:root {
  color-scheme: light;
  font-family: "Helvetica Neue", Helvetica, Arial, sans-serif;
  --bg: #fbfbf8;
  --text: #000000;
  --muted: #6d6967;
  --card: #ffffff;
  --border: #EC6581;
  --accent: rgb(220, 0, 45);
  --header-offset: 0px;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  border: 0;
}

.page-wrapper {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  padding: 1rem 1.5rem;
  background: var(--bg);
  border-bottom: 1px solid rgba(0, 0, 0, 0.03);
  box-shadow: 0 2px 15px rgba(0, 0, 0, 0.12);  
  backdrop-filter: blur(8px);
}

.site-header__inner {
  max-width: 70rem;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.site-header__content {
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
  text-align: left;
}

.site-header h1 {
  margin: 0;
  font-size: clamp(1.4rem, 2.5vw, 2.2rem);
}

.site-header p {
  margin: 0;
  max-width: 32rem;
  color: var(--muted);
  line-height: 1.4;
}

.site-header__extra {
  margin-top: 0.25rem;
}

.inline-link {
  color: var(--accent);
  font-weight: 600;
  text-decoration: none;
}

.inline-link:hover,
.inline-link:focus-visible {
  text-decoration: underline;
}

main {
  width: min(70rem, 100%);
  margin: 0 auto;
  padding: 1rem 1.5rem 3rem;
  flex: 1;
}

.muted {
  margin: 0 0 1.5rem;
  max-width: 40rem;
  color: var(--muted);
  line-height: 1.5;
}

.notice {
  border: 1px solid var(--border);
  border-radius: 0.75rem;
  padding: 1rem 1.25rem;
  background: #fff6f3;
  color: var(--text);
  margin: 1.5rem 0;
}

.notice--warning {
  border-color: var(--accent);
}

.notice strong {
  color: var(--accent);
}

.notice__list {
  margin: 0.5rem 0 0;
  padding-left: 1.25rem;
  color: var(--text);
}

.project-section {
  margin-top: 2.5rem;
}

.project-section:first-of-type {
  margin-top: 1.5rem;
}

.project-section__header {
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
}

.project-section__title {
  margin: 0;
  font-size: 1.6rem;
}

.project-section__intro {
  margin: 0;
}

.project-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(30rem, 1fr));
  gap: 1.5rem;
  list-style: none;
  padding: 0;
  margin: 2rem 0 0;
}

.past-projects {
  margin: 1rem auto;
  max-width: 48rem;
  padding-left: 1.25rem;
  display: flex;
  flex-direction: column;
}

.past-project__title {
  margin: 0;
  font-size: 1.05rem;
  font-weight: 600;
}

.past-project__title a {
  color: var(--text);
  text-decoration: underline;
}

.past-project__title a:hover,
.past-project__title a:focus-visible {
  color: var(--accent);
  text-decoration: underline;
}

.past-project__meta {
  margin: 0.1rem 0 0rem;
  color: var(--text);
  font-size: 0.95rem;
}

.tag-filter {
  display: flex;
  gap: 0.5rem;
  flex-wrap: wrap;
  margin-top: 1.5rem;
}

.tag-filter__btn {
  border: 1px solid var(--border);
  background: #fff;
  color: var(--text);
  padding: 0.35rem 0.9rem;
  border-radius: 999px;
  cursor: pointer;
  font-size: 0.95rem;
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  transition: all 0.2s ease;
}

.tag-filter__btn:hover,
.tag-filter__btn:focus-visible {
  border-color: var(--accent);
  color: var(--accent);
}

.tag-filter__btn.is-active {
  background: var(--accent);
  color: #fff;
  border-color: var(--accent);
}

.project-card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 0.75rem;
  padding: 1.25rem;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  box-shadow: 0 10px 30px rgba(15, 17, 21, 0.06);
  scroll-margin-top: calc(var(--header-offset) + 1rem);
  transition: box-shadow 0.3s ease, border-color 0.3s ease;
}

.project-card:target {
  animation: cardHighlight 1.4s ease-out forwards;
}

@keyframes cardHighlight {
  0% {
    background: var(--card);
    box-shadow: 0 10px 30px rgba(15, 17, 21, 0.06);
  }
  20% {
    background: rgba(198, 40, 40, 0.1);
    box-shadow: 0 14px 45px rgba(198, 40, 40, 0.25);
  }
  60% {
    background: rgba(198, 40, 40, 0.08);
    box-shadow: 0 12px 38px rgba(198, 40, 40, 0.2);
  }
  100% {
    background: var(--card);
    box-shadow: 0 10px 30px rgba(15, 17, 21, 0.06);
  }
}

.project-card.is-hidden {
  display: none;
  transition: opacity 0.2s ease;
}

.project-card.is-unavailable {
  opacity: 0.53;
  filter: grayscale(0.85);
}

.project-card h2 {
  margin: 0;
  font-size: 1.35rem;
  color: var(--text);
}

.project-card p {
  margin: 0;
  line-height: 1.5;
  color: var(--text);
}

.project-card__header {
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
}

.project-card__supervisor {
  font-size: 0.95rem;
}

.project-card__supervisor-link a {
  color: var(--text);
}

.project-card__supervisor a {
  color: var(--text);
  text-decoration: none;
}


.project-card__supervisor a:hover,
.project-card__supervisor a:focus-visible {
  text-decoration: underline;
}

.project-card__short {
  font-weight: 600;
  color: var(--text);
}

.project-card__long {
  margin-top: 0.5rem;
  color: var(--text);
  line-height: 1.6;
}

.project-card__long p {
  margin-top: 0.6rem;
  text-indent: 0.1rem;
}
.project-card__long[hidden] {
  display: none;
}

.project-card__details {
  margin-top: 0.5rem;
}

.details-toggle {
  border: none;
  background: none;
  color: var(--accent);
  font-weight: 600;
  cursor: pointer;
  padding: 0;
  display: inline-flex;
  align-items: center;
  gap: 0.25rem;
}

.details-toggle::after {
  content: "▾";
  font-size: 0.85rem;
  transition: transform 0.2s ease;
}

.details-toggle[aria-expanded="true"]::after {
  transform: rotate(-180deg);
}

.project-card__availability {
  margin-top: 0.25rem;
}

.availability {
  display: inline-flex;
  align-items: center;
  padding: 0.2rem 0.75rem;
  font-size: 0.85rem;
}

.availability--open {
  color: var(--text);
  border-color: var(--border);
}

.availability--closed {
  color: var(--muted);
  background: #f1f1f1;
  border-radius: 999px;
}

.tag-list {
  display: flex;
  flex-wrap: wrap;
  gap: 0.35rem;
  margin: 0;
  padding: 0;
  list-style: none;
}

.tag-list li {
  list-style: none;
}

.tag-chip {
  border: 1px dashed var(--border);
  border-radius: 999px;
  background: transparent;
  color: var(--text);
  font-size: 0.85rem;
  padding: 0.17rem 0.55rem;
  cursor: pointer;
}

.tag-chip:hover,
.tag-chip:focus-visible {
  border-color: var(--accent);
  color: var(--accent);
}

.site-footer {
  background: var(--accent);
  color: var(--bg);
  text-align: right;
  padding: 1rem 1.5rem;
  font-size: 0.95rem;
}

.site-footer a {
  color: #fff;
  text-decoration: none;
}

.site-header__nav {
  display: flex;
  justify-content: flex-end;
  gap: 0.75rem;
  flex-wrap: wrap;
}

.site-header__toggle {
  display: none;
}

.site-header__menu-toggle {
  display: none;
  flex-direction: column;
  gap: 0.25rem;
  width: 2.25rem;
  padding: 0.35rem 0.5rem;
  border: 1px dashed var(--border);
  border-radius: 999px;
  background: transparent;
  cursor: pointer;
  transition: all 0.2s ease;
}

.site-header__menu-toggle span {
  display: block;
  height: 2px;
  background: var(--text);
  border-radius: 2px;
  transition: transform 0.2s ease, opacity 0.2s ease;
}

.site-header__menu-toggle.is-active,
.site-header__toggle:checked ~ .site-header__menu-toggle {
  border-color: var(--accent);
  background: rgba(198, 40, 40, 0.08);
}

.site-nav__link {
  color: var(--text);
  text-decoration: none;
  font-weight: 600;
  padding: 0.25rem 0.5rem;
  border-radius: 0.35rem;
  transition: color 0.2s ease, background 0.2s ease;
}

.site-nav__link:hover,
.site-nav__link:focus-visible {
  color: var(--accent);
}

.site-nav__link.is-active {
  background: rgba(198, 40, 40, 0.12);
  color: var(--accent);
}

@media (max-width: 640px) {
  .site-header {
    padding: 0.5rem 1rem;
  }

  .site-header__inner {
    flex-direction: column;
    align-items: flex-start;
    gap: 0.5rem;
  }

  .site-header__extra {
    display: none;
  }

  .site-header__menu-toggle {
    display: flex;
  }

  .site-header__nav {
    width: 100%;
    flex-direction: column;
    align-items: flex-start;
    gap: 0.5rem;
    border: 1px solid rgba(0, 0, 0, 0.15);
    border-radius: 0.3rem;
    background: #fff;
    padding: 0.75rem;
    box-shadow: 0 12px 40px rgba(0, 0, 0, 0.1);
    display: none;
  }

  .site-header__toggle:checked ~ .site-header__menu-toggle span {
    transform: none;
    opacity: 1;
  }

  .site-header__toggle:checked ~ .site-header__nav {
    display: flex;
  }

  .site-header h1 {
    font-size: 1.3rem;
  }

  .site-header p {
    font-size: 0.9rem;
  }
}