/* Global site styles — Apple-like aesthetic */
:root{
  --accent: #007aff; /* iOS blue */
  --accent-2: #34c759; /* green accent */
  --bg: rgba(242,244,247,1);
  --surface: rgba(255,255,255,0.85);
  --muted: #6b7280;
  --glass: rgba(255,255,255,0.6);
  --shadow: 0 8px 24px rgba(15,23,42,0.08);
}
*{box-sizing:border-box}
html,body{height:100%;margin:0;font-family:-apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans", system-ui; background:linear-gradient(180deg,var(--bg), #ffffff); color:#0f172a; -webkit-font-smoothing:antialiased; -moz-osx-font-smoothing:grayscale}
a{color:var(--accent); text-decoration:none}
.container-narrow{max-width:980px;margin:0 auto;padding:2rem}
.site-header{display:flex;align-items:center;justify-content:space-between;margin-bottom:1.25rem}
.site-title{font-weight:600;font-size:1.25rem;color:#0f172a}
.site-sub{color:var(--muted);font-size:.95rem}
.top-actions{display:flex;gap:.5rem}
.btn{display:inline-flex;align-items:center;justify-content:center;padding:.5rem .75rem;border-radius:12px;border:1px solid.transparent;font-weight:600;cursor:pointer}
.btn-outline-secondary{background:transparent;border-color:rgba(15,23,42,.06);color:var(--muted)}
.btn-primary{background:linear-gradient(180deg,var(--surface), #ffffff);color:var(--accent);border:none;border-radius:14px;box-shadow:var(--shadow);padding:.6rem .9rem}
.btn-primary:active{transform:translateY(1px)}
.card{background:var(--surface);backdrop-filter:blur(6px);-webkit-backdrop-filter:blur(6px);border-radius:14px;box-shadow:var(--shadow);padding:1.25rem;border:1px solid rgba(15,23,42,0.04)}
.log-meta{color:var(--muted)}
pre{background:#0f172a;color:#e6eef6;padding:1rem;border-radius:12px;overflow:auto}
/* Form and content */
.calc-container{display:flex;flex-direction:column;gap:1rem}
.input-lg{padding:.85rem 1rem;border-radius:12px;border:1px solid rgba(15,23,42,0.06);background:linear-gradient(180deg,#fff,#fbfdff)}
.result{padding:1rem;border-radius:12px;background:linear-gradient(180deg,#ffffff, #fbfdff);border:1px solid rgba(15,23,42,0.03)}

/* Navbar / header glass effect */
.navbar{background:var(--glass) !important; backdrop-filter: blur(8px); -webkit-backdrop-filter: blur(8px); border-bottom:1px solid rgba(15,23,42,0.04)}
.navbar .navbar-brand{font-weight:700}
.navbar .btn-outline-secondary{border-radius:10px}

/* Cards grid */
.card .card-title{font-weight:600}

/* Accessible focus */
:focus{outline:2px solid rgba(0,122,255,0.14);outline-offset:3px}

/* Responsive */
@media (max-width:640px){
  .container-narrow{padding:1rem}
  .site-title{font-size:1.05rem}
  .navbar .container-fluid { padding-left: .5rem; padding-right: .5rem }
  .card{border-radius:12px}
}

@media (min-width:1200px){
  .container-narrow{max-width:1100px}
}