/* ChatGPT.ag — modern dark chat UI */
:root {
  --bg: #0b0f19;
  --bg-elevated: #121826;
  --bg-input: #1a2234;
  --border: #243049;
  --text: #e8eef8;
  --text-muted: #8b9bb8;
  --accent: #6c8cff;
  --accent-hover: #8aa4ff;
  --accent-soft: rgba(108, 140, 255, 0.15);
  --user-bubble: #2a3a66;
  --assistant-bubble: #161e2e;
  --danger: #ff6b7a;
  --success: #3dd68c;
  --radius: 16px;
  --radius-sm: 10px;
  --shadow: 0 8px 32px rgba(0, 0, 0, 0.35);
  --font: "Segoe UI", system-ui, -apple-system, BlinkMacSystemFont, "Helvetica Neue", Arial, sans-serif;
  --mono: ui-monospace, "Cascadia Code", "SF Mono", Consolas, monospace;
  --header-h: 64px;
  --footer-h: auto;
  --max-w: 820px;
}

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

html, body {
  margin: 0;
  padding: 0;
  height: 100%;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font);
  font-size: 16px;
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
}

body {
  display: flex;
  flex-direction: column;
  min-height: 100dvh;
  background:
    radial-gradient(1200px 600px at 10% -10%, rgba(108, 140, 255, 0.18), transparent 55%),
    radial-gradient(900px 500px at 90% 0%, rgba(61, 214, 140, 0.08), transparent 50%),
    var(--bg);
}

a {
  color: var(--accent);
  text-decoration: none;
}
a:hover {
  color: var(--accent-hover);
  text-decoration: underline;
}

/* Header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  height: var(--header-h);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 1.25rem;
  border-bottom: 1px solid var(--border);
  background: rgba(11, 15, 25, 0.85);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
}

.brand {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  min-width: 0;
}

.brand-mark {
  width: 36px;
  height: 36px;
  border-radius: 10px;
  background: linear-gradient(135deg, #6c8cff, #3dd68c);
  display: grid;
  place-items: center;
  font-weight: 700;
  font-size: 0.85rem;
  color: #0b0f19;
  flex-shrink: 0;
  box-shadow: 0 0 0 1px rgba(255,255,255,0.12), 0 4px 16px rgba(108,140,255,0.35);
}

.brand-text {
  display: flex;
  flex-direction: column;
  min-width: 0;
}

.brand-name {
  font-weight: 700;
  font-size: 1.05rem;
  letter-spacing: -0.02em;
  white-space: nowrap;
}

.brand-tag {
  font-size: 0.75rem;
  color: var(--text-muted);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.btn {
  appearance: none;
  border: 1px solid var(--border);
  background: var(--bg-elevated);
  color: var(--text);
  border-radius: 999px;
  padding: 0.45rem 0.9rem;
  font-size: 0.875rem;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.15s, border-color 0.15s, color 0.15s;
}
.btn:hover {
  border-color: var(--accent);
  color: var(--accent-hover);
}
.btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}
.btn-primary {
  background: var(--accent);
  border-color: transparent;
  color: #0b0f19;
}
.btn-primary:hover:not(:disabled) {
  background: var(--accent-hover);
  color: #0b0f19;
}
.btn-icon {
  width: 40px;
  height: 40px;
  padding: 0;
  display: grid;
  place-items: center;
  border-radius: 12px;
}

/* Main layout */
.main {
  flex: 1;
  display: flex;
  flex-direction: column;
  width: 100%;
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 1rem;
  min-height: 0;
}

/* Welcome / empty state */
.welcome {
  flex: 1;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  text-align: center;
  padding: 2rem 0.5rem 1rem;
  gap: 1.25rem;
}

.welcome.hidden {
  display: none;
}

.welcome h1 {
  margin: 0;
  font-size: clamp(1.6rem, 4vw, 2.1rem);
  letter-spacing: -0.03em;
  font-weight: 750;
}

.welcome p {
  margin: 0;
  max-width: 36rem;
  color: var(--text-muted);
  font-size: 1.05rem;
}

.badge-free {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.35rem 0.75rem;
  border-radius: 999px;
  background: var(--accent-soft);
  color: var(--accent-hover);
  font-size: 0.8rem;
  font-weight: 600;
  border: 1px solid rgba(108, 140, 255, 0.25);
}

.prompts {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 0.75rem;
  width: 100%;
  max-width: 640px;
  margin-top: 0.5rem;
}

.prompt-card {
  text-align: left;
  padding: 0.9rem 1rem;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border);
  background: var(--bg-elevated);
  color: var(--text);
  cursor: pointer;
  font-size: 0.9rem;
  transition: border-color 0.15s, transform 0.15s, background 0.15s;
}
.prompt-card:hover {
  border-color: var(--accent);
  background: var(--accent-soft);
  transform: translateY(-1px);
}
.prompt-card strong {
  display: block;
  margin-bottom: 0.25rem;
  font-size: 0.85rem;
  color: var(--accent-hover);
}

/* Chat messages */
.chat {
  flex: 1;
  overflow-y: auto;
  padding: 1.25rem 0 0.5rem;
  display: flex;
  flex-direction: column;
  gap: 1rem;
  scroll-behavior: smooth;
  min-height: 0;
}

.chat:empty,
.chat.hidden {
  display: none;
}

.msg {
  display: flex;
  gap: 0.75rem;
  max-width: 100%;
  animation: fadeIn 0.25s ease;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(6px); }
  to { opacity: 1; transform: none; }
}

.msg-avatar {
  width: 32px;
  height: 32px;
  border-radius: 10px;
  flex-shrink: 0;
  display: grid;
  place-items: center;
  font-size: 0.7rem;
  font-weight: 700;
  margin-top: 0.15rem;
}

.msg-user .msg-avatar {
  background: var(--user-bubble);
  color: #c5d4ff;
  order: 2;
}

.msg-assistant .msg-avatar {
  background: linear-gradient(135deg, #6c8cff, #3dd68c);
  color: #0b0f19;
}

.msg-user {
  flex-direction: row-reverse;
}

.msg-bubble {
  padding: 0.85rem 1.05rem;
  border-radius: var(--radius);
  max-width: min(100%, 640px);
  white-space: pre-wrap;
  word-wrap: break-word;
  overflow-wrap: anywhere;
  font-size: 0.95rem;
  line-height: 1.55;
}

.msg-user .msg-bubble {
  background: var(--user-bubble);
  border-bottom-right-radius: 4px;
}

.msg-assistant .msg-bubble {
  background: var(--assistant-bubble);
  border: 1px solid var(--border);
  border-bottom-left-radius: 4px;
}

.msg-bubble code {
  font-family: var(--mono);
  font-size: 0.85em;
  background: rgba(0,0,0,0.35);
  padding: 0.1em 0.35em;
  border-radius: 4px;
}

.msg-bubble pre {
  margin: 0.75rem 0 0;
  padding: 0.85rem;
  overflow-x: auto;
  background: rgba(0,0,0,0.4);
  border-radius: var(--radius-sm);
  font-family: var(--mono);
  font-size: 0.82rem;
}

.msg-error .msg-bubble {
  border-color: rgba(255, 107, 122, 0.4);
  color: #ffb4bc;
}

.typing {
  display: inline-flex;
  gap: 5px;
  align-items: center;
  padding: 0.25rem 0;
}
.typing span {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--text-muted);
  animation: bounce 1.2s infinite ease-in-out;
}
.typing span:nth-child(2) { animation-delay: 0.15s; }
.typing span:nth-child(3) { animation-delay: 0.3s; }

@keyframes bounce {
  0%, 80%, 100% { transform: translateY(0); opacity: 0.4; }
  40% { transform: translateY(-5px); opacity: 1; }
}

/* Composer */
.composer-wrap {
  position: sticky;
  bottom: 0;
  padding: 0.75rem 0 1rem;
  background: linear-gradient(to top, var(--bg) 70%, transparent);
}

.composer {
  display: flex;
  align-items: flex-end;
  gap: 0.6rem;
  padding: 0.65rem 0.65rem 0.65rem 1rem;
  background: var(--bg-input);
  border: 1px solid var(--border);
  border-radius: calc(var(--radius) + 4px);
  box-shadow: var(--shadow);
  transition: border-color 0.15s, box-shadow 0.15s;
}

.composer:focus-within {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-soft), var(--shadow);
}

.composer textarea {
  flex: 1;
  border: none;
  outline: none;
  resize: none;
  background: transparent;
  color: var(--text);
  font-family: inherit;
  font-size: 1rem;
  line-height: 1.45;
  max-height: 160px;
  min-height: 24px;
  padding: 0.35rem 0;
}

.composer textarea::placeholder {
  color: var(--text-muted);
}

.send-btn {
  width: 44px;
  height: 44px;
  border: none;
  border-radius: 12px;
  background: var(--accent);
  color: #0b0f19;
  cursor: pointer;
  display: grid;
  place-items: center;
  flex-shrink: 0;
  transition: background 0.15s, transform 0.1s;
}
.send-btn:hover:not(:disabled) {
  background: var(--accent-hover);
}
.send-btn:active:not(:disabled) {
  transform: scale(0.96);
}
.send-btn:disabled {
  opacity: 0.45;
  cursor: not-allowed;
}

.composer-hint {
  margin: 0.5rem 0 0;
  text-align: center;
  font-size: 0.75rem;
  color: var(--text-muted);
}

/* Footer */
.site-footer {
  padding: 0.75rem 1.25rem 1.25rem;
  text-align: center;
  font-size: 0.75rem;
  color: var(--text-muted);
  border-top: 1px solid transparent;
  max-width: var(--max-w);
  margin: 0 auto;
  width: 100%;
}

.site-footer p {
  margin: 0.25rem 0;
}

/* Status toast */
.toast {
  position: fixed;
  bottom: 5.5rem;
  left: 50%;
  transform: translateX(-50%) translateY(12px);
  background: #1e293b;
  border: 1px solid var(--border);
  color: var(--text);
  padding: 0.65rem 1rem;
  border-radius: 999px;
  font-size: 0.85rem;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.2s, transform 0.2s;
  z-index: 50;
  max-width: min(90vw, 420px);
  text-align: center;
  box-shadow: var(--shadow);
}
.toast.show {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}
.toast.error {
  border-color: rgba(255, 107, 122, 0.5);
  color: #ffb4bc;
}

@media (max-width: 560px) {
  .brand-tag { display: none; }
  .prompts { grid-template-columns: 1fr; }
  .site-header { padding: 0 0.85rem; }
  .main { padding: 0 0.75rem; }
  .btn-text { display: none; }
}