/* ===========================
   CSS Variables & Reset
   =========================== */
:root {
  --primary: #11c02bcf;
  --primary-light: #3b82f6;
  --primary-dark: #1240c0;
  --accent: #f59e0b;
  --accent-light: #fcd34d;
  --green: #10b981;
  --dark: #0f172a;
  --dark-mid: #1e293b;
  --dark-light: #334155;
  --gray: #64748b;
  --gray-light: #94a3b8;
  --border: #e2e8f0;
  --bg: #f8fafc;
  --bg-alt: #f1f5f9;
  --white: #ffffff;
  --text: #1e293b;
  --text-muted: #64748b;

  --font-display: 'Zen Maru Gothic', sans-serif;
  --font-body: 'Noto Sans JP', sans-serif;

  --shadow-sm: 0 1px 3px rgba(0,0,0,0.08), 0 1px 2px rgba(0,0,0,0.06);
  --shadow-md: 0 4px 16px rgba(0,0,0,0.10);
  --shadow-lg: 0 12px 40px rgba(0,0,0,0.14);
  --radius: 12px;
  --radius-lg: 20px;
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: smooth; font-size: 16px; }

body {
  font-family: var(--font-body);
  color: var(--text);
  background: var(--white);
  line-height: 1.7;
  overflow-x: hidden;
}

img { max-width: 100%; display: block; }
a { color: var(--primary); text-decoration: none; }
a:hover { text-decoration: underline; }

ul { list-style: none; }

/* ===========================
   Navigation
   =========================== */
.nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 100;
  background: rgba(255,255,255,0.92);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
  transition: box-shadow 0.3s;
}
.nav.scrolled { box-shadow: var(--shadow-md); }

.nav-inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 1.5rem;
  height: 64px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.nav-logo {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  color: var(--text);
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 0.85rem;
  line-height: 1.3;
  text-decoration: none;
}
.nav-logo:hover { text-decoration: none; }

.nav-logo-badge {
  background: var(--primary);
  color: white;
  font-size: 0.8rem;
  font-weight: 900;
  padding: 4px 8px;
  border-radius: 6px;
  letter-spacing: 0.05em;
  flex-shrink: 0;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 0.25rem;
}
.nav-links a {
  color: var(--text-muted);
  font-size: 0.875rem;
  padding: 0.4rem 0.8rem;
  border-radius: 8px;
  transition: color 0.2s, background 0.2s;
  text-decoration: none;
}
.nav-links a:hover { color: var(--primary); background: var(--bg); }

.nav-cta {
  background: var(--primary) !important;
  color: white !important;
  padding: 0.5rem 1.1rem !important;
  border-radius: 8px !important;
  font-weight: 500;
}
.nav-cta:hover { background: var(--primary-dark) !important; }

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 6px;
}
.nav-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--text);
  border-radius: 2px;
  transition: 0.3s;
}

/* ===========================
   Buttons
   =========================== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.75rem 1.75rem;
  border-radius: 10px;
  font-family: var(--font-body);
  font-size: 0.95rem;
  font-weight: 700;
  cursor: pointer;
  transition: all 0.2s;
  text-decoration: none;
  border: 2px solid transparent;
}
.btn-primary {
  background: var(--primary);
  color: white;
  box-shadow: 0 4px 16px rgba(26,86,232,0.3);
}
.btn-primary:hover {
  background: var(--primary-dark);
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(26,86,232,0.4);
  text-decoration: none;
  color: white;
}
.btn-outline {
  border-color: rgba(255,255,255,0.5);
  color: white;
}
.btn-outline:hover {
  border-color: white;
  background: rgba(255,255,255,0.12);
  text-decoration: none;
  color: white;
}
.btn-large { padding: 1rem 2.5rem; font-size: 1.05rem; }

/* ===========================
   Hero
   =========================== */
.hero {
  position: relative;
  min-height: 100vh;
  background: linear-gradient(135deg, #0f172a 0%, #38cb0b 50%, #ca691a 100%);
  display: flex;
  align-items: center;
  overflow: hidden;
  padding-top: 64px;
}

.hero-bg { position: absolute; inset: 0; pointer-events: none; }

.hero-orb {
  position: absolute;
  border-radius: 50%;
  filter: blur(80px);
  opacity: 0.4;
}
.hero-orb-1 {
  width: 500px; height: 500px;
  background: radial-gradient(circle, #3b82f6, transparent);
  top: -100px; right: -100px;
  animation: float1 8s ease-in-out infinite;
}
.hero-orb-2 {
  width: 350px; height: 350px;
  background: radial-gradient(circle, #f59e0b, transparent);
  bottom: -50px; left: -50px;
  animation: float2 10s ease-in-out infinite;
}
.hero-orb-3 {
  width: 250px; height: 250px;
  background: radial-gradient(circle, #10b981, transparent);
  top: 40%; left: 30%;
  animation: float1 12s ease-in-out infinite reverse;
}

.hero-grid {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(255,255,255,0.04) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,0.04) 1px, transparent 1px);
  background-size: 60px 60px;
}

@keyframes float1 {
  0%, 100% { transform: translate(0, 0) scale(1); }
  33% { transform: translate(30px, -20px) scale(1.05); }
  66% { transform: translate(-20px, 30px) scale(0.95); }
}
@keyframes float2 {
  0%, 100% { transform: translate(0, 0); }
  50% { transform: translate(40px, -30px); }
}

.hero-inner {
  position: relative;
  z-index: 1;
  max-width: 1200px;
  margin: 0 auto;
  padding: 4rem 1.5rem;
  animation: fadeInUp 0.8s ease both;
}

@keyframes fadeInUp {
  from { opacity: 0; transform: translateY(30px); }
  to { opacity: 1; transform: translateY(0); }
}

.hero-badge {
  display: inline-block;
  background: rgba(245,158,11,0.2);
  border: 1px solid rgba(245,158,11,0.5);
  color: var(--accent-light);
  padding: 0.4rem 1rem;
  border-radius: 100px;
  font-size: 0.9rem;
  font-weight: 700;
  margin-bottom: 1.5rem;
  letter-spacing: 0.03em;
}

.hero-title {
  font-family: var(--font-display);
  font-size: clamp(2.8rem, 8vw, 6rem);
  font-weight: 900;
  color: white;
  line-height: 1.1;
  letter-spacing: -0.02em;
  margin-bottom: 0.5rem;
}
.hero-title-sub {
  display: block;
  font-size: clamp(1rem, 3vw, 1.5rem);
  font-weight: 700;
  color: var(--accent-light);
  letter-spacing: 0.1em;
  margin-bottom: 0.25rem;
  text-align: left;
}

.hero-location {
  font-size: 1.4rem;
  color: rgba(255,255,255,0.7);
  font-weight: 500;
  margin-bottom: 1.5rem;
  font-family: var(--font-display);
}

.hero-desc {
  font-size: 1.05rem;
  color: rgba(255,255,255,0.82);
  max-width: 520px;
  margin-bottom: 2.5rem;
  line-height: 1.8;
}
.hero-desc strong {
  color: var(--accent-light);
  font-weight: 700;
}

.hero-actions {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
}

.hero-scroll-indicator {
  position: absolute;
  bottom: 2rem;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.5rem;
  color: rgba(255,255,255,0.4);
  font-size: 0.7rem;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  animation: fadeIn 2s 1s both;
}
@keyframes fadeIn { from { opacity: 0; } to { opacity: 1; } }

.hero-scroll-line {
  width: 1px;
  height: 40px;
  background: linear-gradient(to bottom, rgba(255,255,255,0.4), transparent);
  animation: scrollLine 2s ease-in-out infinite;
}
@keyframes scrollLine {
  0% { transform: scaleY(0); transform-origin: top; }
  50% { transform: scaleY(1); transform-origin: top; }
  50.01% { transform: scaleY(1); transform-origin: bottom; }
  100% { transform: scaleY(0); transform-origin: bottom; }
}

/* ===========================
   Sections
   =========================== */
.section { padding: 6rem 0; }
.section-alt { background: var(--bg-alt); }
.section-dark {
  background: var(--dark);
  color: white;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 1.5rem;
}

.section-header {
  text-align: center;
  margin-bottom: 4rem;
}
.section-header-light .section-label { color: rgba(255,255,255,0.5); }
.section-header-light .section-title { color: white; }

.section-label {
  display: block;
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--primary);
  margin-bottom: 0.5rem;
}

.section-title {
  font-family: var(--font-display);
  font-size: clamp(1.8rem, 4vw, 2.8rem);
  font-weight: 900;
  color: var(--dark);
  letter-spacing: -0.02em;
}

/* ===========================
   About
   =========================== */
.about-grid {
  display: grid;
  grid-template-columns: 1fr 1.4fr;
  gap: 4rem;
  align-items: start;
}

.about-lead {
  font-size: 1.1rem;
  line-height: 1.8;
  color: var(--text);
  margin-bottom: 1rem;
}

.about-cards {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

.about-card {
  background: white;
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 1.75rem;
  box-shadow: var(--shadow-sm);
  transition: box-shadow 0.3s, transform 0.3s;
}
.about-card:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-3px);
}

.about-card-icon {
  font-size: 2rem;
  margin-bottom: 1rem;
}

.about-card h3 {
  font-family: var(--font-display);
  font-size: 1.15rem;
  font-weight: 700;
  margin-bottom: 0.75rem;
  color: var(--dark);
}

.about-card ul {
  margin-top: 0.75rem;
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}
.about-card li {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.9rem;
}

.tag {
  display: inline-block;
  font-size: 0.72rem;
  font-weight: 700;
  padding: 2px 8px;
  border-radius: 100px;
  letter-spacing: 0.04em;
  flex-shrink: 0;
}
.tag-blue { background: #dbeafe; color: #1e40af; }
.tag-green { background: #d1fae5; color: #065f46; }

/* ===========================
   Stats
   =========================== */
.stats-section {
  background: var(--primary);
  padding: 4rem 0;
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 2rem;
  text-align: center;
}

.stat-item { color: white; }

.stat-number {
  font-family: var(--font-display);
  font-size: clamp(2.5rem, 6vw, 4rem);
  font-weight: 900;
  line-height: 1;
  margin-bottom: 0.5rem;
  color: var(--accent-light);
}

.stat-label {
  font-size: 1rem;
  font-weight: 700;
  margin-bottom: 0.4rem;
}

.stat-desc {
  font-size: 0.82rem;
  color: rgba(255,255,255,0.7);
}

/* ===========================
   Timeline
   =========================== */
.timeline {
  max-width: 700px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 0;
}

.timeline-item {
  display: flex;
  gap: 2rem;
  position: relative;
}
.timeline-item:not(:last-child)::before {
  content: '';
  position: absolute;
  left: 20px;
  top: 44px;
  bottom: -24px;
  width: 2px;
  background: linear-gradient(to bottom, var(--primary), var(--border));
}

.timeline-dot {
  width: 42px;
  height: 42px;
  border-radius: 50%;
  background: var(--primary);
  color: white;
  font-weight: 900;
  font-family: var(--font-display);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1rem;
  flex-shrink: 0;
  box-shadow: 0 4px 12px rgba(26,86,232,0.35);
  z-index: 1;
  position: relative;
}

.timeline-content {
  padding-bottom: 2.5rem;
  padding-top: 0.5rem;
}

.timeline-date {
  font-size: 0.8rem;
  font-weight: 700;
  color: var(--primary);
  letter-spacing: 0.05em;
  margin-bottom: 0.35rem;
  text-transform: uppercase;
}

.timeline-content h3 {
  font-family: var(--font-display);
  font-size: 1.25rem;
  font-weight: 700;
  margin-bottom: 0.5rem;
  color: var(--dark);
}

/* ===========================
   Venue
   =========================== */
.venue-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 3rem;
  align-items: start;
}

.venue-name {
  font-family: var(--font-display);
  font-size: 1.4rem;
  font-weight: 700;
  margin-bottom: 0.75rem;
  line-height: 1.4;
}
.venue-name small { font-size: 0.9rem; color: var(--text-muted); }

.venue-address {
  font-size: 0.9rem;
  color: var(--text-muted);
  margin-bottom: 1.5rem;
  line-height: 1.7;
}

.venue-access {
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}

.venue-access-block {
  display: flex;
  gap: 1rem;
  align-items: flex-start;
}

.venue-access-icon { font-size: 1.5rem; flex-shrink: 0; margin-top: 2px; }

.venue-access-block strong { display: block; margin-bottom: 0.4rem; font-size: 0.95rem; }
.venue-access-block ul { padding-left: 1.1rem; list-style: disc; font-size: 0.88rem; color: var(--text-muted); }
.venue-access-block ul li { margin-bottom: 0.25rem; }
.venue-access-block p { font-size: 0.88rem; color: var(--text-muted); }

/* ===========================
   Purpose
   =========================== */
.purpose-quote {
  font-family: var(--font-display);
  font-size: clamp(1.3rem, 3vw, 1.9rem);
  font-weight: 700;
  text-align: center;
  color: var(--accent-light);
  border-left: none;
  margin: 0 auto 3rem;
  max-width: 680px;
  padding: 2rem;
  background: rgba(255,255,255,0.06);
  border-radius: var(--radius-lg);
  border: 1px solid rgba(255,255,255,0.12);
  line-height: 1.5;
}

.purpose-text {
  max-width: 800px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}
.purpose-text p { color: rgba(255,255,255,0.82); line-height: 1.9; }

/* ===========================
   Message quote
   =========================== */
.message-quote {
  font-family: var(--font-display);
  font-size: 1.2rem;
  font-weight: 700;
  text-align: center;
  color: var(--primary);
  max-width: 680px;
  margin: 0 auto 3.5rem;
  padding: 1.75rem 2rem;
  background: #eff6ff;
  border-radius: var(--radius-lg);
  border-left: 4px solid var(--primary);
  line-height: 1.6;
}

/* ===========================
   Steps
   =========================== */
.steps-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1.5rem;
}

.step-card {
  background: white;
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 2rem 1.5rem;
  box-shadow: var(--shadow-sm);
  transition: box-shadow 0.3s, transform 0.3s;
  position: relative;
  overflow: hidden;
}
.step-card::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--primary), var(--primary-light));
}
.step-card:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-4px);
}

.step-number {
  font-family: var(--font-display);
  font-size: 2.5rem;
  font-weight: 900;
  color: var(--border);
  line-height: 1;
  margin-bottom: 0.75rem;
  letter-spacing: -0.03em;
}

.step-card h3 {
  font-family: var(--font-display);
  font-size: 1rem;
  font-weight: 700;
  margin-bottom: 0.6rem;
  color: var(--dark);
}

.step-card p {
  font-size: 0.875rem;
  color: var(--text-muted);
  line-height: 1.7;
}

/* ===========================
   News
   =========================== */
.news-list {
  display: flex;
  flex-direction: column;
  gap: 0;
  max-width: 860px;
  margin: 0 auto;
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  background: white;
}

.news-item {
  display: grid;
  grid-template-columns: 120px 1fr;
  gap: 1rem;
  align-items: start;
  padding: 1.25rem 1.75rem;
  border-bottom: 1px solid var(--border);
  transition: background 0.2s;
}
.news-item:last-child { border-bottom: none; }
.news-item:hover { background: var(--bg); }
.news-item-new { background: #eff6ff; }
.news-item-new:hover { background: #dbeafe; }

.news-date {
  font-size: 0.8rem;
  font-weight: 700;
  color: var(--gray);
  padding-top: 2px;
  letter-spacing: 0.05em;
}

.news-badge {
  display: inline-block;
  background: var(--primary);
  color: white;
  font-size: 0.65rem;
  font-weight: 700;
  padding: 2px 8px;
  border-radius: 4px;
  letter-spacing: 0.08em;
  vertical-align: middle;
  margin-right: 0.5rem;
}

.news-text {
  font-size: 0.9rem;
  line-height: 1.7;
}

/* ===========================
   Organization
   =========================== */
.org-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr;
  gap: 1.5rem;
  margin-bottom: 4rem;
}

.org-card {
  background: white;
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 1.75rem;
  box-shadow: var(--shadow-sm);
}
.org-card-main {
  border-top: 3px solid var(--primary);
}

.org-role {
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--primary);
  margin-bottom: 0.75rem;
}

.org-card h3 {
  font-family: var(--font-display);
  font-size: 1rem;
  font-weight: 700;
  margin-bottom: 0.75rem;
  color: var(--dark);
  line-height: 1.4;
}

.org-card ul {
  margin-bottom: 0.75rem;
}
.org-card ul li {
  font-size: 0.9rem;
  color: var(--text);
  padding: 0.2rem 0;
  padding-left: 1rem;
  position: relative;
}
.org-card ul li::before {
  content: '▸';
  position: absolute;
  left: 0;
  color: var(--primary);
  font-size: 0.7rem;
}

.org-card p {
  font-size: 0.85rem;
  color: var(--text-muted);
  line-height: 1.7;
}

/* Sponsors */
.sponsors-title {
  font-family: var(--font-display);
  font-size: 1.3rem;
  font-weight: 700;
  text-align: center;
  margin-bottom: 0.75rem;
  color: var(--dark);
}

.sponsors-desc {
  text-align: center;
  color: var(--text-muted);
  font-size: 0.9rem;
  margin-bottom: 2rem;
}

.sponsors-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.25rem;
}

.sponsor-card {
  background: rgb(136, 180, 211);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.5rem;
  text-align: center;
  box-shadow: var(--shadow-sm);
  transition: box-shadow 0.3s, transform 0.3s;
}
.sponsor-card:hover { box-shadow: var(--shadow-md); transform: translateY(-3px); }

.sponsor-name {
  font-family: var(--font-display);
  font-size: 1.50rem;
  font-weight: 700;
  color: var(--dark);
  margin-bottom: 0.5rem;
}

.sponsor-card a {
  font-size: 0.8rem;
  color: var(--primary);
}

/* ===========================
   CTA Section
   =========================== */
.cta-section {
  background: linear-gradient(135deg, var(--dark) 0%, #1e3a8a 100%);
  padding: 6rem 0;
  text-align: center;
}

.cta-section h2 {
  font-family: var(--font-display);
  font-size: clamp(1.8rem, 4vw, 2.8rem);
  font-weight: 900;
  color: white;
  margin-bottom: 1rem;
}

.cta-section p {
  color: rgba(255,255,255,0.75);
  font-size: 1.05rem;
  margin-bottom: 2.5rem;
}

/* ===========================
   Footer
   =========================== */
.footer {
  background: var(--dark);
  padding: 2rem 0;
  border-top: 1px solid rgba(255,255,255,0.08);
}

.footer-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  flex-wrap: wrap;
}

.footer-logo {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  color: rgba(255,255,255,0.7);
  font-size: 0.9rem;
}

.footer-copy {
  font-size: 0.8rem;
  color: rgba(255,255,255,0.4);
}

/* ===========================
   Animations / Intersection Observer
   =========================== */
.reveal {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.7s ease, transform 0.7s ease;
}
.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}
.reveal-delay-1 { transition-delay: 0.1s; }
.reveal-delay-2 { transition-delay: 0.2s; }
.reveal-delay-3 { transition-delay: 0.3s; }
.reveal-delay-4 { transition-delay: 0.4s; }

/* ===========================
   Hero Images Collage
   =========================== */
.hero-inner {
  display: block;
  width: 100%;
}

.hero-images {
  position: relative;
  z-index: 1;
}

.hero-img-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  grid-template-rows: 200px 200px;
  gap: 10px;
  border-radius: var(--radius-lg);
  overflow: hidden;
}

.hero-img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.6s ease, filter 0.4s ease;
  filter: brightness(0.88) saturate(1.1);
}
.hero-img:hover { transform: scale(1.05); filter: brightness(1) saturate(1.2); }

.hero-img-1 { border-radius: 14px 0 0 0; }
.hero-img-2 { border-radius: 0 14px 0 0; }
.hero-img-3 { border-radius: 0 0 0 14px; }
.hero-img-4 { border-radius: 0 0 14px 0; }

/* ===========================
   About Hero Image
   =========================== */
.about-hero-img {
  position: relative;
  border-radius: var(--radius-lg);
  overflow: hidden;
  margin-bottom: 1.75rem;
  box-shadow: var(--shadow-lg);
}
.about-hero-img img {
  width: 100%;
  height: 280px;
  object-fit: cover;
  display: block;
  transition: transform 0.5s ease;
}
.about-hero-img:hover img { transform: scale(1.03); }

.about-img-caption {
  position: absolute;
  bottom: 0; left: 0; right: 0;
  background: linear-gradient(to top, rgba(15,23,42,0.85), transparent);
  color: rgba(255,255,255,0.9);
  font-size: 0.82rem;
  font-weight: 500;
  padding: 1.5rem 1rem 0.75rem;
  letter-spacing: 0.03em;
}

/* ===========================
   Gallery
   =========================== */
.gallery-grid {
  display: grid;
  grid-template-columns: 1.6fr 1fr 1fr;
  grid-template-rows: 240px 240px;
  gap: 10px;
  border-radius: var(--radius-lg);
  overflow: hidden;
  margin-bottom: 1rem;
}

.gallery-item {
  position: relative;
  overflow: hidden;
  cursor: pointer;
}
.gallery-item-large {
  grid-row: span 2;
}

.gallery-item img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.5s ease, filter 0.4s ease;
  filter: brightness(0.9);
}
.gallery-item:hover img {
  transform: scale(1.07);
  filter: brightness(0.7);
}

.gallery-overlay {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: flex-end;
  padding: 1rem;
  background: linear-gradient(to top, rgba(15,23,42,0.75) 0%, transparent 60%);
  opacity: 0;
  transition: opacity 0.35s ease;
}
.gallery-item:hover .gallery-overlay { opacity: 1; }
.gallery-overlay span {
  color: white;
  font-size: 0.85rem;
  font-weight: 700;
  letter-spacing: 0.05em;
}

.gallery-note {
  text-align: center;
  font-size: 0.8rem;
  color: var(--text-muted);
  margin-top: 0.5rem;
}

/* ===========================
   Responsive (画像追加分)
   =========================== */
@media (max-width: 1024px) {
  .hero-inner {
    grid-template-columns: 1fr;
  }
  .hero-images { display: none; }

  .gallery-grid {
    grid-template-columns: 1fr 1fr;
    grid-template-rows: auto;
  }
  .gallery-item-large { grid-row: span 1; }
}

@media (max-width: 600px) {
  .gallery-grid {
    grid-template-columns: 1fr 1fr;
    grid-template-rows: 150px 150px 150px;
  }
  .gallery-item:nth-child(n+4) { display: none; }
  .hero-img-grid { grid-template-rows: 150px 150px; }
}

/* ===========================
   Responsive
   =========================== */
@media (max-width: 1024px) {
  .about-grid { grid-template-columns: 1fr; gap: 2.5rem; }
  .steps-grid { grid-template-columns: repeat(2, 1fr); }
  .org-grid { grid-template-columns: 1fr 1fr; }
  .org-card-main { grid-column: span 2; }
}

@media (max-width: 768px) {
  .nav-links {
    display: none;
    position: absolute;
    top: 64px; left: 0; right: 0;
    background: white;
    flex-direction: column;
    padding: 1rem;
    border-bottom: 1px solid var(--border);
    box-shadow: var(--shadow-md);
    gap: 0.25rem;
  }
  .nav-links.open { display: flex; }
  .nav-links a { width: 100%; }
  .nav-toggle { display: flex; }

  .hero-inner { padding: 3rem 1.5rem; }
  .section { padding: 4rem 0; }

  .stats-grid { grid-template-columns: 1fr; gap: 2rem; }
  .steps-grid { grid-template-columns: 1fr; }
  .venue-grid { grid-template-columns: 1fr; }
  .org-grid { grid-template-columns: 1fr; }
  .org-card-main { grid-column: span 1; }
  .sponsors-grid { grid-template-columns: 1fr; }

  .news-item { grid-template-columns: 1fr; gap: 0.25rem; }
  .news-date { font-size: 0.75rem; }

  .hero-actions { flex-direction: column; align-items: flex-start; }
  .footer-inner { flex-direction: column; text-align: center; }
}

@media (max-width: 480px) {
  .hero-title { font-size: 2.5rem; }
  .section-title { font-size: 1.6rem; }
}