:root {
  --bg: #eef3f6;
  --bg-tint: #e3edf2;
  --card: #ffffff;
  --ink: #0f1f2e;
  --muted: #5b6b7a;
  --line: #e4ebf1;
  --accent: #0d9488;        /* calm clinical teal */
  --accent-dark: #0b7d72;
  --accent-soft: #e6f5f3;
  --grad: linear-gradient(135deg, #14b8a6 0%, #0d9488 100%);
  --ok: #1f9d63;
  --ok-soft: #e6f6ee;
  --err: #d14343;
  --err-soft: #fcebeb;
  --radius: 18px;
  --radius-sm: 11px;
  --shadow: 0 1px 2px rgba(15, 31, 46, 0.04), 0 8px 24px rgba(15, 31, 46, 0.06);
  --shadow-lg: 0 10px 40px rgba(13, 148, 136, 0.18);
}

* { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  min-height: 100vh;
  color: var(--ink);
  background:
    radial-gradient(1100px 500px at 100% -10%, var(--accent-soft), transparent 55%),
    radial-gradient(900px 500px at -10% 110%, #e6eef7, transparent 55%),
    linear-gradient(180deg, var(--bg) 0%, var(--bg-tint) 100%);
  background-attachment: fixed;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica,
    Arial, "Apple Color Emoji", sans-serif;
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
}

/* --- Top bar --- */
.topbar {
  position: sticky;
  top: 0;
  z-index: 10;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 13px 20px;
  background: rgba(255, 255, 255, 0.75);
  backdrop-filter: saturate(180%) blur(14px);
  -webkit-backdrop-filter: saturate(180%) blur(14px);
  border-bottom: 1px solid var(--line);
}
.brand {
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--ink);
  text-decoration: none;
  font-size: 1.05rem;
  display: inline-flex;
  align-items: center;
  gap: 8px;
}
.brand::before {
  content: "";
  width: 22px; height: 22px;
  border-radius: 7px;
  background: var(--grad);
  box-shadow: var(--shadow-lg);
}
.topbar nav { display: flex; align-items: center; gap: 6px; }
.topbar nav a, .linkbtn {
  color: var(--muted);
  text-decoration: none;
  font-weight: 600;
  font-size: 0.92rem;
  padding: 7px 12px;
  border-radius: 9px;
  transition: background 0.15s, color 0.15s;
}
.topbar nav a:hover, .linkbtn:hover { background: var(--accent-soft); color: var(--accent-dark); }
.inline { margin: 0; display: inline; }
.linkbtn { background: none; border: none; cursor: pointer; font-family: inherit; }

/* --- Layout --- */
.container { max-width: 580px; margin: 0 auto; padding: 30px 18px 70px; }

h1 { font-size: 1.7rem; letter-spacing: -0.03em; margin: 0 0 6px; }
h2 { font-size: 1.05rem; letter-spacing: -0.01em; margin: 0 0 12px; }
.muted { color: var(--muted); }
.small { font-size: 0.85rem; }
.error { background: var(--err-soft); color: var(--err); font-weight: 600;
  padding: 11px 14px; border-radius: var(--radius-sm); margin: 0 0 16px; }
.success { background: var(--ok-soft); color: var(--ok); font-weight: 600;
  padding: 11px 14px; border-radius: var(--radius-sm); margin: 0 0 16px; }

.card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 22px;
  margin: 18px 0;
  box-shadow: var(--shadow);
}

/* --- Forms --- */
label { display: block; margin: 0 0 16px; font-weight: 600; font-size: 0.9rem;
  color: #2a3a48; }
input, textarea {
  display: block;
  width: 100%;
  margin-top: 7px;
  padding: 13px 14px;
  font: inherit;
  font-weight: 400;
  color: var(--ink);
  border: 1.5px solid var(--line);
  border-radius: var(--radius-sm);
  background: #fbfdfe;
  transition: border-color 0.15s, box-shadow 0.15s, background 0.15s;
}
input:focus, textarea:focus {
  outline: none;
  background: #fff;
  border-color: var(--accent);
  box-shadow: 0 0 0 4px rgba(13, 148, 136, 0.14);
}
input::placeholder, textarea::placeholder { color: #9aa8b4; }

/* --- Buttons --- */
.btn, .btn-secondary {
  display: inline-block;
  border: none;
  border-radius: var(--radius-sm);
  padding: 13px 20px;
  font: inherit;
  font-weight: 650;
  cursor: pointer;
  text-decoration: none;
  text-align: center;
  transition: transform 0.08s, box-shadow 0.15s, background 0.15s;
}
.btn {
  background: var(--grad);
  color: #fff;
  width: 100%;
  box-shadow: var(--shadow-lg);
}
.btn:hover { transform: translateY(-1px); }
.btn:active { transform: translateY(0); }
.btn-secondary {
  background: #fff;
  color: var(--accent-dark);
  border: 1.5px solid var(--line);
  box-shadow: var(--shadow);
}
.btn-secondary:hover { border-color: var(--accent); background: var(--accent-soft); }

/* --- Lists --- */
.list { list-style: none; padding: 0; margin: 0; }
.list li {
  display: flex; justify-content: space-between; align-items: center; gap: 12px;
  padding: 13px 0; border-bottom: 1px solid var(--line);
}
.list li:last-child { border-bottom: none; }
.list li span { font-weight: 600; }

/* --- Diary: Fitbit connect card --- */
.fitbit-card { padding: 16px 18px; }
.fitbit-row { display: flex; align-items: center; justify-content: space-between; gap: 14px; }
.fitbit-row .btn-secondary { padding: 9px 16px; white-space: nowrap; }
.fb-tag {
  display: inline-block; font-size: 0.7rem; font-weight: 700;
  color: var(--accent-dark); background: var(--accent-soft);
  padding: 2px 8px; border-radius: 999px; margin-left: 6px; vertical-align: middle;
}

/* --- Dashboard: one-tap quick-log (your main sensor) --- */
.quicklog { margin: 18px 0 4px; }
.btn-quicklog {
  display: flex; flex-direction: column; align-items: center; gap: 2px;
  width: 100%; padding: 24px; border: none; cursor: pointer;
  border-radius: 20px; color: #fff; background: var(--grad);
  box-shadow: 0 12px 34px rgba(13, 148, 136, 0.32);
  transition: transform 0.1s, box-shadow 0.2s;
}
.btn-quicklog:hover { box-shadow: 0 16px 42px rgba(13, 148, 136, 0.42); }
.btn-quicklog:active { transform: scale(0.985); }
.ql-action { font-size: 1.4rem; font-weight: 750; letter-spacing: -0.01em; }
.ql-sensor { font-size: 0.95rem; font-weight: 600; opacity: 0.9; }
.ql-hint { text-align: center; margin: 10px 0 0; }

/* --- Dashboard: stat cards --- */
.stat-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 12px; margin: 18px 0; }
.stat {
  background: var(--card); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 16px 12px; text-align: center;
  box-shadow: var(--shadow);
}
.stat-num {
  font-size: 1.9rem; font-weight: 750; letter-spacing: -0.03em; line-height: 1.1;
  background: var(--grad); -webkit-background-clip: text; background-clip: text;
  -webkit-text-fill-color: transparent;
}
.stat-label { font-size: 0.74rem; color: var(--muted); font-weight: 600;
  text-transform: uppercase; letter-spacing: 0.04em; margin-top: 4px; }

/* --- Dashboard: 14-day bar chart --- */
.chart { display: flex; align-items: flex-end; gap: 5px; height: 140px; padding-top: 16px; }
.chart-col { flex: 1; display: flex; flex-direction: column; align-items: center; height: 100%; }
.chart-bar-wrap {
  flex: 1; width: 100%; display: flex; flex-direction: column;
  align-items: center; justify-content: flex-end; position: relative;
}
.chart-bar {
  width: 78%; min-height: 3px; border-radius: 6px 6px 3px 3px;
  background: var(--grad); transition: height 0.4s ease;
}
.chart-count { font-size: 0.66rem; font-weight: 700; color: var(--accent-dark); margin-bottom: 3px; min-height: 0.9em; }
.chart-x { font-size: 0.62rem; color: var(--muted); margin-top: 5px; }

/* --- Dashboard: diary averages --- */
.avg-row { display: grid; grid-template-columns: repeat(3, 1fr); gap: 12px; text-align: center; }
.avg span {
  display: block; font-size: 1.6rem; font-weight: 750; letter-spacing: -0.02em;
  color: var(--accent-dark);
}
.avg label { font-size: 0.78rem; color: var(--muted); font-weight: 600; margin: 0; }

/* --- The one-click visit screen (most important) --- */
.visit-screen { text-align: center; padding-top: 26px; animation: rise 0.4s ease; }
@keyframes rise { from { opacity: 0; transform: translateY(10px); } to { opacity: 1; transform: none; } }
.visit-screen .card { text-align: left; }
.sensor-name {
  font-size: 2.1rem; letter-spacing: -0.03em; margin: 6px 0 30px;
  background: var(--grad); -webkit-background-clip: text; background-clip: text;
  -webkit-text-fill-color: transparent;
}
.btn-huge {
  display: block;
  width: 100%;
  padding: 34px 24px;
  font-size: 1.55rem;
  font-weight: 750;
  letter-spacing: -0.01em;
  color: #fff;
  background: var(--grad);
  border: none;
  border-radius: 22px;
  cursor: pointer;
  box-shadow: 0 12px 34px rgba(13, 148, 136, 0.34);
  transition: transform 0.1s, box-shadow 0.2s;
}
.btn-huge:hover { box-shadow: 0 16px 42px rgba(13, 148, 136, 0.42); }
.btn-huge:active { transform: scale(0.985); }
.checkmark {
  width: 96px; height: 96px; line-height: 96px;
  margin: 14px auto 20px;
  font-size: 3.1rem; color: #fff; background: var(--grad);
  border-radius: 50%;
  box-shadow: var(--shadow-lg);
  animation: pop 0.45s cubic-bezier(.2,.8,.2,1.2);
}
@keyframes pop { 0% { transform: scale(0); } 70% { transform: scale(1.08); } 100% { transform: scale(1); } }

/* --- QR sheet --- */
.qr-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 18px; }
.qr-item {
  margin: 0; text-align: center;
  background: var(--card); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 16px;
  box-shadow: var(--shadow);
}
.qr-item img { width: 100%; height: auto; max-width: 220px; border-radius: 10px; }

@media print {
  body { background: #fff; }
  .topbar, .no-print { display: none; }
  .qr-item { border: 1px solid #000; box-shadow: none; break-inside: avoid; }
}