:root{
  --bg:#ffffff;
  --fg:#0f1724;
  --accent:#2563eb;
  --muted:#6b7280;
  --container:1100px;
}
*{box-sizing:border-box}
html,body{height:100%;scroll-behavior:smooth}
body{margin:0;font-family:Inter,system-ui,-apple-system,"Helvetica Neue",Arial; color:var(--fg);background:var(--bg);line-height:1.5;overflow-x:hidden}
.container{max-width:var(--container);margin:0 auto;padding:1.25rem}
.site-header{background:linear-gradient(90deg,#fff 0 70%,#000 70% 100%);border-bottom:0;position: sticky;top:0;z-index:100}
.header-inner{display:grid;grid-template-columns:minmax(0,1.4fr) minmax(160px,.45fr) minmax(420px,1.75fr);align-items:stretch;gap:0;padding:0}
.header-panel{min-height:72px;display:flex;align-items:center;position:relative;padding:.75rem 1.25rem}
.header-brand{background:#fff;clip-path:polygon(0 0,calc(100% - 40px) 0,100% 100%,0 100%);z-index:1;padding-right:2.4rem}
.header-app{background:hsl(216, 12%, 84%);clip-path:polygon(40px 0,100% 0,calc(100% - 40px) 100%,0 100%);margin-left:-40px;z-index:2;justify-content:center;padding-inline:1.75rem;text-align: center;}
.header-menu{background:#000;clip-path:polygon(40px 0,100% 0,100% 100%,0 100%);margin-left:-40px;z-index:3;justify-content:flex-end;padding-left:2.8rem;gap:1rem}
.header-menu::after{content:"";position:absolute;top:0;left:100%;width:100vw;height:100%;background:#000}
.site-header .logo{color:#111}
.brand{display:flex;align-items:center;gap:.55rem;text-decoration:none}
.logo-text-group{display:flex;flex-direction:column;align-items:flex-start;line-height:1.1}
.logo{margin:0;font-size:1.25rem;line-height:1.1}
.logo-catchphrase{font-size:.6rem;font-weight:500;color:#6b7280;white-space:nowrap;margin-top:.15rem}
.logo-icon{width:30px;height:30px;object-fit:contain;border-radius:8px;flex:0 0 auto}
.webapp-button{display:inline-flex;align-items:center;justify-content:center;padding:0;background:transparent;color:#111;text-decoration:none;font-weight:600;white-space:nowrap;box-shadow:none}
.webapp-button:hover{color:#000;text-decoration:underline}
.header-menu .site-nav{display:flex;gap:1rem}
.header-menu .site-nav a{margin-left:0;color:#fff}
.header-menu .site-nav a:hover{color:#e5e7eb}
.menu-toggle{display:none;background:transparent;border:0;padding:10px;width:44px;height:44px;cursor:pointer;align-items:center;justify-content:center}
.hamburger{display:block;width:22px;height:2px;background:#fff;position:relative;border-radius:2px}
.hamburger::before,.hamburger::after{content:"";position:absolute;left:0;width:22px;height:2px;background:#fff;border-radius:2px}
.hamburger::before{top:-7px}
.hamburger::after{top:7px}
/* 宣伝バナー全体の背景と枠線 */
.promo-banner {background: #000;opacity: 1;display: flex;align-items: center;}
.promo-inner {display: flex;align-items: center;gap: 2.5rem;padding: 0;width: 100%;}
.promo-image {flex: 1 1 60%;text-align: center;background-color: #000;display: flex;align-items: center;justify-content: center;}
.promo-image img {width: 100%;height: auto;display: block;margin: 0 auto;}
.promo-content {flex: 1 1 40%;text-align: left;display: flex;flex-direction: column;justify-content: center;gap: 12px;}
.promo-badge {background:#ff0000;color: #ffffff;font-size: 30px;font-weight: 700;display: inline-block;width: fit-content;}
.promo-title {margin: 0;font-size: 34px;color: #ffffff;font-weight: 800;line-height: 1.3;padding: 0.4rem 0.8rem;width: fit-content;}
.promo-text {margin: 0;font-size: 28px;color: #cbd5e1;line-height: 1.6;;padding: 0.6rem 1rem;width: fit-content;}
.about-image {max-width: 320px;width: 100%;height: auto;display: block;}
/* コンセプトセクション*/
.concept {padding: 2rem 0;background-color: #ffffff;text-align: left;border-bottom: 1px solid #f1f5f9;}
.concept-inner {margin: 0 auto;padding: 0 1.25rem;display: flex;}
.subtitle {display: inline-block;font-size: 30px;font-weight: 700;letter-spacing: 0.1em;color: #000;padding: 0.2rem 0.5rem;margin-bottom: 1.25rem;text-transform: uppercase;position: relative;margin-top: 8px;margin-left: 8px;border-width: 2px;border-style: solid;border-color: #000;}
.subtitle::before {content: '';position: absolute;top: -8px;left: -8px;width: 16px;height: 16px;border: 2px solid #000;box-sizing: border-box;pointer-events: none;}
.subtitle::after {content: '';position: absolute;bottom:-8px;right: -8px;width: 16px;height: 16px;border: 2px solid #000;box-sizing: border-box;pointer-events: none;background-color: #000;}
.concept-title {font-size: 24px;font-weight: 700;color: var(--fg);margin: 0 0 1.25rem 0;line-height: 1.4;}
.concept-lead {font-size: 15px;color: var(--muted);line-height: 1.75;margin: 0;}
.concept-image-block {width: 40%;margin-left: 10%;margin-right: 0%;margin-top: auto;margin-bottom: 0%;}
.concept-image-block img {width: 100%;height: auto;display: block;margin-top: auto;margin-bottom: 0%;}
/* アプリ提供セクション */
.apps {padding: 0rem 0;border-bottom: 1px solid #f1f5f9;}
.apps-inner {margin: 0 auto;padding: 1.25rem 0rem;}
section.apps.container {background-color: #ddd;}
.apps-grid {display: flex;gap: 1.5rem;margin-top: 1.5rem;}
.app-card {flex: 1 1 33.333%;padding: 2rem;border: 1px solid #e2e8f0;border-radius: 8px;background-color: #ffffff;display: flex;flex-direction: column;justify-content: space-between;min-height: 220px;}
.app-card h3 {font-size: 1.25rem;font-weight: 700;margin: 0 0 0.75rem 0;color: var(--fg);}
.app-card p {font-size: 0.9rem;color: var(--muted);line-height: 1.6;margin: 0 0 1.5rem 0;}
.app-btn {display: inline-block;text-align: center;padding: 0.6rem 1rem;background-color: #000;color: #fff;border-radius: 6px;text-decoration: none;font-size: 0.85rem;font-weight: 600;}
.app-btn:hover {background-color: #222;}
.apps-note {margin-top: 1rem;font-size: 0.9rem;color: #fff;background-color: #000;padding: 0.1rem 2rem;border-radius: 6px;}

@media (max-width:700px){
  .header-inner{grid-template-columns:minmax(0,1.25fr) minmax(120px,.5fr) minmax(72px,.28fr);grid-template-areas:none}
  .header-brand{grid-area:auto;clip-path:polygon(0 0,calc(100% - 28px) 0,100% 100%,0 100%);padding-right:1.2rem}
  .header-app{grid-area:auto;margin-left:-28px;clip-path:polygon(28px 0,100% 0,calc(100% - 28px) 100%,0 100%);justify-content:center;align-items:center;padding:.75rem 1rem;min-height:72px}
  .header-menu{grid-area:auto;margin-left:-28px;clip-path:none;background:transparent;position:relative;padding-left:1rem;padding-right:1rem;justify-content:flex-end;min-width:0}
  .header-menu::before{content:"";position:absolute;top:0;left:0;width:100%;height:100%;background:#000;clip-path:polygon(28px 0,100% 0,100% 100%,0 100%);z-index:-1}
  .header-menu::after{display:block;left:100%;width:100vw}
  .webapp-button{font-size:.92rem}
  .header-menu .site-nav{display:none;position:absolute;right:.8rem;top:calc(100% + .5rem);background:#fff;flex-direction:column;gap:.5rem;padding:.8rem;border-radius:8px;box-shadow:0 6px 18px rgba(16,24,40,0.08);z-index:1000}
  .header-menu .site-nav.open{display:flex}
  .header-menu .site-nav.open a{color:#000}
  .header-menu .site-nav.open a:hover{color:#111}
  .menu-toggle{display:flex}
  /* 宣伝バナー全体の背景と枠線 */
  .promo-banner {padding: 0;}
  .promo-inner {flex-direction: column;gap: 1.5rem;padding: 0;width: 100%;}
  .promo-image,.promo-content {flex: 1 1 auto;width: 100%;}
  .promo-image {padding-right: 0;}
  .promo-image img {width: 100vw;height: auto;margin-left: calc(50% - 50vw);margin-right: calc(50% - 50vw);}
  .promo-content {text-align: start;padding: 0 1.25rem;display: flex;flex-direction: column;align-items: flex-start;gap: 12px;}
  .promo-title {font-size: 30px;padding: 1px;}
  .promo-text {font-size: 20px;padding: 1px;padding-bottom: 10px;}
  /* スマホ画面で写真を画面幅いっぱいに広げる */
  .about-image {width: 100vw;margin-left: calc(50% - 50vw);margin-right: calc(50% - 50vw);max-width: none;}
  /* コンセプトセクション*/
  .concept {padding: 1rem 0;}
  .concept-title {font-size: 20px;line-height: 1.5;}
  .concept-lead {font-size: 14px;line-height: 1.7;}
  .concept-inner {flex-direction: column;gap: 1.5rem;}
  .subtitle {font-size: 25px;letter-spacing: 0.05em;margin-top: 0;margin-left: 0;}
  .concept-image-block {width: 100%;margin: 0;align-items: center;}
  .concept-image-block img {width: 70%;height: auto;display: block;margin: 0 auto;}
}
.site-nav a{margin-left:1rem;color:var(--muted);text-decoration:none}
.site-nav a:hover{color:var(--fg)}
.hero{padding:4rem 0;background:linear-gradient(180deg,#f8fafc,white)}
.hero-title{margin:0 0 .5rem;font-size:2rem}
.hero-sub{margin:0 0 1rem;color:var(--muted)}
.btn{display:inline-block;padding:.6rem 1rem;background:var(--accent);color:#fff;border-radius:6px;text-decoration:none}
.features{padding:3rem 0}
.grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(200px,1fr));gap:1rem;margin-top:1rem}
.card{padding:1rem;border:1px solid #eee;border-radius:8px;background:#fff}
.site-footer{border-top:1px solid #eee;padding:1rem 0;margin-top:2rem}
.footer-trademark{font-size:.7rem;color:var(--muted);margin-top:.75rem;line-height:1.4}
.footer-content {display:flex;align-items:center;justify-content:space-between;gap:1rem;flex-wrap:wrap;margin-bottom:0.75rem}
.footer-x-link {display:inline-flex;align-items:center;gap:0.6rem;color:#000;text-decoration:none;font-size:1.05rem;font-weight:700}
.footer-x-link:hover {text-decoration:underline}
.footer-x-link img.x-logo {width:20px;height:20px;object-fit:contain}
.contact a{color:var(--accent)}
/* ニュースセクション */
.news {padding: 0 1.25rem 3rem 1.25rem;border-bottom: 1px solid #f1f5f9;padding-top: 0rem;}
.news-inner {margin: 0 auto;padding: 1.25rem 0rem;}
.news-list {display: flex;flex-direction: column;gap: 0.75rem;margin-top: 1.5rem;}
.news-item {border: 1px solid #e2e8f0;border-radius: 6px;background-color: #ffffff;overflow: hidden;transition: border-color 0.2s;}
.news-item.active {border-color: #000;}
.news-item.hidden {display: none;}
.news-header {width: 100%;display: flex;align-items: center;gap: 1.5rem;padding: 1.25rem 1.5rem;background: none;border: none;text-align: left;cursor: pointer;font-family: inherit;}
.news-date {font-size: 0.9rem;color: var(--muted);flex-shrink: 0;}
.news-title {font-size: 1.05rem;font-weight: 700;color: var(--fg);margin: 0;flex-grow: 1;display: flex;align-items: center;gap: 0.5rem;}
.new-label {color: #000;font-weight: 900;}
.arrow-icon {width: 10px;height: 10px;border-top: 2px solid var(--muted);border-right: 2px solid var(--muted);transform: rotate(135deg);transition: transform 0.2s;flex-shrink: 0;}
.news-item.active .arrow-icon {transform: rotate(-45deg);border-color: #000;}
.news-body {display: none;padding: 0 1.5rem 1.5rem 1.5rem;border-top: 1px dashed #e2e8f0;margin-top: 0;background-color: #fafafa;}
.news-item.active .news-body {display: block;}
.news-content {font-size: 0.95rem;color: var(--fg);line-height: 1.7;margin: 1.25rem 0;}
.news-link-btn {display: inline-block;padding: 0.5rem 1rem;background-color: #000;color: #fff;border-radius: 4px;text-decoration: none;font-size: 0.85rem;font-weight: 600;transition: background-color 0.2s;}
.news-link-btn:hover {background-color: #222;}
.news-more-btn-container {text-align: center;margin-top: 1.5rem;}
.news-more-btn {display: inline-block;padding: 0.6rem 2rem;background-color: transparent;color: #000;border: 1px solid #000;border-radius: 4px;font-size: 0.9rem;font-weight: 600;cursor: pointer;transition: background-color 0.2s, color 0.2s;font-family: inherit;}
.news-more-btn:hover {background-color: #000;color: #fff;}

@media (max-width:600px){
  .hero{padding:2rem 0}
  .hero-title{font-size:1.5rem}
  .site-nav a{margin-left:.5rem}
}
/* アプリ提供セクション */
.apps {padding: 0 1.25rem 3rem 1.25rem;border-bottom: 1px solid #f1f5f9;}
.apps-grid {display: flex;gap: 1.5rem;margin-top: 1.5rem;}
.app-card {flex: 1 1 33.333%;padding: 2rem;border: 1px solid #e2e8f0;border-radius: 8px;background-color: #ffffff;display: flex;flex-direction: column;justify-content: space-between;min-height: 220px;position: relative;overflow: hidden;}
.app-card::after {content: '';position: absolute;bottom: 0;right: 0;width: 0;height: 0;border-style: solid;border-width: 0 0 40px 40px;border-color: transparent transparent #000 transparent;pointer-events: none;z-index: 1;}
.app-card h3 {font-size: 1.25rem;font-weight: 700;margin: 0 0 0.75rem 0;color: var(--fg);}
.app-card p {font-size: 0.9rem;color: var(--muted);line-height: 1.6;margin: 0 0 1.5rem 0;}
.app-btn {display: inline-block;text-align: center;padding: 0.6rem 1rem;background-color: #000;color: #fff;border-radius: 6px;text-decoration: none;font-size: 0.85rem;font-weight: 600;}
.app-btn:hover {background-color: #222;}
.app-store-btn img {height: 40px;display: block;}

@media (max-width:700px){
  .apps {padding: 0 1.25rem 2rem 1.25rem;}
  .apps-grid {flex-direction: column;gap: 1rem;}
  .app-card {width: 100%;min-height: auto;}
}

@media (max-width:700px){
  .news-header {flex-direction: column;align-items: flex-start;gap: 0.5rem;padding: 1rem;}
  .news-title {font-size: 0.95rem;}
  .news-body {padding: 0 1rem 1rem 1rem;}
}

/* サークル紹介セクション（カードデザイン） */
.about-team-section {padding: 3rem 1.25rem;border-bottom: 1px solid #f1f5f9;background-color: #f8fafc;}
.about-team-card {margin: 0 auto;padding: 2.5rem;background-color: #ffffff;border: 2px solid #000;border-radius: 12px;box-shadow: 4px 4px 0px rgba(0,0,0,0.15);position: relative;}
.about-team-content {margin-top: 1.5rem;}
.about-team-title {font-size: 24px;font-weight: 700;color: var(--fg);margin: 0 0 1.25rem 0;line-height: 1.4;}
.about-team-lead {font-size: 15px;color: var(--muted);line-height: 1.75;margin: 0 0 2rem 0;}
.about-team-btn-wrapper {text-align: left;}
.about-team-btn {display: inline-block;padding: 0.75rem 1.5rem;background-color: #000;color: #fff;border: 2px solid #000;border-radius: 6px;text-decoration: none;font-size: 0.9rem;font-weight: 600;transition: background-color 0.2s, color 0.2s;text-align: center;}
.about-team-btn:hover {background-color: transparent;color: #000;}
@media (max-width:700px){
  .about-team-section {padding: 2rem 1.25rem;}
  .about-team-card {padding: 1.5rem;}
  .about-team-title {font-size: 20px;line-height: 1.5;}
  .about-team-lead {margin-bottom: 1.5rem;}
}

/* 2カラム分割セクションレイアウト */
.split-section {display:flex;align-items:center;justify-content:center;padding:3.5rem 1.25rem;color:#fff}
.split-inner {display:flex;align-items:center;gap:4rem;max-width:var(--container);margin:0 auto;width:100%}
.split-image-block {flex:1 1 50%;max-width:500px}
.split-image-block img {width:100%;aspect-ratio:5 / 4;object-fit:cover;border-radius:8px;border:2px solid #000;box-shadow:4px 4px 0px rgba(0,0,0,0.3);display:block}
.split-content-block {flex:1 1 50%;display:flex;flex-direction:column;gap:1.25rem}
.split-badge {display:inline-block;font-size:0.8rem;font-weight:800;text-transform:uppercase;letter-spacing:0.1em;background-color:#2563eb;color:#fff;padding:0.2rem 0.6rem;border-radius:4px;width:fit-content}
.split-title {font-size:2rem;font-weight:800;margin:0;line-height:1.3}
.split-text {font-size:1.05rem;color:#cbd5e1;line-height:1.7;margin:0}
@media (max-width:700px){
  .split-section {padding:2rem 1.25rem}
  .split-inner {flex-direction:column;gap:2rem}
  .split-image-block {flex:1 1 auto;width:100%;max-width:320px;margin:0 auto}
  .split-content-block {flex:1 1 auto;width:100%;gap:1rem}
  .split-title {font-size:1.5rem}
  .split-text {font-size:0.95rem}
}