/* =========================================================================
   地熱シンポジウム in 福岡 ｜ ティザーサイト
   style.css

   アクセシビリティ方針:
   - 文字色はすべて背景に対してWCAG 2.1 / JIS X 8341-3 レベルAA基準
     (通常文字4.5:1以上、大きな文字3:1以上)のコントラスト比を満たすよう調整。
     Figmaデザイン上の最も薄いグレー(#aeada8)は本文サイズでは基準を満たさない
     ため、判読が必要なテキストには secondary(#6b6b68) を使用し、
     tertiary(#8a8a86)は装飾目的かつ大きな文字にのみ使用しています。
   - フォーカスインジケータを明示。
   - prefers-reduced-motion に対応。
   ========================================================================= */

:root {
  /* --- カラートークン --- */
  --color-bg: #f9f9f7;
  --color-bg-white: #ffffff;
  --color-bg-dark: #1c1c1a;
  --color-border: #ddddd9;
  --color-border-dark: rgba(255, 255, 255, 0.14);

  --color-text-primary: #1c1c1a;      /* 本文・見出し: コントラスト比 約18:1 */
  --color-text-secondary: #6b6b68;    /* 補足文・ラベル: 約5.1:1 (AA適合) */
  --color-text-tertiary: #8a8a86;     /* 装飾的な大きな文字専用: 約3.3:1 (大文字AA適合) */
  --color-text-watermark: rgba(28, 28, 26, 0.06); /* 完全装飾。aria-hidden必須 */

  --color-accent: #3f6d92;            /* ステータスチップ文字: 約5.2:1 (AA適合) */
  --color-accent-border: rgba(63, 109, 146, 0.55);
  --color-accent-vermillion: #C64B2E;
  --color-text-watermark-accent: rgba(198, 75, 46, 0.08);

  --color-footer-text: #ffffff;
  --color-footer-text-secondary: rgba(255, 255, 255, 0.72); /* 約9:1 */
  --color-footer-text-muted: rgba(255, 255, 255, 0.55);     /* 約6:1 */

  --font-jp: "Noto Sans JP", "Hiragino Sans", "Yu Gothic", sans-serif;
  --font-condensed: "Barlow Condensed", var(--font-jp);
  --font-mono: "DM Mono", "Noto Sans JP", monospace;

  --container-max: 1024px;
  --focus-ring: 3px solid #3f6d92;
}

/* --- リセット / ベース --- */
*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
  scroll-behavior: smooth;
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
}

body {
  margin: 0;
  font-family: var(--font-jp);
  color: var(--color-text-primary);
  background: var(--color-bg);
  line-height: 1.7;
  font-feature-settings: "palt" 1;
}

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

a {
  color: inherit;
}

h1,
h2,
h3,
p,
dl,
dd {
  margin: 0;
}

ul {
  list-style: none;
  margin: 0;
  padding: 0;
}

/* --- フォーカス可視化 (WCAG 2.4.7 / JIS AA) --- */
a:focus-visible,
button:focus-visible {
  outline: var(--focus-ring);
  outline-offset: 3px;
  border-radius: 2px;
}

/* --- スキップリンク (WCAG 2.4.1) --- */
.skip-link {
  position: absolute;
  left: 0;
  top: 0;
  transform: translateY(-120%);
  background: var(--color-text-primary);
  color: #fff;
  padding: 12px 20px;
  font-size: 14px;
  font-weight: 600;
  z-index: 10000;
  transition: transform 0.15s ease;
  text-decoration: none;
}

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

/* --- 視覚的に隠すが支援技術には読み上げさせる --- */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

hr.rule {
  border: none;
  border-top: 1px solid var(--color-border);
  margin: 16px 0;
  width: 100%;
}

/* =========================================================================
   ローディング演出 (湯煙イントロ)

   アクセシビリティ方針:
   - 実際のページ内容の複製に過ぎない装飾のため aria-hidden で
     支援技術からは完全に除外する。フォーカス可能な要素は含まない。
   - prefers-reduced-motion: reduce の場合はアニメーションを行わず、
     即座に非表示にする。
   - JSが実行されない環境でもCSSのアニメーションだけで自動的に消え、
     以降の本文操作を一切妨げない (pointer-events: none)。
   ========================================================================= */
.intro {
  position: fixed;
  inset: 0;
  z-index: 9998;
  overflow: hidden;
  background: var(--color-bg-dark);
  pointer-events: none;
  animation: intro-overlay-out 5.2s ease-in forwards;
}

/* 湯気が画面を満たして一瞬白く染まる、フェードアウト直前のフラッシュ */
.intro__flash {
  position: absolute;
  inset: 0;
  z-index: 4;
  background: #ffffff;
  opacity: 0;
  animation: intro-flash 5.2s ease-in-out forwards;
}

.intro__steam {
  position: absolute;
  inset: 0;
  overflow: hidden;
}

.intro__steam span {
  position: absolute;
  bottom: -22vh;
  transform: translateX(-50%);
  border-radius: 50%;
  background: radial-gradient(ellipse 50% 55% at 50% 65%, rgba(255, 255, 255, 1) 0%, rgba(255, 255, 255, 0.5) 40%, rgba(255, 255, 255, 0) 76%);
  opacity: 0;
  mix-blend-mode: screen;
  will-change: translate, scale, opacity;
}

/* 奥の層: 広く・薄くぼかし、山なりのシルエットの土台を作る */
.intro__steam--back {
  z-index: 1;
  animation: intro-layer-in 1.8s ease-out both;
}

.intro__steam--back span {
  width: 28vw;
  height: 46vh;
  min-width: 240px;
  min-height: 320px;
  max-width: 400px;
  max-height: 460px;
  filter: blur(48px);
}

.intro__steam--back span:nth-child(1) { left: 2%;  height: 48vh; animation: mist-drift-a 10s ease-in-out 0s infinite alternate; }
.intro__steam--back span:nth-child(2) { left: 20%; width: 32vw; height: 64vh; animation: mist-drift-b 12s ease-in-out 1.1s infinite alternate; }
.intro__steam--back span:nth-child(3) { left: 40%; height: 72vh; animation: mist-drift-a 11s ease-in-out 0.5s infinite alternate; }
.intro__steam--back span:nth-child(4) { left: 60%; width: 32vw; height: 62vh; animation: mist-drift-b 9.5s ease-in-out 1.6s infinite alternate; }
.intro__steam--back span:nth-child(5) { left: 80%; height: 46vh; animation: mist-drift-a 10.5s ease-in-out 0.8s infinite alternate; }
.intro__steam--back span:nth-child(6) { left: 10%; width: 26vw; height: 40vh; animation: mist-drift-b 9s ease-in-out 0.3s infinite alternate; }
.intro__steam--back span:nth-child(7) { left: 70%; width: 26vw; height: 40vh; animation: mist-drift-b 10.5s ease-in-out 1.4s infinite alternate; }

/* 土台の層: 画面下端に沿った明るく輪郭のはっきりめの帯で、
   大きなブロブが横一直線に集まっているように見せる */
.intro__mist-base {
  position: absolute;
  left: -4%;
  right: -4%;
  bottom: -10vh;
  height: 26vh;
  border-radius: 50%;
  background: radial-gradient(ellipse 55% 60% at 50% 70%, rgba(255, 255, 255, 1) 0%, rgba(255, 255, 255, 0.55) 45%, rgba(255, 255, 255, 0) 78%);
  filter: blur(30px);
  opacity: 0;
  mix-blend-mode: screen;
  animation: mist-drift-base 8s ease-in-out 0s infinite alternate;
  will-change: transform, opacity;
}

/* 立ち昇る層: 下から上へゆっくり昇っていくもくもくとした湯気。
   幅180px以上で複数サイズを用意し、無限ループでずらして発生させる */
.intro__steam--rise {
  z-index: 1;
  animation: intro-layer-in 1.4s ease-out both;
}

.intro__steam--rise span {
  position: absolute;
  left: 50%;
  bottom: -12vh;
  transform: translateX(-50%);
  border-radius: 50%;
  background: radial-gradient(ellipse 55% 55% at 50% 55%, rgba(255, 255, 255, 0.7) 0%, rgba(255, 255, 255, 0.26) 42%, rgba(255, 255, 255, 0) 76%);
  filter: blur(80px);
  opacity: 0;
  mix-blend-mode: screen;
  will-change: translate, scale, opacity;
}

.intro__steam--rise span:nth-child(1)  { left: 8%;  width: 610px;  height: 670px;  animation: steam-rise-loop 5.5s ease-in-out 0s infinite; }
.intro__steam--rise span:nth-child(2)  { left: 24%; width: 960px;  height: 1020px; animation: steam-rise-loop 7s ease-in-out 1.2s infinite; }
.intro__steam--rise span:nth-child(3)  { left: 40%; width: 700px;  height: 760px;  animation: steam-rise-loop 6s ease-in-out 0.4s infinite; }
.intro__steam--rise span:nth-child(4)  { left: 58%; width: 1090px; height: 1150px; animation: steam-rise-loop 7.5s ease-in-out 2.4s infinite; }
.intro__steam--rise span:nth-child(5)  { left: 76%; width: 670px;  height: 730px;  animation: steam-rise-loop 5.8s ease-in-out 1.6s infinite; }
.intro__steam--rise span:nth-child(6)  { left: 92%; width: 830px;  height: 890px;  animation: steam-rise-loop 6.6s ease-in-out 0.8s infinite; }
.intro__steam--rise span:nth-child(7)  { left: 0%;  width: 520px;  height: 580px;  animation: steam-rise-loop 6.2s ease-in-out 1.9s infinite; }
.intro__steam--rise span:nth-child(8)  { left: 16%; width: 880px;  height: 940px;  animation: steam-rise-loop 7.8s ease-in-out 0.6s infinite; }
.intro__steam--rise span:nth-child(9)  { left: 32%; width: 640px;  height: 700px;  animation: steam-rise-loop 5.2s ease-in-out 2.6s infinite; }
.intro__steam--rise span:nth-child(10) { left: 48%; width: 980px;  height: 1040px; animation: steam-rise-loop 6.8s ease-in-out 1.4s infinite; }
.intro__steam--rise span:nth-child(11) { left: 66%; width: 560px;  height: 620px;  animation: steam-rise-loop 7.2s ease-in-out 0.2s infinite; }
.intro__steam--rise span:nth-child(12) { left: 84%; width: 760px;  height: 820px;  animation: steam-rise-loop 6.4s ease-in-out 2s infinite; }

/* 手前の層: 一回り小さく、テキストのすぐ手前を漂わせる */
.intro__steam--front {
  z-index: 3;
  animation: intro-layer-in 2.2s ease-out 0.3s both;
}

.intro__steam--front span {
  width: 22vw;
  height: 34vh;
  min-width: 180px;
  min-height: 220px;
  max-width: 300px;
  max-height: 320px;
  filter: blur(36px);
}

.intro__steam--front span:nth-child(1) { left: 22%; animation: mist-drift-front 8s ease-in-out 0.2s infinite alternate; }
.intro__steam--front span:nth-child(2) { left: 46%; height: 38vh; animation: mist-drift-front 9s ease-in-out 1.3s infinite alternate; }
.intro__steam--front span:nth-child(3) { left: 66%; animation: mist-drift-front 7.5s ease-in-out 0.7s infinite alternate; }

.intro__text-group {
  position: absolute;
  z-index: 2;
  left: 50%;
  top: 42%;
  transform: translate(-50%, -50%);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 18px;
  width: 100%;
  padding: 0 20px;
}

.intro__text {
  margin: 0;
  color: var(--color-accent-vermillion);
  text-shadow: 0 0 10px rgba(255, 255, 255, 0.9), 0 0 22px rgba(255, 255, 255, 0.6),
    0 2px 6px rgba(255, 255, 255, 0.7);
  font-weight: 900;
  font-size: clamp(2.2rem, 8vw, 6rem);
  line-height: 1.25;
  text-align: center;
  opacity: 0;
  animation: intro-line-in 1s ease-out 0.5s forwards;
}

.intro__meta {
  margin: 0;
  color: var(--color-footer-text);
  font-family: var(--font-condensed);
  font-weight: 600;
  font-size: clamp(0.9rem, 2.4vw, 1.15rem);
  letter-spacing: 0.3em;
  text-transform: uppercase;
  text-shadow: 0 1px 4px rgba(0, 0, 0, 0.7);
  opacity: 0;
  animation: intro-line-in 1s ease-out 0.9s forwards;
}

@keyframes intro-layer-in {
  0% {
    opacity: 0;
  }
  100% {
    opacity: 1;
  }
}

@keyframes mist-drift-base {
  0% {
    transform: scale(1, 1);
    opacity: 0.5;
  }
  50% {
    transform: scale(1.05, 1.1);
    opacity: 0.64;
  }
  100% {
    transform: scale(0.97, 0.95);
    opacity: 0.44;
  }
}

@keyframes mist-drift-a {
  0% {
    translate: 0 0;
    scale: 1;
    opacity: 0.5;
  }
  50% {
    translate: -1.5vw -2.5vh;
    scale: 1.08;
    opacity: 0.68;
  }
  100% {
    translate: 1.5vw -1vh;
    scale: 0.95;
    opacity: 0.42;
  }
}

@keyframes mist-drift-b {
  0% {
    translate: 0 0;
    scale: 1;
    opacity: 0.36;
  }
  50% {
    translate: 2vw -1.5vh;
    scale: 0.93;
    opacity: 0.52;
  }
  100% {
    translate: -1.5vw -3vh;
    scale: 1.1;
    opacity: 0.32;
  }
}

@keyframes steam-rise-loop {
  0% {
    translate: 0 0;
    scale: 0.85;
    opacity: 0;
  }
  12% {
    opacity: 0.16;
  }
  50% {
    translate: -2vw -55vh;
    scale: 1.05;
    opacity: 0.14;
  }
  85% {
    opacity: 0.05;
  }
  100% {
    translate: 2vw -115vh;
    scale: 1.3;
    opacity: 0;
  }
}

@keyframes mist-drift-front {
  0% {
    translate: 0 0;
    scale: 1;
    opacity: 0.28;
  }
  50% {
    translate: -2vw -2vh;
    scale: 1.06;
    opacity: 0.42;
  }
  100% {
    translate: 2vw -0.5vh;
    scale: 0.92;
    opacity: 0.22;
  }
}

@keyframes intro-line-in {
  0% {
    opacity: 0;
    transform: translateY(14px);
  }
  100% {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes intro-overlay-out {
  0%,
  86% {
    opacity: 1;
    visibility: visible;
  }
  100% {
    opacity: 0;
    visibility: hidden;
  }
}

@keyframes intro-flash {
  0%,
  64% {
    opacity: 0;
  }
  80% {
    opacity: 1;
  }
  86% {
    opacity: 1;
  }
  100% {
    opacity: 1;
  }
}

html.intro-active {
  overflow: hidden;
}

@media (prefers-reduced-motion: reduce) {
  .intro {
    display: none;
  }

  .intro__steam--back,
  .intro__steam--rise,
  .intro__steam--front,
  .intro__steam span,
  .intro__mist-base,
  .intro__flash {
    animation: none;
  }
}

/* --- 共通パーツ --- */
.eyebrow {
  display: flex;
  align-items: center;
  gap: 12px;
  font-family: var(--font-condensed);
  font-weight: 600;
  font-size: 13px;
  letter-spacing: 0.35em;
  text-transform: uppercase;
  color: var(--color-text-secondary);
}

.eyebrow__rule {
  width: 32px;
  height: 1px;
  background: var(--color-border);
  flex: none;
}

.label-mono {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.25em;
  text-transform: uppercase;
  color: var(--color-text-secondary);
  margin: 0 0 6px;
}

.section {
  border-bottom: 1px solid var(--color-border);
  padding: 96px 24px;
}

.section--white {
  background: var(--color-bg-white);
}

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

.section__heading {
  font-weight: 900;
  font-size: clamp(2.25rem, 6vw, 4.5rem);
  line-height: 1.08;
  letter-spacing: -0.01em;
  margin-top: 48px;
}

/* --- フェードアップ演出 (JSで is-visible 付与。JS無効・reduced-motionでも内容は表示される) --- */
.fade-up {
  opacity: 1;
  transform: none;
}

@media (prefers-reduced-motion: no-preference) {
  .js-enabled .fade-up {
    opacity: 0;
    transform: translateY(24px);
    transition: opacity 0.7s ease, transform 0.7s ease;
  }

  .js-enabled .fade-up.is-visible {
    opacity: 1;
    transform: none;
  }
}

/* =========================================================================
   ヘッダー
   ========================================================================= */
.site-header {
  border-bottom: 1px solid var(--color-border);
  background: var(--color-bg);
}

.site-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 12px 24px;
  flex-wrap: wrap;
}

.site-header__title {
  font-size: 11px;
  letter-spacing: 0.05em;
  color: var(--color-text-secondary);
}

.site-header__title a {
  text-decoration: none;
}

.site-header__title a:hover,
.site-header__title a:focus-visible {
  text-decoration: underline;
  text-underline-offset: 3px;
}

.site-header__meta {
  display: flex;
  align-items: center;
  gap: 16px;
}

.site-header__entry {
  font-size: 11px;
  font-weight: 500;
  color: var(--color-text-primary);
}

.site-header__code {
  font-family: var(--font-condensed);
  font-size: 11px;
  letter-spacing: 0.25em;
  text-transform: uppercase;
  color: var(--color-text-secondary);
}

/* =========================================================================
   ヒーロー
   ========================================================================= */
.hero {
  border-bottom: 1px solid var(--color-border);
  padding: 40px 24px 0;
}

.hero__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 56px;
  max-width: 1400px;
  margin: 0 auto;
  padding-bottom: 40px;
}

.hero__main {
  display: flex;
  flex-direction: column;
  gap: 24px;
}

.hero__heading {
  font-weight: 900;
  font-size: clamp(2.8rem, 13vw, 13rem);
  line-height: 1.05;
  margin: 24px 0 0;
  color: var(--color-accent-vermillion);
}

.hero__lead {
  font-size: 16px;
  color: var(--color-text-secondary);
  line-height: 2;
  max-width: 24rem;
}

.hero__location {
  align-self: flex-end;
  display: flex;
  align-items: baseline;
  gap: 8px;
  margin-top: 24px;
}

.hero__location-prefix {
  font-family: var(--font-jp);
  font-weight: 900;
  font-size: clamp(1.5rem, 4vw, 3.2rem);
  color: var(--color-text-tertiary);
}

.hero__location-main {
  font-family: var(--font-jp);
  font-weight: 900;
  font-size: clamp(3rem, 12vw, 9.9rem);
  line-height: 1;
  letter-spacing: -0.03em;
  color: var(--color-text-primary);
}

.hero__info {
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  gap: 40px;
  border-top: 1px solid var(--color-border);
  padding-top: 32px;
}

.hero__date {
  font-family: var(--font-condensed);
  font-weight: 700;
  font-size: clamp(4.5rem, 12vw, 11rem);
  line-height: 1;
  color: var(--color-text-primary);
  margin: 12px 0 0;
}

.hero__date-day {
  font-family: var(--font-condensed);
  font-weight: 600;
  font-size: 14px;
  letter-spacing: 0.3em;
  color: var(--color-text-secondary);
  margin-top: 8px;
}

.hero__info-block {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.hero__venue-name {
  font-weight: 600;
  font-size: 16px;
  margin-top: 4px;
}

.hero__venue-en {
  font-family: var(--font-condensed);
  font-size: 11px;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--color-text-secondary);
  margin-top: 2px;
}

.hero__entry {
  font-weight: 700;
  font-size: 21.6px;
  margin-top: 8px;
}

.hero__scroll {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding-bottom: 24px;
}

.hero__scroll-label {
  font-family: var(--font-mono);
  font-size: 9px;
  letter-spacing: 0.35em;
  text-transform: uppercase;
  color: var(--color-text-secondary);
}

.hero__scroll-line {
  width: 1px;
  height: 24px;
  background: var(--color-border);
}

/* =========================================================================
   Introduction
   ========================================================================= */
.feature-grid {
  display: grid;
  grid-template-columns: 1fr;
  border-top: 1px solid var(--color-border);
  margin-top: 64px;
}

.feature-grid__item {
  display: flex;
  align-items: flex-start;
  gap: 24px;
  padding: 32px 0;
  border-bottom: 1px solid var(--color-border);
}

.feature-grid__number {
  font-family: var(--font-condensed);
  font-weight: 700;
  font-size: 3.5rem;
  line-height: 1;
  color: var(--color-text-tertiary);
  flex: none;
}

.feature-grid__title {
  font-weight: 700;
  font-size: 21.6px;
  line-height: 1.5;
  margin-top: 6px;
}

.introduction__footer {
  display: flex;
  flex-direction: column;
  gap: 32px;
  padding-top: 64px;
}

.introduction__text {
  color: var(--color-text-secondary);
  font-size: 16px;
  line-height: 2.1;
  max-width: 32rem;
}

.introduction__watermark {
  font-weight: 900;
  font-size: 2.5rem;
  line-height: 1.25;
  color: var(--color-text-watermark-accent);
  text-align: right;
}

/* =========================================================================
   About
   ========================================================================= */
.about__intro {
  display: grid;
  grid-template-columns: 1fr;
  gap: 32px;
}

.about__intro .section__heading {
  margin-top: 0;
}

.about__lead {
  color: var(--color-text-secondary);
  font-size: 16px;
  line-height: 2.1;
  align-self: end;
}

.fact-list {
  border-top: 1px solid var(--color-border);
  margin-top: 64px;
}

.fact-list__item {
  display: grid;
  grid-template-columns: auto 1fr;
  column-gap: 24px;
  row-gap: 8px;
  align-items: start;
  padding: 32px 0;
  border-bottom: 1px solid var(--color-border);
}

.fact-list__number {
  font-family: var(--font-condensed);
  font-weight: 700;
  font-size: 3rem;
  line-height: 1;
  color: var(--color-text-tertiary);
  grid-row: 1 / span 2;
}

.fact-list__title {
  font-weight: 700;
  font-size: 17.6px;
}

.fact-list__desc {
  grid-column: 2;
  color: var(--color-text-secondary);
  font-size: 15.2px;
}

/* =========================================================================
   Kyushu
   ========================================================================= */
.kyushu {
  position: relative;
  overflow: hidden;
  padding-top: 96px;
  padding-bottom: 96px;
}

.kyushu__watermark {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-condensed);
  font-weight: 700;
  font-size: min(28vw, 320px);
  color: var(--color-text-watermark);
  white-space: nowrap;
  pointer-events: none;
  user-select: none;
}

.kyushu__inner {
  position: relative;
}

.kyushu__text {
  color: var(--color-text-secondary);
  font-size: 16px;
  line-height: 2.1;
  max-width: 42rem;
  margin-top: 40px;
}

/* =========================================================================
   Event
   ========================================================================= */
.event__date {
  display: flex;
  align-items: baseline;
  gap: 12px;
  font-family: var(--font-condensed);
  font-weight: 700;
  font-size: clamp(3.5rem, 10vw, 9rem);
  line-height: 1;
  color: var(--color-text-primary);
  margin-top: 32px;
  flex-wrap: wrap;
}

.event__date-divider {
  font-weight: 300;
  color: var(--color-text-tertiary);
}

.event__date-meta {
  font-family: var(--font-condensed);
  font-weight: 600;
  font-size: 24px;
  letter-spacing: 0.2em;
  color: var(--color-text-secondary);
  line-height: 1.5;
}

.event-list {
  border-top: 1px solid var(--color-border);
  margin-top: 64px;
}

.event-list__row {
  display: grid;
  grid-template-columns: 1fr;
  gap: 8px;
  padding: 20px 0;
  border-bottom: 1px solid var(--color-border);
}

.event-list__row dt {
  font-family: var(--font-mono);
  font-size: 20px;
  letter-spacing: 0.25em;
  text-transform: uppercase;
  color: var(--color-text-secondary);
}

.event-list__row dd {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 14px;
  font-weight: 500;
  font-size: 16px;
  margin-left: 0;
}

.event-list__row dd p {
  font-weight: 500;
}

/* --- イベント内のアクションボタン (マップ・カレンダー) --- */
.event-action {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 10px 18px;
  border: 1px solid var(--color-text-primary);
  color: var(--color-text-primary);
  font-family: var(--font-jp);
  font-weight: 600;
  font-size: 14px;
  line-height: 1;
  text-decoration: none;
  background: transparent;
  cursor: pointer;
  transition: background-color 0.15s ease, color 0.15s ease;
}

.event-action:hover,
.event-action:focus-visible {
  background: var(--color-text-primary);
  color: var(--color-bg-white);
}

.event-action__icon {
  width: 14px;
  height: 14px;
  flex: none;
}

summary.event-action {
  list-style: none;
}

summary.event-action::-webkit-details-marker,
summary.event-action::marker {
  display: none;
}

summary.event-action:focus-visible {
  outline: var(--focus-ring);
  outline-offset: 3px;
  border-radius: 2px;
}

.calendar-menu {
  position: relative;
}

.calendar-menu__chevron {
  width: 12px;
  height: 12px;
  flex: none;
  transition: transform 0.15s ease;
}

.calendar-menu[open] .calendar-menu__chevron {
  transform: rotate(180deg);
}

.calendar-menu__panel {
  position: absolute;
  top: calc(100% + 8px);
  left: 0;
  z-index: 5;
  display: flex;
  flex-direction: column;
  min-width: 240px;
  background: var(--color-bg-white);
  border: 1px solid var(--color-border);
  box-shadow: 0 8px 24px rgba(28, 28, 26, 0.14);
}

.calendar-menu__option {
  padding: 12px 16px;
  font-size: 14px;
  font-weight: 500;
  color: var(--color-text-primary);
  text-decoration: none;
  border-bottom: 1px solid var(--color-border);
}

.calendar-menu__option:last-child {
  border-bottom: none;
}

.calendar-menu__option:hover,
.calendar-menu__option:focus-visible {
  background: var(--color-bg);
}

.chip {
  display: inline-block;
  border: 1px solid var(--color-accent-border);
  color: var(--color-accent);
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.25em;
  text-transform: uppercase;
  padding: 5px 12px;
  border-radius: 999px;
}

/* =========================================================================
   Closing
   ========================================================================= */
.closing {
  padding-top: 112px;
  padding-bottom: 112px;
}

.closing__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 32px;
}

.closing__grid .section__heading {
  margin-top: 0;
}

.closing__text {
  color: var(--color-text-secondary);
  font-size: 16px;
  line-height: 2.2;
}

.closing__updates {
  display: flex;
  gap: 24px;
  align-items: flex-start;
  border-top: 1px solid var(--color-border);
  border-bottom: 1px solid var(--color-border);
  padding: 40px 0;
  margin-top: 80px;
}

.closing__arrow {
  font-family: var(--font-condensed);
  font-weight: 700;
  font-size: 2.5rem;
  line-height: 1;
  color: var(--color-text-tertiary);
  flex: none;
}

.closing__updates-title {
  font-weight: 700;
  font-size: 19.2px;
  line-height: 1.5;
  margin-top: 8px;
}

.closing__updates-desc {
  color: var(--color-text-secondary);
  font-size: 15.2px;
  margin-top: 8px;
}

.closing__final {
  text-align: center;
  padding-top: 80px;
}

.closing__final-heading {
  font-weight: 900;
  font-size: clamp(2.5rem, 10vw, 9rem);
  line-height: 1.05;
  color: var(--color-accent-vermillion);
}

.closing__final-meta {
  display: flex;
  flex-direction: column;
  gap: 8px;
  align-items: center;
  margin-top: 32px;
}

.closing__final-label {
  font-family: var(--font-condensed);
  font-weight: 600;
  font-size: 16px;
  letter-spacing: 0.3em;
  text-transform: uppercase;
  color: var(--color-text-secondary);
}

.closing__final-date {
  font-family: var(--font-condensed);
  font-weight: 500;
  font-size: 14.4px;
  letter-spacing: 0.25em;
  color: var(--color-text-tertiary);
}

/* =========================================================================
   フッター
   ========================================================================= */
.site-footer {
  background: var(--color-bg-dark);
  color: var(--color-footer-text);
  padding: 56px 24px;
}

.site-footer__inner {
  max-width: var(--container-max);
  margin: 0 auto;
}

.site-footer__top {
  display: grid;
  grid-template-columns: 1fr;
  gap: 40px;
}

.site-footer__logo {
  display: inline-block;
  border: 1px solid var(--color-border-dark);
  padding: 10px 16px;
  font-family: var(--font-condensed);
  font-size: 11px;
  letter-spacing: 0.3em;
  text-transform: uppercase;
  color: var(--color-footer-text-secondary);
  margin-bottom: 20px;
}

.site-footer__org-name {
  font-size: 11px;
  letter-spacing: 0.05em;
  color: var(--color-footer-text-muted);
  line-height: 1.9;
}

.site-footer__nav ul {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.site-footer__nav a {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  font-size: 11px;
  letter-spacing: 0.05em;
  color: var(--color-footer-text-secondary);
  text-decoration: underline;
  text-decoration-color: rgba(255, 255, 255, 0.3);
  text-underline-offset: 3px;
}

.site-footer__nav a:hover,
.site-footer__nav a:focus-visible {
  color: var(--color-footer-text);
  text-decoration-color: currentColor;
}

.site-footer__nav a::before {
  content: "";
  width: 12px;
  height: 1px;
  background: currentColor;
  opacity: 0.5;
  flex: none;
}

.site-footer__bottom {
  display: flex;
  flex-direction: column;
  gap: 8px;
  border-top: 1px solid var(--color-border-dark);
  margin-top: 48px;
  padding-top: 24px;
}

.site-footer__bottom p {
  font-family: var(--font-condensed);
  font-size: 10px;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--color-footer-text-muted);
}

/* =========================================================================
   プライバシーポリシー等の規約ページ
   ========================================================================= */
.legal__updated {
  margin-top: 16px;
}

.legal__lead {
  color: var(--color-text-secondary);
  font-size: 16px;
  line-height: 2;
  max-width: 42rem;
  margin-top: 32px;
}

.legal__section {
  border-top: 1px solid var(--color-border);
  padding-top: 32px;
  margin-top: 48px;
}

.legal__section-title {
  font-weight: 700;
  font-size: 21.6px;
  line-height: 1.5;
}

.legal__section p {
  color: var(--color-text-secondary);
  font-size: 16px;
  line-height: 2;
  max-width: 42rem;
}

.legal__section p + p {
  margin-top: 16px;
}

.legal__section-title + p {
  margin-top: 16px;
}

.legal__list {
  list-style: disc;
  color: var(--color-text-secondary);
  font-size: 16px;
  line-height: 2;
  max-width: 42rem;
  padding-left: 1.4em;
  margin-top: 16px;
}

.legal__list + p {
  margin-top: 16px;
}

.legal a {
  color: var(--color-accent);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.legal a:hover {
  color: var(--color-text-primary);
}

.legal__back {
  margin-top: 64px;
}



/* =========================================================================
   レスポンシブ (スマートフォン): ファーストビューの余白を圧縮し、
   iPhone 12 (390×844) でも「参加無料」まで画面内に収まるようにする
   ========================================================================= */
@media (max-width: 767px) {
  .site-header__inner {
    padding: 8px 20px;
  }

  .hero {
    padding: 12px 20px 0;
  }

  .hero__grid {
    gap: 14px;
    padding-bottom: 10px;
  }

  .hero__main {
    gap: 6px;
  }

  .hero__heading {
    font-size: clamp(2.8rem, 15vw, 13rem);
    margin-top: 2px;
  }

  .hero__lead {
    line-height: 1.3;
  }

  .hero__location {
    margin-top: 4px;
  }

  .hero__location-prefix {
    font-size: clamp(1.1rem, 4vw, 3.2rem);
  }

  .hero__location-main {
    font-size: clamp(2.2rem, 12vw, 9.9rem);
  }

  .hero__info {
    gap: 12px;
    padding-top: 8px;
  }

  .hero__date {
    font-size: clamp(3.2rem, 13vw, 10rem);
    margin-top: 0;
  }

  .hero__date-day {
    margin-top: 0;
  }

  .hero__info-block {
    gap: 4px;
  }

  .hero__info-block hr.rule {
    margin: 4px 0;
  }

  .hero__entry {
    margin-top: 0;
  }

  .hero__scroll {
    padding-bottom: 6px;
  }
}

/* =========================================================================
   レスポンシブ (タブレット以上)
   ========================================================================= */
@media (min-width: 768px) {
  .section {
    padding: 128px 40px;
  }

  .hero {
    padding: 40px 40px 0;
  }

  .site-header__inner {
    padding: 12px 40px;
  }

  .feature-grid,
  .fact-list {
    grid-template-columns: 1fr 1fr;
  }

  .feature-grid__item:nth-child(odd) {
    border-right: 1px solid var(--color-border);
    padding-right: 40px;
  }

  .feature-grid__item:nth-child(even) {
    padding-left: 40px;
  }

  .fact-list__item:nth-child(odd) {
    border-right: 1px solid var(--color-border);
    padding-right: 40px;
  }

  .fact-list__item:nth-child(even) {
   padding-left: 40px;
  }

  .about__intro {
    grid-template-columns: 1fr 1fr;
    gap: 64px;
  }

  .about__intro .section__heading {
    grid-row: 1;
  }

  .closing__grid {
    grid-template-columns: minmax(0, max-content) 1fr;
    gap: 64px;
  }

  .event-list__row {
    grid-template-columns: 144px 1fr;
    align-items: start;
  }

  .site-footer__top {
    grid-template-columns: 2fr 1fr;
  }
}

@media (min-width: 1080px) {
  .hero__grid {
    grid-template-columns: 1fr 360px;
  }

  .hero__info {
    border-top: none;
    border-left: 1px solid var(--color-border);
    padding-top: 0;
    padding-left: 40px;
  }
}

/* =========================================================================
   印刷時: 装飾を簡略化
   ========================================================================= */
@media print {
  .hero__scroll,
  .kyushu__watermark,
  .introduction__watermark,
  .skip-link,
  .intro {
    display: none;
  }
}