/* ===== Sleep Calculator — base ===== */
:root{
  --bg:#0b1426;
  --bg-2:#101f38;
  --card:#16243f;
  --card-2:#1b2c4d;
  --text:#eaf0fb;
  --muted:#9db0cc;
  --brand:#8b80ff;
  --brand-2:#6d8bff;
  --accent:#f6c177;
  --success:#7fd1a1;
  --border:#243958;
  --radius:14px;
  --radius-sm:9px;
  --maxw:940px;
  --shadow:0 10px 30px rgba(0,0,0,.28);
}
*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth;-webkit-text-size-adjust:100%}
body{
  font:16px/1.65 "Inter",system-ui,-apple-system,"Segoe UI",Roboto,"Helvetica Neue",Arial,sans-serif;
  color:var(--text);
  background:
    radial-gradient(1200px 600px at 80% -10%,rgba(139,128,255,.18),transparent 60%),
    radial-gradient(900px 500px at -10% 10%,rgba(109,139,255,.14),transparent 55%),
    var(--bg);
  min-height:100vh;
  line-height:1.65;
}
a{color:var(--brand-2);text-decoration:none;transition:color .15s}
a:hover{color:var(--brand);text-decoration:underline}
img{max-width:100%;height:auto}
ul{padding-left:1.3em}

.wrap{max-width:var(--maxw);margin:0 auto;padding:0 20px}

/* header */
.site-header{position:sticky;top:0;z-index:30;backdrop-filter:blur(10px);background:rgba(11,20,38,.78);border-bottom:1px solid var(--border)}
.site-header .wrap{display:flex;align-items:center;justify-content:space-between;height:62px}
.brand{display:flex;align-items:center;gap:10px;font-weight:700;font-size:18px;color:var(--text)}
.brand:hover{text-decoration:none}
.brand .moon{width:22px;height:22px;border-radius:50%;background:radial-gradient(circle at 35% 30%,var(--accent),#caa15a 60%,transparent 61%),var(--bg-2);box-shadow:0 0 16px rgba(246,193,119,.5)}
.nav{display:flex;gap:22px}
.nav a{color:var(--muted);font-size:15px}
.nav a:hover{color:var(--text);text-decoration:none}

/* hero */
.hero{padding:54px 0 18px;text-align:center}
.hero h1{font-size:clamp(28px,5vw,44px);font-weight:800;letter-spacing:-.02em;line-height:1.15;margin-bottom:14px}
.hero p.lead{color:var(--muted);font-size:clamp(16px,2.4vw,19px);max-width:620px;margin:0 auto 8px}
.badge{display:inline-flex;align-items:center;gap:8px;background:rgba(139,128,255,.14);border:1px solid rgba(139,128,255,.4);color:#cfc9ff;font-size:13px;font-weight:600;padding:6px 14px;border-radius:999px;margin-bottom:18px}

/* calculator card */
.calc-card{background:linear-gradient(180deg,var(--card),var(--card-2));border:1px solid var(--border);border-radius:var(--radius);box-shadow:var(--shadow);padding:30px;margin:22px auto 8px;max-width:680px}
.tabs{display:flex;gap:8px;background:rgba(0,0,0,.22);border:1px solid var(--border);border-radius:999px;padding:5px;margin-bottom:24px}
.tab{flex:1;border:0;background:transparent;color:var(--muted);font:inherit;font-weight:600;font-size:14px;padding:11px 8px;border-radius:999px;cursor:pointer;transition:all .18s}
.tab.active{background:var(--brand);color:#0b1426;box-shadow:0 4px 14px rgba(139,128,255,.4)}
.tab:not(.active):hover{color:var(--text)}

.field{margin-bottom:22px}
.field label{display:block;font-size:14px;font-weight:600;color:var(--text);margin-bottom:8px}
.field .hint{font-size:13px;color:var(--muted);margin-top:6px}
.time-input{width:100%;background:rgba(0,0,0,.25);border:1px solid var(--border);color:var(--text);font:inherit;font-size:20px;font-weight:600;padding:14px 16px;border-radius:var(--radius-sm);text-align:center}
.time-input:focus{outline:none;border-color:var(--brand);box-shadow:0 0 0 3px rgba(139,128,255,.25)}
.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;width:100%;border:0;background:var(--brand);color:#0b1426;font:inherit;font-weight:700;font-size:16px;padding:15px;border-radius:var(--radius-sm);cursor:pointer;transition:transform .1s,box-shadow .2s}
.btn:hover{box-shadow:0 8px 24px rgba(139,128,255,.45)}
.btn:active{transform:translateY(1px)}

/* results */
.results{margin-top:26px;display:none}
.results.show{display:block;animation:fade .35s ease}
@keyframes fade{from{opacity:0;transform:translateY(8px)}to{opacity:1;transform:none}}
.results h2{font-size:17px;font-weight:700;margin-bottom:14px;color:var(--text)}
.result-list{display:grid;grid-template-columns:repeat(auto-fit,minmax(140px,1fr));gap:12px}
.result{background:rgba(0,0,0,.22);border:1px solid var(--border);border-radius:var(--radius-sm);padding:16px 14px;text-align:center;transition:border-color .15s,transform .12s}
.result:hover{border-color:var(--brand);transform:translateY(-2px)}
.result .t{font-size:26px;font-weight:800;color:var(--accent);letter-spacing:-.01em}
.result .t.now{color:var(--success)}
.result .lbl{font-size:13px;color:var(--muted);margin-top:6px}
.result.best{border-color:var(--accent);background:rgba(246,193,119,.1)}
.result.best .lbl{color:var(--accent);font-weight:600}
.note{font-size:13px;color:var(--muted);margin-top:16px;line-height:1.5}

/* content sections */
.section{padding:40px 0}
.section h2{font-size:clamp(22px,3.5vw,28px);font-weight:800;letter-spacing:-.01em;margin-bottom:14px}
.section p{color:#cfd8ea;margin:12px 0;max-width:680px}
.section .muted{color:var(--muted)}
.cards{display:grid;grid-template-columns:repeat(auto-fit,minmax(220px,1fr));gap:18px;margin-top:24px}
.card{background:var(--card);border:1px solid var(--border);border-radius:var(--radius);padding:22px}
.card h3{font-size:17px;font-weight:700;margin-bottom:8px;display:flex;gap:8px;align-items:center}
.card p{font-size:14px;color:var(--muted);margin:0}

/* article */
.article{padding:46px 0 30px}
.article h1{font-size:clamp(26px,4.5vw,36px);font-weight:800;letter-spacing:-.015em;margin-bottom:10px}
.article .meta{color:var(--muted);font-size:14px;margin-bottom:26px}
.article h2{font-size:clamp(20px,3vw,24px);font-weight:700;margin:30px 0 12px}
.article p{color:#cfd8ea;margin:14px 0}
.article ul{margin:14px 0;padding-left:1.3em}
.article li{margin:8px 0;color:#cfd8ea}
.article .lead-p{font-size:18px;color:var(--text)}
.prose{max-width:720px}

/* disclosure callout */
.callout{background:rgba(139,128,255,.08);border:1px solid rgba(139,128,255,.3);border-radius:var(--radius-sm);padding:16px 18px;font-size:14px;color:var(--muted);margin:26px 0}
.callout strong{color:#cfc9ff}

/* CTA strip */
.cta{margin:34px 0;padding:26px;background:linear-gradient(135deg,rgba(139,128,255,.16),rgba(109,139,255,.1));border:1px solid rgba(139,128,255,.35);border-radius:var(--radius)}
.cta h2{font-size:22px;margin-bottom:8px}
.cta p{color:var(--muted);margin:0}
.cta .btn{width:auto;margin-top:16px;padding:13px 26px}

/* footer */
.site-footer{border-top:1px solid var(--border);margin-top:40px;padding:34px 0 30px;color:var(--muted);font-size:14px}
.site-footer .cols{display:flex;flex-wrap:wrap;gap:30px;justify-content:space-between;margin-bottom:20px}
.site-footer .col h4{color:var(--text);font-size:14px;margin-bottom:10px}
.site-footer .col a{display:block;color:var(--muted);margin:7px 0}
.disclosure-mini{background:rgba(0,0,0,.2);border:1px solid var(--border);border-radius:var(--radius-sm);padding:14px 16px;font-size:12.5px;color:var(--muted);line-height:1.55}
.disclosure-mini a{color:var(--brand-2)}
.copyright{margin-top:18px;font-size:13px;opacity:.8;text-align:center}

/* responsive */
@media (max-width:640px){
  .nav{gap:14px}
  .nav a{font-size:14px}
  .calc-card{padding:22px 18px}
  .result .t{font-size:22px}
  .site-footer .cols{flex-direction:column;gap:18px}
}
.skip-link{position:absolute;left:-9999px}
.skip-link:focus{left:8px;top:8px;background:var(--brand);color:#0b1426;padding:8px 12px;border-radius:6px;z-index:50}