/*
 * Motion layer.
 *
 * The brand is calm and editorial, so the vocabulary is restrained: short
 * distances, soft easing, nothing that bounces. Everything animates transform
 * and opacity only, so it stays on the compositor and never costs layout.
 *
 * Every rule here is switched off under prefers-reduced-motion at the bottom
 * of the file.
 */

:root {
  --ease-out: cubic-bezier(0.22, 1, 0.36, 1);
  --ease-in-out: cubic-bezier(0.65, 0, 0.35, 1);
  --dur-fast: 160ms;
  --dur: 280ms;
  --dur-slow: 560ms;
}

html {
  scroll-behavior: smooth;
}

/* ------------------------------------------------------ entrance reveals */

/*
 * reveal.js adds `.reveal` at runtime, so with JavaScript disabled nothing is
 * ever hidden. `--i` staggers siblings.
 */
.reveal {
  opacity: 0;
  transform: translateY(22px);
  transition:
    opacity var(--dur-slow) var(--ease-out),
    transform var(--dur-slow) var(--ease-out);
  transition-delay: calc(var(--i, 0) * 80ms);
  will-change: opacity, transform;
}
.reveal.is-visible {
  opacity: 1;
  transform: none;
  will-change: auto;
}

/* The cover arrives from slightly further out, with a touch of rotation. */
.book-art.reveal {
  transform: translateY(30px) scale(0.97) rotate(-1.2deg);
}
.book-art.reveal.is-visible {
  transform: none;
}

/* ---------------------------------------------------------------- header */

.topbar a {
  animation: title-settle 1100ms var(--ease-out) both;
}
@keyframes title-settle {
  from {
    opacity: 0;
    letter-spacing: 0.34em;
  }
  to {
    opacity: 1;
  }
}

.nav a {
  position: relative;
}
/* A rule that grows from the centre on hover. */
.nav a:not(.is-cta):not(.is-muted)::after {
  content: '';
  position: absolute;
  inset-inline: 13px;
  bottom: 3px;
  height: 1px;
  background: currentColor;
  transform: scaleX(0);
  transform-origin: center;
  transition: transform var(--dur) var(--ease-out);
  opacity: 0.55;
}
.nav a:not(.is-cta):not(.is-muted):hover::after,
.nav a:not(.is-cta):not(.is-muted):focus-visible::after {
  transform: scaleX(1);
}
.nav a.is-cta {
  transition:
    transform var(--dur-fast) var(--ease-out),
    box-shadow var(--dur) var(--ease-out);
}
.nav a.is-cta:hover {
  transform: translateY(-1px);
  box-shadow: 0 6px 16px rgba(43, 39, 36, 0.28);
}
.nav-inner {
  transition: max-height var(--dur) var(--ease-in-out);
}

/* --------------------------------------------------------------- buttons */

/*
 * The sheen is a background layer rather than a pseudo-element: a pseudo-element
 * paints above the label (or, with a negative z-index, disappears behind the
 * button's own background), whereas a background-image always sits under the
 * text exactly where it belongs.
 */
.btn {
  position: relative;
  background-image: linear-gradient(
    115deg,
    transparent 38%,
    rgba(255, 255, 255, 0.26) 50%,
    transparent 62%
  );
  background-repeat: no-repeat;
  background-size: 260% 100%;
  background-position: 170% 0;
  transition:
    transform var(--dur-fast) var(--ease-out),
    box-shadow var(--dur) var(--ease-out),
    opacity var(--dur-fast) var(--ease-out),
    background-color var(--dur) var(--ease-out),
    background-position 720ms cubic-bezier(0.45, 0, 0.25, 1),
    color var(--dur) var(--ease-out),
    border-color var(--dur) var(--ease-out);
}
.btn:hover,
.btn:focus-visible {
  background-position: -70% 0;
}
.btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 10px 22px rgba(43, 39, 36, 0.26);
}
.btn:active {
  transform: translateY(0) scale(0.985);
  box-shadow: 0 3px 8px rgba(43, 39, 36, 0.22);
}
.btn[aria-disabled='true'],
.btn[disabled] {
  transform: none !important;
  box-shadow: none !important;
  background-position: 170% 0 !important;
}

/* The ghost button fills in on hover, so the same light sheen reads on it. */
.btn-ghost:hover {
  background-color: var(--btn);
  color: #fff;
  border-color: var(--btn);
}

/* ----------------------------------------------------------------- cover */

.book-art img,
.book-placeholder {
  transition:
    transform var(--dur-slow) var(--ease-out),
    filter var(--dur-slow) var(--ease-out),
    box-shadow var(--dur-slow) var(--ease-out);
}
.book-row:hover .book-art img {
  transform: translateY(-10px) rotate(-1deg);
  filter: drop-shadow(22px 30px 44px rgba(43, 39, 36, 0.32));
}
.book-row:hover .book-placeholder {
  transform: translateY(-10px) rotate(-1deg);
  box-shadow: 20px 28px 42px rgba(43, 39, 36, 0.36);
}

/* ----------------------------------------------------------------- cards */

.panel,
.stat {
  transition:
    transform var(--dur) var(--ease-out),
    box-shadow var(--dur) var(--ease-out),
    border-color var(--dur) var(--ease-out);
}
/* Only cards that lead somewhere lift on hover. */
.panel:has(a[href]):hover,
.stat:hover {
  transform: translateY(-3px);
  box-shadow: 0 12px 28px rgba(43, 39, 36, 0.1);
  border-color: rgba(43, 39, 36, 0.22);
}

.grid article.panel img {
  transition: transform var(--dur-slow) var(--ease-out);
}
.grid article.panel:hover img {
  transform: scale(1.035);
}

.book-badge,
.pill {
  transition:
    transform var(--dur-fast) var(--ease-out),
    background-color var(--dur) var(--ease-out);
}
.book-badge:hover {
  transform: translateY(-1px);
}

/* ----------------------------------------------------------------- forms */

input[type='text'],
input[type='email'],
input[type='tel'],
input[type='number'],
input[type='password'],
textarea,
select {
  transition:
    border-color var(--dur) var(--ease-out),
    box-shadow var(--dur) var(--ease-out),
    background-color var(--dur) var(--ease-out);
}
input:focus,
textarea:focus,
select:focus {
  border-color: var(--btn);
  box-shadow: 0 0 0 3px rgba(60, 60, 58, 0.1);
}

label {
  transition: color var(--dur) var(--ease-out);
}
.field:focus-within label {
  color: var(--ink);
}

/* ---------------------------------------------------------------- notices */

.note {
  animation: note-in var(--dur-slow) var(--ease-out) both;
}
@keyframes note-in {
  from {
    opacity: 0;
    transform: translateY(-8px);
  }
}

/* ----------------------------------------------------------------- tables */

tbody tr {
  transition: background-color var(--dur-fast) var(--ease-out);
}

/* ------------------------------------------------------------------ links */

a:not(.btn):not(.nav a) {
  transition: color var(--dur-fast) var(--ease-out), opacity var(--dur-fast) var(--ease-out);
}
.footer a {
  transition: opacity var(--dur-fast) var(--ease-out);
}
.footer a:hover {
  opacity: 0.72;
}

/* --------------------------------------------------------- reduced motion */

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
  *,
  *::before,
  *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
    scroll-behavior: auto !important;
  }
  .reveal,
  .book-art.reveal {
    opacity: 1;
    transform: none;
  }
}