:root {
  --bg: #f5f7ff;
  --card-bg: rgba(255, 255, 255, 0.96);
  --text-main: #1b2140;
  --text-sub: #5f647d;
  --text-hint: #8085a0;
  --text-error: #d14646;
  --btn-bg: #4b7bff;
  --btn-bg-hover: #3b68e0;
  --btn-text: #ffffff;
  --border-radius: 18px;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  padding: 0;
  height: 100%;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", system-ui,
    "PingFang SC", "Noto Sans CJK SC", sans-serif;
  background: radial-gradient(circle at top, #fdfbff 0, #edf2ff 45%, #e4ecff 100%);
  color: var(--text-main);
  display: flex;
  align-items: center;
  justify-content: center;
}

.wrap {
  width: 100%;
  padding: 16px;
}

.card {
  max-width: 480px;
  margin: 0 auto;
  background: var(--card-bg);
  border-radius: var(--border-radius);
  box-shadow: 0 18px 40px rgba(15, 35, 95, 0.18);
  padding: 24px 22px 20px;
  backdrop-filter: blur(12px);
}

.content h1 {
  margin: 0;
  font-size: 22px;
  font-weight: 700;
}

.sub {
  margin: 10px 0 0;
  font-size: 14px;
  line-height: 1.6;
  color: var(--text-sub);
}

.actions {
  margin-top: 24px;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.btn {
  width: 100%;
  border: none;
  outline: none;
  border-radius: 999px;
  padding: 11px 16px;
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
  background: var(--btn-bg);
  color: var(--btn-text);
  transition: transform 0.08s ease, box-shadow 0.08s ease, background 0.12s ease;
  box-shadow: 0 10px 20px rgba(75, 123, 255, 0.32);
}

.btn:hover {
  background: var(--btn-bg-hover);
  transform: translateY(-1px);
  box-shadow: 0 14px 26px rgba(75, 123, 255, 0.4);
}

.btn:active {
  transform: translateY(0);
  box-shadow: 0 8px 18px rgba(75, 123, 255, 0.28);
}

.btn:disabled {
  opacity: 0.55;
  cursor: not-allowed;
  box-shadow: none;
}

.hint {
  margin-top: 12px;
  font-size: 13px;
  color: var(--text-hint);
}

.hint.error {
  color: var(--text-error);
}

@media (max-width: 480px) {
  .card {
    padding: 20px 18px 18px;
  }

  .content h1 {
    font-size: 20px;
  }

  .sub {
    font-size: 13px;
  }

  .btn {
    font-size: 14px;
  }
}