* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
}

body {
  background: #ffffff; /* чисто белый фон */
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 100vh;
  padding: 20px;
  margin: 0;
}

.auth-container {
  width: 100%;
  max-width: 400px;
  padding: 20px;
}

.auth-card {
  background: #ffffff;
  border-radius: 16px; /* чуть скруглён, но почти квадратный */
  box-shadow: 0 8px 30px rgba(0, 0, 0, 0.06);
  padding: 32px 28px;
  border: 1px solid #f0f0f0;
}

/* Вкладки */
.tabs {
  display: flex;
  gap: 0;
  margin-bottom: 28px;
  border-bottom: 2px solid #f0f0f0;
}

.tab {
  flex: 1;
  background: transparent;
  border: none;
  padding: 12px 0;
  font-size: 18px;
  font-weight: 600;
  color: #8e8e93;
  cursor: pointer;
  transition: all 0.2s;
  border-bottom: 3px solid transparent;
  margin-bottom: -2px;
}
.tab:hover {
  color: #1c1c1e;
}
.tab.active {
  color: #1c1c1e;
  border-bottom-color: #00e676; /* яркий лайм */
}

/* Формы */
.auth-form {
  display: none;
  flex-direction: column;
  gap: 18px;
}
.auth-form.active {
  display: flex;
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 6px;
}
.form-group label {
  font-size: 14px;
  font-weight: 500;
  color: #1c1c1e;
}
.form-group input {
  padding: 14px 16px;
  border: 1px solid #d1d1d6;
  border-radius: 8px; /* более квадратные поля */
  font-size: 16px;
  background: #fafafa;
  transition: border 0.2s, background 0.2s, box-shadow 0.2s;
  color: #1c1c1e;
}
.form-group input:focus {
  outline: none;
  border-color: #00e676;
  background: #ffffff;
  box-shadow: 0 0 0 4px rgba(0, 230, 118, 0.15);
}

/* Кнопка */
.btn-primary {
  width: 100%;
  padding: 14px;
  background: #1c1c1e; /* чёрная */
  color: white;
  border: none;
  border-radius: 8px;
  font-size: 18px;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.2s, transform 0.1s, box-shadow 0.2s;
}
.btn-primary:hover {
  background: #2c2c2e;
  box-shadow: 0 4px 14px rgba(0, 0, 0, 0.08);
}
.btn-primary:active {
  transform: scale(0.97);
}

.form-error {
  font-size: 14px;
  text-align: center;
  min-height: 24px;
  margin-top: 4px;
}

.auth-footer {
  margin-top: 24px;
  text-align: center;
  font-size: 13px;
  color: #8e8e93;
  border-top: 1px solid #f0f0f0;
  padding-top: 16px;
}

@media (max-width: 480px) {
  .auth-card {
    padding: 24px 18px;
  }
  .tab {
    font-size: 16px;
    padding: 10px 0;
  }
  .btn-primary {
    font-size: 16px;
    padding: 12px;
  }
}