:root {
  --ink: #e4e4e7;
  --black: #09090b;
  --black-2: #18181b;
  --black-3: #27272a;
  --accent: #6366f1;
  --accent-2: #818cf8;
  --accent-dim: rgba(99, 102, 241, 0.12);
  --accent-glow: rgba(99, 102, 241, 0.25);
  --red: #ef4444;
  --red-dim: rgba(239, 68, 68, 0.12);
  --green: #22c55e;
  --green-dim: rgba(34, 197, 94, 0.12);
  --white: #ffffff;
  --cream: #fafafa;
  --muted: #a1a1aa;
  --border: rgba(255, 255, 255, 0.06);
  --border-accent: rgba(99, 102, 241, 0.2);
  --surface: rgba(24, 24, 27, 0.95);
  --surface-elevated: rgba(39, 39, 42, 0.8);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  width: 100%;
  min-height: 100%;
  font-family: "DM Sans", sans-serif;
  color: var(--ink);
  background: var(--black);
  background-image:
    radial-gradient(circle at 50% 0%, rgba(99, 102, 241, 0.04), transparent 60%);
}

button, input, textarea, select { font: inherit; }
button { touch-action: manipulation; }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }
::selection { background: var(--accent); color: var(--white); }

.app-shell { width: 100%; min-height: 100%; overflow-x: hidden; }
.display-face { font-family: "Fraunces", serif; }
.view-panel[hidden] { display: none !important; }

.nav-button {
  position: relative;
  color: var(--muted);
  transition: color 0.2s;
  white-space: nowrap;
}
.nav-button:after {
  content: "";
  position: absolute;
  left: 50%;
  right: 50%;
  bottom: -10px;
  height: 2px;
  border-radius: 99px;
  background: var(--accent);
  transition: left 0.2s, right 0.2s;
}
.nav-button:hover { color: var(--cream); }
.nav-button[aria-selected="true"] { color: var(--cream); }
.nav-button[aria-selected="true"]:after { left: 0; right: 0; }

.hero-grid {
  background: linear-gradient(180deg, var(--black) 0%, var(--black-2) 50%, var(--black-3) 100%);
}
.hero-image-wrap:after {
  content: "";
  position: absolute;
  inset: 0;
  background:
    linear-gradient(90deg, var(--black) 0%, transparent 60%),
    linear-gradient(0deg, var(--black) 0%, transparent 50%);
  pointer-events: none;
}

.glass-card {
  background: var(--surface);
  border: 1px solid var(--border);
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.3);
}
.paper-card {
  background: var(--surface);
  border: 1px solid var(--border);
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.2);
}

.field {
  width: 100%;
  border: 1px solid var(--border);
  border-radius: 10px;
  background: var(--black);
  color: var(--cream);
  padding: 0.75rem 0.875rem;
  transition: border-color 0.2s, box-shadow 0.2s;
}
.field::placeholder { color: var(--muted); opacity: 0.6; }
.field:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-dim);
  outline: none;
}
.field option { background: var(--black); color: var(--cream); }

.primary-button {
  background: var(--accent);
  color: var(--white);
  font-weight: 600;
  transition: background 0.2s, transform 0.1s;
}
.primary-button:hover:not(:disabled) {
  background: var(--accent-2);
  transform: translateY(-1px);
}
.accent-button {
  background: var(--black-3);
  color: var(--cream);
  font-weight: 600;
  border: 1px solid var(--border);
  transition: background 0.2s, border-color 0.2s;
}
.accent-button:hover:not(:disabled) {
  background: var(--accent-dim);
  border-color: var(--border-accent);
}
.primary-button:disabled, .accent-button:disabled { opacity: 0.5; cursor: wait; }

.record-card {
  animation: fadeIn 0.3s ease both;
  border-left: 3px solid var(--accent);
}
@keyframes fadeIn {
  from { opacity: 0; transform: translateY(8px); }
  to { opacity: 1; transform: none; }
}

.metric-number { font-variant-numeric: tabular-nums; }

.tier-card { transition: transform 0.2s, box-shadow 0.2s; }
.tier-card:hover { transform: translateY(-4px); }
.tier-card.is-selected {
  box-shadow: 0 0 0 2px var(--accent), 0 8px 24px rgba(99, 102, 241, 0.15);
}

.toast {
  transform: translate(-50%, 16px);
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.2s, transform 0.2s;
}
.toast.show { transform: translate(-50%, 0); opacity: 1; }

.upload-zone.dragging { border-color: var(--accent); background: var(--accent-dim); }
.filter-button[aria-pressed="true"] { background: var(--accent); color: var(--white); border-color: var(--accent); }

.exercise-item.is-added { border-color: var(--accent); background: var(--accent-dim); }
.session-set:has(input:checked) { background: var(--accent); color: var(--white); }

.timer-ring {
  background: conic-gradient(var(--accent) var(--timer-progress, 0%), var(--black-3) 0);
}

input[type=checkbox] {
  width: 16px;
  height: 16px;
  border-radius: 4px;
  border: 1px solid var(--border);
  background: var(--black);
  cursor: pointer;
  transition: background 0.15s, border-color 0.15s;
}
input[type=checkbox]:checked {
  background: var(--accent);
  border-color: var(--accent);
}
input[type=checkbox]:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

#share-modal { display: none; }
#share-modal:not(.hidden) { display: flex; }

@media (max-width: 767px) {
  .nav-scroller { overflow-x: auto; scrollbar-width: none; }
  .nav-scroller::-webkit-scrollbar { display: none; }
  .nav-button:after { bottom: -7px; }
}

@media (prefers-reduced-motion: reduce) {
  *, *:before, *:after {
    scroll-behavior: auto !important;
    animation-duration: 0.01ms !important;
    transition-duration: 0.01ms !important;
  }
}