:root {
  --bg: #0f0f10;
  --panel-bg: #1a1a1c;
  --panel-border: #2c2c2e;
  --text-primary: #ececec;
  --text-secondary: #9a9a9d;
  --accent: #10a37f;
  --accent-hover: #0d8c6d;
  --error-bg: #3a1414;
  --error-border: #7a2b2b;
  --error-text: #ff9b9b;
  --radius: 12px;
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, sans-serif;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--text-primary);
  font-family: var(--font);
  min-height: 100vh;
}

.app {
  max-width: 900px;
  margin: 0 auto;
  padding: 32px 20px 60px;
  display: flex;
  flex-direction: column;
  gap: 24px;
}

.app-header {
  display: flex;
  flex-direction: column;
  gap: 4px;
  align-items: center;
  text-align: center;
}

.logo {
  font-size: 22px;
  font-weight: 600;
  display: flex;
  align-items: center;
  gap: 8px;
  letter-spacing: 0.5px;
}

.logo-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--accent);
  display: inline-block;
}

.subtitle {
  color: var(--text-secondary);
  font-size: 14px;
}

.main {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.panel {
  background: var(--panel-bg);
  border: 1px solid var(--panel-border);
  border-radius: var(--radius);
  padding: 18px;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.panel-label {
  font-size: 13px;
  color: var(--text-secondary);
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.prompt-textarea {
  width: 100%;
  resize: vertical;
  min-height: 140px;
  background: #0f0f10;
  border: 1px solid var(--panel-border);
  border-radius: 8px;
  color: var(--text-primary);
  font-family: var(--font);
  font-size: 15px;
  padding: 12px 14px;
  line-height: 1.5;
}

.prompt-textarea:focus {
  outline: none;
  border-color: var(--accent);
}

.input-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.char-counter {
  font-size: 12px;
  color: var(--text-secondary);
}

.btn {
  border: none;
  border-radius: 8px;
  padding: 10px 18px;
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.15s ease, opacity 0.15s ease;
}

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

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

.btn-primary:hover:not(:disabled) {
  background: var(--accent-hover);
}

.btn-secondary {
  background: transparent;
  color: var(--text-primary);
  border: 1px solid var(--panel-border);
}

.btn-secondary:hover:not(:disabled) {
  border-color: var(--accent);
  color: var(--accent);
}

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

.btn-danger:hover:not(:disabled) {
  background: var(--error-border);
}

.output-panel-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.output-area {
  position: relative;
  min-height: 200px;
  background: #0f0f10;
  border: 1px solid var(--panel-border);
  border-radius: 8px;
  padding: 16px;
}

.output-text {
  margin: 0;
  white-space: pre-wrap;
  word-wrap: break-word;
  font-family: var(--font);
  font-size: 15px;
  line-height: 1.6;
  color: var(--text-primary);
}

.placeholder {
  color: var(--text-secondary);
  font-size: 14px;
}

.output-text:empty + .error-box.hidden + .placeholder {
  display: block;
}

.output-text:not(:empty) ~ .placeholder,
.output-area.has-content .placeholder {
  display: none;
}

.loading-indicator {
  display: flex;
  gap: 6px;
  align-items: center;
  padding: 4px 0;
}

.loading-indicator.hidden {
  display: none;
}

.dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--text-secondary);
  animation: blink 1.2s infinite ease-in-out;
}

.dot:nth-child(2) {
  animation-delay: 0.2s;
}

.dot:nth-child(3) {
  animation-delay: 0.4s;
}

@keyframes blink {
  0%, 80%, 100% { opacity: 0.2; }
  40% { opacity: 1; }
}

.error-box {
  margin-top: 10px;
  background: var(--error-bg);
  border: 1px solid var(--error-border);
  color: var(--error-text);
  border-radius: 8px;
  padding: 10px 14px;
  font-size: 14px;
}

.error-box.hidden {
  display: none;
}

.typing-cursor::after {
  content: "▍";
  animation: blink 1s infinite step-start;
  color: var(--accent);
}

.hidden {
  display: none;
}