:root {
  --green: #03cf5d;
  --focus: #24388d;
  --border-gray: #dadada;
  --error-bg: #e9f0fd;
  --error-text: #ff0000;
  --black: #121212;
  --text-gray: #999999;
}

* {
  box-sizing: border-box;
}

body {
  font-size: 16px;
  color: var(--black);

  display: flex;
  align-items: center;
  justify-content: center;

  min-height: 100vh;
}

.sr-only {
  position: absolute;
  inline-size: 1px;
  block-size: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  border: 0;
}

.login-container {
  inline-size: 100%;
  padding-inline: 1.25rem;

  @media (min-width: 48rem) {
    inline-size: 500px;
  }
}

.logo {
  inline-size: 230px;
  margin-block-end: 1.875rem;
  margin-inline: auto;
  text-align: center;

  & a:focus {
    outline: 2px solid var(--focus);
    outline-offset: 4px;
  }
}

.login-form {
  display: flex;
  flex-direction: column;

  .form-group {
    margin-bottom: 0.625rem;
    position: relative;

    & input {
      inline-size: 100%;
      block-size: 2.8125rem;
      padding-inline: 0.9375rem;

      font-size: 0.875rem;
      border: 1px solid var(--border-gray);
      background-color: #fff;
      outline: none;

      &:focus {
        border-color: var(--green);
        background-color: var(--error-bg);
      }

      /* [검색] */
      /* 가장 현대적이고 권장되는 방식은 :user-invalid를 사용하는 것이지만, 구형 브라우저 대응을 위해 :placeholder-shown을 활용한 꼼수(Trick)도 많이 사용됩니다. */
      &:not(:placeholder-shown):invalid {
        border-color: var(--error-text);

        & + .err {
          display: block;
        }
      }
    }

    .err {
      display: none;
      color: var(--error-text);
      font-size: 0.75rem;
      margin-block-start: 0.25rem;
    }
  }

  .btn-login {
    inline-size: 100%;
    block-size: 2.8125rem;
    margin-top: 1.25rem;

    background: var(--green);
    color: #fff;

    border: none;
    font-size: 1rem;
    font-weight: 700;
    cursor: pointer;
  }
}

.login-options {
  display: flex;
  margin-block-start: 0.625rem;
  justify-content: flex-end;

  @media (min-width: 48rem) {
    justify-content: space-between;
  }

  .keep-login {
    display: flex;
    align-items: center;

    & label {
      display: flex;
      align-items: center;
      font-size: 0.875rem;
      cursor: pointer;
      outline: none;

      &::before {
        content: '';
        inline-size: 24px;
        block-size: 24px;
        margin-bottom: 5px;
        background: url('../assets/profiles/unchecked.svg') no-repeat center;
      }

      &:focus {
        outline: 2px solid var(--focus);
        outline-offset: 2px;
      }
    }

    & input:checked + label::before {
      background-image: url('../assets/profiles/checked.svg');
    }
  }

  .ip-security {
    display: none;

    @media (min-width: 48rem) {
      display: flex;
      align-items: center;
      font-size: 1rem;
    }

    .ip-title {
      text-decoration: none;
      color: inherit;
      margin-inline-end: 5px;
    }

    .ip-switch {
      cursor: pointer;
      font-weight: bold;
      outline: none;

      &:focus {
        outline: 2px solid var(--focus);
        outline-offset: 2px;
      }

      .on {
        display: none;
        color: var(--green);
      }

      .off {
        color: var(--text-gray);
      }
    }

    & input:checked + .ip-switch {
      .on {
        display: inline;
      }
      .off {
        display: none;
      }
    }
  }
}