:root {
  --fundo-escuro: #0d1117;
  --cinza-card: #161b22;
  --borda-sutil: #30363d;
  --azul-tech: #00bfff;
  --prata-metalico: #c0c0c0;
  --texto-principal: #e6edf3;
  --texto-secundario: #8b949e;
  --vermelho-erro: #ff6b6b;
  --transicao: all 0.3s ease;
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  background-color: var(--fundo-escuro);
  color: var(--texto-principal);
  display: flex;
  justify-content: center;
  align-items: center;
  height: 100vh;
}

.site-header {
  position: absolute; 
  top: 20px;
  left: 20px;
  display: flex;
  align-items: center;
  gap: 8px;
  text-decoration: none;
  color: var(--texto-secundario);
  transition: var(--transicao);
}

.site-header:hover {
  color: var(--azul-tech);
}

.site-header i {
  font-size: 20px;
}

.site-header .back-text {
  font-size: 16px;
  font-weight: 500;
}

.login-container {
  background-color: var(--cinza-card);
  padding: 40px;
  border-radius: 10px;
  border: 1px solid var(--borda-sutil);
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
  width: 100%;
  max-width: 380px;
  text-align: center;
  animation: fadeIn 0.5s ease-out;
}

.logo-container {
    margin-bottom: 20px;
}

.logo-container img {
    max-width: 180px;
    height: auto;
}


h2 {
  margin-bottom: 30px;
  font-size: 24px;
  font-weight: 600;
  color: var(--texto-principal);
}

.input-group {
  margin-bottom: 20px;
  display: flex;
  align-items: center;
  background-color: var(--fundo-escuro);
  border: 1px solid var(--borda-sutil);
  border-radius: 6px;
  transition: var(--transicao);
}

.input-group:focus-within {
  border-color: var(--azul-tech);
  box-shadow: 0 0 0 3px rgba(0, 191, 255, 0.2);
}

.input-group i {
  color: var(--texto-secundario);
  padding: 0 15px;
  transition: var(--transicao);
}

.input-group:focus-within i {
  color: var(--azul-tech);
}

.input-group input {
  flex-grow: 1;
  background: none;
  border: none;
  outline: none;
  color: var(--texto-principal);
  font-size: 16px;
  padding: 14px 0;
}

button[type="submit"] {
  width: 100%;
  padding: 14px;
  background-color: var(--azul-tech);
  border: none;
  color: var(--fundo-escuro);
  font-size: 16px;
  font-weight: 700;
  border-radius: 6px;
  cursor: pointer;
  transition: var(--transicao);
  margin-top: 10px; 
}

button[type="submit"]:hover {
  filter: brightness(1.1);
  transform: translateY(-2px);
  box-shadow: 0 4px 15px rgba(0, 191, 255, 0.2);
}

.error-message {
  color: var(--vermelho-erro);
  font-size: 14px;
  margin-top: 15px;
  min-height: 20px;
}

@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(-10px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}