/* ===== Reset mínimo ===== */
* {
  box-sizing: border-box;
}
body {
  margin: 0;
  font-family: system-ui, Arial, sans-serif;
  background: #f7f7fb;
  color: #111827;
}

/* ===== Layout ===== */
main,
.app {
  max-width: 720px;
  margin: 40px auto;
  padding: 0 16px;
}
h1 {
  margin: 0 0 16px;
}

/* ===== Formulario ===== */
#formulario {
  display: flex;
  gap: 8px;
  margin-bottom: 12px;
}
#formulario input[type="text"] {
  flex: 1;
  padding: 10px 12px;
  border: 1px solid #e5e7eb;
  border-radius: 10px;
  background: #fff;
}
#formulario button {
  padding: 10px 16px;
  border: 0;
  border-radius: 10px;
  cursor: pointer;
  background: #111827;
  color: #fff;
  font-weight: 600;
}
#formulario button:hover {
  filter: brightness(0.95);
}
#formulario input:focus,
#formulario button:focus {
  outline: 3px solid #bfdbfe;
  outline-offset: 2px;
}

/* ===== Lista de tareas ===== */
#tareas {
  display: grid;
  gap: 10px;
}
.tarea {
  background: #fff;
  border: 1px solid #e5e7eb;
  border-radius: 12px;
  padding: 12px;
  display: flex;
  align-items: center;
  gap: 10px;
  justify-content: space-between;
}

/* Texto de tarea */
.tarea span {
  line-height: 1.3;
}
.completada {
  text-decoration: line-through;
  opacity: 0.7;
}

/* Botones acción */
.tarea button {
  border: 1px solid #e5e7eb;
  background: #fff;
  padding: 6px 10px;
  border-radius: 8px;
  cursor: pointer;
}
.tarea button.completar {
  border-color: #bbf7d0;
}
.tarea button.eliminar {
  border-color: #fecaca;
}
.tarea button:hover {
  filter: brightness(0.97);
}

/* ===== Responsive ===== */
@media (max-width: 480px) {
  .tarea {
    flex-direction: column;
    align-items: flex-start;
  }
  .tarea .acciones {
    width: 100%;
    display: flex;
    gap: 8px;
  }
}
.filtro {
  padding: 10px 16px;
  border: 0;
  border-radius: 10px;
  cursor: pointer;
  background: #7c8eb4;
  color: #fff;
  font-weight: 600;
}