@import url('https://unpkg.com/normalize.css') layer(normalize);

@layer normalize, base, demo, building-text, form, toc, transitions, alignment, theme-toggle, project-cards, stack-cards, morphing-faq, course-cards;

@layer building-text {
  :root {
    --cable: color-mix(in lch, canvasText, canvas 35%);
    --claw: color-mix(in lch, canvasText, canvas 15%);
    --head: color-mix(in lch, canvasText, canvas 25%);
    --delay: 1s;
    --speed: 2.4s;
    --base-delay: 1;
    --cross-delay: 0;
    --cross-speed: 2.8;
    --dot-delay: 0.8;
    --dot-speed: 4.4;
  }

  .building-header {
    position: relative;
  }

  .tagline {
    --font-level: 6;
    height: 1em;
    overflow: visible !important;
  }

  .construct {
    animation: slide-in var(--speed) var(--delay) ease-out both;
  }
  .claw {
    animation: slide-out var(--speed) var(--delay) ease-in both;
  }
  .claw path {
    animation: let-go var(--speed) var(--delay) ease-out both;
  }

  .construct--horizontal {
    --delay: calc((var(--base-delay) + var(--cross-delay)) * 1s);
    --speed: calc(var(--cross-speed) * 1s);
    --x: -100vmax;
  }
  .construct--vertical {
    --delay: calc((var(--base-delay) + var(--dot-delay)) * 1s);
    --speed: calc(var(--dot-speed) * 1s);
    --y: -150vmax;
  }

  @keyframes let-go {
    0%, 48% { rotate: var(--start); }
    50%, 100% { rotate: var(--end); }
  }
  @keyframes slide-in {
    0% { transform: translate(var(--x, 0), var(--y, 0)); }
    40%, 100% { transform: translate(0, 0); }
  }
  @keyframes slide-out {
    0%, 60% { transform: translate(0, 0); }
    100% { transform: translate(var(--x, 0), var(--y, 0)); }
  }

  .construct, .claw, .cross, .dot, .claw path {
    transform-box: fill-box;
  }

  .claw--horizontal { transform-origin: 50% 50%; }
  .claw path { stroke: var(--claw); }
  .claw line { stroke: var(--cable); }
  .claw circle { fill: var(--head); stroke: var(--head); }

  .claw--vertical path:nth-of-type(1) {
    transform-origin: 0 0; rotate: -25deg;
    --start: 0; --end: -25deg;
  }
  .claw--vertical path:nth-of-type(2) {
    transform-origin: 100% 0; rotate: 25deg;
    --start: 0; --end: 25deg;
  }
  .claw--horizontal path:nth-of-type(1) {
    transform-origin: 0 100%; rotate: 4deg;
    --start: 4deg; --end: -25deg;
  }
  .claw--horizontal path:nth-of-type(2) {
    transform-origin: 0 100%; rotate: -4deg;
    --start: -4deg; --end: 25deg;
  }
}

@layer alignment {
  [data-align='right'] {
    .container {
      grid-template-columns: 1fr auto;
    }
    table-of-contents {
      grid-column: 2;
      margin-right: 0;
      font-weight: 500;
      margin-left: 4rem;
      text-rendering: geometricPrecision;
    }
    header, main {
      max-width: fit-content;
      width: 60ch;
      grid-column: 1;
    }
    .container > hr, footer {
      grid-column: 1;
    }
  }
}

@layer transitions {
  table-of-contents {
    scroll-target-group: auto;
    a {
      transition-property: color;
      transition-duration: 0.26s;
      transition-timing-function: cubic-bezier(0.215, 0.610, 0.355, 1);
      color: light-dark(hsl(0 0% 60%), hsl(0 0% 40%));

      &:is(:hover, :focus-visible) {
        color: light-dark(hsl(0 0% 0%), hsl(0 0% 100%));
      }
    }

    nav > ol > li:first-of-type {
      anchor-name: --active;
    }
    :not([href='#pre']):target-current {
      anchor-name: --active;
      color: light-dark(var(--accent-light), var(--accent-dark));
      opacity: 1;
    }

    &:has(:not([href='#pre']):target-current)::after {
      opacity: 1;
    }

    &::after {
      opacity: 0;
      content: "";
      position: absolute;
      width: anchor-size(height);
      height: anchor-size(height);
      translate: -100% 0;
      background: light-dark(var(--accent-light), var(--accent-dark));
      border-radius: 0;
      scale: 0.25;
      position-anchor: --active;
      left: anchor(left);
      top: anchor(top);
      transition-property: top, left, opacity;
      transition-duration: 0.26s;
      transition-timing-function: cubic-bezier(0.215, 0.610, 0.355, 1);

      @supports (corner-shape: squircle) {
        corner-shape: squircle;
        border-radius: 100px;
      }
    }
  }
}

@layer toc {
  table-of-contents {
    position: sticky;
    align-self: start;
    top: 4rem;
    margin-right: 4rem;
    font-size: 0.875rem;

    [href='#pre'] {
      display: flex;
      align-items: center;
      gap: 0.25rem;
      padding-right: 0.5rem;
      text-transform: uppercase;
      font-size: 0.65rem;
      svg {
        width: 16px;
      }
    }
    .back-to-top {
      opacity: 0;
      pointer-events: none;
    }
    &:has(:not([href='#pre']):target-current) {
      .back-to-top {
        opacity: 1;
        pointer-events: all;
      }
      hr {
        opacity: 0.5;
      }
    }
    hr {
      opacity: 0;
      margin-top: 2rem;
    }
    hr, .back-to-top {
      transition: opacity 0.26s cubic-bezier(0.215, 0.610, 0.355, 1);
    }
    h2 {
      margin-top: 0;
      font-size: 0.875rem;
      font-weight: 500;
      text-transform: uppercase;
      position: absolute;
      bottom: 100%;
      margin-bottom: 0.25rem;
      font-size: 0.65rem;
      color: light-dark(#000, #fff);
    }
    nav ol {
      margin: 0;
      list-style: none;
      padding-left: 1rem;
    }
    nav a {
      text-decoration: none;
      color: inherit;
    }
    nav > ol {
      padding: 0;
    }

    nav a {
      display: block;
      padding-block: 0.25rem;
    }
  }

  html {
    scroll-behavior: smooth;
    scroll-padding-top: 2rem;
  }
}

@layer demo {
  html {
    display: grid;
    place-items: center;
    scrollbar-color: light-dark(var(--accent-light), var(--accent-dark)) #0000;
  }

  table-of-contents {
    grid-row: 2;
    margin-top: 0;
  }
  header {
    max-width: fit-content;
    width: 60ch;
    grid-column: 2;
  }
  body {
    display: block;
    font-family: 'Inter', sans-serif;
    color: light-dark(hsl(0 0% 24%), hsl(0 0% 98%));
    letter-spacing: -0.02em;
    align-content: start;
    place-items: start;
  }
  footer {
    width: 100%;
    grid-column: 2;

    & > p {
      font-size: 0.875rem;
      opacity: 0.7;
      text-align: center;
      padding-block: 2rem;
    }
  }
  .container {
    display: inline-grid;
    max-width: 100%;
    padding-inline: 1rem;
    grid-template-columns: auto 1fr;
  }
  main {
    grid-column: 2;
    width: 60ch;
    max-width: fit-content;
  }

  header {
    min-height: 50vh;
    display: grid;
    align-content: end;
    padding-block: 4rem;

    .author-info {
      display: block;
    }

    .author-line {
      display: block;
      margin: 0;
      font-size: 0.875rem;
      font-weight: 600;
      letter-spacing: 0.02em;
      opacity: 1;
      line-height: 1.35;
      white-space: normal;
    }

    .author {
      display: flex;
      align-items: center;
      gap: 1.5rem;
      font-weight: 400;
      font-size: 0.875rem;
    }
    img {
      width: 24px;
      aspect-ratio: 1;
      border-radius: 50%;
    }
  }
  section {
    margin-bottom: 6rem;

    &:last-of-type {
      margin-top: 6rem;
    }
  }

  h3 {
    margin-top: 2rem;
    margin-bottom: .5rem;
  }

  article p {
    line-height: 1.5;
    margin: 0;
  }

  article p:not(:last-of-type) {
    margin-bottom: 1rem;
  }

  h1 {
    --font-level: 4.5;
    line-height: 1;
    margin: 0;
    margin-bottom: 2rem;
    text-wrap: balance;
  }
}

@layer base {
  :root {
    --font-size-min: 16;
    --font-size-max: 20;
    --font-ratio-min: 1.2;
    --font-ratio-max: 1.33;
    --font-width-min: 375;
    --font-width-max: 1500;
    --accent-light: hsl(0, 100%, 56%);
    --accent-dark: hsl(164, 100%, 56%);
  }

  html {
    color-scheme: light dark;
  }

  [data-theme='light'] {
    color-scheme: light only;
  }

  [data-theme='dark'] {
    color-scheme: dark only;
  }

  :where(.fluid) {
    --fluid-min: calc(
      var(--font-size-min) * pow(var(--font-ratio-min), var(--font-level, 0))
    );
    --fluid-max: calc(
      var(--font-size-max) * pow(var(--font-ratio-max), var(--font-level, 0))
    );
    --fluid-preferred: calc(
      (var(--fluid-max) - var(--fluid-min)) /
        (var(--font-width-max) - var(--font-width-min))
    );
    --fluid-type: clamp(
      (var(--fluid-min) / 16) * 1rem,
      ((var(--fluid-min) / 16) * 1rem) -
        (((var(--fluid-preferred) * var(--font-width-min)) / 16) * 1rem) +
        (var(--fluid-preferred) * var(--variable-unit, 100vi)),
      (var(--fluid-max) / 16) * 1rem
    );
    font-size: var(--fluid-type);
  }

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

  body {
    background: light-dark(#fff, #000);
    display: grid;
    place-items: center;
    min-height: 100vh;
    font-family: 'SF Pro Text', 'SF Pro Icons', 'AOS Icons', 'Helvetica Neue',
      Helvetica, Arial, sans-serif, system-ui;
  }

  body::before {
    --size: 45px;
    --line: color-mix(in hsl, canvasText, transparent 90%);
    content: '';
    height: 100vh;
    width: 100vw;
    position: fixed;
    background: linear-gradient(
          90deg,
          var(--line) 1px,
          transparent 1px var(--size)
        )
        calc(var(--size) * 0.36) 50% / var(--size) var(--size),
      linear-gradient(var(--line) 1px, transparent 1px var(--size)) 0%
        calc(var(--size) * 0.32) / var(--size) var(--size);
    mask: linear-gradient(-200deg, transparent 50%, white);
    top: 0;
    transform-style: flat;
    pointer-events: none;
    z-index: -1;
  }


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

@layer form {
  .container > hr {
    grid-column: 2;
    width: 100%;
    margin-bottom: 6rem;
  }

  [data-waitlist-form] {
    margin-bottom: 6rem;
  }

  [data-waitlist-content] > p {
    margin-bottom: 1rem;
    margin-top: 0;
    line-height: 1.5;
    text-wrap: pretty;
  }

  [data-waitlist-content] > p strong {
    font-weight: 700;
    text-wrap: balance;
  }

  [data-controls] {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    justify-content: flex-end;
    gap: 0.5rem;
    margin-bottom: 1rem;
  }

  [data-controls] > div {
    flex: 1 1 0%;
    display: flex;
  }

  [data-controls] > div:last-child {
    position: relative;
  }

  [data-controls] input {
    border-radius: 0.375rem;
    border: 1px solid rgb(209 213 219);
    height: 2.25rem;
    padding-inline: 1rem;
    flex: 1 1 0%;
    min-width: 0;
    outline: none;
    color: canvasText;
  }

  [data-controls] input:focus-visible {
    border-color: light-dark(var(--accent-light), var(--accent-dark));
  }

  [data-controls] input::placeholder {
    font-size: 0.875rem;
    color: rgb(156 163 175);
  }

  [data-controls] button {
    position: relative;
    overflow: hidden;
    border-radius: 0.375rem;
    color: light-dark(#fff, #000);
    background: light-dark(hsl(0 0% 10%), hsl(0 0% 90%));
    box-shadow: inset 0 2px 4px 0 rgb(17 24 39 / 0.2);
    cursor: pointer;
    height: 2.25rem;
    display: grid;
    place-items: center;
    font-size: 0.875rem;
    padding-inline: 1rem;
  }

  [data-controls] button:active {
    transform: scale(0.98);
  }

  [data-controls] button::after {
    content: '';
    position: absolute;
    inset: 0;
    border-radius: 0.375rem;
    background: linear-gradient(180deg, rgb(255 255 255 / 0.4), rgb(255 255 255 / 0.1));
    opacity: 0.7;
  }

  [data-controls] button:hover::after {
    opacity: 1;
  }

  @media (prefers-reduced-motion: no-preference) {
    [data-controls] button,
    [data-controls] button::after {
      transition: all 0.2s;
    }
  }

  [data-waitlist-form] form > div:last-child {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    accent-color: light-dark(var(--accent-light), var(--accent-dark));
    font-size: 0.75rem;
  }
}

@layer theme-toggle {
  .theme-toggle {
    position: fixed;
    top: 1rem;
    right: 1rem;
    z-index: 100;
    width: 40px;
    height: 40px;
    border-radius: 50%;
    border: 1px solid color-mix(in hsl, canvasText, transparent 80%);
    background: light-dark(hsl(0 0% 100% / 0.8), hsl(0 0% 0% / 0.8));
    backdrop-filter: blur(8px);
    cursor: pointer;
    display: grid;
    place-items: center;
    color: canvasText;
    padding: 0;
    transition: border-color 0.2s, background 0.2s;
  }

  .theme-toggle:is(:hover, :focus-visible) {
    border-color: light-dark(var(--accent-light), var(--accent-dark));
  }

  .theme-toggle svg {
    width: 20px;
    height: 20px;
    position: absolute;
    transition: opacity 0.2s, transform 0.3s;
  }

  .theme-toggle__sun {
    opacity: 0;
    transform: rotate(-90deg) scale(0.5);
  }

  .theme-toggle__moon {
    opacity: 1;
    transform: rotate(0deg) scale(1);
  }

  [data-theme='dark'] .theme-toggle__sun {
    opacity: 1;
    transform: rotate(0deg) scale(1);
  }

  [data-theme='dark'] .theme-toggle__moon {
    opacity: 0;
    transform: rotate(90deg) scale(0.5);
  }

  [data-theme='light'] .theme-toggle__sun {
    opacity: 0;
    transform: rotate(-90deg) scale(0.5);
  }

  [data-theme='light'] .theme-toggle__moon {
    opacity: 1;
    transform: rotate(0deg) scale(1);
  }
}

@layer pricing-toggle {
  .pricing-section {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1.5rem;
    margin-bottom: 4rem;
  }

  .pricing-section h2 {
    margin: 0;
  }

  .control .indicator {
    position: absolute;
    width: 50%;
    left: 0;
    top: 0;
    bottom: 0;
    background: var(--toggle-primary);
    border-radius: 100px;
  }

  .control .premium .indicator {
    background: var(--toggle-primary);
    left: 50%;
    top: 0;
    translate: -50% 0;
  }

  :root {
    --toggle-shadow-color: 0deg 0% 63%;
    --toggle-primary: light-dark(hsl(0 0% 10%), #fff);
    --toggle-secondary: canvas;
    --toggle-inactive: light-dark(hsl(0 0% 60%), hsl(0 0% 50%));
    --toggle-duration: 0.22;
    --toggle-drop-off: 0.4;
    --toggle-ease: linear(
      0 0%, 0.2342 12.49%, 0.4374 24.99%,
      0.6093 37.49%, 0.6835 43.74%,
      0.7499 49.99%, 0.8086 56.25%,
      0.8593 62.5%, 0.9023 68.75%, 0.9375 75%,
      0.9648 81.25%, 0.9844 87.5%,
      0.9961 93.75%, 1 100%
    );
    --toggle-border: light-dark(hsl(0 0% 80%), hsl(0 0% 60%));

    @media (prefers-color-scheme: dark) {
      --toggle-shadow-color: 0deg 0% 0%;
    }
  }
  [data-theme='dark'] {
    --toggle-shadow-color: 0deg 0% 0%;
  }
  [data-theme='light'] {
    --toggle-shadow-color: 0deg 0% 63%;
  }

  .control .premium:has(:checked)::before {
    translate: -50% -250%;
    scale: 0.85;
  }
  .control .premium:has(:checked) label span {
    scale: 1;
  }
  .control .premium:has(:checked) .indicator {
    background: var(--toggle-secondary);
    clip-path: inset(0 0 0 0 round 100px);
  }
  .control .premium:has(:checked) label {
    color: var(--toggle-inactive);
    opacity: 0.75;
  }
  .control .premium:has(:nth-of-type(1):checked) label:nth-of-type(1),
  .control .premium:has(:nth-of-type(2):checked) label:nth-of-type(2) {
    color: var(--toggle-primary);
    opacity: 1;
  }
  .control .premium:has(:nth-of-type(1):checked) .indicator {
    translate: -100% 0;
  }
  .control .premium:has(:nth-of-type(2):checked) .indicator {
    translate: 0 0;
  }

  .control label {
    transition-property: color, opacity;
    transition-duration: calc(var(--toggle-duration) * 1s);
    transition-timing-function: var(--toggle-ease);
  }

  .control .control__track:not(:has(> :checked)) > label {
    color: var(--toggle-primary);
    opacity: var(--toggle-drop-off);
  }
  .control .control__track:not(:has(> :checked)) > .indicator {
    translate: 100% 0;
  }
  .control .indicator {
    transition: translate calc(var(--toggle-duration) * 1s) var(--toggle-ease);
  }
  .control .premium .indicator {
    transition-property: translate, clip-path, background;
    transition-duration: calc(var(--toggle-duration) * 1s);
    transition-timing-function: var(--toggle-ease);
    clip-path: inset(
      73cqh calc(50% + 1px) calc(27cqh - 2px) calc(50% - 3px) round 100px
    );
  }
  .control .premium::before {
    transition-property: scale, translate;
    transition-duration: calc(var(--toggle-duration) * 1s);
    transition-timing-function: var(--toggle-ease);
  }
  .control .control__track:has(> :checked) .premium .indicator {
    background: var(--toggle-inactive);
  }
  .control .control__track:has(> :checked) .premium label {
    color: var(--toggle-inactive);
  }

  .control {
    scale: 1.2;
    letter-spacing: 0.5px;
    position: relative;
    width: 260px;
    height: 38px;
    aspect-ratio: 300 / 38;
    background: var(--toggle-secondary);
    border-radius: 100px;
    border: 1px solid var(--toggle-border);
    padding: 2px;
    box-shadow: -0.1px 1px 1px hsl(var(--toggle-shadow-color) / 0.39),
      -0.2px 3.2px 3.1px -0.4px hsl(var(--toggle-shadow-color) / 0.36),
      -0.3px 5.7px 5.5px -0.8px hsl(var(--toggle-shadow-color) / 0.34),
      -0.5px 9.3px 8.9px -1.2px hsl(var(--toggle-shadow-color) / 0.32),
      -0.8px 14.8px 14.2px -1.6px hsl(var(--toggle-shadow-color) / 0.29),
      -1.3px 23.1px 22.2px -2px hsl(var(--toggle-shadow-color) / 0.27),
      -2px 35px 33.7px -2.4px hsl(var(--toggle-shadow-color) / 0.24),
      -2.9px 51.2px 49.2px -2.8px hsl(var(--toggle-shadow-color) / 0.22),
      -4.1px 72.6px 69.8px -3.2px hsl(var(--toggle-shadow-color) / 0.2),
      -5.6px 100px 96.2px -3.6px hsl(var(--toggle-shadow-color) / 0.17);
  }

  .control .control__track {
    display: grid;
    place-items: center;
    grid-template-columns: repeat(4, 1fr);
    width: 100%;
    height: 100%;
    position: relative;
  }

  .control .premium::before {
    content: '';
    position: absolute;
    left: 50%;
    top: 50%;
    translate: -50% -80%;
    color: var(--toggle-primary);
    font-size: 0.75rem;
    z-index: 2;
  }

  .control label {
    display: inline-block;
    height: 100%;
    width: 100%;
    display: grid;
    place-items: center;
    cursor: pointer;
    font-size: 0.75rem;
    color: var(--toggle-primary);
    z-index: 2;
  }

  .control .control__track > label {
    color: var(--toggle-secondary);
  }

  .control .premium {
    width: 100%;
    height: 100%;
    display: grid;
    position: relative;
    grid-template-columns: 1fr 1fr;
    border: 1px solid #0000;
    container-type: size;
  }

  .control .premium,
  .control .control__track > label:nth-of-type(1) {
    grid-column: span 2;
  }

  .control label span {
    display: grid;
    place-items: center;
    height: 100%;
    width: 100%;
    transition: scale calc(var(--toggle-duration) * 1s) var(--toggle-ease);
  }

  .control .premium label:nth-of-type(1) span {
    scale: 0.75;
    transform-origin: 150% 150%;
    border-radius: 100px;
  }
  .control .premium label:nth-of-type(2) span {
    scale: 0.75;
    transform-origin: -65% 150%;
    border-radius: 100px;
  }
}

@layer skill-panels {
  .skill-panels {
    width: 100%;
    max-width: 520px;
    display: grid;
  }

  .skill-panel {
    grid-area: 1 / 1;
    opacity: 0;
    transform: translateY(8px);
    transition: opacity 0.35s ease, transform 0.35s ease;
    pointer-events: none;
    display: flex;
    flex-direction: column;
    gap: 1rem;
    padding: 1.5rem;
    border-radius: 16px;
    border: 1px solid color-mix(in hsl, canvasText, transparent 80%);
    background: light-dark(hsl(0 0% 98%), hsl(0 0% 6%));
    visibility: hidden;
  }

  .skill-panel.active {
    opacity: 1;
    transform: translateY(0);
    pointer-events: auto;
    visibility: visible;
  }

  .skill-panel__header {
    display: flex;
    align-items: center;
    gap: 0.75rem;
  }

  .skill-panel__header svg {
    flex-shrink: 0;
    color: #FF1E1E;
  }

  .skill-panel__header h3 {
    margin: 0;
    font-size: 1.15rem;
  }

  .skill-panel p {
    margin: 0;
    font-size: 0.925rem;
    line-height: 1.6;
    opacity: 0.8;
  }

  .skill-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    list-style: none;
    padding: 0;
    margin: 0.25rem 0 0;
  }

  .skill-tags li {
    font-size: 0.75rem;
    font-weight: 500;
    padding: 0.3rem 0.7rem;
    border-radius: 100px;
    background: light-dark(hsl(0 0% 90%), hsl(0 0% 16%));
    color: light-dark(hsl(0 0% 30%), hsl(0 0% 70%));
    white-space: nowrap;
  }
}

@layer project-cards {
  .projects-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 1rem;
    margin-top: 1.5rem;
  }

  .project-card {
    display: block;
    position: relative;
    padding: 1.5rem;
    border-radius: 16px;
    border: 1px solid color-mix(in hsl, canvasText, transparent 80%);
    background: light-dark(hsl(0 0% 98%), hsl(0 0% 6%));
    text-decoration: none;
    color: inherit;
    transition: border-color 0.2s, transform 0.2s;
  }

  .project-card:hover {
    border-color: light-dark(var(--accent-light), var(--accent-dark));
    transform: translateY(-2px);
  }

  .project-card--current {
    border-color: color-mix(in hsl, light-dark(var(--accent-light), var(--accent-dark)), transparent 50%);
  }

  .project-card__badge {
    display: inline-block;
    font-size: 0.7rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    padding: 0.2rem 0.55rem;
    border-radius: 100px;
    background: color-mix(in hsl, light-dark(var(--accent-light), var(--accent-dark)), transparent 82%);
    color: light-dark(var(--accent-light), var(--accent-dark));
    margin-bottom: 0.75rem;
  }

  .project-card h3 {
    margin: 0 0 0.5rem;
    font-size: 1.2rem;
  }

  .project-card p {
    margin: 0 0 1rem;
    font-size: 0.9rem;
    line-height: 1.6;
    opacity: 0.75;
  }

  .project-card__img {
    width: 100%;
    aspect-ratio: 16 / 10;
    object-fit: cover;
    object-position: top;
    border-radius: 10px;
    border: 1px solid color-mix(in hsl, canvasText, transparent 88%);
    margin-bottom: 1rem;
    transition: transform 0.3s ease, filter 0.3s ease;
    filter: grayscale(0.2);
  }

  .project-card:hover .project-card__img {
    transform: scale(1.02);
    filter: grayscale(0);
  }

  .project-card__url {
    font-size: 0.8rem;
    font-family: 'Geist Mono', monospace;
    opacity: 0.5;
    transition: opacity 0.2s;
  }

  .project-card:hover .project-card__url {
    opacity: 1;
  }
}

@layer stack-cards {
  .stack-section {
    margin-bottom: 4rem;
  }

  .stack-section h2 {
    margin-top: 0;
    margin-bottom: 1.5rem;
  }

  .stack-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 1rem;
  }

  .stack-card {
    padding: 1.5rem;
    border-radius: 16px;
    border: 1px solid color-mix(in hsl, canvasText, transparent 80%);
    background: light-dark(hsl(0 0% 98%), hsl(0 0% 6%));
    transition: border-color 0.2s;
  }

  .stack-card:hover {
    border-color: light-dark(var(--accent-light), var(--accent-dark));
  }

  .stack-card h3 {
    margin: 0 0 0.5rem;
    font-size: 1.1rem;
  }

  .stack-card p {
    margin: 0 0 1rem;
    font-size: 0.925rem;
    line-height: 1.6;
    opacity: 0.8;
  }
}

@layer morphing-faq {
  .faq-section {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1.5rem;
  }

  .faq-section > h2 {
    margin: 0;
    align-self: flex-start;
  }

  .morphing-disclosure {
    --faq-background: light-dark(#fff, hsl(0 0% 4%));
    --faq-hover-background: light-dark(hsl(0 0% 94%), hsl(0 0% 8%));
    --faq-border: light-dark(hsl(0 0% 80%), hsl(0 0% 20%));
    --faq-border-width: 1px;
    --faq-border-color: var(--faq-border);
    --faq-bounce: linear(
      0 0%, 0.5571 7.53%, 0.8252 11.98%,
      0.9337 14.38%, 1.0166 16.8%,
      1.0765 19.31%, 1.1146 21.97%,
      1.1263 23.47%, 1.1325 25.06%,
      1.133 26.76%, 1.128 28.62%,
      1.1094 31.9%, 1.0484 39.77%,
      1.0218 43.85%, 1.0011 48.42%,
      0.9895 53.23%, 0.9861 59.8%,
      1 81.27% 100%
    );
    --faq-bounce-duration: 1s;
    --faq-duration: 0.26s;
    --faq-ease: linear(
      0 0%, 0.2688 9.91%, 0.3859 15%,
      0.4917 20.19%, 0.5865 25.5%,
      0.6705 30.93%, 0.7441 36.51%,
      0.8075 42.26%, 0.8593 47.98%,
      0.9022 53.93%, 0.9366 60.13%,
      0.963 66.67%, 0.9812 73.4%,
      0.9929 80.76%, 0.9986 88.89%, 1 100%
    );
    --faq-blur: 4;
    --faq-translate-y: 1;
    --faq-opacity: 0.4;
    --faq-translate-margin: 1.5;
  }

  .morphing-disclosure {
    width: 100%;
    max-width: 100%;
    letter-spacing: -0.025em;
    line-height: 1.5;
    font-size: 0.875rem;
    transform-style: preserve-3d;
    perspective: 120px;
  }

  .morphing-disclosure .content,
  .morphing-disclosure summary {
    padding: 1rem;
  }

  .morphing-disclosure summary {
    padding-block: 0.875rem;
    display: grid;
    grid-template-columns: auto 1fr auto;
    gap: 1rem;
    align-items: center;

    svg {
      width: 16px;
      opacity: 0.7;

      &:first-of-type {
        width: 18px;
      }

      &:last-of-type {
        transition-property: rotate, opacity;
        transition-duration: var(--faq-duration);
        transition-timing-function: var(--faq-ease);
      }
    }
  }

  .morphing-disclosure details[open] summary svg:last-of-type {
    rotate: 225deg;
  }

  .morphing-disclosure summary::marker {
    font-size: 0px;
  }

  .morphing-disclosure .content {
    padding-top: 0;
    translate: 0 calc(var(--faq-translate-y) * 1rem);
    opacity: var(--faq-opacity);
    filter: blur(calc(var(--faq-blur) * 1px));
    color: color-mix(in hsl, currentColor, #0000 30%);

    p {
      padding: 0;
      margin: 0;
    }
  }

  .morphing-disclosure details {
    background: var(--faq-background);
    border-inline: var(--faq-border-width) solid var(--faq-border-color);
    position: relative;

    summary {
      -webkit-tap-highlight-color: #0000;
      cursor: pointer;

      &::after {
        content: '';
        position: absolute;
        inset: 0;
        z-index: 2;
      }
    }
  }

  .morphing-disclosure details:has(summary:hover) {
    background: var(--faq-hover-background);

    summary svg:last-of-type {
      opacity: 1;
    }
  }

  .faq-section[data-style='border'] details:first-of-type {
    border-top: var(--faq-border-width) solid var(--faq-border-color);
  }
  .faq-section[data-style='border'] details:last-of-type {
    border-bottom: var(--faq-border-width) solid var(--faq-border-color);
  }

  .morphing-disclosure details:first-of-type {
    border-radius: 1rem 1rem 0 0;

    summary::after {
      border-radius: 1rem 1rem 0 0;
    }
  }
  .morphing-disclosure details:last-of-type {
    border-radius: 0 0 1rem 1rem;

    summary::after {
      border-radius: 0 0 1rem 1rem;
    }
  }
  .morphing-disclosure details:has(+ details[open]) {
    border-bottom-left-radius: 1rem;
    border-bottom-right-radius: 1rem;

    summary::after {
      border-bottom-left-radius: 1rem;
      border-bottom-right-radius: 1rem;
    }
  }
  .morphing-disclosure details[open] + details {
    border-top-left-radius: 1rem;
    border-top-right-radius: 1rem;

    summary::after {
      border-top-left-radius: 1rem;
      border-top-right-radius: 1rem;
    }
  }

  .morphing-disclosure details[open] {
    margin-block: calc(var(--faq-translate-margin) * 1rem);
    border-radius: 1rem;
    z-index: 2;

    summary::after {
      border-radius: 1rem;
    }

    &:first-of-type {
      margin-block-start: 0;
    }
    &:last-of-type {
      margin-block-end: 0;
    }
  }

  .faq-section[data-bordered='true'] .morphing-disclosure details {
    border-block-end: var(--faq-border-width) solid var(--faq-border-color);
    border-block-start: var(--faq-border-width) solid var(--faq-border-color);
    transform: translate(0, calc(var(--faq-border-width) * (var(--level, 1) - 1)));
    z-index: var(--level, 1);

    &[open],
    &[open] + details,
    &:first-of-type {
      border-block-start-color: var(--faq-border-color);
    }
  }

  .faq-section[data-bordered='true'] .morphing-disclosure details:has(+ details + details[open]) { --level: 2; }
  .faq-section[data-bordered='true'] .morphing-disclosure details:has(+ details + details + details[open]) { --level: 3; }
  .faq-section[data-bordered='true'] .morphing-disclosure details:has(+ details + details + details + details[open]) { --level: 4; }

  .faq-section[data-bordered='true'] .morphing-disclosure details[open] + details + details { --level: 0; }
  .faq-section[data-bordered='true'] .morphing-disclosure details[open] + details + details + details { --level: -1; }
  .faq-section[data-bordered='true'] .morphing-disclosure details[open] + details + details + details + details { --level: -2; }

  .faq-section[data-bordered='true'] .morphing-disclosure:not(:has([open])) details {
    &:nth-of-type(2) { --level: 0; }
    &:nth-of-type(3) { --level: -1; }
    &:nth-of-type(4) { --level: -2; }
    &:nth-of-type(5) { --level: -3; }
  }

  .faq-section[data-translate='true'] .morphing-disclosure details[open] {
    margin-block: 0;
  }
  .faq-section[data-translate='true'] .morphing-disclosure details:has(~ details[open]) {
    translate: 0 calc(var(--faq-translate-margin) * -1rem);
  }
  .faq-section[data-translate='true'] .morphing-disclosure details[open] ~ details {
    translate: 0 calc(var(--faq-translate-margin) * 1rem);
  }

  .faq-section[data-highlight='true'] .morphing-disclosure details[open] {
    --faq-border-color: light-dark(#000, #fff);
  }

  .morphing-disclosure details {
    transition-property: border-radius, margin, background-color, border-color, border-width, transform, translate, opacity, color;
    transition-duration: var(--faq-duration);
    transition-timing-function: var(--faq-ease);
    transform: translateZ(0);
  }

  .morphing-disclosure .content {
    transition-property: translate, opacity, filter;
    transition-duration: var(--faq-duration);
    transition-timing-function: var(--faq-ease);
    transform: translateZ(0);
  }

  .morphing-disclosure details::details-content {
    height: 0;
    transition-property: content-visibility, height;
    transition-behavior: allow-discrete;
    transition-duration: var(--faq-bounce-duration);
    transition-timing-function: var(--faq-bounce);
    overflow: hidden;
  }

  .morphing-disclosure details,
  .morphing-disclosure details::details-content {
    interpolate-size: allow-keywords;
  }

  .morphing-disclosure details[open]::details-content {
    height: var(--content-height);
  }

  @supports (interpolate-size: allow-keywords) {
    .morphing-disclosure details[open]::details-content {
      height: fit-content;
    }
  }

  .morphing-disclosure details[open] .content {
    translate: 0 0;
    opacity: 1;
    filter: blur(0);
  }
}

@layer course-cards {
  .courses-section {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1rem;
    margin-bottom: 4rem;
  }

  .courses-section h2 {
    margin: 0;
    text-transform: lowercase;
  }

  .courses-intro {
    width: 74ch;
    max-width: 100%;
    text-wrap: balance;
    font-family: monospace;
    margin-bottom: 2rem;
    line-height: 1.5;
    opacity: 0.8;
    font-weight: 400;
  }

  .course-list :is(svg, h3) {
    opacity: 0.6;
    transition: opacity calc(var(--card-speed) * 1.2) var(--card-easing);
  }

  .course-list :is(a, p) {
    opacity: 0;
    transition: opacity calc(var(--card-speed) * 1.2) var(--card-easing);
    width: fit-content;
  }

  .course-list img {
    filter: grayscale(1) brightness(1.5);
    scale: 1.1;
    transition-property: filter, scale;
    transition-duration: calc(var(--card-speed) * 1.2);
    transition-timing-function: var(--card-easing);
  }

  .course-list [data-active='true'] :is(a, p, h3, svg) {
    opacity: var(--card-opacity, 1);
  }
  .course-list [data-active='true'] :is(a, p) {
    transition-delay: calc(var(--card-speed) * 0.25);
  }

  .course-list [data-active='true'] img {
    filter: grayscale(0) brightness(1);
    scale: 1;
    transition-delay: calc(var(--card-speed) * 0.25);
  }

  .course-list article {
    width: calc(var(--article-width) * 1px);
    height: 100%;
    position: absolute;
    font-family: monospace;
    top: 0;
    left: 0;
    display: flex;
    flex-direction: column;
    justify-content: flex-end;
    gap: 1rem;
    padding-inline: calc(var(--card-base) * 0.5 - 9px);
    padding-bottom: 1rem;
    overflow: hidden;
  }

  .course-list article h3 {
    position: absolute;
    top: 1rem;
    left: calc(var(--card-base) * 0.5);
    transform-origin: 0 50%;
    rotate: 90deg;
    font-size: 1rem;
    font-weight: 300;
    text-transform: uppercase;
    font-family: monospace;
    white-space: nowrap;
    margin: 0;
  }

  .course-list article svg {
    width: 18px;
    fill: none;
  }

  .course-list article p {
    font-size: 13px;
    text-wrap: balance;
    line-height: 1.25;
    --card-opacity: 0.8;
  }

  .course-list article a {
    position: absolute;
    bottom: 1rem;
    height: 18px;
    line-height: 1;
    color: inherit;
  }

  .course-list article a:is(:focus-visible, :hover) {
    outline: none;
  }

  .course-list article a:is(:focus-visible, :hover) span {
    text-decoration: underline;
    text-underline-offset: 4px;
  }

  .course-list article a span {
    display: inline-block;
    line-height: 18px;
    translate: calc(var(--card-base) * 0.5);
    font-weight: 500;
  }

  .course-list article img {
    position: absolute;
    pointer-events: none;
    inset: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
    mask: radial-gradient(100% 100% at 100% 0, #fff, #0000);
  }

  :root {
    --card-gap: 8px;
    --card-base: clamp(2rem, 8cqi, 80px);
    --card-easing: linear(
      0 0%,
      0.1538 4.09%,
      0.2926 8.29%,
      0.4173 12.63%,
      0.5282 17.12%,
      0.6255 21.77%,
      0.7099 26.61%,
      0.782 31.67%,
      0.8425 37%,
      0.8887 42.23%,
      0.9257 47.79%,
      0.9543 53.78%,
      0.9752 60.32%,
      0.9883 67.11%,
      0.9961 75%,
      1 100%
    );
    --card-speed: 0.6s;
  }

  .course-list {
    display: grid;
    container-type: inline-size;
    grid-template-columns: 10fr 1fr 1fr;
    gap: var(--card-gap);
    list-style-type: none;
    justify-content: center;
    padding: 0;
    height: clamp(300px, 40dvh, 474px);
    margin: 0;
    width: 820px;
    max-width: 100%;
    transition: grid-template-columns var(--card-speed) var(--card-easing);
  }

  .course-list li {
    background: light-dark(#fff, #000);
    position: relative;
    overflow: hidden;
    min-width: var(--card-base);
    border-radius: 8px;
    border: 1px solid color-mix(in hsl, canvas, canvasText 50%);
  }
}

/* PiP Demo Block */
.pip-demo {
  --gutter: 1;
  --margin: 0.1;
  --content-width: 640px;
  --nav-height: 56px;
  --width: 260;
  --duration: 0.26;
  --threshold: calc(
    (min(var(--content-width) + 4rem, 100vw - 2rem) * (9 / 16) * var(--margin)) * -1
  );

  grid-column: 1;
  position: relative;
}

/* Sticky nav */
.pip-nav {
  height: var(--nav-height);
  position: sticky;
  top: 0;
  width: 100%;
  background: light-dark(canvas, #000);
  z-index: 9999;
  animation: pip-nav-elevate linear both;
  animation-timeline: scroll(root);
  animation-range: 0 calc(var(--nav-height) * 2);
}

@keyframes pip-nav-elevate {
  to {
    box-shadow: 0px 0.6px 0.7px hsl(0 0% 0% / 0.05),
      0px 1.6px 1.8px -0.6px hsl(0 0% 0% / 0.05),
      0px 12.6px 14.2px -2.5px hsl(0 0% 0% / 0.05);
  }
}

.pip-nav__content {
  width: var(--content-width);
  max-width: calc(100% - 2rem);
  margin: 0 auto;
  height: 100%;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.pip-nav__content > a {
  display: grid;
  place-items: center;
  width: 40px;
  aspect-ratio: 1;
  color: inherit;
  text-decoration: none;
}

.pip-nav__content > a svg { width: 24px; }

.pip-nav nav ul {
  padding: 0;
  margin: 0;
  display: flex;
  list-style-type: none;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.875rem;
}

.pip-nav nav ul a {
  text-decoration: none;
  color: inherit;
  cursor: pointer;
}

/* Video backdrop placeholder */
.pip-backdrop {
  width: calc(var(--content-width) + 4rem);
  aspect-ratio: 16 / 9;
  position: absolute;
  top: var(--nav-height);
  background: color-mix(in oklch, canvas, canvasText 2%);
  box-shadow: inset 0 -2px 6px -2px color-mix(in oklch, canvasText, transparent 80%);
  left: 50%;
  translate: -50% 0;
  border-radius: 1rem;
}

.pip-sentinel {
  position: absolute;
  height: 2px;
  width: calc(100% + 4rem);
  left: 50%;
  translate: -50% -50%;
  top: calc(var(--threshold) * -1);
  opacity: 0;
  pointer-events: none;
}

/* Sticky video container */
.pip-video-container {
  width: calc(var(--content-width) + 4rem);
  max-width: calc(100vw - 2rem);
  aspect-ratio: 16 / 9;
  margin: 0 auto;
  position: sticky;
  top: var(--threshold);
  z-index: 10;
  pointer-events: none;
  container-type: scroll-state;
}

.pip-video-container iframe {
  pointer-events: all;
  border-radius: 1rem;
  width: 100%;
  aspect-ratio: 16 / 9;
  position: absolute;
  left: 50%;
  top: 0;
  transform: translate(-50%, 0%);
  border: none;
  transition-property: width, transform, box-shadow, border-radius;
  transition-timing-function: ease-out;
  transition-duration: calc(var(--duration) * 1s);
}

/* CSS scroll-state PiP */
@container scroll-state(stuck: top) {
  .pip-video-container iframe {
    width: calc(var(--width) * 1px);
    border-radius: 6px;
    transition-timing-function: ease-in-out;
    box-shadow: 0px 0.6px 0.7px hsl(0 0% 0% / 0.1),
      0px 1.6px 1.8px -0.6px hsl(0 0% 0% / 0.1),
      0px 3.2px 3.6px -1.2px hsl(0 0% 0% / 0.1),
      0px 6.5px 7.3px -1.9px hsl(0 0% 0% / 0.1),
      0px 12.6px 14.2px -2.5px hsl(0 0% 0% / 0.1);
    transform: translate(-50%, 0%)
      translate(
        calc(50vw - (50% + (var(--gutter) * 1rem))),
        calc((100vh - var(--threshold)) - (100% + (var(--gutter) * 1rem)))
      );
  }
}

/* JS fallback */
.pip-demo[data-stuck='true'] .pip-video-container iframe {
  width: calc(var(--width) * 1px);
  border-radius: 6px;
  transition-timing-function: ease-in-out;
  box-shadow: 0px 0.6px 0.7px hsl(0 0% 0% / 0.1),
    0px 1.6px 1.8px -0.6px hsl(0 0% 0% / 0.1),
    0px 3.2px 3.6px -1.2px hsl(0 0% 0% / 0.1),
    0px 6.5px 7.3px -1.9px hsl(0 0% 0% / 0.1),
    0px 12.6px 14.2px -2.5px hsl(0 0% 0% / 0.1);
  transform: translate(-50%, 0%)
    translate(
      calc(50vw - (50% + (var(--gutter) * 1rem))),
      calc((100vh - var(--threshold)) - (100% + (var(--gutter) * 1rem)))
    );
}

/* Scrollable content */
.pip-body {
  width: var(--content-width);
  max-width: calc(100% - 2rem);
  margin: 0 auto;
  line-height: 1.5;
  font-size: 0.875rem;
}

.pip-body p {
  color: color-mix(in oklch, canvasText, canvas 36%);
  margin: 0;
}

.pip-body p:not(:last-of-type):not(:has(+ ul)) { margin-bottom: 2rem; }
.pip-body p:has(+ ul) { margin-bottom: 0.5rem; }

.pip-body ul {
  margin-bottom: 2rem;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  margin-top: 0.25rem;
  padding-left: 0.5rem;
  list-style-position: inside;
  color: color-mix(in oklch, canvasText, canvas 36%);
}

.pip-header {
  padding-block: 4rem;
}

.pip-title {
  margin: 0 0 1rem;
  font-family: 'Inter', sans-serif;
  font-size: 2rem;
  font-weight: 500;
  letter-spacing: -0.05em;
  line-height: 1;
}

.pip-header p {
  font-size: 1.25rem;
  margin: 0;
  text-wrap: balance;
  color: color-mix(in oklch, canvasText, canvas 36%);
}

.pip-hr {
  border-color: color-mix(in oklch, canvas, canvasText 10%);
  margin-bottom: 2rem;
}

.pip-footer-bar {
  width: var(--content-width);
  max-width: calc(100% - 2rem);
  margin: 6rem auto 0;
  padding-block: 2rem;
  opacity: 0.7;
  font-size: 0.875rem;
  text-align: center;
}

.examples-section {
  text-align: center;
  padding: 2rem 0;
}

.examples-section > p {
  margin-bottom: 2rem;
  opacity: 0.7;
}

.examples-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 1.5rem;
  text-align: left;
}

.example-card {
  display: block;
  padding: 1.5rem;
  border-radius: 12px;
  border: 1px solid color-mix(in hsl, canvasText, transparent 80%);
  background: light-dark(hsl(0 0% 98%), hsl(0 0% 8%));
  text-decoration: none;
  color: canvasText;
  transition: border-color 0.2s, transform 0.2s;
}

.example-card:hover {
  border-color: color-mix(in hsl, canvasText, transparent 40%);
  transform: translateY(-2px);
}

.example-card__icon {
  font-size: 2rem;
  margin-bottom: 0.75rem;
}

.example-card h3 {
  margin: 0 0 0.5rem;
  font-size: 1.1rem;
}

.example-card p {
  margin: 0;
  font-size: 0.875rem;
  opacity: 0.7;
  line-height: 1.5;
}

.example-card code {
  font-size: 0.8rem;
  background: light-dark(hsl(0 0% 90%), hsl(0 0% 20%));
  padding: 0.1rem 0.3rem;
  border-radius: 3px;
}

.example-card__link {
  display: inline-block;
  margin-top: 1rem;
  font-size: 0.875rem;
  font-weight: 600;
  color: #FF1E1E;
}

/* ── Mobile ─────────────────────────────────────────────── */
@media (max-width: 768px) {

  /* Collapse two-column grid to single block flow */
  .container {
    display: block;
    padding-inline: 1.25rem;
  }

  /* Hide the TOC sidebar — no room on mobile */
  table-of-contents {
    display: none;
  }

  /* Full-width content areas */
  header,
  main,
  footer,
  .pip-demo,
  .container > hr {
    width: 100% !important;
    max-width: 100% !important;
  }

  /* Header: shorter hero, tighter padding */
  header.building-header {
    min-height: 30vh;
    padding-block: 2rem;
  }

  /* Sections: reduce bottom margin */
  article section {
    margin-bottom: 3rem !important;
  }

  /* Intro paragraph */
  article p.intro {
    font-size: 1rem;
  }

  /* Skill panels: full width */
  .skill-panels {
    max-width: 100%;
  }

  /* What I Bring toggle: full width */
  .control {
    width: 100%;
  }

  /* Course cards: horizontal scroll so the interaction still works */
  .courses-section {
    align-items: flex-start;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    padding-bottom: 0.5rem;
  }

  .course-list {
    max-width: none;
    width: clamp(480px, 90vw, 700px);
    height: clamp(220px, 35dvh, 360px);
  }

  /* Examples grid: single column */
  .examples-grid {
    grid-template-columns: 1fr;
  }

  /* pip-demo: make video fill the width */
  .pip-demo {
    --content-width: min(640px, calc(100vw - 2.5rem));
  }

  /* pip-body padding on mobile */
  .pip-body,
  .pip-header,
  .pip-footer-bar {
    padding-inline: 0;
  }

  /* pip nav: already width 100%, just ensure it spans the viewport */
  .pip-nav {
    width: 100vw;
    margin-left: -1.25rem;
  }

  /* Footer contact buttons: stack vertically */
  [data-waitlist-form] [data-controls] {
    flex-direction: column;
    align-items: stretch;
  }

  [data-waitlist-form] [data-controls] a {
    text-align: center;
    width: 100%;
    box-sizing: border-box;
  }

  /* Theme toggle: adjust position */
  .theme-toggle {
    top: 0.75rem;
    right: 0.75rem;
  }
}