/* =========================
   SITE PÚBLICO (ALUNOS)
   MOBILE FIRST
   ========================= */

body {
    margin: 0;
    font-family: Arial, sans-serif;
    background: #f5f5f5;
    color: #222;
}

/* HEADER SIMPLES */
header {
    background: #29557d;
    color: #fff;
    padding: 15px;
    text-align: center;
}

header h1 {
    font-size: 20px;
    margin: 0;
}

/* CONTEÚDO PRINCIPAL */
main {
    padding: 15px;
}

/* CARD DE AULA */
.aula-card {
    background: #fff;
    padding: 15px;
    margin-bottom: 15px;
    border-radius: 10px;
    border: 1px solid #ddd;
}

/* TÍTULO */
.aula-card h3 {
    font-size: 18px;
    margin-top: 0;
}

/* BOTÃO PADRÃO */
.btn {
    display: inline-block;
    padding: 14px 16px;
    background: #29557d;
    color: #fff;
    text-decoration: none;
    border-radius: 8px;
    font-size: 16px;
    text-align: center;
}

/* BOTÃO GRANDE MOBILE (idosos) */
.btn-large {
    width: 100%;
    text-align: center;
    font-size: 18px;
}

/* FOOTER */
footer {
    margin-top: 30px;
    background: #111;
    color: #ccc;
    padding: 15px;
    text-align: center;
}

footer img {
    max-width: 160px;
    margin-top: 10px;
}
.btn-assistir {
    display: inline-block;
    padding: 8px 14px;
    background: #e50914; /* vermelho tipo YouTube */
    color: #fff;
    text-decoration: none;
    border-radius: 6px;
    font-weight: bold;
    font-size: 14px;
    transition: 0.2s ease;
    max-width: 100%;
    text-align: center;
    white-space: nowrap;
}

.btn-assistir:hover {
    background: #b00610;
    transform: scale(1.03);
}

/* =========================
   DESKTOP (EXPANSÃO FUTURA)
   ========================= */
@media (min-width: 768px) {

    main {
        max-width: 900px;
        margin: auto;
    }

    header h1 {
        font-size: 24px;
    }
}