* {
  box-sizing: border-box;
  font-family: Arial, Helvetica, sans-serif;
}

body {
  background: #f4f4f4;
  display: flex;
  justify-content: center;
  padding-top: 60px;
}

.container {
  background: white;
  padding: 30px;
  border-radius: 10px;
  box-shadow: 0 2px 8px rgba(0,0,0,0.1);
  width: 100%;
  max-width: 380px;
}

h1 {
  text-align: center;
  font-size: 1.4rem;
  margin-bottom: 20px;
}

.abas {
  display: flex;
  margin-bottom: 16px;
}

.aba {
  flex: 1;
  padding: 10px;
  border: none;
  background: #eee;
  cursor: pointer;
}

.aba.ativa {
  background: #2563eb;
  color: white;
}

form {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

input, button[type="submit"] {
  padding: 10px;
  border-radius: 6px;
  border: 1px solid #ccc;
}

button[type="submit"] {
  background: #2563eb;
  color: white;
  border: none;
  cursor: pointer;
}

.escondido {
  display: none;
}

.mensagem {
  text-align: center;
  margin-top: 12px;
  font-size: 0.9rem;
}

.topo-tarefas {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 16px;
}

.topo-tarefas h2 {
  font-size: 1.2rem;
}

#btn-sair {
  background: #eee;
  border: none;
  padding: 6px 12px;
  border-radius: 6px;
  cursor: pointer;
  font-size: 0.85rem;
}

#form-nova-tarefa {
  display: flex;
  flex-direction: row;
  gap: 8px;
  margin-bottom: 16px;
}

#form-nova-tarefa input {
  flex: 1;
}

#form-nova-tarefa button {
  background: #2563eb;
  color: white;
  border: none;
  border-radius: 6px;
  padding: 0 16px;
  cursor: pointer;
  font-size: 1.2rem;
}

#lista-tarefas {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

#lista-tarefas li {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px;
  background: #f9f9f9;
  border-radius: 6px;
}

#lista-tarefas li.concluida span {
  text-decoration: line-through;
  color: #999;
}

#lista-tarefas li span {
  flex: 1;
}

#lista-tarefas li button {
  background: none;
  border: none;
  cursor: pointer;
  font-size: 1rem;
  color: #dc2626;
}