/* ========================================
   1. FONTS
   ======================================== */

@font-face {
  font-family: 'Inter';
  src: url('assets/fonts/Inter-Variable.woff2') format('woff2');
  font-weight: 100 800;
  font-style: normal;
  font-display: swap;
}

/* ========================================
   2. DESIGN TOKENS
   ======================================== */

:root {
  --font-large: clamp(22px, 1.375rem + 1.67vw, 42px);
  --font-medium: clamp(20px, 1.25rem + 1vw, 32px);
  --font-small: clamp(18px, 1.125rem + 0.5vw, 24px);
  --font-xsmall: clamp(15px, 0.9375rem + 0.42vw, 20px);

  --space-card: 56px;
  --space-element: 32px;
  --space-bar: 32px;
  --space-inline: 56px;
  --space-gap: 2px;

  --radius-card: 16px;
  --radius-small: 8px;

  --green-lite: #DCF9EF;
  --green-main: #1E9A73;
  --green-dark: #096f4f;
  --green-deep: #0C4530;

  --color-01-lite: #ffd88a;
  --color-01-dark: #7c5403;
  --color-02-lite: #cbd0ff;
  --color-02-dark: #454e99;
  --color-03-lite: #E8C0E1;
  --color-03-dark: #752466;
}

/* ========================================
   3. RESET / BASE STYLES
   ======================================== */

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

body {
  font-family: 'Inter', sans-serif;
  line-height: 1.6;
  color: var(--green-dark);
  background-color: var(--green-main);
  overflow-wrap: break-word;
}

/* ========================================
   4. LAYOUT
   ======================================== */

.skip-link {
  position: absolute;
  top: -100%;
  left: 1rem;
  padding: 0.5rem 1rem;
  background-color: var(--green-dark);
  color: var(--green-lite);
  text-decoration: none;
  border-radius: var(--radius-small);
  z-index: 100;
  transition: transform 0.2s ease;
}

.skip-link:hover,
.skip-link:focus {
  top: 1rem;
  transform: scale(1.05);
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 16px;
}

/* Grid */
.grid-container {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-gap);
}

main .grid-container {
  padding-bottom: 0;
}

.footer .grid-container {
  padding-top: var(--space-gap);
  padding-bottom: var(--space-gap);
}

.grid-full {
  grid-column: 1 / -1;
}

/* ========================================
   5. TYPOGRAPHY
   ======================================== */

h1 {
  font-size: var(--font-large);
  line-height: 1.25;
  font-weight: 200;
}

h2 {
  font-size: var(--font-medium);
  line-height: 1.35;
  font-weight: 300;
}

h3 {
  font-size: var(--font-small);
  line-height: 1.6;
  font-weight: 300;
}

p {
  font-size: var(--font-xsmall);
  line-height: 1.5;
  font-weight: 300;
}

/* ========================================
   6. COMPONENTS — Cards
   ======================================== */

/* Base card */
.card {
  border-radius: var(--radius-card);
  padding: var(--space-card);
  overflow: hidden;
  background-color: var(--green-lite);
  color: var(--green-dark);
  word-break: break-word;
}

/* Card variants */
.card.card-image {
  padding: 0;
  position: relative;
  aspect-ratio: 2 / 1;
  overflow: hidden;
}

.card-image.topic-01::before,
.card-image.topic-02::before,
.card-image.topic-03::before,
.card-image.topic-green::before {
  content: '';
  position: absolute;
  inset: 0;
  background-color: currentColor;
  mix-blend-mode: multiply;
  opacity: 0.9;
  pointer-events: none;
  z-index: 1;
}

.card-image.topic-01 {
  color: var(--color-01-lite);
}

.card-image.topic-02 {
  color: var(--color-02-lite);
}

.card-image.topic-03 {
  color: var(--color-03-lite);
}

.card-image.topic-green {
  color: var(--green-main);
}

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

.card-image.topic-01 img,
.card-image.topic-02 img,
.card-image.topic-03 img,
.card-image.topic-green img {
  filter: grayscale(1) contrast(1.3);
}

.card-image.topic-01 img {
  object-position: center 30%;
}

.card-image.topic-02 img {
  object-position: center 35%;
}

.card-image--index-1 img {
  object-position: center 65%;
}

.card-image--index-2 img {
  object-position: center 55%;
}

.image-credit {
  position: absolute;
  bottom: 0px;
  right: 24px;
  background-color: rgba(0, 0, 0, 0.6);
  color: var(--green-lite);
  font-size: calc(var(--font-xsmall)*0.6);
  font-weight: 300;
  padding: 4px 8px;
  border-radius: var(--radius-small) var(--radius-small) 0 0;
  line-height: 1;
  white-space: nowrap;
}

.card-text {
  padding: var(--space-card);
  padding-bottom: calc(var(--space-card) * 2);
}

.card-text p {
  max-width: 50rem;
}

.card-text p + p {
  margin-top: 1em;
}

.highlight-card > h1,
.highlight-card > h2 {
  max-width: 56rem;
}

.sub-topic-section {
  display: flex;
  flex-direction: column;
  gap: var(--space-element);
  padding: var(--space-element) var(--space-inline);
}

.sub-topic-section > h1 {
  font-size: var(--font-large);
  font-weight: 300;
  display: flex;
  justify-content: space-between;
  align-items: baseline;
}

.sub-topic-section__number {
  font-weight: 200;
}

.sub-topic-section .video-card {
  margin-left: calc(-1 * var(--space-inline) + 4px);
  margin-right: calc(-1 * var(--space-inline) + 4px);
  margin-bottom: calc(-1 * var(--space-element) + 4px);
  border-radius: calc(var(--radius-card) - 4px);
}

.sub-topic-section .video-card:has(+ .link-card) {
  margin-bottom: calc(-1 * var(--space-element) + 4px);
}

.sub-topic-section .link-card {
  margin-left: calc(-1 * var(--space-inline) + 4px);
  margin-right: calc(-1 * var(--space-inline) + 4px);
  margin-bottom: calc(-1 * var(--space-element) + 4px);
  border-radius: calc(var(--radius-card) - 4px);
}


.highlight-card--section {
  background-color: var(--green-dark);
  color: var(--green-lite);
  padding: var(--space-card) calc(var(--space-card)*2);
  text-align: center;
}

.card-compact {
  padding: var(--space-element) var(--space-card);
}

.card-compact p .institution {
  font-weight: 200;
}

/* Link card */
.link-card {
  background-color: var(--green-dark);
  color: var(--green-lite);
  display: flex;
  justify-content: space-between;
  align-items: center;
  text-decoration: none;
  font-size: var(--font-medium);
  font-weight: 200;
  padding: var(--space-element) var(--space-inline);
  transition: background-color 0.2s ease, padding 0.2s ease;
}

.link-card:hover {
  background-color: var(--green-deep);
  padding-left: calc(var(--space-inline) + 4px);
  padding-right: calc(var(--space-inline) - 4px);
}

.link-card--sponsor {
  justify-content: space-between;
}

.link-card__logo {
  height: calc(var(--font-medium) * 1.6);
  width: auto;
  flex-shrink: 0;
}

/* Topic colors */
.topic-01 {
  background-color: var(--color-01-lite);
  color: var(--color-01-dark);
}

.topic-02 {
  background-color: var(--color-02-lite);
  color: var(--color-02-dark);
}

.topic-03 {
  background-color: var(--color-03-lite);
  color: var(--color-03-dark);
}

.topic-green {
  background-color: var(--green-lite);
  color: var(--green-dark);
}

/* ========================================
   6. COMPONENTS — Project card
   ======================================== */

.project-card {
  display: grid;
  grid-template-columns: 1fr;
  grid-template-rows: auto minmax(7em, auto) auto 1fr;
  text-decoration: none;
  transition: filter 0.2s ease;
}

.project-card:hover {
  filter: brightness(0.95);
}

.project-card__number {
  grid-row: 1;
  font-size: var(--font-large);
  font-weight: 200;
  transition: transform 0.2s ease;
}

.project-card__title {
  grid-row: 2;
  font-size: var(--font-large);
  line-height: 1.25;
  transition: transform 0.2s ease;
  hyphens: auto;
  overflow-wrap: break-word;
  align-self: start;
}

.project-card__description {
  grid-row: 3;
  font-size: var(--font-xsmall);
  font-weight: 300;
  margin-top: 1rem;
  line-height: 130%;
  transition: transform 0.2s ease;
}

.project-card__arrow {
  grid-row: 4;
  align-self: end;
  padding-top: 1rem;
  font-size: var(--font-large);
  font-weight: 200;
  transition: transform 0.2s ease;
}

.project-card:hover .project-card__number,
.project-card:hover .project-card__title,
.project-card:hover .project-card__description,
.project-card:hover .project-card__arrow {
  transform: translateX(4px);
}

/* ========================================
   6. COMPONENTS — Title bar (project pages)
   ======================================== */

.title-bar {
  display: flex;
  gap: var(--space-gap);
}

.title-bar__back {
  background-color: var(--green-dark);
  color: var(--green-lite);
  text-decoration: none;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: var(--font-large);
  font-weight: 200;
  aspect-ratio: 1 / 1;
  flex-shrink: 0;
  transition: background-color 0.2s ease;
  align-self: stretch;
}

.title-bar__back span {
  display: inline-block;
  transition: transform 0.2s ease;
}

.title-bar__back:hover {
  background-color: var(--green-deep);
}

.title-bar__back:hover span {
  transform: translateX(-4px);
}

.title-bar__title {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-bar) var(--space-inline);
}

.title-bar__title h1 {
  font-size: var(--font-large);
  margin: 0;
  display: flex;
  width: 100%;
  justify-content: space-between;
}

.title-bar__number {
  font-weight: 200;
}

.title-bar__name {
  font-weight: 300;
}

/* ========================================
   6. COMPONENTS — Video card (project pages)
   ======================================== */

.video-card {
  padding: 0;
  position: relative;
  overflow: hidden;
  aspect-ratio: 16 / 9;
  background-color: var(--green-dark);
  backface-visibility: hidden;
  -webkit-backface-visibility: hidden;
}

.video-card > iframe {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  border: none;
  display: block;
  z-index: 1;
}

.video-card__overlay {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 1rem;
  cursor: pointer;
  transition: opacity 0.3s ease;
  z-index: 2;
}

.video-card__overlay.is-hidden {
  opacity: 0;
  pointer-events: none;
}

.video-card__overlay-content {
  border-radius: var(--radius-card);
  padding: var(--space-element);
  display: flex;
  flex-direction: column;
  gap: 1rem;
  max-width: 400px;
  transition: filter 0.2s ease, padding 0.2s ease;
}

.video-card__overlay-content:hover {
  filter: brightness(0.95);
  padding-left: 36px;
  padding-right: 28px;
}

.video-card__hint {
  font-size: var(--font-xsmall);
  font-weight: 300;
  margin: 0;
  line-height: 1.6;
}

.video-card__play-button {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.video-card__play-icon {
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background-color: var(--green-dark);
  color: var(--green-lite);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 20px;
}

.topic-01 .video-card__play-icon {
  background-color: var(--color-01-dark);
  color: var(--color-01-lite);
}

.topic-02 .video-card__play-icon {
  background-color: var(--color-02-dark);
  color: var(--color-02-lite);
}

.topic-03 .video-card__play-icon {
  background-color: var(--color-03-dark);
  color: var(--color-03-lite);
}

.video-card__play-text {
  font-size: var(--font-xsmall);
  font-weight: 500;
}

/* ========================================
   6. COMPONENTS — Sibling project links (project pages)
   ======================================== */

.sibling-projects {
  display: flex;
  gap: var(--space-gap);
  align-items: center;
}

.sibling-projects .project-card--inline {
  flex: 1;
  display: flex;
  align-items: center;
  gap: 0.5rem;
  padding: var(--space-element) var(--space-inline);
  grid-template-columns: unset;
  grid-template-rows: unset;
}

.sibling-projects .project-card--inline .project-card__number,
.sibling-projects .project-card--inline .project-card__title,
.sibling-projects .project-card--inline .project-card__arrow {
  font-size: var(--font-medium);
  grid-row: unset;
  align-self: center;
}

.sibling-projects .project-card--inline .project-card__title {
  flex: 1;
}

.sibling-projects .project-card--inline .project-card__arrow {
  padding-top: 0;
}

/* ========================================
   6. COMPONENTS — Team grid (team page)
   ======================================== */

.team-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--space-gap);
}

.team-member {
  display: flex;
  align-items: center;
  gap: var(--space-element);
  border-radius: var(--radius-card);
  background-color: var(--green-lite);
  color: var(--green-dark);
  padding: calc(var(--space-element)*0.5) var(--space-card);
}

.team-member__photo {
  width: 140px;
  height: 140px;
  flex-shrink: 0;
  object-fit: cover;
  border-radius: 50%;
  filter: grayscale(100%) sepia(50%) hue-rotate(110deg) saturate(100%) brightness(0.95);
}

.team-member__info {
  flex: 1;
}

.team-member__info h3 {
  font-weight: 300;
  margin: 0;
}

.team-member__info p {
  font-weight: 200;
  margin: 0;
}

/* ========================================
   7. HEADER / NAVIGATION
   ======================================== */

header {
  padding: 0;
}

nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: nowrap;
  padding: 24px var(--radius-card);
  color: var(--green-lite);
}

.nav__logo {
  font-size: var(--font-large);
  text-decoration: none;
  transition: opacity 0.2s ease;
  display: flex;
  align-items: center;
}

.nav__logo img {
  height: 0.8em;
  width: auto;
  display: block;
}

.nav__logo:hover {
  opacity: 0.7;
}

.nav__tagline {
  font-size: var(--font-small);
  font-weight: 300;
  background-color: transparent;
  color: var(--green-lite);
  line-height: 1.6;
}

/* ========================================
   8. FOOTER
   ======================================== */

.footer {
  padding: 0;
  color: var(--green-lite);
}

.footer__sponsors {
  display: flex;
  justify-content: space-between;
  align-items: center;
  background-color: var(--green-dark);
  color: var(--green-lite);
  border-radius: var(--radius-card);
  padding: var(--space-element) var(--space-inline);
}

.footer__sponsors p {
  color: var(--green-lite);
  font-size: var(--font-xsmall);
  font-weight: 200;
}

.footer__sponsors img {
  height: 40px;
  width: auto;
  flex-shrink: 0;
}

.footer__copyright {
  text-align: center;
  font-size: var(--font-xsmall);
  padding: 2rem 0;
  color: var(--green-lite);
}

.footer__credit-btn {
  display: inline-block;
  background-color: transparent;
  color: var(--green-lite);
  border: 1px solid var(--green-lite);
  padding: 2px 8px;
  border-radius: var(--radius-small);
  text-decoration: none;
  font-weight: 500;
  line-height: 1.5;
  transition: background-color 0.2s ease, padding 0.2s ease;
}

.footer__credit-btn:hover {
  background-color: var(--green-main);
  color: var(--green-lite);
  padding-left: 10px;
  padding-right: 6px;
}

.mobile-break {
  display: none;
}

/* ========================================
   9. RESPONSIVE — 1024px
   ======================================== */

@media (max-width: 1024px) {
  :root {
    --space-card: 40px;
    --space-element: 24px;
    --space-bar: 24px;
    --space-inline: 32px;
  }

  .team-member {
    padding: var(--space-element) var(--space-card);
    gap: 20px;
  }

  .team-member__photo {
    width: 96px;
    height: 96px;
  }
}

/* ========================================
   9. RESPONSIVE — 768px (mobile)
   ======================================== */

@media (max-width: 768px) {
  :root {
    --font-large: clamp(22px, 1.375rem + 1.25vw, 32px);
    --font-medium: clamp(18px, 1.125rem + 0.75vw, 26px);
    --space-card: 32px;
    --space-bar: 16px;
    --space-gap: 1px;
  }

  .container {
    padding: 0 8px;
  }

  .nav__logo {
    font-size: var(--font-large);
  }

  .nav__tagline {
    font-size: var(--font-small);
  }

  /* Grid: collapse to single column */
  .grid-container {
    grid-template-columns: 1fr;
  }

  /* Cards: uniform padding on mobile */
  .link-card {
    padding: var(--space-card);
    font-size: var(--font-small);
    transition: none;
  }

  .link-card:hover {
    background-color: var(--green-dark);
    padding: var(--space-card);
  }

  .link-card--sponsor:hover {
    padding: var(--space-card);
  }

  .footer__credit-btn {
    transition: none;
  }

  .footer__credit-btn:hover {
    background-color: transparent;
    color: var(--green-lite);
    padding: 2px 8px;
  }

  /* Project cards: horizontal layout */
  .project-card {
    display: grid;
    grid-template-columns: auto 1fr auto;
    grid-template-rows: auto auto;
    gap: 0 1rem;
  }

  .project-card__number {
    grid-column: 1;
    grid-row: 1;
    font-size: var(--font-large);
  }

  .project-card__title {
    grid-column: 2;
    grid-row: 1;
    align-self: center;
    font-size: var(--font-large);
  }

  .title-break {
    display: none;
  }

  .project-card__arrow {
    grid-column: 3;
    grid-row: 1;
    align-self: start;
    font-size: var(--font-large);
    padding-top: 0;
  }

  .project-card__description {
    grid-column: 1 / -1;
    grid-row: 2;
  }

  /* Disable hover effects on touch */
  .project-card:hover {
    filter: none;
  }

  .project-card:hover .project-card__number,
  .project-card:hover .project-card__title,
  .project-card:hover .project-card__description,
  .project-card:hover .project-card__arrow {
    transform: none;
  }

  /* Title bar */
  .title-bar {
    align-items: stretch;
  }

  .title-bar__back {
    transition: none;
  }

  .title-bar__back span {
    transition: none;
  }

  .title-bar__back:hover {
    background-color: var(--green-dark);
  }

  .title-bar__back:hover span {
    transform: none;
  }

  /* Video card: square aspect ratio */
  .video-card {
    aspect-ratio: 1 / 1;
  }

  .video-card__overlay-content {
    padding: 24px;
    max-width: 90%;
  }

  .video-card__overlay-content:hover {
    padding-left: 28px;
    padding-right: 20px;
  }

  .video-card__play-icon {
    width: 40px;
    height: 40px;
    font-size: 18px;
  }

  /* Team grid: single column */
  .team-grid {
    grid-template-columns: 1fr;
  }

  .team-member {
    padding: var(--space-element) var(--space-card);
    gap: 16px;
    border-radius: var(--radius-card);
  }

  .team-member__photo {
    width: 84px;
    height: 84px;
  }

  /* Sibling projects: stack */
  .sibling-projects {
    flex-direction: column;
  }

  .sibling-projects .project-card--inline {
    width: 100%;
    padding: var(--space-card);
  }

  .footer__sponsors {
    flex-direction: column;
    align-items: center;
    gap: var(--space-element);
  }

  .footer__sponsors p {
    text-align: center;
  }

  /* Responsive image art direction: adjust aspect ratios for tablet/large mobile */
  .card.card-image {
    aspect-ratio: 3 / 2;
  }

  /* Index page images — adjust vertical positioning */
  .card-image--index-1 img {
    object-position: center 55%; /* was 65% */
  }

  .card-image--index-2 img {
    object-position: center 45%; /* was 55% */
  }

  /* Project page images — adjust for medical scene compositions */
  .card-image.topic-01 img {
    object-position: center 25%; /* was 30% — Narkose */
  }

  .card-image.topic-02 img {
    object-position: center 30%; /* was 35% — Intensivstation */
  }

  /* Study page and topic-03 images keep center positioning */
  .card-image.topic-green img,
  .card-image.topic-03 img {
    object-position: center 40%;
  }
}

/* ========================================
   9. RESPONSIVE — 480px (small mobile)
   ======================================== */

@media (max-width: 480px) {
  :root {
    --space-card: 24px;
    --space-element: 20px;
    --space-bar: 12px;
    --space-inline: 24px;
    --radius-card: 12px;
    --font-large: clamp(20px, 1.25rem + 1vw, 24px);
    --font-xsmall: clamp(14px, 0.875rem + 0.2vw, 16px);
  }

  nav {
    padding: 24px var(--radius-card);
  }

  .link-card--sponsor {
    padding-top: var(--space-element);
    padding-bottom: var(--space-element);
  }

  .link-card--sponsor:hover {
    padding-top: var(--space-element);
    padding-bottom: var(--space-element);
  }

  .mobile-break {
    display: inline;
  }

  .team-member {
    padding: var(--space-element) var(--space-card);
    gap: 12px;
  }

  .team-member__photo {
    width: 72px;
    height: 72px;
  }

  .video-card__overlay-content {
    padding: 16px;
    max-width: 95%;
    border-radius: var(--radius-small);
    transition: none;
  }

  .video-card__overlay-content:hover {
    filter: none;
    padding: 16px;
  }

  .video-card__hint {
    font-size: var(--font-xsmall);
  }

  .video-card__play-icon {
    width: 32px;
    height: 32px;
    font-size: 16px;
  }

  .video-card__play-button {
    gap: 0.5rem;
  }

  .footer__sponsors {
    border-radius: var(--radius-card);
    padding: var(--space-element) var(--space-card);
  }

  .footer__sponsors img {
    height: 40px;
  }

  .link-card__logo {
    height: calc(var(--font-medium) * 1.6);
  }

  /* Responsive image art direction: aggressive aspect ratio changes for small mobile */

  /* Index page focal images: 1:1 square for strong vertical presence */
  .card-image--index-1,
  .card-image--index-2 {
    aspect-ratio: 1 / 1;
  }

  .card-image--index-1 img {
    object-position: center 50%; /* centered for square crop */
  }

  .card-image--index-2 img {
    object-position: center 40%; /* VR headset focus */
  }

  /* Project images: 1:1 square for medical scenes with upper focus */
  .card-image.topic-01,
  .card-image.topic-02 {
    aspect-ratio: 1 / 1;
  }

  .card-image.topic-01 img {
    object-position: center 20%; /* Aggressive upward for Narkose */
  }

  .card-image.topic-02 img {
    object-position: center 25%; /* ICU equipment focus */
  }

  /* Study and Kaiserschnitt images: 4:3 moderate crop */
  .card-image.topic-green,
  .card-image.topic-03 {
    aspect-ratio: 4 / 3;
  }

  .card-image.topic-green img {
    object-position: center 35%;
  }

  .card-image.topic-03 img {
    object-position: center center; /* Generative image, centered composition */
  }

  /* Reduce image credit padding for narrow screens */
  .image-credit {
    right: 16px; /* was 24px */
  }
}

/* ========================================
   10. ACCESSIBILITY
   ======================================== */

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
  }
}

@media (prefers-contrast: more) {
  .card {
    border: 2px solid currentColor;
  }
}