@font-face {
  font-family: 'Hana2-R';
  src: url('https://cdn.jsdelivr.net/gh/fontbee/font@main/Hana/Hana2-R.woff2') format('woff2');
  font-weight: 400;
  font-style: normal;
}

@font-face {
  font-family: 'Hana2-M';
  src: url('https://cdn.jsdelivr.net/gh/fontbee/font@main/Hana/Hana2-M.woff2') format('woff2');
  font-weight: 500;
  font-style: normal;
}

@font-face {
  font-family: 'Hana2-B';
  src: url('https://cdn.jsdelivr.net/gh/fontbee/font@main/Hana/Hana2-B.woff2') format('woff2');
  font-weight: 700;
  font-style: normal;
}

:root {
  --hana-mint: #00a39f;
  --hana-deep: #008485;
  --hana-accent: #2dc396;
  --bg: #f2f9f9;
  --card-bg: #ffffff;
  --text: #333333;
  --body-text: #555555;
  --muted: #999999;
  --error: #d64545;
  --border: #dbdbdb;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--bg);
  font-family: 'Hana2-M', -apple-system, BlinkMacSystemFont, "Segoe UI", Pretendard, Roboto, sans-serif;
  color: var(--body-text);
  padding: 24px;
}

.card {
  width: 100%;
  max-width: 420px;
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 40px 32px;
  box-shadow: 0 4px 24px rgba(0, 163, 159, 0.10);
  text-align: center;
}

h1 {
  margin: 0 0 8px;
  font-family: 'Hana2-B', -apple-system, sans-serif;
  font-size: 24px;
  font-weight: 700;
  color: var(--hana-mint);
}

.subtitle {
  margin: 0 0 28px;
  color: var(--muted);
  font-size: 14px;
}

#prime-form {
  display: flex;
  gap: 8px;
}

#number-input {
  flex: 1;
  padding: 12px 14px;
  font-family: 'Hana2-M', -apple-system, sans-serif;
  font-size: 16px;
  color: var(--text);
  border: 1.5px solid var(--border);
  border-radius: 10px;
  outline: none;
  transition: border-color 0.15s ease;
}

#number-input:focus {
  border-color: var(--hana-mint);
}

button {
  padding: 12px 20px;
  font-family: 'Hana2-B', -apple-system, sans-serif;
  font-size: 15px;
  font-weight: 700;
  color: #fff;
  background: var(--hana-mint);
  border: none;
  border-radius: 10px;
  cursor: pointer;
  transition: background 0.15s ease;
}

button:hover {
  background: var(--hana-deep);
}

.result {
  margin-top: 24px;
  min-height: 24px;
  font-family: 'Hana2-B', -apple-system, sans-serif;
  font-size: 16px;
  font-weight: 700;
}

.result.prime {
  color: var(--hana-mint);
}

.result.not-prime {
  color: var(--muted);
}

.result.error {
  color: var(--error);
  font-family: 'Hana2-M', -apple-system, sans-serif;
  font-weight: 500;
}

.card.shake {
  animation: shake 0.4s ease;
}

@keyframes shake {
  0%, 100% { transform: translateX(0); }
  20% { transform: translateX(-10px); }
  40% { transform: translateX(9px); }
  60% { transform: translateX(-6px); }
  80% { transform: translateX(4px); }
}

.card.shake-vertical {
  animation: shake-vertical 0.4s ease;
}

@keyframes shake-vertical {
  0%, 100% { transform: translateY(0); }
  20% { transform: translateY(-8px); }
  40% { transform: translateY(7px); }
  60% { transform: translateY(-5px); }
  80% { transform: translateY(3px); }
}