.skip-link { position: fixed; inset: 8px auto auto 8px; z-index: 20; transform: translateY(-160%); background: var(--md-primary); color: var(--md-on-primary); }
.skip-link:focus { transform: translateY(0); }
#main-content, #topics, .lesson-figures { scroll-margin-block-start: 75px; }
.lesson-context { border-block-start: 1px solid var(--md-outline-variant); margin-block-start: 1.1rem; padding-block-start: 1rem; }
.lesson-context :is(h3, h4) { font-size: 1rem; font-weight: 650; margin-block-end: .4rem; }
.lesson-foundation p, .lesson-context p, .lesson-fact li { max-width: 68ch; line-height: 1.65; }
.lesson-foundation p + p { margin-block-start: .8rem; }
.lesson-figures { margin-block-start: 1.75rem; }
.lesson-notes > .lesson-figures { margin-block-start: 0; }
.lesson-figures h2 { font-size: 1.375rem; margin-block-end: .75rem; }
.lesson-figure-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(min(100%, 285px), 1fr)); gap: 1rem; }
.lesson-figure-grid figure { margin: 0; min-width: 0; }
.lesson-figure-grid img { display: block; max-width: 100%; height: auto; object-fit: contain; border-radius: 10px; }
.lesson-diagram { width: 100%; background: var(--md-surface-lowest); }
.lesson-photo { width: auto; max-height: 420px; }
.lesson-figure-grid figcaption { max-width: 65ch; padding-block: .7rem; font-size: .94rem; line-height: 1.5; }
.scene-grip {
  position: absolute; width: 44px; height: 44px; transform: translate(-50%, -50%);
  display: grid; place-items: center; cursor: grab; touch-action: none;
  user-select: none; -webkit-tap-highlight-color: transparent;
}
.scene-grip::before {
  content: ""; width: 17px; height: 17px; border: 2px solid var(--tone-ink); background: var(--md-surface-lowest);
  border-radius: 50%; box-shadow: 0 0 0 2px var(--md-surface-lowest);
}
.scene-grip:active { cursor: grabbing; }
.scene-grip:active::before { background: var(--tone-ink); }
.scene-grip[hidden] { display: none; }
.scene-switch.practice-button {
  position: absolute; left: 32.8%; top: 28%; transform: translate(-50%, -50%);
  width: max(44px, 21%); height: max(44px, 17%); padding: 0; border: 1px dashed var(--tone-ink);
  border-radius: 9px; background: transparent; color: transparent; font-size: 0; box-shadow: none;
}
.scene-switch.practice-button:hover, .scene-switch.practice-button:focus-visible { background: var(--md-state-hover); }
.scene-hint { padding-block-start: .45rem; color: var(--md-on-surface-variant); font-size: .84rem; }
.scene-states { display: flex; flex-wrap: wrap; gap: .4rem; margin-block-end: .65rem; }
.scene-states [aria-pressed="true"] { background: var(--md-secondary-container); color: var(--md-on-secondary-container); }
.model-play.practice-button { background: var(--md-primary); color: var(--md-on-primary); }
.model-play.practice-button:not(:disabled):is(:hover,:focus-visible) { background: var(--md-primary-hover); }
.model-play.practice-button:disabled { background: var(--md-surface-container-high); color: var(--md-on-surface-variant); }
.model-actions { margin-block: .65rem .85rem; }
.lesson-lab-link { margin-block: .8rem 0; }
.course-lesson-strip { margin-block: 1.65rem 0; }
.course-lesson-strip .section-heading { flex-wrap: wrap; gap: .65rem; }
.course-lesson-rail {
  display: grid; grid-auto-flow: column; grid-auto-columns: clamp(160px, 29%, 255px); gap: 12px;
  overflow-x: auto; overscroll-behavior-inline: contain; scroll-snap-type: x mandatory; padding: 3px 3px .8rem;
}
.course-lesson-tile {
  display: grid; grid-template-rows: auto auto 1fr; gap: .45rem; min-width: 0; padding: .65rem; scroll-snap-align: start;
  border: 1px solid var(--md-outline-variant); border-radius: 10px; background: var(--md-surface-container-low);
}
.course-lesson-tile:is(:hover,:focus-visible) { border-color: var(--md-primary); }
.course-lesson-tile canvas { border-radius: 6px; }
.course-lesson-tile span { color: var(--md-on-surface-variant); font-size: .81rem; }
.course-lesson-tile strong { font-size: .98rem; line-height: 1.35; }
.course-tabs + .labs-page, .course-tabs + .lab-page { margin-block-start: .8rem; }
@media (max-width: 600px) {
  .course-lesson-rail { grid-auto-columns: minmax(150px, 64%); }
}
@media (max-width: 380px) {
  .course-tab { justify-content: center; flex: 1 0 auto; padding-inline: 6px; }
  .course-tab .m3-icon { display: none; }
}

/* Public landing and course navigation */
html { scroll-padding-top: 28px; }
.practice-topbar { position: static; border: 0; background: var(--paper); }
.practice-topbar-inner, .practice-page, .site-footer-inner {
  width: min(100%, 1440px);
  margin-inline: auto;
  padding-inline: clamp(20px, 6.111vw, 88px);
}
.practice-topbar-inner { min-height: 70px; padding-top: 22px; }
.practice-page { max-width: none; padding-block: 31px 72px; }
.site-context, .site-courses, .site-exams, .site-utilities { display: flex; align-items: center; }
.site-courses, .site-exams {
  min-height: 48px;
  gap: 5px;
  color: var(--muted);
  font-size: .875rem;
  font-weight: 600;
  white-space: nowrap;
}
.site-courses:hover, .site-exams:hover { color: var(--ink); }
.site-context, .site-utilities { gap: clamp(14px, 2.2vw, 32px); }
.site-exams .m3-icon, .site-courses .m3-icon { font-size: 17px; }
.practice-profile-link {
  min-width: 148px;
  width: auto;
  padding-inline: 14px;
  border-radius: 17px;
  background: var(--md-surface-container-low);
  box-shadow: var(--md-elevation-1);
  font-weight: 650;
  white-space: nowrap;
}
.practice-profile-link .m3-icon { width: 20px; height: 20px; }
.practice-profile-link span { position: static; width: auto; height: auto; clip: auto; overflow: visible; }
.practice-page .practice-button { border-radius: 14px; }
.practice-page .practice-button:is(.primary,.secondary,.tonal):not(:disabled) { box-shadow: var(--md-elevation-1); }

.home-page { --hero-inset: 96px; padding-block-start: 26px; }
.catalogue-hero {
  display: grid;
  justify-items: center;
  align-content: center;
  min-block-size: calc(100svh - var(--hero-inset));
  padding-block-end: clamp(18px, 4svh, 44px);
  text-align: center;
}
.catalogue-hero h1 {
  font-size: clamp(42px, 5.278vw, 76px);
  font-weight: 700;
  line-height: 1.05;
  letter-spacing: -.035em;
}
.catalogue-hero > p { margin-block-start: 13px; color: var(--muted); font-size: 19px; line-height: 26px; font-weight: 500; }
.catalogue-poster {
  width: min(100%, 936px);
  height: auto;
  aspect-ratio: 936 / 486;
  object-fit: cover;
  margin-block-start: 31px;
  border-radius: 32px;
  background: #151f34;
  box-shadow: var(--md-elevation-2);
}
.catalogue-scroll {
  display: grid;
  justify-items: center;
  gap: 7px;
  margin-block-start: 21px;
  padding: 0 12px;
  border-radius: 14px;
  color: var(--muted);
  font-size: 15px;
  line-height: 22px;
  font-weight: 600;
}
.catalogue-scroll-icon {
  display: grid;
  place-items: center;
  width: 52px;
  height: 52px;
  border-radius: 50%;
  color: var(--md-primary);
  background: var(--md-surface-container);
  box-shadow: var(--md-elevation-1);
}
.catalogue-scroll:hover .catalogue-scroll-icon { background: var(--md-surface-container-high); }
.catalogue-courses, .catalogue-carousel { width: min(100%, 1072px); margin-inline: auto; }
.catalogue-courses { margin-block-start: clamp(36px, 6svh, 68px); }
.catalogue-courses > h2 { font-size: 48px; letter-spacing: -.028em; line-height: 1.2; margin-block-end: 52px; }
.catalogue-courses > h2:focus { outline: none; }
.course-catalogue-grid {
  display: grid;
  aspect-ratio: 1072 / 519;
  grid-template-columns: minmax(0, 600fr) minmax(0, 448fr);
  grid-template-rows: repeat(3, minmax(0, 1fr));
  gap: 24px;
}
.course-bento-item { position: relative; min-width: 0; display: block; grid-column: auto; padding: 0; border: 0; border-radius: 32px; box-shadow: none; }
.bento-fizyka { grid-row: span 2; }
.bento-face {
  position: absolute;
  inset: 0;
  overflow: hidden;
  border-radius: inherit;
  background: #f4dab1;
  color: #1a2230;
  box-shadow: var(--md-elevation-2);
  transition: transform 170ms cubic-bezier(.2,.75,.25,1), box-shadow 170ms ease-out;
  pointer-events: none;
}
.bento-face img { position: absolute; inset: 0 0 0 auto; width: 63%; height: 100%; object-fit: cover; }
.bento-face::after { content: ''; position: absolute; inset: 0; background: linear-gradient(90deg, #f4dab1 48%, transparent 66%); }
.bento-mat-6 .bento-face { background: #ee662e; }
.bento-mat-6 .bento-face::after { background: linear-gradient(90deg, #ee662e 48%, transparent 66%); }
.bento-alg-9 .bento-face { color: #f2efff; background: #252849; }
.bento-alg-9 .bento-face::after { background: linear-gradient(90deg, #252849 40%, transparent 60%); }
.bento-geo-9 .bento-face { color: #1d3e31; background: #bfdfcc; }
.bento-geo-9 .bento-face::after { background: linear-gradient(90deg, #bfdfcc 41%, transparent 63%); }
.bento-fizyka .bento-face { color: var(--ink); background: #151f34; }
.bento-fizyka img { width: 100%; }
.bento-fizyka .bento-face::after {
  background: linear-gradient(180deg, transparent 42%, rgb(13 17 25 / .35) 66%, rgb(13 17 25 / .88));
  border-radius: inherit;
  box-shadow: inset 0 0 0 1px var(--md-outline);
}
.bento-label { position: absolute; z-index: 1; left: 22px; top: 50%; transform: translateY(-50%); }
.bento-fizyka .bento-label { top: auto; bottom: 16px; transform: none; }
.bento-label h3 { font-size: clamp(21px, 2vw, 27px); letter-spacing: -.022em; line-height: 1.18; }
.bento-fizyka h3 { font-size: clamp(28px, 3vw, 40px); }
.bento-label span { display: block; margin-top: 5px; font-size: 15px; font-weight: 500; }
@media (hover: hover) and (pointer: fine) {
  .course-bento-item:hover { position: relative; z-index: 1; box-shadow: none; }
  .course-bento-item:hover .bento-face {
    transform: translateY(-3px) scale(1.025);
    box-shadow: 0 19px 36px rgb(0 0 0 / .72);
  }
}
@media (prefers-reduced-motion: reduce) {
  .course-bento-item:hover .bento-face { transform: none; }
}

.catalogue-carousel {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  grid-template-areas: 'heading controls' 'slides slides' 'markers markers';
  align-items: center;
  gap: 20px 14px;
  margin-block-start: 72px;
}
.catalogue-carousel > h2 { grid-area: heading; font-size: clamp(30px, 3.2vw, 40px); line-height: 1.16; letter-spacing: -.024em; }
.catalogue-slides { grid-area: slides; display: grid; }
.catalogue-slide {
  grid-area: 1 / 1;
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(220px, 390px);
  grid-template-areas: 'copy art';
  min-width: 0;
  align-items: stretch;
  gap: 22px;
  padding: 14px 14px 14px 36px;
  border-radius: 32px;
  background: var(--md-surface-container);
  box-shadow: var(--md-elevation-2);
  visibility: hidden;
  opacity: 0;
  transition: opacity 240ms ease-out, visibility 0s 240ms;
}
.catalogue-slide[data-active="true"] { visibility: visible; opacity: 1; transition-delay: 0s; }
.catalogue-slide-copy { grid-area: copy; align-self: center; padding-block: 10px; }
.catalogue-slide h3 { max-width: 20ch; font-size: clamp(26px, 3.1vw, 39px); line-height: 1.08; letter-spacing: -.02em; }
.catalogue-slide p { margin-block: 5px 24px; color: var(--muted); font-weight: 550; }
.catalogue-slide-art { grid-area: art; width: 100%; height: 218px; object-fit: cover; border-radius: 23px; }
.carousel-controls { grid-area: controls; display: flex; gap: 8px; }
.carousel-controls .carousel-control {
  width: 48px;
  min-width: 48px;
  height: 48px;
  padding: 0;
  border-color: var(--line);
  border-radius: 15px;
  background: var(--md-surface-container);
  color: var(--ink);
  box-shadow: var(--md-elevation-1);
}
.carousel-control .m3-icon { font-size: 21px; }
.carousel-control:not(:disabled):hover { background: var(--md-surface-container-high); }
.carousel-markers { grid-area: markers; display: flex; gap: 6px; }
.carousel-markers span { width: 20px; height: 4px; background: #4b5566; border-radius: 2px; }
.carousel-markers .current { background: var(--md-primary); }

.course-heading { display: flex; align-items: center; justify-content: space-between; gap: 14px; margin-block: 4px 29px; }
.course-heading-title { display: flex; flex-wrap: wrap; align-items: baseline; column-gap: 15px; }
.course-heading h1 { font-size: clamp(42px, 4.31vw, 62px); font-weight: 700; line-height: 1.04; letter-spacing: -.032em; }
.course-heading-title > span { color: var(--muted); font-weight: 600; font-size: 19px; white-space: nowrap; }
.course-tabs { gap: 4px; margin-bottom: 16px; border: 0; overflow: visible; flex-wrap: wrap; }
.course-heading .course-tabs { margin: 0; }
.course-tab { min-height: 48px; border: 0; padding-inline: 16px; border-radius: 14px; font-size: 15px; font-weight: 600; }
.course-tab[aria-current="page"] { background: var(--md-primary-container); color: var(--md-primary); }
.course-banner {
  --banner-inset: 16px;
  --banner-radius: 32px;
  display: grid;
  grid-template-columns: minmax(0, .96fr) minmax(0, 1.04fr);
  align-items: center;
  gap: clamp(16px, 3vw, 40px);
  padding: var(--banner-inset);
  min-height: clamp(310px, 27vw, 384px);
  border-radius: var(--banner-radius);
  background: linear-gradient(118deg, var(--md-surface-container-low), color-mix(in srgb, var(--tone-deep) 74%, var(--md-surface)));
  box-shadow: var(--md-elevation-2);
}
.course-banner-media {
  width: min(100%, 720px);
  justify-self: end;
  overflow: hidden;
  border-radius: calc(var(--banner-radius) - var(--banner-inset));
}
.course-banner-copy { min-width: 0; padding: clamp(8px, 1.8vw, 22px); }
.course-banner-copy h2 { font-size: clamp(30px, 3.45vw, 49px); line-height: 1.12; letter-spacing: -.025em; text-wrap: balance; max-width: 20ch; }
.course-banner-copy .practice-button { margin-top: 24px; }
.lesson-section-number { margin-bottom: 14px; color: var(--md-primary); font-size: 17px; font-weight: 650; }
.course-lesson-strip { margin-top: 30px; }
.course-strip-heading {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 4px 14px;
  margin-bottom: 12px;
}
.course-position { color: var(--muted); font-size: .875rem; font-weight: 600; }
.course-strip-heading h2 { font-size: clamp(23px, 2.5vw, 29px); line-height: 1.25; }
.course-lesson-rail {
  grid-template-columns: repeat(3, minmax(0,1fr));
  grid-auto-flow: row;
  grid-auto-columns: auto;
  overflow: visible;
  padding: 0;
  gap: 16px;
}
.course-lesson-tile.practice-button {
  min-width: 0;
  display: grid;
  grid-template: auto / minmax(56px, 106px) minmax(0, 1fr);
  align-items: center;
  gap: 13px;
  min-height: 112px;
  padding: 12px;
  border-radius: 20px;
  background: var(--md-surface-container);
  text-align: left;
  color: var(--ink);
  box-shadow: var(--md-elevation-1);
  letter-spacing: 0;
}
.course-lesson-tile[aria-pressed="true"] { border-color: var(--md-primary); }
.course-lesson-tile img { display: block; width: 100%; height: auto; }
@media (hover: hover) and (pointer: fine) and (prefers-reduced-motion: no-preference) {
  .course-lesson-tile.practice-button:hover { transform: translateY(-3px) scale(1.025); }
}
.lesson-tile-copy { min-width: 0; display: grid; gap: 4px; }
.lesson-tile-copy small { font-size: .8125rem; color: var(--muted); }
.lesson-tile-copy strong { color: var(--ink); overflow-wrap: anywhere; }
.course-topics { margin-top: 46px; }

@media (max-width: 760px) {
  .practice-topbar-inner, .practice-page, .site-footer-inner { padding-inline: 20px; }
  .catalogue-carousel { margin-top: 60px; }
  .catalogue-slide { grid-template-columns: minmax(0, 1fr) minmax(0, 45%); padding-left: 22px; gap: 12px; }
  .catalogue-slide-art { height: 172px; align-self: center; }
  .course-heading { align-items: start; flex-direction: column; margin-bottom: 16px; }
  .course-lesson-rail { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
@media (min-width: 541px) and (max-height: 840px) {
  .catalogue-poster { width: min(100%, 936px, max(320px, calc((100svh - 375px) * 1.926))); }
}
@media (max-width: 540px) {
  .practice-topbar-inner { min-height: 66px; padding-top: 18px; }
  .site-courses { display: none; }
  .site-exams .m3-icon { display: none; }
  .site-utilities { gap: 10px; }
  .practice-profile-link { min-width: 0; gap: 6px; padding-inline: 10px; }
  .home-page { --hero-inset: 86px; padding-block-start: 20px; }
  .catalogue-hero h1 { font-size: clamp(37px, 12.3vw, 48px); line-height: 1.02; letter-spacing: -.029em; }
  .catalogue-hero h1 span { display: block; }
  .catalogue-hero > p { margin-block-start: 13px; font-size: clamp(13px, 3.85vw, 15px); line-height: 23px; }
  .catalogue-poster { margin-block-start: 25px; aspect-ratio: 350 / 330; max-height: max(156px, calc(100svh - 396px)); border-radius: 26px; }
  .catalogue-scroll { margin-block-start: 34px; }
  .catalogue-courses > h2 { font-size: 37px; margin-bottom: 34px; }
  .course-catalogue-grid { aspect-ratio: auto; grid-template-columns: minmax(0, 1fr); grid-template-rows: none; gap: 16px; }
  .course-bento-item { grid-row: auto; border-radius: 26px; }
  .course-bento-item::before { display: block; padding-top: 40%; content: ''; }
  .bento-fizyka::before { padding-top: 58.286%; }
  .bento-label h3 { font-size: 23px; }
  .bento-fizyka h3 { font-size: 32px; }
  .catalogue-carousel { grid-template-areas: 'heading heading' 'slides slides' 'markers controls'; margin-block-start: 58px; gap: 18px 10px; }
  .catalogue-slide {
    grid-template: auto 1fr / minmax(0, 1fr);
    grid-template-areas: 'art' 'copy';
    padding: 12px;
    border-radius: 26px;
    gap: 12px;
  }
  .catalogue-slide-art { height: auto; aspect-ratio: 326 / 150; border-radius: 18px; }
  .catalogue-slide-copy { align-self: stretch; display: flex; flex-direction: column; align-items: start; padding: 0 8px 6px; }
  .catalogue-slide h3 { font-size: 27px; }
  .catalogue-slide p { margin-bottom: 18px; }
  .catalogue-slide .practice-button { margin-top: auto; }
  .course-heading-title { column-gap: 8px; }
  .course-heading h1 { font-size: clamp(34px, 10.4vw, 43px); }
  .course-heading-title > span { font-size: 16px; }
  .course-tab { flex: 0 0 auto; padding-inline: 13px; font-size: 14px; }
  .course-banner { --banner-inset: 12px; --banner-radius: 26px; grid-template-columns: minmax(0, 1fr); min-height: 0; }
  .course-banner-copy { padding: 9px 8px 0; }
  .course-banner-copy h2 { font-size: 28px; max-width: 22ch; }
  .course-banner-copy .practice-button { margin-top: 13px; }
  .lesson-section-number { font-size: 15px; margin-bottom: 6px; }
  .course-lesson-strip { margin-top: 24px; }
  .course-lesson-rail { grid-template-columns: minmax(0, 1fr); }
  .course-lesson-tile.practice-button { min-height: 87px; }
}
@media (max-width: 380px) {
  .practice-profile-link .m3-icon { display: none; }
}
@media (max-width: 355px) {
  .practice-topbar-inner, .practice-page, .site-footer-inner { padding-inline: 15px; }
  .site-utilities { gap: 9px; }
  .practice-profile-link { padding-inline: 9px; font-size: .8125rem; }
  .course-tab { padding-inline: 10px; }
}

.course-section-picker { display: flex; flex-wrap: wrap; align-items: center; gap: 8px 14px; margin-block: 0 20px; font-weight: 650; }
.course-section-picker select {
  min-width: 0; max-width: 100%; min-height: 44px; padding: 8px 28px 8px 12px;
  border: 1px solid var(--md-outline); border-radius: 10px; color: var(--ink); background: var(--md-surface-container);
}
.course-section-picker select:focus-visible { outline: 3px solid var(--md-primary); outline-offset: 3px; }
.course-formula-plate {
  display: grid; place-items: center; min-height: 140px; aspect-ratio: 16 / 9;
  background: var(--tone); color: var(--tone-ink); font-size: clamp(18px, 3vw, 38px); padding: 12px;
}
.course-formula-plate .formula-ink { background: transparent; margin: 0; padding: 8px; max-width: 100%; }
.course-formula-plate > p { font-size: clamp(40px, 6vw, 90px); font-weight: 700; }
.course-lesson-register {
  grid-template-columns: minmax(0, 1fr); gap: 5px; max-height: 380px; overflow: auto;
  padding: 4px 8px 4px 4px; scrollbar-color: var(--md-outline) var(--md-surface);
}
.course-lesson-register .course-lesson-tile.practice-button {
  display: block; min-height: 58px; padding: 9px 13px; border-radius: 12px; box-shadow: none;
}
.course-lesson-register .course-lesson-tile.practice-button:hover { transform: none; }
.course-edition { margin-block: 14px; }
.unit-card-link:not(:has(.unit-card-art)) { grid-template-columns: minmax(0, 1fr); }
.lesson-layout.lesson-without-model { display: block; max-width: 770px; margin-inline: auto; }
.lesson-without-model > .lesson-actions { margin-top: 16px; }
.lesson-training { min-width: 0; }
.training-problem { padding-block: 12px; border-bottom: 1px solid var(--md-outline-variant); }
.training-problem > p { max-width: 68ch; line-height: 1.65; margin-block: 6px 12px; }
.training-problem .worked-example { margin: 0; }