:root {
  --primary: #0f0;
  --bg: #0a0a0a;
  --text: #f2f2f2;
  --accent: #1a1a1a;
  --checked: #1d4025;
}

body {
  margin: 0;
  font-family: 'Segoe UI', sans-serif;
  background: var(--bg);
  color: var(--text);
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

header {
  position: sticky;
  top: 0;
  text-align: center;
  padding: 1rem;
  background: var(--accent);
  z-index: 100;
}

#stats {
  margin-top: 0.5rem;
  font-size: 1rem;
  display: flex;
  justify-content: center;
  gap: 2rem;
  flex-wrap: wrap;
}

footer {
  text-align: center;
  padding: 1rem;
  background: var(--accent);
  font-size: 0.9em;
}

main {
  flex: 1;
  padding: 1rem;
  max-width: 900px;
  margin: 0 auto;
}

#calendar-header {
  display: grid;
  grid-template-columns: repeat(7, 1fr);
  text-align: center;
  margin-bottom: 0.5rem;
}

#calendar-header div {
  font-weight: bold;
  padding: 0.3rem 0;
  border-bottom: 1px solid var(--accent);
}

.calendar-grid {
  display: grid;
  grid-template-columns: repeat(7, 1fr);
  gap: 0.3rem;
}

.day {
  background: #111;
  border: 1px solid var(--accent);
  border-radius: 10px;
  padding: 0.3rem;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: space-between;
  min-height: auto;
  text-align: center;
  transition: transform 0.2s ease;
}

.day:hover {
  transform: scale(1.03);
}

.day .label {
  font-size: 1rem;
  margin-bottom: 0.3rem;
}

.session {
  margin: 0.1rem 0;
}

.session button {
  padding: 0.2rem 0.3rem;
  border: none;
  border-radius: 4px;
  font-size: 1rem;
  cursor: pointer;
}

.session button.checked {
  background: limegreen;
  color: #000;
}

.session button:not(.checked) {
  background: #222;
  color: #ccc;
  border: 1px solid #444;
}

.day.descanso {
  opacity: 0.4;
}

#reset {
  margin-top: 10px;
  padding: 0.4rem 0.8rem;
  border: none;
  background: crimson;
  color: white;
  font-weight: bold;
  border-radius: 5px;
  cursor: pointer;
}

@media (max-width: 480px) {
  #stats {
    flex-direction: column;
    align-items: center;
    gap: 0.3rem;
  }
}

nav {
  display: flex;
  justify-content: center;
  gap: 1rem;
  margin: 1rem 0;
}

nav button {
  background: #333;
  color: white;
  border: none;
  padding: 0.4rem 0.8rem;
  border-radius: 5px;
  cursor: pointer;
}

nav button.active {
  background: limegreen;
  color: black;
}

.corrida-btn {
  background: #111;
  color: lime;
  font-size: 1.2rem;
  border: none;
  cursor: pointer;
  padding: 0.3rem 0.5rem;
  border-radius: 6px;
  margin-bottom: 0.3rem;
  transition: background 0.2s;
}

.corrida-btn.checked {
  background: lime;
  color: black;
  font-weight: bold;
}

.mes-control {
  margin: 1rem auto;
  text-align: center;
  color: white;
}

.mes-selector {
  padding: 0.3rem 0.6rem;
  border-radius: 6px;
  font-size: 1rem;
}