(--color-heading);
  font-size: 1.05rem;
  font-weight: 700;
}

.research-highlight > h4 {
  margin-top: 1.8rem;
  color: var(--color-accent);
}

.objectives-grid,
.research-areas,
.projects-grid {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: 1rem;
}

.objective-card {
  grid-column: 1 / -1;
}

.area-card {
  grid-column: span 6;
}

.area-card ul,
.objective-card ul,
.applications ul,
.methodology ul {
  margin-bottom: 0;
}

/* ---------- Experience ---------- */
#experience > .content > ol {
  display: grid;
  gap: 1rem;
  padding-left: 0;
  list-style: none;
  counter-reset: experience;
}

#experience > .content > ol > li {
  position: relative;
  padding: 1.2rem 1.2rem 1.2rem 3.35rem;
  background: var(--color-surface-2);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
  counter-increment: experience;
}

#experience > .content > ol > li::before {
  content: counter(experience);
  position: absolute;
  top: 1.05rem;
  left: 1rem;
  display: grid;
  place-items: center;
  width: 1.75rem;
  height: 1.75rem;
  color: #ffffff;
  font-size: 0.82rem;
  font-weight: 800;
  background: var(--color-accent);
  border-radius: 50%;
}

#experience li ul {
  margin-top: 0.6rem;
  margin-bottom: 0;
}

/* For the recommended chronological HTML structure. */
.experience-list {
  display: grid;
  gap: 1rem;
}

.experience-card {
  position: relative;
  padding-left: 1.5rem;
  border-left: 0.24rem solid var(--color-accent);
}

.experience-card .experience-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.35rem 0.8rem;
  margin-bottom: 0.75rem;
  color: var(--color-text-muted);
}

.experience-card ul {
  margin-bottom: 0;
}

/* ---------- Projects ---------- */
.project-category + .project-category {
  margin-top: 2.1rem;
}

.project-category > h3 {
  margin-bottom: 1rem;
  color: var(--color-accent);
}

.project-card {
  grid-column: span 4;
  display: flex;
  flex-direction: column;
  align-items: flex-start;
}

.project-card p {
  flex-grow: 1;
  color: var(--color-text-muted);
}

.project-card .github-link {
  margin-top: auto;
}

/* ---------- Publications ---------- */
.publication-title {
  color: var(--color-heading);
  font-weight: 700;
}

.publication-card .abstract {
  margin-bottom: 0;
  color: var(--color-text-muted);
}

/* ---------- Skills ---------- */
#skills ul {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0.8rem;
  padding: 0;
  list-style: none;
}

#skills li {
  margin: 0;
  padding: 1rem;
  background: var(--color-surface-2);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
}

#skills li strong {
  color: var(--color-accent);
}

/* ---------- Contact ---------- */
#contact {
  text-align: center;
}

#contact .content {
  max-width: 48rem;
}

/* ---------- Footer ---------- */
.footer {
  margin-top: var(--space-6);
  padding: 2rem 1rem;
  color: var(--color-text);
  text-align: center;
  background:
    linear-gradient(135deg, var(--color-bg) 20%, var(--color-surface) 100%);
  border-top: 1px solid var(--color-border);
}

.footer-content {
  width: min(100%, var(--page-width));
  margin-inline: auto;
}

.footer-content p {
  margin: 0;
  color: var(--color-text-muted);
}

.footer-social-icons {
  margin-top: 0.8rem;
}

.footer-social-icons .social-icons {
  margin-top: 0;
}

.footer-social-icons .social-icons a {
  width: 2.5rem;
  height: 2.5rem;
  font-size: 1.15rem;
}

/* ---------- Progressive reveal ---------- */
.reveal {
  opacity: 0;
  transform: translateY(1rem);
  transition:
    opacity 520ms ease,
    transform 520ms ease;
}

.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ---------- Responsive components ---------- */
@media (max-width: 64rem) {
  .project-card {
    grid-column: span 6;
  }
}

@media (max-width: 48rem) {
  .area-card,
  .project-card {
    grid-column: 1 / -1;
  }

  #skills ul {
    grid-template-columns: 1fr;
  }

  .research-highlight,
  .education-card,
  .publication-card,
  .project-card {
    padding: 1.05rem;
  }
}

@media (max-width: 36rem) {
  .hero {
    min-height: calc(92svh - var(--header-height));
    padding-block: 3.5rem;
  }

  .social-icons {
    gap: 0.55rem;
  }

  .social-icons a {
    width: 2.55rem;
    height: 2.55rem;
    font-size: 1.2rem;
  }

  #experience > .content > ol > li {
    padding: 1rem;
  }

  #experience > .content > ol > li::before {
    display: none;
  }
}