:root{
  --ink:#11172a;
  --text:#263454;
  --muted:#687593;
  --line:#dbe8f8;
  --blue:#2f70ff;
  --cyan:#32c6dd;
  --pink:#fb3c95;
  --violet:#7457f4;
  --surface:#fff;
  --soft:#f7fbff;
  --shadow:0 22px 60px rgba(72,117,176,.14);
}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{
  margin:0;
  background:linear-gradient(180deg,#f7fbff 0%,#fff 48%,#f8fbff 100%);
  color:var(--text);
  font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","Hiragino Kaku Gothic ProN","Yu Gothic",Meiryo,sans-serif;
  line-height:1.75;
  letter-spacing:0;
}
a{color:inherit}
img{max-width:100%}
.site-header{
  position:sticky;
  top:0;
  z-index:20;
  background:rgba(247,252,255,.9);
  border-bottom:1px solid rgba(125,207,234,.28);
  backdrop-filter:blur(18px);
  -webkit-backdrop-filter:blur(18px);
}
.header-inner{
  display:flex;
  align-items:center;
  justify-content:space-between;
  width:min(1160px,calc(100% - 36px));
  height:72px;
  margin:0 auto;
}
.brand{
  display:block;
  width:184px;
  height:44px;
  background:url("./assets/casta-logo.png") left center/contain no-repeat;
  text-indent:-9999px;
  overflow:hidden;
}
.nav{display:flex;align-items:center;gap:22px}
.nav a{
  color:#607096;
  font-size:14px;
  font-weight:800;
  text-decoration:none;
  white-space:nowrap;
}
.nav a:hover{color:#26305f}
.page{overflow:hidden}
.section{
  width:min(1160px,calc(100% - 36px));
  margin:0 auto;
  padding:72px 0;
}
.hero{
  display:grid;
  grid-template-columns:minmax(0,1fr) minmax(320px,500px);
  gap:44px;
  align-items:center;
  min-height:680px;
  padding-top:56px;
}
h1{
  margin:0;
  color:var(--ink);
  font-size:clamp(44px,6.2vw,84px);
  font-weight:950;
  line-height:1.04;
}
.gradient{
  background:linear-gradient(90deg,#335dff 0%,#8d43ef 52%,#fd3d9c 100%);
  -webkit-background-clip:text;
  background-clip:text;
  color:transparent;
}
.lead{
  max-width:690px;
  margin:24px 0 0;
  color:var(--muted);
  font-size:clamp(16px,1.45vw,19px);
  font-weight:760;
  line-height:1.95;
}
.hero-actions{display:flex;flex-wrap:wrap;align-items:center;gap:12px;margin-top:30px}
.app-store-badge{
  display:inline-flex;
  align-items:center;
  justify-content:center;
  width:224px;
  height:82px;
  text-decoration:none;
}
.app-store-badge img{display:block;width:224px;height:82px;object-fit:contain}
.ghost-btn,.primary-btn{
  display:inline-flex;
  align-items:center;
  justify-content:center;
  min-height:50px;
  padding:0 18px;
  border-radius:999px;
  font-size:14px;
  font-weight:950;
  text-decoration:none;
}
.primary-btn{
  background:linear-gradient(135deg,var(--blue),var(--violet),var(--pink));
  color:#fff;
  box-shadow:0 16px 34px rgba(98,88,243,.24);
}
.ghost-btn{border:1px solid rgba(125,207,234,.44);background:rgba(255,255,255,.86);color:#26305f}
.hero-visual{
  position:relative;
  min-height:560px;
}
.phone-frame{
  position:absolute;
  right:68px;
  top:0;
  width:min(70vw,335px);
  height:560px;
  overflow:hidden;
  border:1px solid rgba(125,207,234,.36);
  border-radius:34px;
  background:#fff;
  box-shadow:0 30px 88px rgba(88,138,188,.22);
  transform:rotate(2deg);
}
.phone-frame img{display:block;width:100%;height:100%;object-fit:cover;object-position:top center}
.profile-card{
  position:absolute;
  left:0;
  bottom:42px;
  width:min(88vw,330px);
  padding:18px;
  border:1px solid rgba(125,207,234,.42);
  border-radius:18px;
  background:rgba(255,255,255,.94);
  box-shadow:0 24px 64px rgba(88,138,188,.18);
}
.profile-url{
  display:inline-flex;
  align-items:center;
  min-height:32px;
  padding:0 11px;
  border-radius:999px;
  background:linear-gradient(135deg,rgba(47,112,255,.10),rgba(251,60,149,.10));
  color:#5148df;
  font-size:12px;
  font-weight:950;
}
.profile-card h2{margin:12px 0 5px;color:var(--ink);font-size:24px;line-height:1.25}
.profile-card p{margin:0;color:var(--muted);font-size:13px;font-weight:760;line-height:1.7}
.profile-links{display:grid;gap:8px;margin-top:14px}
.profile-links span{
  display:flex;
  justify-content:space-between;
  gap:12px;
  min-height:36px;
  padding:7px 10px;
  border:1px solid rgba(125,207,234,.25);
  border-radius:8px;
  background:#fff;
  color:#263454;
  font-size:13px;
  font-weight:900;
}
.section-head{display:flex;align-items:flex-end;justify-content:space-between;gap:20px;margin-bottom:18px}
.section-head h2{margin:0;color:#5148df;font-size:clamp(19px,1.8vw,26px);font-weight:950;letter-spacing:.06em}
.section-head p{max-width:520px;margin:0;color:var(--muted);font-size:14px;font-weight:760;line-height:1.8}
.feature-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:16px}
.feature{
  padding:22px;
  border:1px solid rgba(125,207,234,.30);
  border-radius:8px;
  background:rgba(255,255,255,.92);
  box-shadow:0 14px 38px rgba(88,138,188,.10);
}
.feature b{display:block;color:#172033;font-size:18px;font-weight:950;line-height:1.45}
.feature p{margin:10px 0 0;color:#647399;font-size:14px;font-weight:760;line-height:1.8}
.flow{
  display:grid;
  grid-template-columns:1fr 1fr;
  gap:18px;
  align-items:stretch;
}
.panel{
  padding:clamp(22px,4vw,34px);
  border:1px solid rgba(125,207,234,.28);
  border-radius:8px;
  background:linear-gradient(135deg,rgba(255,255,255,.96),rgba(247,252,255,.92));
  box-shadow:var(--shadow);
}
.panel h3{margin:0 0 12px;color:#172033;font-size:clamp(24px,2.8vw,38px);font-weight:950;line-height:1.25}
.panel p{margin:0;color:#647399;font-size:15px;font-weight:760;line-height:1.95}
.steps{display:grid;gap:10px;margin:22px 0 0;padding:0;list-style:none}
.steps li{display:grid;grid-template-columns:32px minmax(0,1fr);gap:12px;align-items:start;color:#263454;font-size:14px;font-weight:850}
.steps i{display:grid;place-items:center;width:32px;height:32px;border-radius:50%;background:linear-gradient(135deg,var(--blue),var(--pink));color:#fff;font-style:normal;font-size:13px;font-weight:950}
.preview-grid{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:14px}
.preview{
  overflow:hidden;
  border:1px solid rgba(125,207,234,.34);
  border-radius:20px;
  background:#fff;
  box-shadow:0 16px 42px rgba(88,138,188,.13);
}
.preview img{display:block;width:100%;height:auto}
.cta-band{
  display:grid;
  grid-template-columns:minmax(0,1fr) auto;
  gap:20px;
  align-items:center;
  padding:28px;
  border:1px solid rgba(125,207,234,.30);
  border-radius:12px;
  background:linear-gradient(135deg,#fff 0%,#f3f9ff 55%,#fff3fa 100%);
  box-shadow:var(--shadow);
}
.cta-band h2{margin:0;color:var(--ink);font-size:clamp(24px,3vw,42px);font-weight:950;line-height:1.2}
.cta-band p{margin:10px 0 0;color:var(--muted);font-size:15px;font-weight:760}
.site-footer{
  border-top:1px solid rgba(125,207,234,.25);
  background:#f8fbff;
}
.footer-inner{
  width:min(1160px,calc(100% - 36px));
  margin:0 auto;
  padding:28px 0;
  color:#647399;
  font-size:13px;
}
.footer-inner nav{display:flex;flex-wrap:wrap;gap:12px;margin-top:10px}
.footer-inner a{color:#5148df;font-weight:850;text-decoration:none}
.legal-page{width:min(920px,calc(100% - 36px));margin:0 auto;padding:54px 0 80px}
.legal-page h1{font-size:clamp(32px,5vw,54px)}
.legal-card{margin-top:22px;padding:clamp(22px,4vw,34px);border:1px solid rgba(125,207,234,.28);border-radius:12px;background:#fff;box-shadow:var(--shadow)}
.legal-card h2{margin:24px 0 8px;color:#172033;font-size:22px;line-height:1.4}
.legal-card h2:first-child{margin-top:0}
.legal-card p,.legal-card li{color:#4d5b78;font-size:15px;font-weight:700;line-height:1.9}
.legal-card ul{padding-left:1.2em}
@media(max-width:920px){
  .header-inner{justify-content:center;height:64px}
  .brand{width:178px;background-position:center}
  .nav{display:none}
  .section{width:min(100% - 28px,650px);padding:52px 0}
  .hero{grid-template-columns:1fr;min-height:0;padding-top:34px}
  .hero-visual{min-height:510px}
  .phone-frame{right:0;left:50%;transform:translateX(-48%) rotate(2deg);height:470px;width:min(78vw,320px)}
  .profile-card{left:0;bottom:6px}
  .feature-grid,.flow{grid-template-columns:1fr}
  .preview-grid{grid-template-columns:repeat(2,minmax(0,1fr))}
  .section-head{align-items:flex-start;flex-direction:column;gap:8px}
  .cta-band{grid-template-columns:1fr}
}
@media(max-width:560px){
  h1{font-size:42px}
  .lead{font-size:15px}
  .app-store-badge,.app-store-badge img{width:190px;height:70px}
  .phone-frame{height:430px}
  .profile-card{width:100%}
  .preview-grid{gap:10px}
  .cta-band{padding:22px}
}