:root { color: #17213a; font-family: Inter, Pretendard, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif; background: #f6f9ff; }
* { box-sizing: border-box; }
body { min-width: 320px; margin: 0; }
button, input { font: inherit; }
button { cursor: pointer; }
button:focus-visible, input:focus-visible, a:focus-visible { outline: 3px solid #8bb4ff; outline-offset: 3px; }
.shell { width: min(100% - 32px, 720px); min-height: 100vh; margin: 0 auto; padding: 42px 0 28px; display: grid; align-content: center; gap: 28px; }
.brand { width: max-content; color: #155eef; font-size: 1.15rem; font-weight: 800; letter-spacing: -.06em; text-decoration: none; }
.brand span { color: #7da6ff; }
.card { padding: clamp(28px, 7vw, 56px); background: #fff; border: 1px solid #dbe6fb; border-radius: 24px; box-shadow: 0 20px 50px rgba(38, 91, 184, .12); }
.eyebrow { margin: 0 0 12px; color: #155eef; font-size: .75rem; font-weight: 800; letter-spacing: .12em; }
h1 { margin: 0; color: #12204a; font-size: clamp(2rem, 7vw, 3.75rem); line-height: 1.08; letter-spacing: -.065em; }
.intro { max-width: 37rem; margin: 20px 0 32px; color: #5c6881; font-size: 1rem; line-height: 1.7; }
label { display: block; margin-bottom: 9px; color: #34405b; font-size: .88rem; font-weight: 700; }
.input-row, .result-row { display: flex; gap: 8px; }
input { min-width: 0; width: 100%; height: 52px; padding: 0 15px; color: #17213a; background: #fff; border: 1px solid #b8c9e8; border-radius: 12px; }
input::placeholder { color: #9aa6ba; }
button { min-width: 116px; height: 52px; padding: 0 17px; color: #fff; background: #155eef; border: 0; border-radius: 12px; font-weight: 750; white-space: nowrap; }
button:hover { background: #0d4dcd; }
button:disabled { cursor: wait; opacity: .65; }
.message { min-height: 1.25em; margin: 9px 0 0; color: #5c6881; font-size: .86rem; }
.error { color: #c72f48; }
.result { margin-top: 25px; padding-top: 23px; border-top: 1px solid #e4ebf8; }
.result > p:first-child { margin: 0 0 9px; color: #34405b; font-size: .88rem; font-weight: 700; }
.result input { color: #155eef; background: #f7faff; font-weight: 700; }
.result button { min-width: 70px; color: #155eef; background: #e6efff; }
.result button:hover { background: #d8e6ff; }
.footnote { margin: 0; color: #7a86a0; font-size: .78rem; text-align: center; }
@media (max-width: 560px) { .shell { width: min(100% - 24px, 720px); padding-top: 24px; } .card { border-radius: 18px; } .input-row { display: grid; } .input-row button { width: 100%; } .result-row { display: grid; } .result button { width: 100%; } }