/* ===== RESET BÁSICO ===== */
html, body {
  min-height: 100%;
  margin: 0;
}

/* ===== FONDO GENERAL ===== */
body {
  background-image: url(../img/background.jpg?v=2);
  background-size: cover;              /* llena siempre */
  background-position: center top;
  background-repeat: no-repeat;
}

/* ===== CONTENEDOR PRINCIPAL ===== */
.main-section {
  margin:-75%;
  margin-top:10%;                 /* separa del top sin romper */
}

/* ===== MODAL ===== */
.modal-content {
  background-color: #3b4652;
  opacity: 0.85;
  padding: 0 20px;
  box-shadow: 0 0 23px #848484;
  border-radius: 25px;
}

/* ===== USUARIO ===== */
.user-img {
  margin-top: 5px;
  margin-bottom: 35px;
}

.user-img img {
  width: 100%;
  height: auto;
}

/* ===== FORM ===== */
.form-group input {
  height: 42px;
  font-size: 18px;
  border: 0;
  padding-left: 54px;
  border-radius: 5px;
}

.form-group::before {
  font-family: 'FontAwesome';
  position: absolute;
  left: 28px;
  font-size: 22px;
  padding-top: 4px;
}

.form-group#user-group::before {
  content: "\f007";
}

.form-group#contrasena-group::before {
  content: "\f023";
}

button {
  width: 60%;
  margin: 5px 0 25px;
}

.forgot {
  padding: 5px 0;
}

.forgot a {
  color: white;
}

/* ===== FOOTER ===== */
footer {
  position: fixed;
  bottom: 0;
  left: 0;
  width: 100%;
  padding: 20px 0;
  display: flex;
  justify-content: flex-end;            /* a la derecha */
  padding-right: 30%;
  z-index: 999;
}

/* ===== BOTÓN EBOOK ===== */
.footer-ebook-btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 12px 26px;
  font-size: 15px;
  font-weight: 600;
  color: #ffffff;
  text-decoration: none;
  background: linear-gradient(135deg, #3b82f6, #2563eb);
  border-radius: 999px;
  box-shadow: 0 8px 22px rgba(0, 0, 0, 0.35);
  transition: all 0.3s ease;
}

.footer-ebook-btn i {
  font-size: 16px;
}

.footer-ebook-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 12px 30px rgba(0, 0, 0, 0.45);
  background: linear-gradient(135deg, #2563eb, #1d4ed8);
}

/* ===== MÓVIL ===== */
@media (max-width: 768px) {

  body {
    background-image: url(../img/background3.jpg);
    background-size: cover;             /* nada de % */
    background-position: center center;
    background-attachment: scroll;
  }

  .main-section {
      margin: 0;
      padding-top: 10vh;                   /* separa del top sin romper */
    }

  footer {
    padding: 8px 0;
    padding-right: 33%;
    background-color: rgba(30, 41, 59, 0.9);
  }

  .footer-ebook-btn {
    padding: 8px 16px;
    font-size: 13px;
    border-radius: 20px;
  }

  .footer-ebook-btn i {
    font-size: 13px;
  }
}