:root {
  --bg: #f3eadf;
  --panel: rgba(255, 252, 246, 0.92);
  --panel-border: rgba(60, 84, 74, 0.14);
  --ink: #203036;
  --muted: #647076;
  --accent: #0f766e;
  --accent-strong: #0a5c56;
  --accent-soft: rgba(15, 118, 110, 0.12);
  --warning: #a16207;
  --warning-bg: rgba(245, 158, 11, 0.12);
  --error: #b42318;
  --error-bg: rgba(228, 72, 72, 0.12);
  --success: #166534;
  --success-bg: rgba(34, 197, 94, 0.14);
  --shadow: 0 24px 80px rgba(35, 46, 52, 0.12);
  --radius-xl: 28px;
  --radius-lg: 18px;
  --radius-md: 12px;
  --mono: "SFMono-Regular", "Consolas", "Liberation Mono", monospace;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: "Noto Sans TC", "PingFang TC", "Microsoft JhengHei", sans-serif;
  color: var(--ink);
  background:
    radial-gradient(circle at top left, rgba(15, 118, 110, 0.16), transparent 34%),
    radial-gradient(circle at top right, rgba(173, 109, 54, 0.14), transparent 28%),
    linear-gradient(180deg, #efe2d1 0%, var(--bg) 48%, #f8f2ea 100%);
}

.app-shell {
  width: min(960px, calc(100vw - 32px));
  margin: 0 auto;
  padding: 56px 0 72px;
}

.hero {
  margin-bottom: 24px;
}

.hero h1 {
  margin: 0;
  font-size: clamp(2rem, 4vw, 3.5rem);
  line-height: 1.05;
}

.hero-copy {
  width: min(60ch, 100%);
  margin: 16px 0 0;
  color: var(--muted);
  font-size: 1rem;
  line-height: 1.7;
}

.tool-card,
.panel {
  backdrop-filter: blur(14px);
  background: var(--panel);
  border: 1px solid var(--panel-border);
  box-shadow: var(--shadow);
}

.tool-card {
  padding: 24px;
  border-radius: var(--radius-xl);
  margin-top: 24px;
}

.drop-zone {
  width: 100%;
  border: 2px dashed rgba(15, 118, 110, 0.28);
  border-radius: 22px;
  background:
    linear-gradient(180deg, rgba(255, 255, 255, 0.8), rgba(246, 252, 250, 0.9)),
    var(--accent-soft);
  color: var(--ink);
  padding: 40px 20px;
  text-align: center;
  cursor: pointer;
  transition: transform 180ms ease, border-color 180ms ease, box-shadow 180ms ease, background 180ms ease;
}

.drop-zone:hover,
.drop-zone:focus-visible {
  transform: translateY(-1px);
  border-color: rgba(15, 118, 110, 0.56);
  box-shadow: 0 16px 32px rgba(15, 118, 110, 0.14);
  outline: none;
}

.drop-zone.drag-over {
  border-color: var(--accent);
  background:
    linear-gradient(180deg, rgba(235, 253, 249, 0.96), rgba(247, 255, 253, 0.98)),
    rgba(15, 118, 110, 0.16);
}

.drop-zone-title,
.drop-zone-subtitle {
  display: block;
}

.drop-zone-title {
  font-size: 1.2rem;
  font-weight: 800;
}

.drop-zone-subtitle {
  margin-top: 8px;
  color: var(--muted);
  font-size: 0.96rem;
}

.status {
  margin: 20px 0 0;
  padding: 14px 16px;
  border-radius: var(--radius-md);
  font-weight: 600;
  background: rgba(15, 118, 110, 0.08);
  color: var(--ink);
}

.status[data-type="success"] {
  background: var(--success-bg);
  color: var(--success);
}

.status[data-type="warning"] {
  background: var(--warning-bg);
  color: var(--warning);
}

.status[data-type="error"] {
  background: var(--error-bg);
  color: var(--error);
}

.panel {
  margin-top: 18px;
  border-radius: var(--radius-lg);
  padding: 20px;
}

.panel-header {
  margin-bottom: 16px;
}

.panel-header h2 {
  margin: 0;
  font-size: 1rem;
}

.summary-grid {
  margin: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px 20px;
}

.summary-grid div {
  padding: 14px 16px;
  border-radius: 14px;
  background: rgba(255, 255, 255, 0.72);
  border: 1px solid rgba(60, 84, 74, 0.08);
}

.summary-grid dt {
  margin: 0 0 6px;
  color: var(--muted);
  font-size: 0.86rem;
}

.summary-grid dd {
  margin: 0;
  font-size: 1rem;
  font-weight: 700;
  word-break: break-word;
}

.actions {
  margin-top: 18px;
}

.download-button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 0 20px;
  border-radius: 999px;
  background: linear-gradient(135deg, var(--accent), var(--accent-strong));
  color: #f8fffd;
  font-weight: 800;
  text-decoration: none;
  box-shadow: 0 14px 26px rgba(15, 118, 110, 0.2);
}

.download-button:hover,
.download-button:focus-visible {
  outline: none;
  filter: brightness(1.02);
}

.preview-content {
  margin: 0;
  max-height: 420px;
  overflow: auto;
  padding: 18px;
  border-radius: 14px;
  background: #182126;
  color: #edf6f5;
  font-family: var(--mono);
  font-size: 0.9rem;
  line-height: 1.65;
  white-space: pre-wrap;
  word-break: break-word;
}

@media (max-width: 720px) {
  .app-shell {
    width: min(100vw - 20px, 960px);
    padding: 32px 0 48px;
  }

  .tool-card {
    padding: 18px;
    border-radius: 22px;
  }

  .summary-grid {
    grid-template-columns: 1fr;
  }
}

.senders-details {
  cursor: pointer;
  outline: none;
}

.senders-details summary {
  outline: none;
  color: var(--accent);
  transition: color 150ms ease;
}

.senders-details summary:hover {
  color: var(--accent-strong);
}

.senders-details[open] summary {
  margin-bottom: 8px;
}

.senders-list {
  font-size: 0.88rem;
  font-weight: 500;
  color: var(--muted);
  max-height: 120px;
  overflow-y: auto;
  padding: 8px 12px;
  border-radius: 8px;
  background: rgba(15, 118, 110, 0.04);
  border: 1px solid rgba(15, 118, 110, 0.08);
  line-height: 1.5;
  text-align: left;
}


.tool-card h2 {
  margin: 0 0 16px;
  font-size: 1.15rem;
  color: var(--accent-strong);
  display: flex;
  align-items: center;
  gap: 10px;
}

.tool-card h2 svg {
  flex-shrink: 0;
  stroke: var(--accent);
}

.instructions-list {
  margin: 0;
  padding-left: 20px;
  color: var(--muted);
  font-size: 0.94rem;
  line-height: 1.7;
}

.instructions-list li {
  margin-bottom: 12px;
}

.instructions-list li:last-child {
  margin-bottom: 0;
}

.instructions-list strong {
  color: var(--ink);
}

.card-content {
  color: var(--muted);
  font-size: 0.94rem;
  line-height: 1.7;
}

.card-content p {
  margin: 0 0 12px;
}

.card-content p:last-child {
  margin: 0;
}

.card-content strong {
  color: var(--ink);
}

.card-subtitle {
  color: var(--muted);
  font-size: 0.94rem;
  margin: 0 0 20px;
}

.prompts-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 20px;
}

.prompt-item {
  padding: 16px;
  border-radius: var(--radius-md);
  background: rgba(255, 255, 255, 0.6);
  border: 1px solid rgba(60, 84, 74, 0.06);
}

.prompt-item h3 {
  margin: 0 0 10px;
  font-size: 0.96rem;
  color: var(--ink);
}

.prompt-item blockquote {
  margin: 0;
  padding: 10px 12px;
  background: rgba(15, 118, 110, 0.04);
  border-left: 3px solid var(--accent);
  border-radius: 0 6px 6px 0;
  color: var(--muted);
  font-size: 0.88rem;
  line-height: 1.6;
}