/* Gruvbox dark palette */
:root {
  --bg:        #282828;
  --bg-soft:   #32302f;
  --bg-card:   #3c3836;
  --bg-input:  #504945;
  --fg:        #ebdbb2;
  --fg-dim:    #a89984;
  --fg-faint:  #7c6f64;
  --accent:    #FA7248;
  --accent-dim:#d65d38;
  --green:     #b8bb26;
  --yellow:    #fabd2f;
  --aqua:      #8ec07c;
  --blue:      #83a598;

  --font-serif: Georgia, 'Times New Roman', serif;
  --font-mono:  'IBM Plex Mono', 'Courier New', monospace;

  --radius: 8px;
  --max-width: 680px;
}

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

html {
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
}

body {
  background: var(--bg);
  color: var(--fg);
  font-family: var(--font-mono);
  font-size: 0.9rem;
  line-height: 1.6;
  min-height: 100dvh;
  display: flex;
  flex-direction: column;
}

/* Layout */
.container {
  width: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 2rem 1.5rem;
  display: flex;
  flex-direction: column;
  min-height: 100dvh;
}

/* Header */
header {
  text-align: center;
  margin-bottom: 2rem;
  padding-bottom: 1.5rem;
  border-bottom: 1px solid var(--bg-input);
}

.logo {
  font-size: 2rem;
  color: var(--accent);
  margin-bottom: 0.4rem;
  line-height: 1;
}

h1 {
  font-family: var(--font-serif);
  font-weight: 400;
  font-size: 2.4rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--fg);
  line-height: 1.1;
  margin-bottom: 0.35rem;
}

.subtitle {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--fg-faint);
  margin-bottom: 0.3rem;
}

.byline {
  font-size: 0.75rem;
  color: var(--fg-faint);
}

.byline a {
  color: var(--accent);
  text-decoration: none;
}

.byline a:hover {
  text-decoration: underline;
}

/* Chat area */
.chat {
  flex: 1;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
  padding-bottom: 1.5rem;
}

.message {
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
}

.message-label {
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--fg-faint);
  font-weight: 500;
}

.message.user .message-label {
  text-align: right;
}

.message-body {
  background: var(--bg-card);
  border-radius: var(--radius);
  padding: 0.85rem 1rem;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.message.user .message-body {
  background: var(--bg-input);
  margin-left: 3rem;
}

.message.assistant .message-body {
  margin-right: 3rem;
}

/* Thinking state */
.thinking-body {
  background: var(--bg-card);
  border-radius: var(--radius);
  padding: 0.85rem 1rem;
  margin-right: 3rem;
}

.thinking-text {
  color: var(--fg-dim);
  font-style: italic;
  font-size: 0.85rem;
}

.thinking-spinner {
  color: var(--accent);
}


/* Input area */
.input-area {
  display: flex;
  gap: 0.75rem;
  align-items: flex-end;
  padding-top: 1rem;
  border-top: 1px solid var(--bg-input);
}

textarea {
  flex: 1;
  background: var(--bg-soft);
  color: var(--fg);
  border: 1px solid var(--bg-input);
  border-radius: var(--radius);
  padding: 0.7rem 0.9rem;
  font-family: var(--font-mono);
  font-size: 0.9rem;
  line-height: 1.5;
  resize: none;
  outline: none;
  overflow: hidden;
  transition: border-color 0.2s;
  max-height: 120px;
}

textarea::placeholder {
  color: var(--fg-faint);
}

textarea:focus {
  border-color: var(--accent);
}

button {
  background: var(--accent);
  color: var(--bg);
  border: 1px solid transparent;
  border-radius: var(--radius);
  padding: 0.7rem 1.5rem;
  font-family: var(--font-mono);
  font-size: 0.9rem;
  line-height: 1.5;
  font-weight: 500;
  cursor: pointer;
  transition: background 0.2s, transform 0.1s;
  white-space: nowrap;
}

button:hover {
  background: var(--accent-dim);
}

button:active {
  transform: scale(0.97);
}

button:disabled {
  opacity: 0.4;
  cursor: not-allowed;
  transform: none;
}

/* Footer */
footer {
  margin-top: 1rem;
  padding-top: 1rem;
  border-top: 1px solid var(--bg-input);
  text-align: center;
  font-size: 0.65rem;
  color: var(--fg-faint);
  line-height: 1.5;
}

.footer-note {
  font-style: italic;
}

/* Scrollbar */
.chat::-webkit-scrollbar {
  width: 6px;
}

.chat::-webkit-scrollbar-track {
  background: transparent;
}

.chat::-webkit-scrollbar-thumb {
  background: var(--bg-input);
  border-radius: 3px;
}

/* Responsive */
@media (max-width: 520px) {
  .container {
    padding: 1.25rem 1rem;
  }

  h1 {
    font-size: 2.2rem;
  }

  .message.user .message-body {
    margin-left: 1.5rem;
  }

  .message.assistant .message-body,
  .thinking-body {
    margin-right: 1.5rem;
  }

  .answer-text {
    font-size: 2.4rem;
  }
}