:root {
  --bg: #0a0e14;
  --bg-elevated: #121820;
  --card: #161d28;
  --card-border: rgba(255, 255, 255, 0.06);
  --text: #eef3f9;
  --muted: #8b9cb0;
  --accent: #2dd4a8;
  --accent-dim: #1a9b7a;
  --accent-glow: rgba(45, 212, 168, 0.15);
  --error: #f87171;
  --warn: #fbbf24;
  --radius: 16px;
  --radius-sm: 10px;
  --nav-h: 4.25rem;
  --zone-z1: #60a5fa;
  --zone-z2: #34d399;
  --zone-z3: #fbbf24;
  --zone-z4: #fb923c;
  --zone-z5: #f87171;
  --hr-easy: var(--zone-z1);
  --hr-tempo: var(--zone-z3);
  --hr-threshold: var(--zone-z4);
  font-family: "DM Sans", system-ui, -apple-system, sans-serif;
}

* { box-sizing: border-box; }

html { color-scheme: dark; }

body {
  margin: 0;
  background: var(--bg);
  background-image:
    radial-gradient(ellipse 80% 50% at 50% -20%, rgba(45, 212, 168, 0.08), transparent),
    radial-gradient(ellipse 60% 40% at 100% 0%, rgba(96, 165, 250, 0.05), transparent);
  color: var(--text);
  line-height: 1.5;
  min-height: 100vh;
  font-size: 15px;
}

.app-shell {
  min-height: 100vh;
  padding-bottom: calc(var(--nav-h) + env(safe-area-inset-bottom, 0px));
}

.top-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.85rem 1rem 0.5rem;
  position: sticky;
  top: 0;
  z-index: 20;
  background: linear-gradient(to bottom, var(--bg) 70%, transparent);
  backdrop-filter: blur(8px);
}

.brand {
  display: flex;
  align-items: center;
  gap: 0.65rem;
}

.brand-mark {
  width: 2.25rem;
  height: 2.25rem;
  border-radius: 12px;
  background: linear-gradient(135deg, var(--accent), #3b82f6);
  box-shadow: 0 4px 20px var(--accent-glow);
}

.brand h1 {
  margin: 0;
  font-size: 1.25rem;
  font-weight: 700;
  letter-spacing: -0.02em;
}

.tagline {
  margin: 0;
  color: var(--muted);
  font-size: 0.72rem;
}

main {
  max-width: 480px;
  margin: 0 auto;
  padding: 0 0.85rem 1rem;
}

.view { animation: fadeIn 0.2s ease; }

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(4px); }
  to { opacity: 1; transform: none; }
}

.card {
  background: var(--card);
  border: 1px solid var(--card-border);
  border-radius: var(--radius);
  padding: 1rem 1.05rem;
  margin-bottom: 0.75rem;
}

.card h2, .card h3 {
  margin: 0 0 0.65rem;
  font-size: 0.95rem;
  font-weight: 600;
  letter-spacing: -0.01em;
}

.card-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.5rem;
  margin-bottom: 0.65rem;
}

.card-head h2 { margin: 0; }

label {
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
  font-size: 0.8rem;
  color: var(--muted);
  margin-bottom: 0.75rem;
}

input, button, .btn-link {
  font: inherit;
  border-radius: var(--radius-sm);
}

input {
  padding: 0.7rem 0.85rem;
  background: var(--bg);
  color: var(--text);
  border: 1px solid var(--card-border);
}

input:focus {
  outline: 2px solid var(--accent-dim);
  outline-offset: 1px;
}

.btn-primary, button.primary {
  width: 100%;
  padding: 0.85rem 1rem;
  background: linear-gradient(135deg, var(--accent), var(--accent-dim));
  color: #042018;
  border: none;
  font-weight: 600;
  cursor: pointer;
}

button.secondary, .btn-secondary {
  padding: 0.55rem 0.85rem;
  background: transparent;
  border: 1px solid var(--card-border);
  color: var(--text);
  cursor: pointer;
  font-size: 0.85rem;
}

.icon-btn {
  background: var(--card);
  border: 1px solid var(--card-border);
  color: var(--muted);
  width: 2.5rem;
  height: 2.5rem;
  border-radius: 12px;
  display: grid;
  place-items: center;
  cursor: pointer;
}

.error { color: var(--error); font-size: 0.88rem; }
.muted { color: var(--muted); font-size: 0.82rem; }
.hint { color: var(--muted); font-size: 0.85rem; margin-top: 0; }

.banner {
  background: rgba(251, 191, 36, 0.12);
  color: var(--warn);
  padding: 0.65rem 0.85rem;
  border-radius: var(--radius-sm);
  margin-bottom: 0.75rem;
  font-size: 0.85rem;
  border: 1px solid rgba(251, 191, 36, 0.2);
}

.hidden { display: none !important; }

.user-chip {
  font-size: 0.75rem;
  color: var(--muted);
  margin: 0 0 0.5rem 0.25rem;
}

.stat-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 0.5rem;
}

.stat {
  background: var(--bg-elevated);
  border-radius: var(--radius-sm);
  padding: 0.65rem 0.75rem;
}

.stat-label {
  font-size: 0.68rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--muted);
}

.stat-value {
  font-size: 1.35rem;
  font-weight: 700;
  margin-top: 0.15rem;
}

.progress-wrap {
  margin-top: 0.75rem;
}

.progress-label {
  display: flex;
  justify-content: space-between;
  font-size: 0.78rem;
  color: var(--muted);
  margin-bottom: 0.35rem;
}

.progress-bar {
  height: 8px;
  background: var(--bg);
  border-radius: 99px;
  overflow: hidden;
}

.progress-fill {
  height: 100%;
  background: linear-gradient(90deg, var(--accent-dim), var(--accent));
  border-radius: 99px;
  transition: width 0.4s ease;
}

.session-block {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.session-row {
  display: grid;
  grid-template-columns: 5.5rem 1fr;
  gap: 0.5rem;
  font-size: 0.85rem;
}

.session-row dt {
  color: var(--muted);
  margin: 0;
}

.session-row dd {
  margin: 0;
}

.zone-badge {
  display: inline-block;
  padding: 0.15rem 0.5rem;
  border-radius: 6px;
  font-size: 0.72rem;
  font-weight: 600;
  background: var(--zone-z2);
  color: #042018;
}

.zone-badge.qualitat { background: var(--zone-z4); color: #1a0800; }
.zone-badge.facil { background: var(--zone-z1); color: #031020; }

.workout-card {
  padding: 0.85rem 0;
  border-bottom: 1px solid var(--card-border);
  cursor: pointer;
}

.workout-card:last-child { border-bottom: none; }

.workout-card:active { opacity: 0.85; }

.workout-title { font-weight: 600; font-size: 0.95rem; }

.workout-meta {
  font-size: 0.78rem;
  color: var(--muted);
  margin-top: 0.2rem;
}

.hr-pill {
  display: inline-flex;
  align-items: center;
  gap: 0.25rem;
  font-size: 0.72rem;
  padding: 0.1rem 0.45rem;
  border-radius: 6px;
  background: rgba(248, 113, 113, 0.15);
  color: var(--zone-z5);
}

.analysis-box {
  margin-top: 0.65rem;
  padding: 0.65rem 0.75rem;
  background: var(--bg-elevated);
  border-radius: var(--radius-sm);
  font-size: 0.84rem;
  white-space: pre-wrap;
  border-left: 3px solid var(--accent);
}

.sync-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0.5rem;
}

.sheet-tabs {
  display: flex;
  gap: 0.35rem;
  overflow-x: auto;
  padding-bottom: 0.35rem;
  margin-bottom: 0.65rem;
  -webkit-overflow-scrolling: touch;
}

.sheet-tab {
  flex: 0 0 auto;
  padding: 0.45rem 0.75rem;
  border-radius: 99px;
  border: 1px solid var(--card-border);
  background: transparent;
  color: var(--muted);
  font-size: 0.78rem;
  cursor: pointer;
}

.sheet-tab.active {
  background: var(--accent-glow);
  border-color: var(--accent-dim);
  color: var(--accent);
}

.table-scroll {
  overflow-x: auto;
  margin: 0 -0.5rem;
  padding: 0 0.5rem;
}

.data-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.72rem;
  min-width: 520px;
}

.data-table th,
.data-table td {
  padding: 0.45rem 0.4rem;
  border-bottom: 1px solid var(--card-border);
  text-align: left;
  vertical-align: top;
}

.data-table th {
  color: var(--muted);
  font-weight: 500;
  position: sticky;
  top: 0;
  background: var(--card);
}

.data-table td.editable {
  background: rgba(255, 242, 204, 0.08);
}

.data-table input.cell-input {
  width: 100%;
  min-width: 3rem;
  padding: 0.35rem;
  font-size: 0.72rem;
}

.chart-card canvas {
  width: 100%;
  height: 160px;
  display: block;
}

.bottom-nav {
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  height: var(--nav-h);
  padding-bottom: env(safe-area-inset-bottom, 0);
  background: rgba(10, 14, 20, 0.92);
  backdrop-filter: blur(12px);
  border-top: 1px solid var(--card-border);
  display: flex;
  justify-content: space-around;
  align-items: center;
  z-index: 30;
}

.nav-item {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.15rem;
  background: none;
  border: none;
  color: var(--muted);
  font-size: 0.65rem;
  padding: 0.35rem;
  cursor: pointer;
}

.nav-item.active { color: var(--accent); }

.nav-icon { font-size: 1.1rem; }

.auth-card { margin-top: 1rem; animation: fadeIn 0.2s ease; }

.detail-back {
  margin-bottom: 0.75rem;
}

.hero-stats {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0.65rem;
  margin-bottom: 0.75rem;
}

.hero-stat {
  background: var(--card);
  border: 1px solid var(--card-border);
  border-radius: var(--radius);
  padding: 0.85rem 1rem;
  text-align: center;
}

.hero-value {
  font-size: 1.65rem;
  font-weight: 700;
  letter-spacing: -0.03em;
  line-height: 1.1;
}

.hero-label {
  font-size: 0.72rem;
  color: var(--muted);
  margin-top: 0.25rem;
}

.headline-sub {
  margin: 0 0 0.65rem;
  font-size: 0.78rem;
}

.card-emoji { margin-right: 0.25rem; }

.big-number {
  font-size: 1.75rem;
  font-weight: 700;
  margin: 0 0 0.35rem;
  letter-spacing: -0.02em;
}

.target-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.35rem;
  margin-bottom: 0.65rem;
}

.target-chip {
  font-size: 0.72rem;
  padding: 0.2rem 0.5rem;
  border-radius: 999px;
  background: var(--accent-glow);
  color: var(--accent);
  border: 1px solid rgba(45, 212, 168, 0.25);
}

.tl-green { color: var(--zone-z2); }
.tl-amber { color: var(--warn); }
.tl-red { color: var(--error); }
.tl-blue { color: var(--zone-z1); }
.tl-unknown { color: var(--muted); }

.traffic-note {
  font-size: 0.78rem;
  margin-top: 0.65rem;
  margin-bottom: 0;
  padding: 0.45rem 0.55rem;
  border-radius: var(--radius-sm);
  background: rgba(255, 255, 255, 0.04);
}

.zone-bars { display: flex; flex-direction: column; gap: 0.35rem; margin-top: 0.5rem; }

.zone-bar-row {
  display: grid;
  grid-template-columns: 1.75rem 1fr 2.5rem;
  align-items: center;
  gap: 0.35rem;
  font-size: 0.75rem;
}

.zone-bar-track {
  height: 8px;
  background: rgba(255, 255, 255, 0.06);
  border-radius: 4px;
  overflow: hidden;
}

.zone-bar-fill { height: 100%; border-radius: 4px; }

.zone-bar-pct { text-align: right; color: var(--muted); }

.splits-table td, .splits-table th { font-size: 0.78rem; padding: 0.35rem 0.4rem; }

.loading-state {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 2rem;
  color: var(--muted);
}

.spinner {
  width: 1rem;
  height: 1rem;
  border: 2px solid rgba(255, 255, 255, 0.15);
  border-top-color: var(--accent);
  border-radius: 50%;
  animation: spin 0.7s linear infinite;
}

@keyframes spin { to { transform: rotate(360deg); } }

.analysis-warn { border-left: 3px solid var(--warn); }

.toggle-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
  font-size: 0.9rem;
  margin-bottom: 0.5rem;
}

.upload-preview-list {
  margin: 0.75rem 0 0;
  padding-left: 1.1rem;
  font-size: 0.82rem;
  color: var(--muted);
  line-height: 1.45;
}

@media (min-width: 480px) {
  .brand h1 { font-size: 1.4rem; }
}