:root {
  --bg: #0f1117;
  --bg-card: #1a1d29;
  --bg-card-hover: #222639;
  --border: #2a2e42;
  --text: #e4e6ef;
  --text-muted: #8a8fa3;
  --accent: #4f8cff;
  --accent-hover: #6ba1ff;
  --green: #4ade80;
  --red: #f87171;
  --radius: 14px;
  --shadow: 0 4px 24px rgba(0,0,0,0.3);
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
  min-height: 100vh;
  line-height: 1.6;
}

.app-header {
  padding: 2rem 2rem 1rem;
  border-bottom: 1px solid var(--border);
}

.app-header h1 {
  font-size: 1.6rem;
  font-weight: 700;
  letter-spacing: -0.02em;
}

.app-header p {
  color: var(--text-muted);
  font-size: 0.9rem;
  margin-top: 0.3rem;
}

.app-container {
  max-width: 960px;
  margin: 0 auto;
  padding: 0 2rem 3rem;
}

.tools-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 1.2rem;
  margin-top: 2rem;
}

.tool-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.5rem;
  text-decoration: none;
  color: var(--text);
  transition: all 0.2s ease;
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
  position: relative;
}

.tool-card:hover {
  background: var(--bg-card-hover);
  border-color: var(--accent);
  transform: translateY(-2px);
  box-shadow: var(--shadow);
}

.tool-card .tool-icon {
  font-size: 2rem;
  line-height: 1;
}

.tool-card .tool-name {
  font-size: 1.1rem;
  font-weight: 600;
}

.tool-card .tool-desc {
  font-size: 0.85rem;
  color: var(--text-muted);
}

.tool-card .tool-badge {
  position: absolute;
  top: 1rem;
  right: 1rem;
  font-size: 0.7rem;
  padding: 0.2rem 0.6rem;
  border-radius: 20px;
  background: rgba(74, 222, 128, 0.15);
  color: var(--green);
  border: 1px solid rgba(74, 222, 128, 0.3);
}

.tool-card .tool-badge.coming {
  background: rgba(138, 143, 163, 0.15);
  color: var(--text-muted);
  border-color: rgba(138, 143, 163, 0.3);
}

.back-link {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  color: var(--text-muted);
  text-decoration: none;
  font-size: 0.9rem;
  margin-bottom: 1.5rem;
  transition: color 0.15s;
}

.back-link:hover {
  color: var(--accent);
}

.tool-page {
  max-width: 720px;
  margin: 0 auto;
  padding: 0 2rem 3rem;
}

.drop-zone {
  border: 2px dashed var(--border);
  border-radius: var(--radius);
  padding: 2.5rem 2rem;
  text-align: center;
  cursor: pointer;
  transition: all 0.2s;
  background: var(--bg-card);
}

.drop-zone:hover, .drop-zone.dragover {
  border-color: var(--accent);
  background: var(--bg-card-hover);
}

.drop-zone .dz-icon {
  font-size: 2.5rem;
  margin-bottom: 0.5rem;
}

.drop-zone .dz-text {
  color: var(--text);
  font-weight: 500;
}

.drop-zone .dz-hint {
  color: var(--text-muted);
  font-size: 0.8rem;
  margin-top: 0.3rem;
}

.result-area {
  margin-top: 1.5rem;
}

.result-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 0.8rem;
}

.result-header h3 {
  font-size: 1rem;
  font-weight: 600;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.6rem 1.2rem;
  border-radius: 8px;
  border: none;
  font-size: 0.9rem;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.15s;
  text-decoration: none;
}

.btn-primary {
  background: var(--accent);
  color: white;
}

.btn-primary:hover {
  background: var(--accent-hover);
}

.btn-primary:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

.btn-secondary {
  background: var(--bg-card);
  color: var(--text);
  border: 1px solid var(--border);
}

.btn-secondary:hover {
  border-color: var(--accent);
}

.result-output {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.2rem;
  font-family: "SF Mono", "Cascadia Code", "Fira Code", Consolas, monospace;
  font-size: 0.85rem;
  white-space: pre-wrap;
  word-break: break-word;
  max-height: 480px;
  overflow-y: auto;
  line-height: 1.5;
}

.status-msg {
  padding: 0.8rem 1rem;
  border-radius: 8px;
  font-size: 0.9rem;
  margin-top: 1rem;
  display: none;
}

.status-msg.show { display: block; }
.status-msg.error { background: rgba(248, 113, 113, 0.1); color: var(--red); border: 1px solid rgba(248, 113, 113, 0.3); }
.status-msg.success { background: rgba(74, 222, 128, 0.1); color: var(--green); border: 1px solid rgba(74, 222, 128, 0.3); }
.status-msg.loading { background: rgba(79, 140, 255, 0.1); color: var(--accent); border: 1px solid rgba(79, 140, 255, 0.3); }

.ext-chips {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  margin-top: 1rem;
}

.ext-chip {
  font-size: 0.75rem;
  padding: 0.2rem 0.6rem;
  border-radius: 6px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  color: var(--text-muted);
}

.loading-spinner {
  display: inline-block;
  width: 16px;
  height: 16px;
  border: 2px solid var(--border);
  border-top-color: var(--accent);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

@media (max-width: 600px) {
  .app-header { padding: 1.5rem 1rem 0.8rem; }
  .app-container, .tool-page { padding: 0 1rem 2rem; }
  .tools-grid { grid-template-columns: 1fr; }
}