:root {
  --bg-top: #f5efe4;
  --bg-bottom: #e2ecf4;
  --card-bg: #ffffff;
  --text-main: #1f2a37;
  --text-sub: #556070;
  --line: #d6dde6;
  --accent: #1f6feb;
  --accent-hover: #175dc6;
  --ok: #147d4d;
  --error: #c53d3d;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: "Pretendard", "Noto Sans KR", "Segoe UI", sans-serif;
  color: var(--text-main);
  background: linear-gradient(160deg, var(--bg-top), var(--bg-bottom));
}

.login-page {
  min-height: 100vh;
  display: grid;
  place-items: center;
  padding: 24px;
}

.login-card {
  width: 100%;
  max-width: 420px;
  background: var(--card-bg);
  border: 1px solid var(--line);
  border-radius: 18px;
  padding: 32px 28px;
  box-shadow: 0 16px 36px rgba(15, 23, 42, 0.08);
}

.eyebrow {
  margin: 0;
  color: var(--accent);
  font-weight: 700;
  letter-spacing: 0.1em;
  font-size: 12px;
}

h1 {
  margin: 8px 0 6px;
  font-size: 30px;
}

.subtitle {
  margin: 0 0 24px;
  color: var(--text-sub);
  font-size: 14px;
}

.auth-switch {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 8px;
  margin-bottom: 14px;
}

.switch-btn {
  height: 40px;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: #f9fbfd;
  color: var(--text-sub);
  font-size: 14px;
  font-weight: 700;
  cursor: pointer;
}

.switch-btn.active {
  border-color: var(--accent);
  color: var(--accent);
  background: rgba(31, 111, 235, 0.08);
}

.auth-form {
  display: grid;
  gap: 10px;
}

.auth-form.hidden {
  display: none;
}

.field-label {
  margin-top: 6px;
  font-size: 13px;
  font-weight: 600;
}

input[type="text"],
input[type="password"],
input[type="email"] {
  width: 100%;
  height: 44px;
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 0 12px;
  font-size: 15px;
}

input[type="text"]:focus,
input[type="password"]:focus,
input[type="email"]:focus {
  outline: 2px solid rgba(31, 111, 235, 0.25);
  border-color: var(--accent);
}

input.invalid {
  border-color: var(--error);
}

.field-error {
  min-height: 16px;
  margin: -4px 0 0;
  color: var(--error);
  font-size: 12px;
}

.form-row {
  margin-top: 4px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
  font-size: 13px;
}

.checkbox-label {
  display: flex;
  align-items: center;
  gap: 6px;
  color: var(--text-sub);
}

#login-button {
  margin-top: 8px;
  height: 44px;
  border: 0;
  border-radius: 10px;
  background: var(--accent);
  color: #ffffff;
  font-size: 15px;
  font-weight: 700;
  cursor: pointer;
}

#signup-button {
  margin-top: 8px;
  height: 44px;
  border: 0;
  border-radius: 10px;
  background: var(--accent);
  color: #ffffff;
  font-size: 15px;
  font-weight: 700;
  cursor: pointer;
}

#login-button:hover {
  background: var(--accent-hover);
}

#signup-button:hover {
  background: var(--accent-hover);
}

#login-button:disabled {
  opacity: 0.7;
  cursor: default;
}

#signup-button:disabled {
  opacity: 0.7;
  cursor: default;
}

.text-link {
  color: var(--accent);
  text-decoration: none;
}

.text-link:hover {
  text-decoration: underline;
}

.form-message {
  min-height: 20px;
  margin: 2px 0 0;
  font-size: 13px;
}

.form-message.error {
  color: var(--error);
}

.form-message.success {
  color: var(--ok);
}

.signup-row {
  margin-top: 20px;
  font-size: 13px;
  color: var(--text-sub);
  text-align: center;
}

@media (max-width: 480px) {
  .login-card {
    padding: 24px 18px;
    border-radius: 14px;
  }

  h1 {
    font-size: 24px;
  }
}