:root {
  color-scheme: light;
  --bg-top: #f5ecd8;
  --bg-bottom: #dce8f5;
  --panel: rgba(250, 248, 243, 0.9);
  --panel-border: rgba(41, 55, 77, 0.12);
  --shadow: 0 24px 60px rgba(54, 67, 87, 0.14);
  --text: #1f2a37;
  --muted: #5f6c7b;
  --accent: #b85c38;
  --accent-dark: #8d3f22;
  --user-bg: #fff9f0;
  --assistant-bg: #f5f9ff;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: "BIZ UDPGothic", "Yu Gothic UI", "Hiragino Sans", sans-serif;
  color: var(--text);
  background:
    radial-gradient(circle at top right, rgba(184, 92, 56, 0.14), transparent 34%),
    radial-gradient(circle at left 20%, rgba(52, 128, 191, 0.12), transparent 30%),
    linear-gradient(160deg, var(--bg-top), var(--bg-bottom));
}

.shell {
  width: min(1180px, calc(100% - 24px));
  margin: 0 auto;
  padding: 28px 0 32px;
}

.panel {
  border: 1px solid var(--panel-border);
  border-radius: 24px;
  background: var(--panel);
  backdrop-filter: blur(12px);
  box-shadow: var(--shadow);
}

.hero {
  padding: 26px 24px 20px;
}

.workspace {
  margin-top: 18px;
  display: grid;
  gap: 18px;
  grid-template-columns: minmax(260px, 300px) minmax(0, 1fr);
}

.sidebar,
.chat-panel {
  padding: 20px;
}

.debate-panel {
  margin-top: 18px;
  padding: 20px;
}

.eyebrow {
  margin: 0 0 8px;
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--accent);
}

h1,
h2 {
  margin: 0;
}

h1 {
  font-size: clamp(2rem, 5vw, 3.2rem);
  line-height: 1.08;
}

.chat-title {
  font-size: clamp(1.1rem, 2vw, 1.5rem);
  line-height: 1.25;
}

.lede {
  margin: 14px 0 0;
  max-width: 42rem;
  color: var(--muted);
  line-height: 1.7;
}

.sidebar-head,
.toolbar,
.actions {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}

.provider-row {
  margin-top: 14px;
  display: flex;
  align-items: center;
  gap: 12px;
}

.button-row {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
}

.chat-list {
  margin-top: 14px;
  display: grid;
  gap: 10px;
}

.chat-item {
  display: grid;
  gap: 6px;
  grid-template-columns: minmax(0, 1fr) auto;
  align-items: center;
  padding: 10px;
  border-radius: 18px;
  background: rgba(255, 255, 255, 0.56);
  border: 1px solid rgba(41, 55, 77, 0.08);
}

.chat-switch,
.chat-delete {
  width: 100%;
}

.chat-switch {
  grid-column: 1 / 2;
  justify-self: start;
  text-align: left;
  background: transparent;
  color: inherit;
  padding: 10px 12px;
}

.chat-switch.active {
  background: rgba(184, 92, 56, 0.14);
  color: var(--accent-dark);
}

.chat-delete {
  grid-column: 2 / 3;
  min-width: auto;
  padding: 8px 12px;
  background: rgba(41, 55, 77, 0.08);
  color: var(--muted);
}

.chat-meta {
  grid-column: 1 / 3;
  font-size: 0.82rem;
  color: var(--muted);
  padding: 0 12px 2px;
}

.messages {
  margin-top: 12px;
  min-height: 360px;
  max-height: 58vh;
  padding: 10px;
  overflow-y: auto;
  border-radius: 20px;
  background: rgba(255, 255, 255, 0.62);
  border: 1px solid rgba(41, 55, 77, 0.08);
}

.empty-state {
  margin: 0;
  padding: 18px;
  color: var(--muted);
}

.message {
  margin: 0 0 12px;
  padding: 14px 16px;
  border-radius: 18px;
  border: 1px solid rgba(41, 55, 77, 0.08);
}

.message-user {
  margin-left: auto;
  max-width: 88%;
  background: var(--user-bg);
}

.message-assistant {
  margin-right: auto;
  max-width: 92%;
  background: var(--assistant-bg);
}

.message-role {
  margin: 0 0 8px;
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--accent);
}

.message-body {
  margin: 0;
  white-space: pre-wrap;
  word-break: break-word;
  font-family: "IBM Plex Mono", "Cascadia Code", monospace;
  font-size: 0.95rem;
  line-height: 1.6;
}

.composer {
  margin-top: 16px;
}

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

.challenge-grid .field:first-child,
.challenge-grid .field:nth-child(6),
.challenge-grid .field:nth-child(7) {
  grid-column: 1 / -1;
}

.challenge-result {
  margin-top: 16px;
  min-height: 88px;
  padding: 12px;
  border-radius: 20px;
  background: rgba(255, 255, 255, 0.62);
  border: 1px solid rgba(41, 55, 77, 0.08);
}

.label {
  display: block;
  margin-bottom: 10px;
  font-weight: 700;
}

.label.compact {
  margin-bottom: 0;
}

input,
select,
textarea {
  font: inherit;
}

input,
select {
  width: 100%;
  padding: 10px 12px;
  border: 1px solid rgba(41, 55, 77, 0.14);
  border-radius: 12px;
  color: inherit;
  background: rgba(255, 255, 255, 0.84);
}

textarea {
  width: 100%;
  padding: 14px 16px;
  border: 1px solid rgba(41, 55, 77, 0.14);
  border-radius: 18px;
  resize: vertical;
  color: inherit;
  background: rgba(255, 255, 255, 0.84);
}

input:focus,
select:focus,
textarea:focus,
button:focus {
  outline: 2px solid rgba(184, 92, 56, 0.28);
  outline-offset: 2px;
}

button {
  border: 0;
  border-radius: 999px;
  padding: 11px 18px;
  font: inherit;
  font-weight: 700;
  cursor: pointer;
  transition:
    transform 140ms ease,
    opacity 140ms ease;
}

button:hover:not(:disabled) {
  transform: translateY(-1px);
}

button:disabled {
  opacity: 0.55;
  cursor: not-allowed;
}

#new-chat-button,
#submit-button {
  color: #fff8f0;
  background: linear-gradient(135deg, var(--accent), var(--accent-dark));
}

.ghost {
  color: var(--accent-dark);
  background: rgba(184, 92, 56, 0.1);
}

#debate-submit-button {
  color: #fff8f0;
  background: linear-gradient(135deg, var(--accent), var(--accent-dark));
}

.status {
  min-height: 1.5em;
  color: var(--muted);
  font-size: 0.95rem;
}

.auth-tools {
  margin-top: 14px;
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 10px;
}

.auth-user {
  font-size: 0.9rem;
  color: var(--muted);
}

.auth-overlay {
  position: fixed;
  inset: 0;
  z-index: 40;
  display: grid;
  place-items: center;
  padding: 16px;
  background: rgba(17, 24, 39, 0.36);
  backdrop-filter: blur(4px);
}

.auth-overlay.hidden {
  display: none;
}

.auth-card {
  width: min(420px, 100%);
  padding: 22px;
  border-radius: 20px;
  background: rgba(250, 248, 243, 0.97);
  border: 1px solid var(--panel-border);
  box-shadow: var(--shadow);
}

.auth-card h2 {
  margin: 0;
  font-size: 1.4rem;
}

.auth-help {
  margin: 10px 0 16px;
  color: var(--muted);
  line-height: 1.6;
}

#login-button {
  color: #fff8f0;
  background: linear-gradient(135deg, var(--accent), var(--accent-dark));
}

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

.debate-form {
  margin-top: 16px;
}

.debate-workspace {
  margin-top: 18px;
  display: grid;
  gap: 16px;
  grid-template-columns: minmax(220px, 280px) minmax(0, 1fr);
  align-items: start;
}

.debate-history {
  padding: 12px;
  border-radius: 20px;
  background: rgba(255, 255, 255, 0.62);
  border: 1px solid rgba(41, 55, 77, 0.08);
}

.debate-list {
  margin-top: 10px;
  display: grid;
  gap: 10px;
}

.debate-item {
  display: grid;
  gap: 6px;
  padding: 10px 12px;
  border-radius: 16px;
  border: 1px solid rgba(41, 55, 77, 0.08);
  background: rgba(255, 255, 255, 0.5);
}

.debate-link {
  padding: 0;
  border-radius: 12px;
  background: transparent;
  color: inherit;
  text-align: left;
}

.debate-link.active {
  color: var(--accent-dark);
}

.debate-meta {
  font-size: 0.82rem;
  color: var(--muted);
}

.field {
  display: grid;
  gap: 8px;
}

.field:first-child {
  grid-column: 1 / -1;
}

.debate-result {
  min-height: 160px;
  padding: 12px;
  border-radius: 20px;
  background: rgba(255, 255, 255, 0.62);
  border: 1px solid rgba(41, 55, 77, 0.08);
}

.debate-summary {
  margin-bottom: 16px;
  padding: 14px 16px;
  border-radius: 18px;
  background: rgba(184, 92, 56, 0.08);
  border: 1px solid rgba(184, 92, 56, 0.12);
}

.debate-summary p {
  margin: 0 0 8px;
}

.debate-summary p:last-child {
  margin-bottom: 0;
}

@media (max-width: 920px) {
  .workspace {
    grid-template-columns: 1fr;
  }

  .debate-workspace {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 720px) {
  .shell {
    width: min(100%, calc(100% - 16px));
    padding-top: 16px;
  }

  .hero,
  .sidebar,
  .chat-panel,
  .debate-panel {
    padding: 18px;
  }

  .messages {
    min-height: 300px;
    max-height: 50vh;
  }

  .message-user,
  .message-assistant {
    max-width: 100%;
  }

  .sidebar-head,
  .toolbar,
  .actions,
  .provider-row {
    align-items: flex-start;
    flex-direction: column;
  }

  .chat-item {
    grid-template-columns: 1fr;
  }

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

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

  .chat-switch,
  .chat-delete,
  .chat-meta {
    grid-column: 1 / 2;
  }

  .field:first-child,
  .challenge-grid .field:nth-child(6),
  .challenge-grid .field:nth-child(7) {
    grid-column: 1 / 2;
  }
}


.nav-pill {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: 999px;
  padding: 11px 18px;
  font-weight: 700;
  text-decoration: none;
  transition: transform 140ms ease, opacity 140ms ease;
}

.nav-pill:hover {
  transform: translateY(-1px);
}

.nav-pill.primary {
  color: #fff8f0;
  background: linear-gradient(135deg, var(--accent), var(--accent-dark));
}

.nav-pill.ghost {
  color: var(--accent-dark);
  background: rgba(184, 92, 56, 0.1);
}

.api-links {
  margin-top: 10px;
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
  justify-content: flex-end;
}

.api-links a {
  color: var(--accent-dark);
  text-decoration: none;
  font-size: 0.88rem;
  padding: 6px 10px;
  border-radius: 999px;
  background: rgba(184, 92, 56, 0.1);
  border: 1px solid rgba(184, 92, 56, 0.2);
}

.api-links a:hover {
  text-decoration: underline;
}