* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  font-family: Arial, sans-serif;
}

body {
  background: linear-gradient(135deg, #7e4400 0%, #975102 60%, #774002 100%);
  min-height: 100vh;
  display: grid;
  place-items: center;
  padding: 20px;
}

.formulariocaja {
  width: 340px;
  background: #f0f0f0;
  border-radius: 14px;
  border: 2px solid #ddd;
  overflow: hidden;
  padding-bottom: 24px;
  position: relative;
}

.botondeintercambiar {
  display: flex;
  position: relative;
  background: #e0e0e0;
  border-radius: 30px;
  box-shadow: 0 3px 10px rgba(0,0,0,0.2);
  margin: 20px auto 0;
  width: 260px;
  height: 40px;
  overflow: hidden;
}

.botoncambiarcaja {
  flex: 1;
  background: transparent;
  border: none;
  cursor: pointer;
  font-size: 14px;
  font-weight: 600;
  color: #555;
  z-index: 1;
  transition: color 0.4s;
}

#btnvai {
  position: absolute;
  top: 3px;
  left: 3px;
  width: calc(50% - 3px);
  height: calc(100% - 6px);
  background: #1cc1b9;
  border-radius: 30px;
  transition: left 0.5s ease;
  z-index: 0;
}

.robot-img {
  display: block;
  margin: 16px auto 10px;
  width: 90px;
}

.grupo-entradas {
  position: absolute;
  width: 100%;
  padding: 0 24px 8px;
  transition: left 0.5s ease;
}

#frmlogin {
  left: 0;
  top: 120px; 
}

#frmregistrar {
  left: 340px;
  top: 120px;
}

.formulariocaja::after {
  content: '';
  display: block;
  height: 290px;
  margin-top: 120px;
}

.campo-label {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 13px;
  color: #333;
  margin: 12px 0 4px;
}

.campo-input {
  width: 100%;
  height: 36px;
  padding: 0 10px;
  border: 1px solid #ccc;
  border-radius: 6px;
  font-size: 13px;
  background: #fff;
  outline: none;
  transition: border-color 0.3s;
}

.campo-input:focus {
  border-color: #1cc1c1;
}

.captcha-row {
  display: flex;
  gap: 8px;
  align-items: center;
}

.captcha-row .campo-input {
  flex: 1;
}

.captcha-box {
  background: #645f5f;
  border: 1px solid #686767;
  border-radius: 6px;
  padding: 6px 12px;
  font-size: 18px;
  font-weight: bold;
  letter-spacing: 4px;
  color: #222;
  cursor: pointer;
  user-select: none;
  min-width: 70px;
  text-align: center;
  font-family: 'Courier New', monospace;
  transition: background 0.2s;
}

.captcha-box:hover {
  background: #857c7c;
}

/* Botón de envío */
.botonenviar {
  display: block;
  width: 100%;
  height: 40px;
  margin-top: 18px;
  background: #1cc1ab;
  color: #fff;
  border: none;
  border-radius: 8px;
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.3s, transform 0.1s;
}

.botonenviar:hover {
  background: #159ea8;
}

.botonenviar:active {
  transform: scale(0.98);
}