:root {
  color-scheme: light dark;
  --background: #f9f9f9;
  --text: #000000;
  --heading: #333333;
  --surface: #ffffff;
  --muted: #555555;
  --sensitive: #c62828;
  --button: #0056b3;
  --button-text: #ffffff;
  --disabled: #6e6e6e;
  --disabled-text: #ffffff;
  --border: #767676;
  --drop-background: #f0f0f0;
  --drop-text: #555555;
  --drop-border: #888888;
  --drag-background: #cce5ff;
  --drag-text: #004085;
  --drag-border: #0056b3;
  --focus: #0056b3;
  --link: #0056b3;
}

* {
  box-sizing: border-box;
}

body {
  font-family: sans-serif;
  background: var(--background);
  color: var(--text);
  margin: 0;
  padding: 20px;
  line-height: 1.5;
  overflow-wrap: anywhere;
}

main {
  max-width: 960px;
  margin: 0 auto;
}

.page-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 8px;
}

h1 {
  color: var(--heading);
  font-size: clamp(1.4rem, 4vw, 2rem);
}

/* 英語のほうが語が長いため、切り替えボタンは語中で折り返さない。 */
.lang-button {
  flex-shrink: 0;
  margin-top: 1em;
  padding: 8px 12px;
  font-size: 0.9rem;
  overflow-wrap: normal;
  white-space: nowrap;
}

#metaInfo {
  margin-top: 20px;
  padding: 10px;
  background: var(--surface);
  border: 1px solid var(--border);
  white-space: pre-wrap;
  overflow-wrap: anywhere;
}

#metaInfo:empty {
  display: none;
}

#metaInfo ul {
  margin: 8px 0;
  padding-left: 24px;
}

#metaInfo h3,
.risk-summary {
  margin: 4px 0;
}

.sensitive {
  color: var(--sensitive);
}

button {
  margin-top: 10px;
  padding: 10px;
  font-size: 1rem;
  background-color: var(--button);
  color: var(--button-text);
  border: none;
  cursor: pointer;
  min-height: 44px;
}
button:disabled {
  background-color: var(--disabled);
  color: var(--disabled-text);
  cursor: not-allowed;
}

.drop-zone {
  border: 2px dashed var(--drop-border);
  padding: 30px;
  text-align: center;
  color: var(--drop-text);
  margin-bottom: 15px;
  background-color: var(--drop-background);
  cursor: pointer;
  min-height: 44px;
}
.drop-zone.dragover {
  background-color: var(--drag-background);
  border-color: var(--drag-border);
  color: var(--drag-text);
}

#filenameInput {
  padding: 5px;
  font-size: 1rem;
  width: 200px;
  max-width: 100%;
  min-height: 44px;
  border: 1px solid var(--border);
  background: var(--surface);
  color: var(--text);
}

#fileInput {
  display: block;
  font-size: 16px;
  max-width: 100%;
  min-height: 44px;
  color: var(--text);
}

#fileInput::file-selector-button {
  min-height: 44px;
  padding: 8px;
  border: 1px solid var(--border);
  background: var(--surface);
  color: var(--text);
  font: inherit;
}

fieldset {
  min-width: 0;
  margin: 20px 0 0;
  border: 1px solid var(--border);
  background: var(--surface);
}

.method-option {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 8px 0;
  min-height: 44px;
  cursor: pointer;
}

.method-option input {
  flex-shrink: 0;
  accent-color: var(--button);
}

.method-option small {
  display: block;
  color: var(--muted);
}

.filename-row {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 8px;
}

#resultInfo {
  white-space: pre-wrap;
  overflow-wrap: anywhere;
}

.notice {
  color: var(--muted);
  font-size: 0.9rem;
}

a {
  color: var(--link);
}

.site-footer {
  margin-top: 2em;
  font-size: 0.9em;
  text-align: center;
}

.site-footer a {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
}

:focus-visible {
  outline: 2px solid var(--focus);
  outline-offset: 3px;
}

@media (prefers-color-scheme: dark) {
  :root {
    --background: #121212;
    --text: #e8e8e8;
    --heading: #e8e8e8;
    --surface: #1e1e1e;
    --muted: #b8b8b8;
    --sensitive: #ff8a80;
    --button: #3d8bfd;
    --button-text: #121212;
    --disabled: #9e9e9e;
    --disabled-text: #121212;
    --border: #6f6f6f;
    --drop-background: #1e1e1e;
    --drop-text: #b8b8b8;
    --drop-border: #6f6f6f;
    --drag-background: #1e1e1e;
    --drag-text: #e8e8e8;
    --drag-border: #8ab4f8;
    --focus: #8ab4f8;
    --link: #8ab4f8;
  }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    transition: none;
  }
}