/* =========================================================
   SleepSync — styles.css
   Minimal, professional design with Apple-glass surfaces.
   ========================================================= */

/* ---------- Design tokens (light) ---------- */
:root {
  --bg:           #FAFAF7;
  --bg-2:         #F2F2EE;
  --surface:      #FFFFFF;
  --surface-2:    #F4F4EF;
  --ink:          #0A0A0A;
  --ink-muted:    #525252;
  --ink-subtle:   #8A8A85;
  --border:       #E6E6E0;
  --border-strong:#D4D4CC;
  --accent:       #4F46E5;     /* indigo, used sparingly */
  --accent-2:     #7C3AED;     /* purple companion */
  --accent-3:     #06B6D4;     /* teal companion */
  --accent-soft:  #EEF0FF;
  --good:         #15803D;
  --warn:         #B45309;
  --bad:          #B91C1C;

  --radius-sm:    8px;
  --radius:       14px;
  --radius-lg:    20px;
  --radius-xl:    28px;

  --maxw:         1180px;

  /* Glass tokens */
  --glass-bg:        rgba(255, 255, 255, 0.55);
  --glass-bg-strong: rgba(255, 255, 255, 0.72);
  --glass-border:    rgba(255, 255, 255, 0.55);
  --glass-inner:     rgba(255, 255, 255, 0.65);
  --glass-blur:      18px;
}

/* ---------- Dark mode ---------- */
html.dark {
  --bg:           #07070A;
  --bg-2:         #0B0B11;
  --surface:      #131318;
  --surface-2:    #1A1A20;
  --ink:          #F5F5F4;
  --ink-muted:    #A3A3A0;
  --ink-subtle:   #707074;
  --border:       #1F1F23;
  --border-strong:#2A2A30;
  --accent:       #818CF8;
  --accent-2:     #A78BFA;
  --accent-3:     #22D3EE;
  --accent-soft:  #1E1E2E;
  --good:         #4ADE80;
  --warn:         #FCD34D;
  --bad:          #FCA5A5;

  --glass-bg:        rgba(22, 22, 30, 0.55);
  --glass-bg-strong: rgba(22, 22, 30, 0.72);
  --glass-border:    rgba(255, 255, 255, 0.10);
  --glass-inner:     rgba(255, 255, 255, 0.06);
}

/* ---------- Base ---------- */
* { box-sizing: border-box; }
html, body {
  background: var(--bg);
  color: var(--ink);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
  transition: background-color .25s ease, color .25s ease;
}
body {
  font-family: 'Inter', system-ui, -apple-system, sans-serif;
  font-size: 15px;
  line-height: 1.55;
  margin: 0;
  min-height: 100vh;
  position: relative;
  overflow-x: hidden;
}
::selection { background: var(--accent); color: #fff; }

/* ---------- Aurora background ---------- */
.bg-aurora {
  position: fixed;
  inset: 0;
  z-index: -1;
  overflow: hidden;
  pointer-events: none;
  background: var(--bg);
}
.aurora {
  position: absolute;
  border-radius: 50%;
  filter: blur(80px);
  opacity: 0.55;
  will-change: transform;
}
.aurora.a1 {
  width: 720px; height: 720px;
  background: radial-gradient(circle, #C7D2FE 0%, transparent 60%);
  top: -250px; right: -180px;
  animation: drift1 22s ease-in-out infinite alternate;
}
.aurora.a2 {
  width: 640px; height: 640px;
  background: radial-gradient(circle, #DDD6FE 0%, transparent 60%);
  top: 30vh; left: -200px;
  animation: drift2 28s ease-in-out infinite alternate;
}
.aurora.a3 {
  width: 540px; height: 540px;
  background: radial-gradient(circle, #FDE68A 0%, transparent 60%);
  top: 65vh; right: 10vw;
  opacity: 0.35;
  animation: drift3 32s ease-in-out infinite alternate;
}
html.dark .aurora { opacity: 0.32; mix-blend-mode: screen; }
html.dark .aurora.a1 { background: radial-gradient(circle, #4338CA 0%, transparent 60%); }
html.dark .aurora.a2 { background: radial-gradient(circle, #7C3AED 0%, transparent 60%); }
html.dark .aurora.a3 { background: radial-gradient(circle, #0EA5E9 0%, transparent 60%); }

@keyframes drift1 { from { transform: translate(0,0) scale(1); } to { transform: translate(-60px, 40px) scale(1.08); } }
@keyframes drift2 { from { transform: translate(0,0) scale(1); } to { transform: translate(50px, -30px) scale(1.06); } }
@keyframes drift3 { from { transform: translate(0,0) scale(1); } to { transform: translate(-30px, -50px) scale(1.05); } }

/* ---------- Typography ---------- */
.font-display {
  font-family: 'Plus Jakarta Sans', 'Inter', system-ui, sans-serif;
  letter-spacing: -0.02em;
}
.font-mono {
  font-family: 'JetBrains Mono', ui-monospace, SFMono-Regular, monospace;
  font-variant-numeric: tabular-nums;
}
.font-numeric {
  font-family: 'Sora', 'Plus Jakarta Sans', system-ui, sans-serif;
  font-variant-numeric: tabular-nums;
  font-feature-settings: 'tnum' 1;
}

.eyebrow {
  font-size: 11px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--ink-subtle);
  font-weight: 600;
}
.muted   { color: var(--ink-muted); }
.subtle  { color: var(--ink-subtle); }

/* ---------- Layout ---------- */
.container {
  width: 100%;
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 0 24px;
}
@media (min-width: 768px) { .container { padding: 0 40px; } }

.divider { height: 1px; background: var(--border); }

/* ---------- Glass surface (Apple-style) ---------- */
.glass-card {
  background: var(--glass-bg);
  border: 1px solid var(--glass-border);
  -webkit-backdrop-filter: blur(var(--glass-blur)) saturate(180%);
  backdrop-filter: blur(var(--glass-blur)) saturate(180%);
  box-shadow:
    inset 0 1px 0 var(--glass-inner),
    inset 0 -1px 0 rgba(0,0,0,0.04),
    0 1px 3px rgba(10,10,10,0.04),
    0 8px 24px -6px rgba(10,10,10,0.10),
    0 28px 64px -16px rgba(10,10,10,0.10);
  position: relative;
}
html.dark .glass-card {
  box-shadow:
    inset 0 1px 0 rgba(255,255,255,0.08),
    inset 0 -1px 0 rgba(0,0,0,0.3),
    0 1px 3px rgba(0,0,0,0.5),
    0 12px 32px -6px rgba(0,0,0,0.55),
    0 32px 80px -20px rgba(0,0,0,0.6);
}

.glass-chip {
  background: var(--glass-bg-strong);
  border: 1px solid var(--glass-border);
  -webkit-backdrop-filter: blur(14px) saturate(180%);
  backdrop-filter: blur(14px) saturate(180%);
  box-shadow:
    inset 0 1px 0 var(--glass-inner),
    0 1px 2px rgba(10,10,10,0.04),
    0 6px 16px -4px rgba(10,10,10,0.06);
}
html.dark .glass-chip {
  box-shadow:
    inset 0 1px 0 rgba(255,255,255,0.08),
    0 1px 2px rgba(0,0,0,0.4),
    0 6px 16px -4px rgba(0,0,0,0.4);
}

/* ---------- Header ---------- */
.site-header {
  position: sticky; top: 0; z-index: 30;
  border-bottom: 1px solid var(--glass-border);
  background: var(--glass-bg);
  -webkit-backdrop-filter: blur(20px) saturate(180%);
  backdrop-filter: blur(20px) saturate(180%);
  box-shadow: 0 1px 0 var(--glass-inner) inset, 0 1px 2px rgba(10,10,10,0.03);
}
.site-header .nav {
  display: flex; align-items: center; justify-content: space-between;
  padding: 16px 0;
}
.brand {
  display: inline-flex; align-items: center; gap: 10px;
  text-decoration: none; color: var(--ink);
  font-family: 'Plus Jakarta Sans', sans-serif;
  font-weight: 700;
  letter-spacing: -0.01em;
  font-size: 17px;
}
.brand-accent {
  background: linear-gradient(135deg, var(--accent) 0%, var(--accent-2) 100%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}
.brand-mark {
  width: 32px; height: 32px;
  border-radius: 10px;
  background: linear-gradient(180deg, #1a1a1a 0%, #000 100%);
  color: var(--bg);
  display: inline-flex; align-items: center; justify-content: center;
  box-shadow:
    inset 0 1px 0 rgba(255,255,255,0.18),
    0 1px 2px rgba(10,10,10,0.18),
    0 6px 14px -4px rgba(10,10,10,0.28);
}
html.dark .brand-mark {
  background: linear-gradient(180deg, #f5f5f4 0%, #c8c8c4 100%);
  box-shadow:
    inset 0 1px 0 rgba(255,255,255,0.5),
    0 1px 2px rgba(0,0,0,0.5),
    0 6px 14px -4px rgba(0,0,0,0.5);
}
.brand-mark svg { width: 16px; height: 16px; }

.nav-links {
  display: none; gap: 28px; font-size: 14px;
  color: var(--ink-muted);
}
.nav-links a { color: inherit; text-decoration: none; transition: color .15s; }
.nav-links a:hover { color: var(--ink); }
@media (min-width: 768px) { .nav-links { display: inline-flex; } }

.icon-btn {
  width: 38px; height: 38px;
  display: inline-flex; align-items: center; justify-content: center;
  background: var(--glass-bg-strong);
  color: var(--ink);
  border: 1px solid var(--glass-border);
  border-radius: 11px;
  cursor: pointer;
  -webkit-backdrop-filter: blur(10px);
  backdrop-filter: blur(10px);
  transition: transform .18s ease, box-shadow .18s ease;
  box-shadow:
    inset 0 1px 0 var(--glass-inner),
    0 1px 2px rgba(10,10,10,0.05),
    0 4px 10px -2px rgba(10,10,10,0.08);
}
.icon-btn:hover { transform: translateY(-1px); box-shadow:
    inset 0 1px 0 var(--glass-inner),
    0 2px 4px rgba(10,10,10,0.06),
    0 8px 18px -4px rgba(10,10,10,0.12);
}
.icon-btn svg { width: 16px; height: 16px; }

/* ---------- Section spacing ---------- */
section { padding: 56px 0; }
@media (min-width: 768px) { section { padding: 80px 0; } }

/* ---------- Calculator hero ---------- */
.calc-section { padding-top: 48px; padding-bottom: 64px; }
@media (min-width: 768px) { .calc-section { padding-top: 64px; padding-bottom: 96px; } }

.hero-row {
  display: grid;
  grid-template-columns: 1fr;
  gap: 28px;
  align-items: center;
}
@media (min-width: 900px) { .hero-row { grid-template-columns: 1.5fr 1fr; gap: 40px; } }

.calc-eyebrow { display: inline-flex; align-items: center; gap: 8px; }
.live-dot {
  width: 6px; height: 6px; border-radius: 50%;
  background: var(--good);
  position: relative; display: inline-block;
}
.live-dot::after {
  content: ''; position: absolute; inset: -4px;
  border-radius: 50%; background: var(--good);
  opacity: 0.25; animation: pulseLive 2s ease-in-out infinite;
}
@keyframes pulseLive {
  0%,100% { transform: scale(1);   opacity: 0.25; }
  50%     { transform: scale(1.6); opacity: 0;    }
}

h1.headline {
  margin: 16px 0 14px;
  font-family: 'Plus Jakarta Sans', sans-serif;
  font-weight: 700;
  font-size: clamp(36px, 6vw, 60px);
  line-height: 1.04;
  letter-spacing: -0.035em;
  color: var(--ink);
}
h1.headline em {
  font-style: normal;
  background: linear-gradient(135deg, var(--accent) 0%, var(--accent-2) 100%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}
.lede {
  max-width: 560px;
  font-size: clamp(15px, 1.6vw, 16px);
  line-height: 1.6;
  color: var(--ink-muted);
}

/* ---------- Glass orb ---------- */
.orb-wrap {
  position: relative;
  display: flex; justify-content: center; align-items: center;
  height: 280px;
  perspective: 900px;
  margin: 0 auto;
}
@media (min-width: 900px) { .orb-wrap { height: 320px; } }

.orb-shadow {
  position: absolute;
  bottom: 16px;
  width: 60%; height: 30px;
  background: radial-gradient(ellipse at center, rgba(79,70,229,0.32), transparent 70%);
  filter: blur(16px);
  z-index: 0;
}
html.dark .orb-shadow {
  background: radial-gradient(ellipse at center, rgba(124,58,237,0.45), transparent 70%);
}

.glass-orb {
  position: relative;
  width: 240px; height: 240px;
  border-radius: 50%;
  display: flex; align-items: center; justify-content: center;
  z-index: 1;
  background:
    radial-gradient(circle at 30% 25%,
      rgba(255,255,255,0.95) 0%,
      rgba(221,213,253,0.55) 22%,
      rgba(167,139,250,0.55) 45%,
      rgba(99,102,241,0.65) 70%,
      rgba(30,27,75,0.85) 100%);
  box-shadow:
    inset 0 0 50px rgba(255,255,255,0.25),
    inset -30px -40px 70px rgba(15,15,40,0.45),
    inset 8px 8px 30px rgba(255,255,255,0.4),
    0 30px 70px -10px rgba(99,102,241,0.45),
    0 12px 30px -8px rgba(124,58,237,0.35),
    0 0 0 1px rgba(255,255,255,0.18);
  transform-style: preserve-3d;
  transition: transform .35s cubic-bezier(.2,.7,.2,1);
  will-change: transform;
  cursor: grab;
  animation: orbBreathe 6s ease-in-out infinite;
}
@keyframes orbBreathe {
  0%,100% { box-shadow:
    inset 0 0 50px rgba(255,255,255,0.25),
    inset -30px -40px 70px rgba(15,15,40,0.45),
    inset 8px 8px 30px rgba(255,255,255,0.4),
    0 30px 70px -10px rgba(99,102,241,0.45),
    0 12px 30px -8px rgba(124,58,237,0.35),
    0 0 0 1px rgba(255,255,255,0.18); }
  50%     { box-shadow:
    inset 0 0 50px rgba(255,255,255,0.30),
    inset -30px -40px 70px rgba(15,15,40,0.40),
    inset 8px 8px 30px rgba(255,255,255,0.45),
    0 36px 90px -10px rgba(99,102,241,0.55),
    0 12px 30px -8px rgba(124,58,237,0.40),
    0 0 0 1px rgba(255,255,255,0.22); }
}
html.dark .glass-orb {
  background:
    radial-gradient(circle at 30% 25%,
      rgba(255,255,255,0.55) 0%,
      rgba(167,139,250,0.45) 25%,
      rgba(99,102,241,0.55) 50%,
      rgba(30,27,75,0.85) 75%,
      rgba(8,8,16,1) 100%);
}

/* Specular highlight (top-left bright spot) */
.orb-shine {
  position: absolute;
  top: 8%; left: 12%;
  width: 38%; height: 30%;
  background: radial-gradient(ellipse at 35% 30%,
    rgba(255,255,255,0.95) 0%,
    rgba(255,255,255,0.6) 30%,
    rgba(255,255,255,0) 70%);
  border-radius: 50%;
  filter: blur(2px);
  pointer-events: none;
  transform: rotate(-15deg);
}
/* Bottom rim glow */
.orb-rim {
  position: absolute;
  bottom: 10%; left: 22%; right: 22%; height: 12%;
  background: radial-gradient(ellipse at center,
    rgba(167,139,250,0.55) 0%,
    rgba(167,139,250,0) 70%);
  border-radius: 50%;
  filter: blur(6px);
  pointer-events: none;
}

.orb-content {
  position: relative;
  z-index: 2;
  text-align: center;
  color: white;
  text-shadow: 0 2px 8px rgba(0,0,0,0.3);
  pointer-events: none;
}
.orb-eyebrow {
  font-size: 10px;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  font-weight: 600;
  opacity: 0.85;
}
.orb-duration {
  font-family: 'Sora', sans-serif;
  font-weight: 700;
  font-size: 36px;
  letter-spacing: -0.03em;
  line-height: 1;
  margin: 8px 0 6px;
  font-variant-numeric: tabular-nums;
}
.orb-meta {
  font-size: 11px;
  opacity: 0.85;
  letter-spacing: 0.04em;
}

/* ---------- Calculator card ---------- */
.calc-card {
  margin-top: 28px;
  border-radius: var(--radius-xl);
  overflow: hidden;
  position: relative;
  transition: box-shadow .35s ease, transform .35s cubic-bezier(.2,.7,.2,1);
}
.calc-card::before {
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: 120px;
  background: linear-gradient(180deg, rgba(255,255,255,0.4), rgba(255,255,255,0));
  pointer-events: none;
  opacity: 0.5;
}
html.dark .calc-card::before {
  background: linear-gradient(180deg, rgba(255,255,255,0.04), rgba(255,255,255,0));
}

.calc-card-header {
  padding: 22px 28px;
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
}
@media (max-width: 600px) { .calc-card-header { padding: 18px 20px; } }

/* Segmented control (Apple-style pills) */
.seg {
  display: inline-flex;
  background: var(--surface-2);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 4px;
  flex-wrap: wrap;
  box-shadow: inset 0 1px 2px rgba(10,10,10,0.04);
}
html.dark .seg { box-shadow: inset 0 1px 2px rgba(0,0,0,0.4); }
.seg-btn {
  border: 0;
  background: transparent;
  padding: 8px 14px;
  font-size: 13px;
  font-weight: 600;
  color: var(--ink-muted);
  border-radius: 8px;
  cursor: pointer;
  transition: background-color .18s, color .18s, box-shadow .18s, transform .18s;
  font-family: inherit;
  white-space: nowrap;
}
.seg-btn:hover { color: var(--ink); }
.seg-btn.active {
  background: var(--surface);
  color: var(--ink);
  box-shadow:
    inset 0 1px 0 rgba(255,255,255,0.6),
    0 1px 2px rgba(10,10,10,0.05),
    0 4px 10px -3px rgba(10,10,10,0.10);
}
html.dark .seg-btn.active {
  background: var(--surface-2);
  box-shadow:
    inset 0 1px 0 rgba(255,255,255,0.06),
    0 1px 2px rgba(0,0,0,0.5),
    0 4px 10px -3px rgba(0,0,0,0.6);
}

/* Calculator body grid */
.calc-body {
  display: grid;
  grid-template-columns: 1fr;
  gap: 0;
}
@media (min-width: 900px) { .calc-body { grid-template-columns: 1.05fr 1.4fr; } }

.calc-input-pane {
  padding: 28px;
  border-bottom: 1px solid var(--border);
}
.calc-results-pane {
  padding: 28px;
  background: rgba(244,244,239,0.55);
  -webkit-backdrop-filter: blur(8px);
  backdrop-filter: blur(8px);
}
html.dark .calc-results-pane { background: rgba(13,13,18,0.55); }
@media (min-width: 900px) {
  .calc-input-pane { border-right: 1px solid var(--border); border-bottom: 0; }
}
@media (max-width: 600px) {
  .calc-input-pane, .calc-results-pane { padding: 22px; }
}

.field-label {
  display: block;
  font-size: 11px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--ink-subtle);
  margin-bottom: 12px;
  font-weight: 600;
}

/* Time input — "display screen" with depth */
.time-input-row {
  display: flex; align-items: center; gap: 12px;
  background: var(--surface-2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 18px 22px;
  box-shadow:
    inset 0 1px 3px rgba(10,10,10,0.06),
    inset 0 -1px 0 rgba(255,255,255,0.5),
    0 1px 0 rgba(255,255,255,0.6);
}
html.dark .time-input-row {
  box-shadow:
    inset 0 1px 3px rgba(0,0,0,0.5),
    inset 0 -1px 0 rgba(255,255,255,0.04),
    0 1px 0 rgba(255,255,255,0.04);
}
.time-input {
  flex: 1;
  font-family: 'Sora', 'Plus Jakarta Sans', sans-serif;
  font-feature-settings: 'tnum' 1;
  font-variant-numeric: tabular-nums;
  font-size: clamp(34px, 5.2vw, 50px);
  font-weight: 700;
  letter-spacing: -0.03em;
  color: var(--ink);
  background: transparent;
  border: 0;
  padding: 0;
  width: 100%;
  outline: none;
  caret-color: var(--accent);
}
.time-input:disabled { opacity: 0.55; cursor: not-allowed; }

.now-pill {
  display: inline-flex; align-items: center; gap: 6px;
  padding: 6px 10px;
  font-family: 'JetBrains Mono', monospace;
  font-size: 11px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 999px;
  color: var(--ink-muted);
  white-space: nowrap;
  box-shadow:
    inset 0 1px 0 rgba(255,255,255,0.6),
    0 1px 2px rgba(10,10,10,0.04);
}
html.dark .now-pill {
  background: var(--surface-2);
  box-shadow: inset 0 1px 0 rgba(255,255,255,0.06), 0 1px 2px rgba(0,0,0,0.4);
}

/* Preset chips */
.preset-row {
  margin-top: 22px;
  display: flex; flex-wrap: wrap; gap: 8px;
}
.preset {
  border: 1px solid var(--border);
  background: var(--surface);
  color: var(--ink-muted);
  padding: 7px 13px;
  border-radius: 999px;
  font-size: 12px;
  font-weight: 500;
  font-family: inherit;
  cursor: pointer;
  transition: border-color .15s, color .15s, transform .15s, box-shadow .15s;
  box-shadow:
    inset 0 1px 0 rgba(255,255,255,0.6),
    0 1px 2px rgba(10,10,10,0.04);
}
html.dark .preset {
  background: var(--surface-2);
  box-shadow: inset 0 1px 0 rgba(255,255,255,0.04), 0 1px 2px rgba(0,0,0,0.3);
}
.preset:hover {
  border-color: var(--ink);
  color: var(--ink);
  transform: translateY(-1px);
  box-shadow:
    inset 0 1px 0 rgba(255,255,255,0.7),
    0 4px 10px -2px rgba(10,10,10,0.08);
}

/* Slider */
.slider-row { margin-top: 28px; }
.slider-row .slider-head {
  display: flex; align-items: baseline; justify-content: space-between;
  margin-bottom: 10px;
}
.slider-row .slider-val {
  font-family: 'Sora', sans-serif;
  font-size: 14px;
  color: var(--ink);
  font-weight: 700;
  font-variant-numeric: tabular-nums;
}
input[type="range"] {
  appearance: none; -webkit-appearance: none;
  width: 100%; height: 4px;
  background: var(--border);
  border-radius: 999px;
  outline: none;
  box-shadow: inset 0 1px 2px rgba(10,10,10,0.06);
}
html.dark input[type="range"] { box-shadow: inset 0 1px 2px rgba(0,0,0,0.4); }
input[type="range"]::-webkit-slider-thumb {
  appearance: none; -webkit-appearance: none;
  width: 22px; height: 22px;
  background: linear-gradient(180deg, #1a1a1a 0%, #000 100%);
  border: 2px solid var(--surface);
  border-radius: 50%; cursor: grab;
  box-shadow:
    inset 0 1px 0 rgba(255,255,255,0.18),
    0 2px 4px rgba(10,10,10,0.18),
    0 6px 14px -3px rgba(10,10,10,0.25);
  transition: transform .15s ease, box-shadow .15s ease;
}
html.dark input[type="range"]::-webkit-slider-thumb {
  background: linear-gradient(180deg, #f5f5f4 0%, #c8c8c4 100%);
  box-shadow:
    inset 0 1px 0 rgba(255,255,255,0.5),
    0 2px 4px rgba(0,0,0,0.5),
    0 6px 14px -3px rgba(0,0,0,0.55);
}
input[type="range"]::-webkit-slider-thumb:hover  { transform: scale(1.1); }
input[type="range"]::-webkit-slider-thumb:active { cursor: grabbing; transform: scale(1.05); }
input[type="range"]::-moz-range-thumb {
  width: 22px; height: 22px;
  background: var(--ink); border: 2px solid var(--surface);
  border-radius: 50%; cursor: grab;
  box-shadow: 0 2px 4px rgba(10,10,10,0.18);
}

/* ---------- Age section ---------- */
.age-row {
  margin-top: 28px;
  display: grid;
  grid-template-columns: 1fr;
  gap: 14px;
}
@media (min-width: 600px) { .age-row { grid-template-columns: 0.85fr 1.15fr; align-items: stretch; } }

.age-input-block {
  display: flex; flex-direction: column;
}
.age-input-wrap {
  display: flex; align-items: baseline; gap: 8px;
  background: var(--surface-2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 14px 18px;
  box-shadow:
    inset 0 1px 3px rgba(10,10,10,0.05),
    0 1px 0 rgba(255,255,255,0.6);
}
html.dark .age-input-wrap {
  box-shadow:
    inset 0 1px 3px rgba(0,0,0,0.45),
    0 1px 0 rgba(255,255,255,0.04);
}
.age-input {
  font-family: 'Sora', 'Plus Jakarta Sans', sans-serif;
  font-feature-settings: 'tnum' 1;
  font-variant-numeric: tabular-nums;
  font-weight: 700;
  font-size: 28px;
  letter-spacing: -0.025em;
  color: var(--ink);
  background: transparent;
  border: 0;
  padding: 0;
  width: 80px;
  outline: none;
  caret-color: var(--accent);
  -moz-appearance: textfield;
}
.age-input::-webkit-outer-spin-button,
.age-input::-webkit-inner-spin-button { -webkit-appearance: none; margin: 0; }
.age-unit {
  font-size: 14px;
  color: var(--ink-subtle);
  font-weight: 500;
}

.age-rec {
  border-radius: var(--radius);
  padding: 14px 18px;
  display: flex; flex-direction: column; justify-content: center;
  position: relative;
}
.age-rec-label {
  font-size: 11px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--ink-subtle);
  font-weight: 600;
}
.age-rec-value {
  margin-top: 4px;
  font-family: 'Sora', sans-serif;
  font-weight: 700;
  font-size: 24px;
  letter-spacing: -0.025em;
  color: var(--ink);
  font-variant-numeric: tabular-nums;
  background: linear-gradient(135deg, var(--accent) 0%, var(--accent-2) 100%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}
.age-rec-meta {
  margin-top: 2px;
  font-size: 12px;
  color: var(--ink-muted);
}
.age-rec.match::before {
  content: "✓";
  position: absolute;
  top: 12px; right: 14px;
  width: 22px; height: 22px;
  border-radius: 50%;
  background: var(--good);
  color: white;
  display: inline-flex; align-items: center; justify-content: center;
  font-size: 12px; font-weight: 700;
  box-shadow: 0 4px 10px -2px rgba(21,128,61,0.4);
}

/* ---------- Results ---------- */
.results-head {
  display: flex; align-items: baseline; justify-content: space-between;
  margin-bottom: 14px;
  gap: 12px;
}
.results-title {
  font-family: 'Plus Jakarta Sans', sans-serif;
  font-weight: 700; font-size: 16px;
}

.results-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
  perspective: 1400px;
  perspective-origin: 50% 0%;
}
@media (max-width: 480px) { .results-grid { grid-template-columns: 1fr; } }

.result-card {
  background: var(--glass-bg-strong);
  border: 1px solid var(--glass-border);
  -webkit-backdrop-filter: blur(14px) saturate(180%);
  backdrop-filter: blur(14px) saturate(180%);
  border-radius: var(--radius);
  padding: 18px;
  text-align: left;
  cursor: pointer;
  font-family: inherit;
  position: relative;
  transform: translateZ(0);
  transform-style: preserve-3d;
  transition:
    transform .35s cubic-bezier(.2,.7,.2,1),
    box-shadow .35s ease,
    border-color .18s ease;
  box-shadow:
    inset 0 1px 0 var(--glass-inner),
    0 1px 2px rgba(10,10,10,0.03),
    0 6px 14px -4px rgba(10,10,10,0.08);
}
.result-card::before {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: inherit;
  pointer-events: none;
  background: linear-gradient(180deg, rgba(255,255,255,0.35), rgba(255,255,255,0) 30%);
  opacity: 0.5;
  transition: opacity .25s ease;
}
html.dark .result-card::before {
  background: linear-gradient(180deg, rgba(255,255,255,0.06), rgba(255,255,255,0) 30%);
}
.result-card:hover {
  border-color: var(--ink);
  transform: translateY(-4px) rotateX(2.5deg);
  box-shadow:
    inset 0 1px 0 var(--glass-inner),
    0 8px 18px -4px rgba(10,10,10,0.10),
    0 22px 42px -8px rgba(10,10,10,0.14);
}
.result-card:hover::before { opacity: 0.75; }
.result-card.selected {
  border-color: var(--ink);
  transform: translateY(-2px) rotateX(1deg);
  box-shadow:
    inset 0 1px 0 var(--glass-inner),
    0 0 0 1px var(--ink),
    0 10px 24px -6px rgba(10,10,10,0.16);
}
.result-card.is-best::after {
  content: "";
  position: absolute;
  top: -1px; left: 14px; right: 14px; height: 2px;
  background: linear-gradient(90deg, var(--accent), var(--accent-2));
  border-radius: 999px;
  opacity: 0.85;
}

.rc-top {
  display: flex; align-items: center; justify-content: space-between;
  margin-bottom: 12px;
}
.rc-cycle {
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ink-subtle);
  font-weight: 600;
}
.rc-time {
  font-family: 'Sora', 'Plus Jakarta Sans', sans-serif;
  font-weight: 700;
  font-size: clamp(28px, 3.6vw, 36px);
  letter-spacing: -0.03em;
  color: var(--ink);
  line-height: 1;
  display: inline-flex;
  align-items: baseline;
  font-variant-numeric: tabular-nums;
  font-feature-settings: 'tnum' 1;
}
.rc-meta {
  margin-top: 12px;
  display: flex; align-items: center; justify-content: space-between;
  font-size: 12px;
  color: var(--ink-muted);
}
.rc-bar {
  margin-top: 12px;
  height: 4px;
  background: var(--border);
  border-radius: 999px;
  overflow: hidden;
  box-shadow: inset 0 1px 1px rgba(10,10,10,0.06);
}
.rc-bar-fill {
  height: 100%;
  background: var(--ink);
  transition: width .4s ease;
}
.result-card.is-best .rc-bar-fill {
  background: linear-gradient(90deg, var(--accent), var(--accent-2));
}

.tag {
  font-size: 10px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  font-weight: 600;
  padding: 3px 8px;
  border-radius: 999px;
  border: 1px solid currentColor;
}
.tag-best { color: var(--accent); }
.tag-good { color: var(--ink-muted); border-color: var(--border-strong); }
.tag-fair { color: var(--warn); }
.tag-low  { color: var(--bad);  }

.best-summary {
  margin-top: 18px;
  padding: 14px 16px;
  border-radius: var(--radius);
  font-size: 13px;
  color: var(--ink-muted);
  display: flex; align-items: flex-start; gap: 12px;
}
.best-summary strong { color: var(--ink); font-weight: 600; }
.best-summary .accent {
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  font-weight: 700;
}
.best-summary > svg { width: 16px; height: 16px; color: var(--accent); flex-shrink: 0; margin-top: 2px; }

/* ---------- Digit roller (animated rolling numbers) ---------- */
.digit-roll {
  display: inline-block;
  width: 1ch;
  height: 1em;
  overflow: hidden;
  position: relative;
  vertical-align: top;
  line-height: 1;
}
.digit-stack {
  display: flex;
  flex-direction: column;
  transform: translateY(calc(var(--d, 0) * -1em));
  transition: transform 0.55s cubic-bezier(0.34, 1.25, 0.45, 1);
  will-change: transform;
}
.digit-stack > span {
  display: block;
  height: 1em;
  line-height: 1;
  text-align: center;
}
.tsep, .tspace {
  display: inline-block;
  line-height: 1;
}
.tspace { width: 0.3em; }
.tampm {
  display: inline-block;
  font-size: 0.5em;
  font-weight: 600;
  color: var(--ink-subtle);
  letter-spacing: 0.04em;
  margin-left: 0.45em;
  transition: opacity .25s ease, transform .25s ease;
  position: relative;
  top: -0.15em;
}
.tampm.changing { opacity: 0; transform: translateY(-2px); }

/* ---------- Section heads ---------- */
.section-head { max-width: 720px; margin-bottom: 40px; }
.section-head h2 {
  margin: 12px 0 10px;
  font-family: 'Plus Jakarta Sans', sans-serif;
  font-weight: 700;
  font-size: clamp(28px, 3.6vw, 40px);
  letter-spacing: -0.025em;
  line-height: 1.1;
}
.section-head p { color: var(--ink-muted); font-size: 16px; max-width: 56ch; }

/* ---------- Cards (science / tips) — every box has individual depth ---------- */
.card-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 12px;
}
@media (min-width: 640px) { .card-grid { grid-template-columns: repeat(2, 1fr); } }
@media (min-width: 1000px) { .card-grid.cols-4 { grid-template-columns: repeat(4, 1fr); } }
@media (min-width: 1000px) { .card-grid.cols-3 { grid-template-columns: repeat(3, 1fr); } }

.card {
  padding: 26px;
  border-radius: var(--radius-lg);
  position: relative;
  transition: transform .35s cubic-bezier(.2,.7,.2,1), box-shadow .35s ease, border-color .18s;
}
.card:hover {
  transform: translateY(-3px);
  border-color: var(--border-strong);
}
.card .card-num {
  font-family: 'Sora', 'JetBrains Mono', monospace;
  font-weight: 700;
  font-size: 13px;
  color: var(--accent);
  letter-spacing: 0.05em;
  margin-bottom: 14px;
  font-variant-numeric: tabular-nums;
}
.card h3 {
  font-family: 'Plus Jakarta Sans', sans-serif;
  font-size: 18px;
  font-weight: 700;
  margin: 0 0 8px;
  letter-spacing: -0.015em;
}
.card p { margin: 0; color: var(--ink-muted); font-size: 14px; line-height: 1.6; }

/* ---------- Visualization ---------- */
.viz {
  border-radius: var(--radius-xl);
  padding: 28px;
  position: relative;
  overflow: hidden;
}
.viz::before {
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: 100px;
  background: linear-gradient(180deg, rgba(255,255,255,0.4), rgba(255,255,255,0));
  pointer-events: none;
  opacity: 0.5;
}
html.dark .viz::before {
  background: linear-gradient(180deg, rgba(255,255,255,0.04), rgba(255,255,255,0));
}
.viz-head {
  display: flex; flex-wrap: wrap; gap: 14px;
  align-items: center; justify-content: space-between;
  margin-bottom: 18px;
}
.viz-legend {
  display: inline-flex; flex-wrap: wrap; gap: 16px;
  font-size: 12px; color: var(--ink-muted);
}
.viz-legend span { display: inline-flex; align-items: center; gap: 6px; }
.viz-legend i {
  display: inline-block; width: 8px; height: 8px; border-radius: 999px;
  background: currentColor;
}
.legend-awake { color: var(--ink-subtle); }
.legend-rem   { color: var(--accent); }
.legend-light { color: var(--ink-muted); }
.legend-deep  { color: var(--ink); }

.viz-stats {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 12px;
  margin-top: 16px;
}
@media (min-width: 640px) { .viz-stats { grid-template-columns: repeat(4, 1fr); } }
.stat-card {
  background: var(--glass-bg-strong);
  border: 1px solid var(--glass-border);
  -webkit-backdrop-filter: blur(10px);
  backdrop-filter: blur(10px);
  border-radius: var(--radius);
  padding: 14px 16px;
  box-shadow:
    inset 0 1px 0 var(--glass-inner),
    0 1px 2px rgba(10,10,10,0.03),
    0 6px 14px -4px rgba(10,10,10,0.06);
  transition: transform .25s ease, box-shadow .25s ease;
}
.stat-card:hover {
  transform: translateY(-2px);
  box-shadow:
    inset 0 1px 0 var(--glass-inner),
    0 4px 10px -2px rgba(10,10,10,0.10),
    0 10px 22px -6px rgba(10,10,10,0.12);
}
.stat-card .label {
  font-size: 11px; letter-spacing: 0.14em; text-transform: uppercase;
  color: var(--ink-subtle); font-weight: 600;
}
.stat-card .value {
  margin-top: 6px;
  font-family: 'Sora', 'Plus Jakarta Sans', sans-serif;
  font-weight: 700;
  font-size: 22px;
  letter-spacing: -0.03em;
  font-variant-numeric: tabular-nums;
  font-feature-settings: 'tnum' 1;
  display: inline-flex;
  align-items: baseline;
}
.stat-card .value .tampm {
  font-size: 0.55em;
  margin-left: 0.35em;
  top: -0.08em;
}

#cycleCanvas { display: block; width: 100%; margin-top: 8px; }
.viz-ticks {
  display: flex; justify-content: space-between;
  font-family: 'JetBrains Mono', monospace;
  font-size: 11px; color: var(--ink-subtle);
  margin-top: 6px;
}

/* ---------- FAQ ---------- */
.faq-list { display: flex; flex-direction: column; gap: 10px; }
.faq-item {
  padding: 18px 20px;
  border-radius: var(--radius);
  transition: transform .25s ease, box-shadow .25s ease, border-color .18s;
}
.faq-item:hover {
  transform: translateY(-2px);
}
.faq-item summary {
  list-style: none;
  cursor: pointer;
  display: flex; align-items: center; justify-content: space-between;
  font-weight: 600;
  color: var(--ink);
  font-size: 15px;
}
.faq-item summary::-webkit-details-marker { display: none; }
.faq-item summary svg { width: 16px; height: 16px; transition: transform .2s; }
.faq-item[open] summary svg { transform: rotate(180deg); }
.faq-item p {
  margin: 12px 0 0;
  color: var(--ink-muted);
  font-size: 14px;
  line-height: 1.65;
}

/* ---------- Footer ---------- */
.site-footer {
  border-top: 1px solid var(--border);
  padding: 28px 0 36px;
  margin-top: 32px;
}
.site-footer .row {
  display: flex; flex-wrap: wrap; justify-content: space-between; gap: 12px;
  font-size: 13px; color: var(--ink-subtle);
}

/* ---------- Utilities ---------- */
.fade-in { animation: fadeIn .5s ease both; }
@keyframes fadeIn {
  from { opacity: 0; transform: translateY(8px); }
  to   { opacity: 1; transform: translateY(0);   }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation-duration: 0.001ms !important; transition-duration: 0.001ms !important; }
}

:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
  border-radius: 4px;
}

.flex { display: flex; }
.between { justify-content: space-between; }
.center { align-items: center; }
.gap-2 { gap: 8px; } .gap-3 { gap: 12px; } .gap-4 { gap: 16px; }
.mt-1 { margin-top: 4px; } .mt-2 { margin-top: 8px; } .mt-4 { margin-top: 16px; } .mt-6 { margin-top: 24px; }
.hidden { display: none !important; }

/* Hide native time picker icon a bit (visible on hover) */
input[type="time"]::-webkit-calendar-picker-indicator { filter: invert(0) opacity(0.45); cursor: pointer; }
html.dark input[type="time"]::-webkit-calendar-picker-indicator { filter: invert(1) opacity(0.5); }