@import url("tokens.css");

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

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

html {
  scroll-padding-top: calc(var(--nav-height) + var(--space-sm));
  background-color: var(--color-paper);
}

html,
body {
  margin: 0;
  overflow-x: clip;
}

body {
  position: relative;
  font-family: var(--font-body);
  font-size: var(--text-base);
  line-height: 1.75;
  color: var(--color-ink);
  background-color: transparent;
  touch-action: manipulation;
  -webkit-tap-highlight-color: oklch(68% 0.18 45 / 0.15);
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: -1;
  background-image:
    var(--paper-noise),
    url("../assets/decorative/paper-texture.png");
  background-size: 512px 512px, cover;
  background-repeat: repeat, no-repeat;
  background-position: center;
  opacity: 0.72;
  mix-blend-mode: multiply;
  pointer-events: none;
}

img {
  display: block;
  max-width: 100%;
  height: auto;
}

a {
  color: var(--color-paper-accent-deep);
  text-underline-offset: 0.2em;
}

a:hover {
  color: var(--color-paper-accent);
}

a:focus-visible {
  outline: 2px solid var(--color-focus);
  outline-offset: 3px;
}

.skip-link {
  position: absolute;
  top: var(--space-sm);
  left: var(--space-sm);
  z-index: 1000;
  padding: var(--space-sm) var(--space-md);
  background: var(--color-paper);
  color: var(--color-ink);
  text-decoration: none;
  transform: translateY(-200%);
  transition: transform var(--dur-fast) var(--ease-out);
}

.skip-link:focus-visible {
  transform: translateY(0);
}

/* ── Nav ── */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  height: var(--nav-height);
  background: var(--color-nav-bg);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--color-rule);
}

.site-nav {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-md);
  max-width: var(--max-content);
  height: 100%;
  margin: 0 auto;
  padding: 0 var(--space-page-inline);
}

.site-nav--centered .site-nav__panel {
  justify-content: center;
}

.site-nav__toggle {
  display: none;
  align-items: center;
  justify-content: center;
  width: 2.75rem;
  height: 2.75rem;
  padding: 0;
  border: 1px solid var(--color-rule);
  border-radius: var(--radius-sm);
  background: var(--color-paper);
  color: var(--color-ink);
  cursor: pointer;
}

.site-nav__toggle-icon {
  position: relative;
  display: block;
  width: 1.25rem;
  height: 0.875rem;
}

.site-nav__toggle-bar {
  position: absolute;
  left: 0;
  width: 100%;
  height: 2px;
  border-radius: 1px;
  background: currentColor;
  transition:
    transform var(--dur-base) var(--ease-out),
    opacity var(--dur-fast) var(--ease-out),
    top var(--dur-base) var(--ease-out);
}

.site-nav__toggle-bar:nth-child(1) {
  top: 0;
}

.site-nav__toggle-bar:nth-child(2) {
  top: 50%;
  transform: translateY(-50%);
}

.site-nav__toggle-bar:nth-child(3) {
  top: 100%;
  transform: translateY(-100%);
}

.site-nav__toggle[aria-expanded="true"] .site-nav__toggle-bar:nth-child(1) {
  top: 50%;
  transform: translateY(-50%) rotate(45deg);
}

.site-nav__toggle[aria-expanded="true"] .site-nav__toggle-bar:nth-child(2) {
  opacity: 0;
}

.site-nav__toggle[aria-expanded="true"] .site-nav__toggle-bar:nth-child(3) {
  top: 50%;
  transform: translateY(-50%) rotate(-45deg);
}

.site-nav__toggle:hover {
  border-color: var(--color-paper-accent);
  color: var(--color-paper-accent-deep);
}

.site-nav__toggle:focus-visible {
  outline: 2px solid var(--color-focus);
  outline-offset: 3px;
}

.site-nav__panel {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  flex-wrap: wrap;
  justify-content: flex-end;
}

.site-nav__link {
  padding: var(--space-xs) var(--space-sm);
  color: var(--color-ink-muted);
  text-decoration: none;
  font-size: var(--text-sm);
  white-space: nowrap;
  border-bottom: 2px solid transparent;
  transition: color var(--dur-fast) var(--ease-out), border-color var(--dur-fast) var(--ease-out);
}

.site-nav__link:hover,
.site-nav__link.is-active {
  color: var(--color-ink);
  border-bottom-color: var(--color-paper-accent);
}

/* ── Hero ── */
.hero {
  position: relative;
  overflow: hidden;
  background-color: var(--color-paper-accent);
}

.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image: url("../assets/decorative/shippo-pattern.png");
  background-repeat: repeat;
  background-size: var(--shippo-tile-width) auto;
  opacity: 0.28;
  mix-blend-mode: multiply;
  pointer-events: none;
}

.hero__inner {
  position: relative;
  z-index: 1;
  max-width: var(--max-content);
  margin: 0 auto;
  padding: var(--space-3xl) var(--space-page-inline) var(--space-4xl);
}

.hero__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  gap: var(--space-2xl) var(--space-3xl);
  align-items: center;
}

.hero__text {
  min-width: 0;
}

.hero__eyebrow {
  margin: 0 0 var(--space-md);
  font-size: var(--text-base);
  letter-spacing: 0.14em;
  color: var(--color-on-accent);
  opacity: 0.92;
}

.hero__title {
  margin: 0;
  font-family: var(--font-display);
  font-size: var(--text-hero-title);
  font-weight: 700;
  font-style: normal;
  line-height: 1.35;
  letter-spacing: 0.02em;
  color: var(--color-display);
  overflow-wrap: anywhere;
  min-width: 0;
}

.hero__title-line {
  display: block;
}

.hero__title:focus {
  outline: none;
}

.hero__title:focus-visible {
  outline: 2px solid var(--color-on-accent);
  outline-offset: 4px;
}

.hero__subtitle {
  margin: var(--space-lg) 0 0;
  font-family: var(--font-display);
  font-size: var(--text-hero-sub);
  font-weight: 500;
  font-style: normal;
  line-height: 1.35;
  color: var(--color-on-accent);
}

.hero__visual {
  min-width: 0;
  justify-self: end;
  width: 100%;
  max-width: 26rem;
}

.hero__poster-wrap {
  padding: var(--space-md);
  background:
    linear-gradient(var(--color-paper) 1px, transparent 1px),
    linear-gradient(90deg, var(--color-paper) 1px, transparent 1px),
    var(--color-paper);
  background-size: 20px 20px;
  box-shadow: 0 12px 32px oklch(0% 0 0 / 0.18);
  transform: rotate(1deg);
}

.hero__poster-wrap img {
  width: 100%;
}

.hero__meta {
  margin-top: var(--space-xl);
  color: var(--color-on-accent);
}

.hero__schedule {
  margin-bottom: var(--space-md);
}

.hero__dates-label {
  margin: 0 0 var(--space-xs);
  font-size: var(--text-sm);
  font-weight: 600;
  letter-spacing: 0.08em;
  opacity: 0.85;
}

.hero__dates {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: var(--space-sm);
  margin: 0;
  font-family: var(--font-display);
  font-size: var(--text-hero-meta);
  font-weight: 500;
  line-height: 1.3;
}

.hero__dates-sep {
  opacity: 0.7;
}

.hero__location {
  margin: 0;
  font-size: var(--text-lg);
  line-height: 1.65;
  max-width: 32ch;
}

/* ── About decorative strip ── */
#about .section__inner--narrow {
  position: relative;
}

.about-deco {
  position: relative;
  height: 5rem;
  margin-bottom: var(--space-xl);
}

.about-deco__item {
  position: absolute;
  opacity: 0.75;
  filter: drop-shadow(0 2px 8px oklch(0% 0 0 / 0.08));
}

.about-deco__item--koinobori {
  top: 0;
  left: 0;
  width: 4.5rem;
}

.about-deco__item--kimono {
  top: -0.5rem;
  right: 15%;
  width: 3.5rem;
}

.about-deco__item--inu {
  bottom: 0;
  right: 0;
  width: 3.25rem;
}

.about-deco__item--lily {
  bottom: 0.25rem;
  left: 38%;
  width: 2.5rem;
}

/* 章節區塊左右留白：padding 的左右值來自 --space-page-inline（tokens.css） */
.section {
  padding: var(--space-3xl) var(--space-page-inline);
}

.section__inner {
  max-width: var(--max-content);
  margin: 0 auto;
}

.section__inner--narrow {
  max-width: var(--max-prose);
}

.section__heading {
  margin: 0 0 var(--space-xl);
  font-family: var(--font-display);
  font-size: var(--text-2xl);
  font-weight: 700;
  font-style: normal;
  line-height: 1.3;
  overflow-wrap: anywhere;
  min-width: 0;
  text-wrap: balance;
}

/* ── Chapter layout ── */
.chapter {
  display: grid;
  grid-template-columns: minmax(0, 6rem) minmax(0, 1fr);
  gap: var(--space-lg) var(--space-xl);
  align-items: start;
}

.chapter__index {
  font-family: var(--font-display);
  font-size: var(--text-display);
  font-weight: 700;
  font-style: normal;
  line-height: 1;
  color: var(--color-paper-accent);
  opacity: 0.35;
}

.chapter__body {
  min-width: 0;
}

.chapter__title {
  margin: 0 0 var(--space-lg);
  font-family: var(--font-display);
  font-size: var(--text-xl);
  font-weight: 700;
  font-style: normal;
  overflow-wrap: anywhere;
  text-wrap: balance;
}

.chapter__body p {
  margin: 0 0 var(--space-md);
  text-align: justify;
}

.chapter__body p:last-child {
  margin-bottom: 0;
}

.chapter__note {
  display: flex;
  flex-direction: row;
  align-items: flex-start;
  gap: 0.35em;
  margin-top: calc(-1 * var(--space-xs));
  font-size: var(--text-xs);
  line-height: 1.6;
  color: var(--color-caption);
  text-align: left;
}

.chapter__note-mark {
  font-size: 0.55em;
  font-weight: 500;
  line-height: 0;
  vertical-align: super;
}

.chapter__note-mark a {
  color: var(--color-caption);
  text-decoration: none;
}

.chapter__note-mark a:hover,
.chapter__note-mark a:focus-visible {
  color: var(--color-ink);
  text-decoration: underline;
}

.chapter__note-index {
  flex-shrink: 0;
  font-size: 0.75em;
  font-weight: 600;
  line-height: 1.6;
}

.chapter__note-text {
  flex: 1;
  min-width: 0;
}

.chapter__note a {
  color: inherit;
  word-break: break-all;
}

.chapter__note a:hover {
  color: var(--color-ink);
}

/* ── Letters & 繪本摘錄 ── */
.letter-block {
  margin: var(--space-xl) 0;
  padding: var(--space-lg);
  background: var(--color-paper);
  border: 1px solid var(--color-rule);
  box-shadow: 0 2px 8px oklch(0% 0 0 / 0.04);
}

.letter-block__meta {
  margin: 0 0 var(--space-sm);
  font-size: var(--text-sm);
  color: var(--color-caption);
}

.letter-block__label {
  margin: 0 0 var(--space-md);
  font-size: var(--text-base);
  font-weight: 700;
}

.letter-block__poem,
.letter-block__ja {
  margin: 0 0 var(--space-md);
  font-size: var(--text-base);
  line-height: 1.9;
}

.letter-block__poem {
  font-family: var(--font-display);
  white-space: pre-line;
  padding-left: 3em;
}

.letter-block__ja {
  padding: 0;
  border: none;
  font-family: var(--font-body);
  color: var(--color-ink);
}

.letter-block__zh + .letter-block__ja {
  margin-top: var(--space-2xl);
}

.letter-block__prose,
.letter-block__zh {
  margin: 0;
  padding-top: var(--space-md);
  border-top: 1px solid var(--color-rule);
  font-size: var(--text-base);
  line-height: 1.75;
  color: var(--color-ink-muted);
}

.letter-block__prose {
  white-space: pre-line;
}

/* ── Gallery ── */
.gallery {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(min(100%, 11rem), var(--artifact-thumb-max)));
  justify-content: center;
  gap: var(--space-lg);
  margin-block: var(--space-xl);
  padding: 0;
  list-style: none;
}

.gallery__item {
  min-width: 0;
}

.artifact-figure {
  margin: 0;
}

#chapter-1 .chapter__body > .artifact-figure,
#chapter-3 .chapter__body > .artifact-figure {
  width: fit-content;
  max-width: min(100%, var(--artifact-inline-max));
  margin: var(--space-xl) auto;
  text-align: center;
}

.artifact-figure__link {
  display: block;
  padding: var(--space-sm);
  background:
    linear-gradient(var(--color-rule) 1px, transparent 1px),
    linear-gradient(90deg, var(--color-rule) 1px, transparent 1px),
    var(--color-paper);
  background-size: 16px 16px;
  text-decoration: none;
  cursor: zoom-in;
  transition: transform var(--dur-base) var(--ease-out), box-shadow var(--dur-base) var(--ease-out);
}

.artifact-figure__link:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 16px oklch(0% 0 0 / 0.1);
}

.artifact-figure__link:active {
  transform: translateY(0);
  box-shadow: 0 2px 8px oklch(0% 0 0 / 0.08);
}

.artifact-figure__link:focus-visible {
  outline: 2px solid var(--color-focus);
  outline-offset: 2px;
}

.artifact-figure img {
  width: 100%;
  aspect-ratio: 4 / 3;
  object-fit: contain;
  background: var(--color-paper);
}

#chapter-1 .chapter__body > .artifact-figure img,
#chapter-3 .chapter__body > .artifact-figure img {
  width: auto;
  max-width: 100%;
  max-height: min(50vh, 24rem);
  height: auto;
  aspect-ratio: auto;
  margin-inline: auto;
}

.artifact-figure figcaption {
  margin-top: var(--space-sm);
  font-size: var(--text-xs);
  line-height: 1.5;
  color: var(--color-caption);
  text-align: center;
}

/* ── Visit ── */
.section--visit {
  position: relative;
  background-color: var(--color-visit-bg);
  border-block: 1px solid var(--color-visit-border);
}

.section--visit::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image: url("../assets/decorative/shippo-pattern.png");
  background-repeat: repeat;
  background-size: var(--shippo-tile-width) auto;
  opacity: 0.07;
  filter: invert(1) sepia(0.15) hue-rotate(10deg);
  pointer-events: none;
}

.section--visit .section__inner {
  position: relative;
  z-index: 1;
}

.visit-lead {
  margin: 0 0 var(--space-2xl);
  padding-bottom: var(--space-lg);
  border-bottom: 1px solid var(--color-visit-border);
  font-size: var(--text-lg);
  line-height: 1.6;
  color: var(--color-ink);
}

.visit-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  gap: var(--space-xl);
  align-items: start;
}

.visit-panel {
  padding: var(--space-xl);
  background: var(--color-visit-panel);
  border: 1px solid var(--color-visit-border);
  box-shadow: var(--shadow-panel);
}

.visit-block {
  margin-bottom: var(--space-xl);
}

.visit-block:last-child {
  margin-bottom: 0;
}

.visit-block__title {
  margin: 0 0 var(--space-sm);
  font-family: var(--font-display);
  font-size: var(--text-lg);
  font-weight: 700;
  font-style: normal;
  color: var(--color-paper-accent-deep);
}

.visit-block p {
  margin: 0;
}

.visit-list {
  margin: 0;
  padding-left: 1.25rem;
}

.visit-list li {
  margin-bottom: var(--space-sm);
}

.visit-list li:last-child {
  margin-bottom: 0;
}

.visit-map {
  min-width: 0;
}

.visit-map__title {
  margin: 0 0 var(--space-md);
  font-family: var(--font-display);
  font-size: var(--text-lg);
  font-weight: 700;
  font-style: normal;
  color: var(--color-paper-accent-deep);
}

.visit-map__embed {
  overflow: hidden;
  border: 1px solid var(--color-visit-border);
  background: var(--color-visit-panel);
  box-shadow: var(--shadow-panel);
}

.visit-map__embed iframe {
  display: block;
  width: 100%;
  min-height: 20rem;
  border: 0;
  aspect-ratio: 4 / 3;
}

.visit-map__link {
  margin: var(--space-md) 0 0;
  font-size: var(--text-sm);
  text-align: center;
}

.visit-map__link a {
  overflow-wrap: anywhere;
}

/* ── Footer ── */
.site-footer {
  padding: var(--space-2xl) var(--space-page-inline);
  background: var(--color-ink);
  color: var(--color-footer-fg);
  text-align: center;
}

.site-footer p {
  margin: 0 0 var(--space-sm);
  font-size: var(--text-sm);
  line-height: 1.6;
}

.site-footer p:last-child {
  margin-bottom: 0;
}

.site-footer a {
  color: var(--color-footer-fg);
}

.site-footer a:hover {
  color: var(--color-display);
}

.site-footer a:focus-visible {
  outline: 2px solid var(--color-display);
  outline-offset: 3px;
}

/* ── Back to top ── */
.back-to-top {
  position: fixed;
  right: max(var(--space-page-inline), calc(var(--space-safe-inline) + 1.25rem));
  bottom: max(var(--space-md), env(safe-area-inset-bottom, 0px));
  z-index: 90;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 2.75rem;
  height: 2.75rem;
  padding: 0;
  border: 1px solid var(--color-rule);
  border-radius: var(--radius-sm);
  background: var(--color-paper);
  color: var(--color-ink);
  cursor: pointer;
  box-shadow: var(--shadow-elevated);
  opacity: 0;
  visibility: hidden;
  transform: translateY(0.5rem);
  transition:
    opacity var(--dur-base) var(--ease-out),
    visibility var(--dur-base) var(--ease-out),
    transform var(--dur-base) var(--ease-out),
    background var(--dur-fast) var(--ease-out),
    color var(--dur-fast) var(--ease-out),
    border-color var(--dur-fast) var(--ease-out);
}

.back-to-top.is-visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.back-to-top:hover {
  background: var(--color-paper-accent);
  color: var(--color-on-accent);
  border-color: var(--color-paper-accent);
}

.back-to-top:active {
  transform: translateY(1px);
}

.back-to-top.is-visible:active {
  transform: translateY(1px);
}

.back-to-top:focus-visible {
  outline: 2px solid var(--color-focus);
  outline-offset: 3px;
}

.back-to-top__icon {
  display: block;
  width: 1.25rem;
  height: 1.25rem;
}

/* ── Lightbox ── */
.is-lightbox-open {
  overflow: hidden;
  overscroll-behavior: contain;
}

.lightbox[hidden] {
  display: none;
}

.lightbox {
  position: fixed;
  inset: 0;
  z-index: 200;
  display: grid;
  place-items: center;
  padding: var(--space-md);
}

.lightbox__backdrop {
  position: absolute;
  inset: 0;
  background: var(--color-overlay);
}

.lightbox__panel {
  position: relative;
  z-index: 1;
  width: min(100%, 56rem);
  max-height: 90vh;
  overflow: auto;
  overscroll-behavior: contain;
  padding: var(--space-lg);
  background: var(--color-paper);
  border-radius: var(--radius-md);
}

.lightbox__close {
  position: absolute;
  top: var(--space-sm);
  right: var(--space-sm);
  width: 2.75rem;
  height: 2.75rem;
  border: none;
  border-radius: var(--radius-sm);
  background: var(--color-paper-accent);
  color: var(--color-on-accent);
  font-size: 1.5rem;
  line-height: 1;
  cursor: pointer;
}

.lightbox__close:hover {
  background: var(--color-paper-accent-deep);
}

.lightbox__close:active {
  transform: scale(0.96);
}

.lightbox__close:focus-visible {
  outline: 2px solid var(--color-focus);
  outline-offset: 2px;
}

.lightbox__img {
  width: 100%;
  max-height: 70vh;
  object-fit: contain;
  margin: 0 auto;
  opacity: 0;
  transition: opacity var(--dur-fast) var(--ease-out);
}

.lightbox__img.is-loaded {
  opacity: 1;
}

.lightbox__caption {
  margin-top: var(--space-md);
  font-size: var(--text-sm);
  color: var(--color-caption);
  text-align: center;
}

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

/* ── Reveal ── */
.reveal {
  opacity: 0;
  transform: translateY(1rem);
  transition: opacity var(--dur-slow) var(--ease-out), transform var(--dur-slow) var(--ease-out);
}

.reveal.is-visible {
  opacity: 1;
  transform: translateY(0);
}

@media (prefers-reduced-motion: reduce) {
  .reveal {
    opacity: 1;
    transform: none;
    transition: none;
  }

  .artifact-figure__link:hover {
    transform: none;
  }

  .artifact-figure__link:active {
    transform: none;
  }

  .back-to-top {
    transition: none;
    transform: none;
  }

  .back-to-top.is-visible:active {
    transform: none;
  }

  .lightbox__close:active {
    transform: none;
  }

  .lightbox__img {
    opacity: 1;
    transition: none;
  }

  .hero__poster-wrap {
    transform: none;
  }

  .site-nav__toggle-bar {
    transition: none;
  }
}

/* ── Responsive ── */
@media (max-width: 768px) {
  :root {
    --space-page-inline: max(2.5rem, calc(1.25rem + var(--space-safe-inline)));
  }

  .site-nav {
    justify-content: flex-end;
  }

  .site-nav__toggle {
    display: flex;
    margin-left: auto;
  }

  .site-nav__panel {
    display: none;
    position: absolute;
    top: var(--nav-height);
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: stretch;
    padding: var(--space-md);
    background: var(--color-nav-bg);
    border-bottom: 1px solid var(--color-rule);
    backdrop-filter: blur(8px);
  }

  .site-nav__panel.is-open {
    display: flex;
  }

  .site-nav__link {
    padding: var(--space-sm);
    white-space: nowrap;
  }

  .chapter {
    grid-template-columns: minmax(0, 1fr);
    gap: var(--space-sm);
  }

  .chapter__index {
    font-size: var(--text-2xl);
  }

  .hero__grid {
    grid-template-columns: minmax(0, 1fr);
    gap: var(--space-xl);
  }

  .hero__visual {
    justify-self: center;
    max-width: 20rem;
  }

  .hero__poster-wrap {
    transform: none;
  }

  .hero__inner {
    padding-top: var(--space-2xl);
    padding-bottom: var(--space-3xl);
  }

  .visit-layout {
    grid-template-columns: minmax(0, 1fr);
  }

  .back-to-top {
    right: max(var(--space-md), env(safe-area-inset-right, 0px));
  }

  .about-deco {
    height: 3.5rem;
    margin-bottom: var(--space-lg);
  }

  .about-deco__item--koinobori {
    width: 3.15rem;
  }

  .about-deco__item--kimono {
    top: -0.35rem;
    right: 15%;
    width: 2.45rem;
  }

  .about-deco__item--inu {
    width: 2.275rem;
  }

  .about-deco__item--lily {
    bottom: 0.175rem;
    left: 38%;
    width: 1.75rem;
  }
}

@media (max-width: 375px) {
  .hero__title {
    font-size: clamp(1.75rem, 4.5vw + 0.9rem, 2.35rem);
    line-height: 1.4;
  }
}