:root {
  color-scheme: light;
  font-family: "Apple SD Gothic Neo", "Noto Sans KR", "Malgun Gothic", sans-serif;
  background: #f5f5f7;
  color: #1c1c1c;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
}

.container {
  max-width: 880px;
  margin: 0 auto;
  padding: 40px 20px 80px;
  display: flex;
  flex-direction: column;
  gap: 24px;
}

header {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

h1 {
  margin: 0;
  font-size: 24px;
}

.subtitle {
  margin: 0;
  font-size: 14px;
  color: #666;
}

.card {
  background: #fff;
  border-radius: 12px;
  padding: 20px;
  border: 1px solid #e0e0e0;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.field {
  display: flex;
  flex-direction: column;
  gap: 6px;
  font-size: 14px;
}

input[type="file"] {
  padding: 10px;
  border: 1px dashed #cfcfcf;
  border-radius: 10px;
  background: #fafafa;
}

.options {
  display: grid;
  gap: 12px;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
}

select,
input[type="number"] {
  padding: 10px;
  border: 1px solid #d6d6d6;
  border-radius: 10px;
  background: #fff;
  font-size: 14px;
}

.toggle {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 14px;
}

.actions {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
}

button {
  border: none;
  border-radius: 8px;
  padding: 10px 14px;
  background: #1c1c1c;
  color: #fff;
  cursor: pointer;
  font-size: 14px;
}

button.secondary {
  background: #f0f0f0;
  color: #1c1c1c;
  border: 1px solid #d8d8d8;
}

button:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

.notice {
  margin: 0;
  font-size: 13px;
  color: #666;
}

.error {
  border-radius: 10px;
  border: 1px solid #f1bcbc;
  background: #fff5f5;
  padding: 12px;
  font-size: 13px;
  color: #a10000;
  line-height: 1.5;
}

#resultText {
  width: 100%;
  border-radius: 10px;
  border: 1px solid #e0e0e0;
  padding: 12px;
  font-size: 13px;
  font-family: "SF Mono", "Menlo", "Consolas", monospace;
  resize: vertical;
}

h2 {
  margin: 0;
  font-size: 16px;
}

@media (max-width: 640px) {
  .container {
    padding: 28px 16px 60px;
  }
}