/* Shared microinteractions: short feedback, one service-section entrance. */
:root {
  --motion-ease: cubic-bezier(.16, 1, .3, 1);
  --motion-fast: 180ms;
}
.button, .menu-toggle {
  transition: transform var(--motion-fast) var(--motion-ease), background 220ms ease, border-color 220ms ease, box-shadow 220ms ease;
}
.button:focus-visible, .menu-toggle:focus-visible {
  box-shadow: 0 5px 16px rgb(0 0 0 / 18%);
}
.button:active, .menu-toggle:active {
  transform: translateY(1px) scale(.98);
}
.text-link, .site-nav > a:not(.button), .footer-nav a, .article-toc a {
  position: relative;
  transition: color var(--motion-fast) ease;
}
.text-link::after, .site-nav > a:not(.button)::after, .footer-nav a::after {
  content: '';
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 1px;
  background: var(--accent);
  transform: scaleX(0);
  transform-origin: right;
  transition: transform 260ms var(--motion-ease);
  pointer-events: none;
}
.text-link:focus-visible::after, .site-nav > a:focus-visible::after, .footer-nav a:focus-visible::after {
  transform: scaleX(1);
  transform-origin: left;
}
.hero-copy .text-link::after { display: none; }
.project-image, .hero-project img, .service-visual img, .article-image img {
  transition: transform 450ms var(--motion-ease), filter 300ms ease;
}
.project-link:focus-visible .project-image, .service-visual:focus-visible img, .article-image:focus-visible img {
  filter: brightness(1.08);
}
.project-meta > span { transition: transform 240ms var(--motion-ease); }
.plan {
  transition: background 240ms ease, border-color 240ms ease;
}
.plan:focus-within { background: rgb(255 255 255 / 3%); }
.plan h3 { transition: color 200ms ease; }
.plan:focus-within h3 { color: var(--accent); }
summary { transition: color 180ms ease, background 180ms ease; }
summary:focus-visible { color: var(--accent); }
.topic-links a, input, textarea, select {
  transition: border-color 180ms ease, background 180ms ease;
}
input:focus, textarea:focus, select:focus { border-color: var(--accent); }
@media (hover: hover) and (pointer: fine) {
  .button:hover, .menu-toggle:hover { transform: translateY(-2px); }
  .button:hover { box-shadow: 0 6px 18px rgb(0 0 0 / 20%); }
  .button:active, .menu-toggle:active { transform: translateY(1px) scale(.98); }
  .menu-toggle:hover { background: var(--surface); border-color: var(--accent); }
  .text-link:hover::after, .site-nav > a:hover::after, .footer-nav a:hover::after {
    transform: scaleX(1);
    transform-origin: left;
  }
  .project-link:hover .project-image, .service-visual:hover img { transform: scale(.985); filter: brightness(1.08); }
  .hero-project:hover img, .article-image:hover img { transform: scale(1.035); }
  .project-link:hover .project-meta > span { transform: translateX(4px); }
  .plan:hover { background: rgb(255 255 255 / 3%); }
  .plan:hover h3 { color: var(--accent); }
  summary:hover { color: var(--accent); background: rgb(255 255 255 / 2%); }
}
@keyframes menu-enter {
  from { opacity: .85; transform: translateY(-8px); }
  to { opacity: 1; transform: none; }
}
@media (prefers-reduced-motion: no-preference) {
  .site-nav.is-open { animation: menu-enter 220ms var(--motion-ease); }
}
@media (prefers-reduced-motion: reduce) {
  /* Keep immediate color/focus feedback, remove spatial movement. */
  .button, .menu-toggle, .project-image, .hero-project img, .service-visual img,
  .article-image img, .project-meta > span { transform: none !important; }
  *, *::before, *::after { animation: none !important; transition: none !important; }
}
/* Preserve a quiet underline at rest; accent grows across it on interaction. */
.text-link { border-bottom-color: var(--line); }
@media (hover: none) {
  .button:hover, .hero-project:hover img { transform: none; }
}

/* Reference button choreography: expanding circular fill + arrow exchange. */
.button {
  --button-fill: #c64436;
  --button-rest: var(--button);
  --button-rest-ink: #fff;
  position: relative;
  isolation: isolate;
  overflow: hidden;
  gap: 10px;
  background: var(--button-rest);
  color: var(--button-rest-ink);
  transition: color 300ms ease, border-color 300ms ease;
}
.button.secondary { --button-rest: var(--surface); --button-fill: var(--button); }
.site-nav .button { --button-rest: #fff; --button-rest-ink: #0b0f10; --button-fill: var(--button); }
.button::before {
  content: '';
  position: absolute;
  width: 220%;
  aspect-ratio: 1;
  left: 50%;
  top: 50%;
  border-radius: 50%;
  background: var(--button-fill);
  transform: translate(-50%, -50%) scale(0);
  transition: transform 800ms ease;
  pointer-events: none;
  z-index: -1;
}
.button-label {
  display: inline-block;
  position: relative;
  transition: transform 300ms ease;
}
.button-arrow {
  display: inline-flex;
  width: 16px;
  height: 16px;
  flex: 0 0 16px;
  pointer-events: none;
  transition: transform 300ms ease, opacity 300ms ease;
}
.button-arrow svg { display: block; width: 100%; height: 100%; }
.button-arrow-in {
  position: absolute;
  left: 24px;
  opacity: 0;
  transform: translateX(-42px);
}
/* Suppress the previous lift and shadow in every interaction state. */
.button:hover, .button:focus-visible, .button:active,
.button.secondary:hover, .site-nav .button:hover {
  transform: none;
  box-shadow: none;
  background: var(--button-rest);
}
.button:focus-visible { color: #fff; }
.button:focus-visible::before { transform: translate(-50%, -50%) scale(1); }
.button:focus-visible .button-label { transform: translateX(26px); }
.button:focus-visible .button-arrow-in { opacity: 1; transform: translateX(0); }
.button:focus-visible .button-arrow-out { opacity: 0; transform: translateX(42px); }
@media (hover: hover) and (pointer: fine) {
  .button:hover { color: #fff; }
  .button:hover::before { transform: translate(-50%, -50%) scale(1); }
  .button:hover .button-label { transform: translateX(26px); }
  .button:hover .button-arrow-in { opacity: 1; transform: translateX(0); }
  .button:hover .button-arrow-out { opacity: 0; transform: translateX(42px); }
}
.button:active::before { transform: translate(-50%, -50%) scale(1); }
.button:active { color: #fff; }
@media (max-width: 760px) { .button-arrow-in { left: 16px; } }
@media (prefers-reduced-motion: reduce) {
  .button::before { transition: none; }
  .button .button-label, .button .button-arrow { transition: none; transform: none !important; }
  .button .button-arrow-in { display: none; }
  .button .button-arrow-out { opacity: 1 !important; }
}

/* GSAP owns these properties only when motion is allowed and the library loaded.
   The rules above remain the no-library and reduced-motion fallback. */
.gsap-motion .button::before {
  transform: translate(-50%, -50%) scale(var(--motion-fill, 0));
  transition: none;
}
.gsap-motion .button-label,
.gsap-motion .button-arrow { transition: none; }
.gsap-motion .site-nav.is-open { animation: none; }