/* Informatik lernen - keine externen Schriften oder Bibliotheken nötig. */
:root {
  --paper: #f7f6f0;
  --ink: #203a38;
  --muted: #616c68;
  --teal: #276b59;
  --teal-dark: #184d3f;
  --sage: #e3ece5;
  --line: #d8ded5;
  --orange: #ad5834;
  --white: #fffefa;
  --serif: Georgia, 'Times New Roman', serif;
  --sans: -apple-system, BlinkMacSystemFont, 'Segoe UI', Helvetica, Arial, sans-serif;
  --ease: cubic-bezier(.2,.7,.2,1);
}
*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 28px; }
body { margin: 0; background: var(--paper); color: var(--ink); font-family: var(--sans); line-height: 1.55; -webkit-font-smoothing: antialiased; }
[hidden] { display: none !important; }
button, input { font: inherit; }
button, a { -webkit-tap-highlight-color: transparent; }
button { cursor: pointer; }
a { color: inherit; text-decoration: none; }
p, h1, h2, h3 { margin: 0; }
button, input, a { touch-action: manipulation; }
a:focus-visible, button:focus-visible, input:focus-visible { outline: 3px solid #ad5834; outline-offset: 5px; }
::selection { background: #d4e5ba; color: var(--ink); }
.wrap { width: min(1184px, calc(100% - 96px)); margin-inline: auto; }
.icon { width: 21px; height: 21px; flex-shrink: 0; }
.sr-only { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0,0,0,0); white-space: nowrap; }
.skip-link { position: fixed; top: 10px; left: 10px; z-index: 10; transform: translateY(-160%); padding: 12px 18px; background: var(--ink); color: white; border-radius: 4px; }
.skip-link:focus { transform: none; }
.site-header { display: flex; align-items: center; justify-content: space-between; min-height: 106px; gap: 24px; border-bottom: 1px solid var(--line); }
.brand { display: inline-flex; align-items: center; gap: 12px; font-size: 19px; font-weight: 700; letter-spacing: -.5px; line-height: 1.25; }
.brand-mark { display: grid; place-items: center; width: 44px; height: 44px; border-radius: 6px; background: var(--ink); color: var(--paper); font: italic 35px/.8 var(--serif); padding-bottom: 5px; }
.brand-subtitle { display: block; font-size: 11px; font-weight: 450; color: var(--muted); letter-spacing: .15px; margin-top: 4px; }
.site-header nav { display: flex; gap: 33px; font-size: 13px; font-weight: 600; }
.site-header nav a { padding-block: 12px; }
.site-header nav a:hover { color: var(--teal); text-decoration: underline; text-underline-offset: 6px; }
.site-header nav a span { margin-left: 9px; }
.hero { display: grid; grid-template-columns: 1.17fr 1fr; align-items: center; gap: 45px; padding-block: 68px 64px; }
.eyebrow { font-size: 10px; font-weight: 700; line-height: 1.5; letter-spacing: 1.7px; text-transform: uppercase; }
.hero-kicker { display: flex; align-items: center; gap: 8px; color: var(--teal); margin-bottom: 24px; }
.live-dot { width: 6px; height: 6px; background: var(--teal); border-radius: 50%; }
h1 { font: 400 clamp(42px, 5.1vw, 66px)/1.08 var(--serif); letter-spacing: -2.5px; }
h1 em { font-weight: 400; color: var(--teal); }
.hero-description { max-width: 415px; margin-top: 22px; color: var(--muted); font-size: 16px; line-height: 1.7; }
.button { min-height: 48px; display: inline-flex; gap: 24px; align-items: center; justify-content: center; padding: 13px 20px; border-radius: 5px; border: 1px solid transparent; font-size: 13px; font-weight: 600; transition: background .2s, transform .2s var(--ease); }
.primary { color: #fffefa; background: var(--teal); }
.primary:hover { background: var(--teal-dark); transform: translateY(-2px); }
.hero .button { margin-top: 28px; }
.hero-text-link { display: inline-flex; align-items: center; gap: 9px; font-size: 12px; font-weight: 600; margin-left: 17px; padding-block: 14px; }
.hero-text-link:hover { text-decoration: underline; text-underline-offset: 4px; }
.hero-art { height: 345px; position: relative; display: grid; place-items: center; background-image: radial-gradient(#ced5c9 .9px, transparent .9px); background-size: 18px 18px; }
.paper { position: absolute; width: 248px; height: 297px; border: 1px solid #c4cec0; border-radius: 3px 9px 9px 3px; }
.paper-back { background: #e6e9d2; transform: rotate(-12deg) translate(-35px, -1px); padding: 15px; color: #516846; font-size: 9px; letter-spacing: 2px; }
.paper-middle { background: #f0d8bb; transform: rotate(8deg) translate(25px,-9px); padding: 15px; color: #805b40; font-size: 9px; letter-spacing: 2px; }
.paper-front { display: flex; flex-direction: column; justify-content: space-between; transform: rotate(-3deg); padding: 24px 23px 21px 29px; background: var(--teal); color: #f4f5de; border-color: #235d4e; box-shadow: 12px 17px 30px #233d3418; }
.paper-front::before { content: ''; position: absolute; top: 0; bottom: 0; left: 9px; width: 1px; background: #ffffff20; }
.paper-heading { display: flex; justify-content: space-between; align-items: center; font-size: 9px; letter-spacing: 1.5px; line-height: 1.4; }
.paper-heading > span { font-size: 27px; font-weight: 300; }
.paper-main { font: 35px/1.15 var(--serif); letter-spacing: -.4px; }
.paper-main i { color: #e8d895; }
.paper-bottom { display: flex; align-items: end; justify-content: space-between; border-top: 1px solid #ffffff48; padding-top: 15px; font-size: 8px; line-height: 1.65; letter-spacing: 1px; }
.paper-icon { font: 33px/1 var(--serif); letter-spacing: 3px; }
.paper-lines { margin-top: 20px; height: 190px; background: repeating-linear-gradient(transparent 0 18px,#73866635 18px 19px); }
.orbit { position: absolute; width: 26px; height: 26px; border: 1px solid #adbca5; border-radius: 50%; }
.orbit-one { left: 16px; top: 29px; }
.orbit-two { right: 7px; bottom: 50px; width: 9px; height: 9px; background: #d3dfc6; border: 0; }
.art-caption { position: absolute; bottom: -19px; left: 50%; width: max-content; transform: translateX(-50%); font-size: 10px; color: var(--muted); letter-spacing: .1px; }
.art-caption > span { display: inline-block; width: 20px; border-top: 1px solid #839483; vertical-align: middle; margin-right: 7px; }
.collection-stats { display: grid; grid-template-columns: 1.05fr 1.05fr 1.05fr .8fr; padding-block: 26px; border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.collection-stats > p { display: flex; align-items: center; gap: 14px; padding-inline: 25px; border-right: 1px solid var(--line); }
.collection-stats > p:first-child { padding-left: 0; }
.collection-stats > p:last-child { border-right: 0; }
.collection-stats p > strong { font: 37px/1 var(--serif); letter-spacing: -1px; }
.collection-stats p > span { font-size: 11px; color: var(--muted); line-height: 1.45; }
.collection-stats .language-icon { font: 27px/1 var(--serif); color: var(--teal); }
.language-note strong { color: var(--ink); font-weight: 600; }
.resources-section { padding-block: 73px 76px; }
.section-heading { display: flex; justify-content: space-between; align-items: end; gap: 28px; margin-bottom: 30px; }
.section-kicker { color: var(--teal); margin-bottom: 9px; }
h2 { font: 400 clamp(28px,3vw,39px)/1.15 var(--serif); letter-spacing: -1px; }
.section-heading > p { color: var(--muted); font-size: 12px; line-height: 1.6; padding-bottom: 2px; }
.resource-grid { display: grid; grid-template-columns: repeat(3,minmax(0,1fr)); gap: 21px; }
.resource-card { border: 1px solid var(--line); border-radius: 7px; overflow: hidden; display: flex; flex-direction: column; background: var(--white); transition: box-shadow .25s var(--ease),transform .25s var(--ease); }
.resource-card:hover { transform: translateY(-4px); box-shadow: 0 10px 24px #263f3710; }
.resource-visual { height: 178px; padding: 18px 24px; position: relative; overflow: hidden; background: #ecebd6; }
.resource-step { font-size: 8px; font-weight: 600; letter-spacing: 1.6px; position: relative; z-index: 1; }
.book-number { font: 62px/.95 var(--serif); letter-spacing: -2px; margin-top: 13px; display: flex; align-items: baseline; gap: 12px; }
.book-number > span { font: 9px/1 var(--sans); font-weight: 500; letter-spacing: 2px; }
.book-rule { display: block; width: 35px; border-top: 1px solid currentColor; opacity: .45; margin-block: 13px 10px; }
.book-caption { display: block; font-size: 7px; line-height: 1.35; font-weight: 600; letter-spacing: 1px; }
.cover-mark { position: absolute; right: -4px; bottom: -14px; font: italic 204px/.9 var(--serif); opacity: .065; transform: rotate(-12deg); }
.compact .resource-visual { background: #deebe4; color: #285e4d; }
.full .resource-visual { background: #244842; color: #f4f3df; }
.full .cover-mark { opacity: .09; }
.resource-content { display: flex; flex-direction: column; flex-grow: 1; padding: 24px; }
.resource-content .eyebrow { font-size: 9px; letter-spacing: 1px; color: var(--muted); margin-bottom: 6px; }
.resource-content h3 { font: 400 25px/1.25 var(--serif); letter-spacing: -.55px; }
.resource-description { font-size: 12px; line-height: 1.7; color: var(--muted); margin-top: 12px; margin-bottom: 20px; }
.file-meta { font-size: 10px; color: var(--muted); margin-top: auto; }
.file-meta > span { padding-inline: 5px; }
.resource-download { display: flex; justify-content: space-between; align-items: center; gap: 12px; font-size: 12px; font-weight: 650; border-top: 1px solid var(--line); margin-top: 17px; padding-top: 16px; min-height: 44px; }
.resource-download:hover { color: var(--teal); }
.resource-download .icon { width: 18px; height: 18px; }
.exams-section { background: #eeefe8; border-block: 1px solid var(--line); padding-block: 67px 55px; }
.catalog-controls { display: flex; justify-content: space-between; align-items: center; flex-wrap: wrap; gap: 16px; margin-top: 34px; }
.subject-filters { display: inline-flex; align-items: center; gap: 4px; padding: 4px; background: #e1e6dc; border-radius: 6px; }
.filter-button { border: none; background: transparent; color: var(--ink); border-radius: 4px; padding: 10px 14px; font-size: 11px; font-weight: 600; min-height: 40px; transition: background .18s, box-shadow .18s; }
.filter-button span { padding-left: 7px; opacity: .65; font-size: 10px; }
.filter-button[aria-pressed="true"] { background: var(--white); box-shadow: 0 1px 4px #203a3815; }
.filter-button:hover { background: #f8f8f1; }
.search-field { position: relative; flex-basis: 320px; }
.search-field > .icon { position: absolute; top: 13px; left: 13px; width: 17px; height: 17px; color: var(--muted); pointer-events: none; }
.search-field input { width: 100%; min-height: 45px; padding: 11px 12px 11px 41px; border: 1px solid #cbd4c7; background: #fffefa; border-radius: 5px; color: var(--ink); font-size: 11px; }
.search-field input::placeholder { color: #657068; opacity: 1; }
.catalog-caption { display: flex; justify-content: space-between; gap: 15px; font-size: 10px; color: var(--muted); margin-block: 20px 12px; }
.catalog-caption > span > span { padding-left: 6px; }
.exam-grid { display: grid; grid-template-columns: repeat(2,minmax(0,1fr)); gap: 18px; }
.exam-card { border: 1px solid #d6ddcf; border-radius: 6px; padding: 22px; background: var(--white); }
.exam-topline { display: flex; justify-content: space-between; align-items: center; gap: 10px; margin-bottom: 15px; }
.exam-number { font-size: 9px; font-weight: 650; letter-spacing: 1.1px; white-space: nowrap; color: var(--muted); }
.subject-label { font-size: 9px; line-height: 1.4; display: inline-flex; align-items: center; gap: 6px; color: var(--teal-dark); background: #e7f0e8; padding: 4px 7px; border-radius: 3px; }
.subject-label.algorithms { background: #f7ece1; color: #96502d; }
.subject-dot { background: currentColor; width: 4px; height: 4px; border-radius: 50%; flex-shrink: 0; }
.exam-card h3 { font: 400 27px/1.2 var(--serif); letter-spacing: -.5px; }
.exam-description { font-size: 11px; color: var(--muted); margin-top: 6px; }
.download-pair { display: grid; grid-template-columns: repeat(2,minmax(0,1fr)); gap: 10px; margin-top: 20px; }
.pdf-download { display: flex; justify-content: space-between; align-items: center; gap: 8px; border: 1px solid #d8dfd3; border-radius: 4px; min-height: 64px; padding: 10px 12px; transition: border-color .18s, background .18s; }
.pdf-download strong { font-size: 12px; font-weight: 600; display: block; }
.pdf-download small { display: block; font-size: 9px; color: var(--muted); margin-top: 2px; }
.pdf-download small span { margin-inline: 3px; }
.pdf-download .icon { height: 18px; width: 18px; color: var(--teal); }
.pdf-download.solution { background: #edf3ed; border-color: #dce5da; }
.pdf-download:hover { border-color: var(--teal); background: #e0eadd; }
.study-note { display: flex; align-items: flex-start; gap: 18px; margin-top: 32px; border-left: 2px solid #8b9f83; padding: 6px 0 6px 23px; }
.note-marker { font-size: 24px; color: var(--teal); line-height: 1; }
.study-note h3 { font-size: 12px; font-weight: 650; margin-bottom: 3px; }
.study-note p { font-size: 11px; color: var(--muted); }
.empty-state { padding: 50px 20px; background: var(--white); border: 1px dashed #b6c3ad; text-align: center; border-radius: 6px; }
.empty-icon { font: italic 45px var(--serif); color: var(--teal); }
.empty-state h3 { font: 27px var(--serif); margin: 12px 0; }
.empty-state p { font-size: 13px; color: var(--muted); margin-bottom: 23px; }
.site-footer { display: flex; justify-content: space-between; align-items: center; gap: 24px; padding-block: 34px; }
.footer-brand { font-size: 16px; }
.footer-brand .brand-mark { width: 36px; height: 36px; font-size: 29px; }
.footer-brand .brand-subtitle { font-size: 10px; }
.site-footer > p { font-size: 10px; line-height: 1.8; }
.site-footer > p > span { color: var(--muted); }
.back-to-top { display: flex; align-items: center; gap: 12px; padding-block: 10px; font-size: 11px; }
.back-to-top .icon { width: 16px; height: 16px; }
.back-to-top:hover { color: var(--teal); text-decoration: underline; text-underline-offset: 5px; }
@media (prefers-reduced-motion: no-preference) {
  .hero-copy { animation: appear .65s var(--ease) both; }
  .hero-art { animation: appear .85s .08s var(--ease) both; }
  @keyframes appear { from { opacity: 0; transform: translateY(12px); } to { opacity: 1; transform: translateY(0); } }
}
@media (max-width: 1100px) {
  .wrap { width: calc(100% - 64px); }
  .hero { gap: 25px; }
  .hero-text-link { margin-left: 0; display: flex; width: fit-content; }
  .collection-stats > p { gap: 10px; padding-inline: 18px; }
  .resource-content { padding: 21px; }
  .exam-topline { flex-wrap: wrap; }
}
@media (max-width: 780px) {
  .wrap { width: calc(100% - 40px); }
  .site-header { min-height: 88px; }
  .site-header nav { gap: 20px; font-size: 11px; }
  .hero { grid-template-columns: 1.2fr .8fr; padding-block: 48px; gap: 18px; }
  h1 { font-size: 45px; letter-spacing: -1.8px; }
  .hero-kicker { font-size: 8px; letter-spacing: 1px; }
  .hero-description { font-size: 14px; }
  .hero-art { height: 270px; }
  .paper { width: 175px; height: 225px; }
  .paper-front { padding: 20px 17px; }
  .paper-main { font-size: 27px; }
  .paper-heading { font-size: 7px; }
  .paper-heading > span { font-size: 22px; }
  .paper-bottom { font-size: 6px; padding-top: 10px; }
  .paper-icon { font-size: 25px; }
  .art-caption { display: none; }
  .collection-stats { grid-template-columns: repeat(3,minmax(0,1fr)); }
  .collection-stats p > strong { font-size: 32px; }
  .collection-stats p > span { font-size: 10px; }
  .collection-stats > p:nth-child(3) { border-right: 0; padding-right: 0; }
  .collection-stats .language-note { display: none; }
  .resources-section { padding-block: 52px; }
  .section-heading { align-items: start; flex-direction: column; gap: 13px; }
  .section-heading > p br { display: none; }
  .resource-grid { gap: 13px; }
  .resource-content { padding: 17px; }
  .resource-content h3 { font-size: 22px; }
  .resource-content .eyebrow { font-size: 8px; letter-spacing: .5px; }
  .resource-description { font-size: 11px; }
  .resource-download { font-size: 10px; gap: 4px; }
  .resource-visual { height: 160px; padding: 16px 18px; }
  .book-number { font-size: 55px; gap: 8px; }
  .book-number > span { font-size: 7px; letter-spacing: 1px; }
  .file-meta { font-size: 9px; }
  .file-meta > span { padding-inline: 2px; }
  .exams-section { padding-block: 48px; }
  .exam-card { padding: 18px; }
  .exam-card h3 { font-size: 24px; }
  .download-pair { gap: 7px; }
  .pdf-download { padding: 9px; gap: 4px; }
  .pdf-download .icon { width: 14px; }
  .pdf-download strong { font-size: 11px; }
  .pdf-download small { font-size: 8px; }
  .search-field { flex-basis: 280px; }
}
@media (max-width: 600px) {
  .site-header { min-height: 79px; gap: 12px; }
  .brand { font-size: 17px; gap: 9px; }
  .brand-mark { width: 37px; height: 39px; font-size: 31px; }
  .brand-subtitle { font-size: 9px; }
  .site-header nav { gap: 14px; font-size: 11px; }
  .site-header nav a:first-child { display: none; }
  .hero { display: block; padding-block: 42px 32px; }
  h1 { font-size: clamp(42px,11vw,58px); }
  .hero-kicker { font-size: 8px; letter-spacing: 1.1px; margin-bottom: 17px; }
  .hero-description { max-width: 380px; margin-top: 17px; font-size: 15px; }
  .hero .button { margin-top: 23px; }
  .hero-text-link { margin-top: 2px; font-size: 12px; }
  .hero-art { display: none; }
  .collection-stats { padding-block: 21px; }
  .collection-stats > p { flex-direction: column; align-items: start; gap: 5px; padding-inline: 15px; }
  .collection-stats p > strong { font-size: 35px; }
  .collection-stats p > span { max-width: 95px; font-size: 10px; }
  .resources-section { padding-block: 39px 43px; }
  h2 { font-size: 31px; }
  .section-kicker { font-size: 9px; letter-spacing: 1.25px; }
  .section-heading { margin-bottom: 24px; }
  .resource-grid { grid-template-columns: 1fr; gap: 16px; }
  .resource-card { flex-direction: row; }
  .resource-visual { width: 94px; height: auto; flex-shrink: 0; padding: 20px 13px; }
  .resource-step { font-size: 6px; letter-spacing: .5px; }
  .book-number { flex-direction: column; align-items: start; font-size: 49px; gap: 8px; margin-top: 23px; }
  .book-number > span { font-size: 7px; }
  .book-rule { width: 24px; margin-top: 18px; }
  .book-caption { font-size: 5px; letter-spacing: .3px; }
  .cover-mark { font-size: 130px; right: -15px; }
  .resource-content { padding: 20px 17px 17px; min-width: 0; }
  .resource-content h3 { font-size: 24px; }
  .resource-content .eyebrow { font-size: 8px; }
  .resource-description { font-size: 12px; margin-top: 9px; margin-bottom: 14px; }
  .resource-download { font-size: 11px; margin-top: 12px; padding-top: 10px; }
  .file-meta { font-size: 9px; }
  .catalog-controls { margin-top: 26px; gap: 13px; }
  .subject-filters { width: 100%; }
  .filter-button { flex: 1; padding-inline: 7px; min-height: 44px; font-size: 12px; }
  .search-field { flex-basis: 100%; }
  .search-field input { font-size: 16px; padding-right: 8px; }
  .search-field input::placeholder { font-size: 12px; }
  .exam-grid { grid-template-columns: 1fr; gap: 14px; }
  .exam-card { padding: 21px; }
  .exam-topline { gap: 10px; }
  .exam-card h3 { font-size: 28px; }
  .exam-description { font-size: 11px; }
  .download-pair { gap: 10px; }
  .pdf-download { padding: 11px 12px; }
  .pdf-download strong { font-size: 12px; }
  .pdf-download small { font-size: 9px; }
  .pdf-download .icon { width: 18px; }
  .study-note { padding-left: 15px; gap: 12px; }
  .study-note p { font-size: 12px; }
  .site-footer { flex-wrap: wrap; padding-block: 28px; gap: 22px; }
  .site-footer > p { order: 3; flex-basis: 100%; border-top: 1px solid var(--line); padding-top: 17px; }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation: none !important; transition: none !important; }
}