:root { --navy: #1f2d4d; --orange: #f08c00; --bg: #f4f6fa; --text: #1f2d4d; }
* { box-sizing: border-box; }
body { margin: 0; min-height: 100vh; display: flex; align-items: center; justify-content: center;
       background: var(--bg); color: var(--text); font-family: system-ui, "Hiragino Sans", "Yu Gothic UI", sans-serif; padding: 16px; }
.box { background: #fff; border-radius: 12px; padding: 32px 24px; max-width: 420px; width: 100%;
       box-shadow: 0 4px 16px rgba(31,45,77,.12); text-align: center; border-top: 6px solid var(--navy); }
h1 { margin: 0 0 12px; font-size: 22px; }
p { line-height: 1.6; }
.btn { display: inline-block; margin-top: 12px; padding: 12px 24px; border-radius: 8px; background: var(--orange);
       color: #fff; text-decoration: none; font-weight: bold; }