:root {
  --accent: #98cbff;
  --bg: #21252b;
  --bg-card: #272b30;
  --text: #ccc;
  --text-muted: #888;
  --border: rgba(152, 203, 255, 0.2);
  --font: 'Mulish', 'Noto Serif SC', '-apple-system', 'PingFang SC', 'Microsoft YaHei', sans-serif;
  --bg-opacity: 0.05;
  --bg-image: url("https://blog.itousouta15.tw/images/banner.webp");
}

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

html, body {
  height: 100%;
  font-family: var(--font);
  background-color: var(--bg);
  color: var(--text);
  -webkit-font-smoothing: antialiased;
}

body {
  position: relative;
  isolation: isolate;
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 100%;
}

body::before {
  content: '';
  position: fixed;
  inset: 0;
  background-image: var(--bg-image);
  background-size: cover;
  background-position: center;
  background-attachment: fixed;
  opacity: var(--bg-opacity);
  z-index: -1;
  pointer-events: none;
}

.card {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 20px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 56px 48px;
  text-align: center;
  max-width: 480px;
  width: 90%;
}

.title {
  font-size: 42px;
  font-weight: 700;
  color: var(--accent);
  letter-spacing: 2px;
}

.emoji {
  font-size: 28px;
  color: var(--text-muted);
  letter-spacing: 1px;
}

.btn {
  margin-top: 12px;
  display: inline-block;
  padding: 14px 28px;
  border-radius: 10px;
  background: transparent;
  border: 1px solid var(--accent);
  color: var(--accent);
  font-family: var(--font);
  font-size: 16px;
  font-weight: 700;
  text-decoration: none;
  letter-spacing: 0.5px;
  transition: background 0.25s, color 0.25s;
}

.btn:hover {
  background: var(--accent);
  color: var(--bg);
}

@keyframes fadeUp {
  from { opacity: 0; transform: translateY(24px); }
  to   { opacity: 1; transform: translateY(0); }
}

@keyframes breathe {
  0%, 100% { opacity: 1; }
  50%       { opacity: 0.7; }
}

@keyframes sway {
  0%, 100% { transform: rotate(-4deg); }
  50%       { transform: rotate(4deg); }
}

.card {
  animation: fadeUp 0.6s cubic-bezier(0.22, 1, 0.36, 1) both;
}

.title {
  animation: breathe 3.5s ease-in-out infinite;
}

.emoji {
  display: inline-block;
  animation: sway 2.8s ease-in-out infinite;
}

@media (max-width: 480px) {
  .card { padding: 40px 28px; }
  .title { font-size: 32px; }
  .emoji { font-size: 22px; }
}