* {
    box-sizing: border-box;
}

body {
    margin: 0;
    padding: 28px 18px 48px;
    background: #f1f5f9;
    color: #263445;
    font-family: Arial, sans-serif;
}

.pagina {
    width: min(100%, 980px);
    margin: 0 auto;
}

h1 {
    margin: 0 0 24px;
    text-align: center;
    color: #203d59;
}

.panel,
.tarjeta {
    overflow: hidden;
    border: 1px solid #dce3e9;
    border-radius: 8px;
    background: #fff;
    box-shadow: 0 3px 12px rgba(0, 0, 0, .08);
}

.panel-titulo {
    margin: 0;
    padding: 12px 18px;
    background: #17466c;
    color: #fff;
    font-size: 19px;
}

.busqueda {
    padding: 18px 20px 8px;
}

.busqueda > label,
.campo > label {
    font-weight: 700;
}

.busqueda-controles {
    display: flex;
    gap: 10px;
    margin-top: 8px;
}

.busqueda-controles input {
    flex: 1;
}

#alumno-form {
    padding: 10px 20px 20px;
}

.campo {
    display: grid;
    grid-template-columns: minmax(140px, 185px) minmax(0, 1fr);
    align-items: center;
    gap: 12px;
    margin: 10px 0;
}

input,
select {
    width: 100%;
    min-height: 38px;
    padding: 8px 10px;
    border: 1px solid #cbd4dc;
    border-radius: 4px;
    background: #fff;
    color: #263445;
    font: inherit;
}

input:focus,
select:focus {
    border-color: #1681d5;
    outline: 2px solid rgba(22, 129, 213, .15);
}

.foto-controles {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 8px 12px;
}

.foto-controles input {
    flex-basis: 100%;
    padding: 5px;
}

.foto-controles img {
    width: 82px;
    height: 82px;
    border: 1px solid #dce3e9;
    border-radius: 4px;
    background: #f4f7f9;
    object-fit: cover;
}

.foto-controles small {
    color: #637386;
}

.acciones {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin: 18px 0 0 197px;
}

.boton {
    min-height: 38px;
    padding: 8px 16px;
    border: 1px solid transparent;
    border-radius: 4px;
    cursor: pointer;
    font: inherit;
    font-weight: 700;
}

.boton:disabled {
    cursor: wait;
    opacity: .65;
}

.boton-azul {
    background: #087ad1;
    color: #fff;
}

.boton-azul:hover {
    background: #086bb6;
}

.boton-claro {
    border-color: #cbd4dc;
    background: #f8fafc;
    color: #35485a;
}

.boton-rojo {
    background: #d9303e;
    color: #fff;
}

.mensaje {
    min-height: 20px;
    margin: 12px 0 0 197px;
    color: #176b3a;
}

.mensaje.error {
    color: #b4232f;
}

.oculto {
    display: none;
}

.lista-alumnos {
    margin-top: 30px;
}

.lista-alumnos > h2 {
    margin: 0 0 16px;
    color: #203d59;
    text-align: center;
}

.contenedor {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 20px;
}

.tarjeta {
    width: min(100%, 300px);
    padding: 18px;
    text-align: center;
}

.foto {
    width: 112px;
    height: 112px;
    border-radius: 50%;
    object-fit: cover;
}

.info h3 {
    margin: 12px 0 8px;
    overflow-wrap: anywhere;
}

.info p {
    color: #4a5a68;
    line-height: 1.45;
    overflow-wrap: anywhere;
}

.editar-btn {
    margin-top: 8px;
}

.sin-alumnos {
    color: #637386;
}

@media (max-width: 600px) {
    body {
        padding: 20px 12px 36px;
    }

    .campo {
        grid-template-columns: 1fr;
        gap: 6px;
    }

    .acciones,
    .mensaje {
        margin-left: 0;
    }
}