@import url('https://fonts.googleapis.com/css2?family=IBM+Plex+Mono:wght@400;600&family=Syne:wght@400;700;800&display=swap');

:root {
  --bg:        #0a0a0f;
  --surface:   #111118;
  --border:    #2a2a3a;
  --accent:    #e8ff47;
  --accent2:   #7b61ff;
  --text:      #e8e8f0;
  --muted:     #666680;
  --green:     #3ddc84;
  --red:       #ff5252;
  --radius:    6px;
  --mono:      'IBM Plex Mono', monospace;
  --sans:      'Syne', sans-serif;
}

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

html { font-size: 15px; }

body {
  background: var(--bg);
  color: var(--text);
  font-family: var(--sans);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* ── Header ── */
header {
  padding: 1.5rem 2rem;
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: baseline;
  gap: 1.5rem;
  flex-wrap: wrap;
}

.logo {
  font-size: 1.4rem;
  font-weight: 800;
  letter-spacing: -0.02em;
  color: var(--text);
  text-decoration: none;
}

.logo span {
  color: var(--accent);
}

.subtitle {
  font-family: var(--mono);
  font-size: 0.75rem;
  color: var(--muted);
  letter-spacing: 0.05em;
}

/* ── Main ── */
main {
  flex: 1;
  max-width: 1200px;
  width: 100%;
  margin: 0 auto;
  padding: 2rem;
}

.intro {
  margin-bottom: 2rem;
  font-size: 0.9rem;
  color: var(--muted);
  font-family: var(--mono);
  border-left: 3px solid var(--accent2);
  padding-left: 1rem;
}

/* ── Task Grid ── */
.task-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 1px;
  background: var(--border);
  border: 1px solid var(--border);
}

.task-card {
  background: var(--surface);
  padding: 1.5rem;
  cursor: pointer;
  transition: background 0.15s;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  text-decoration: none;
  color: inherit;
}

.task-card:hover {
  background: #16161f;
}

.task-card:hover .task-arrow {
  transform: translateX(4px);
}

.task-num {
  font-family: var(--mono);
  font-size: 0.7rem;
  color: var(--accent);
  letter-spacing: 0.1em;
}

.task-name {
  font-size: 1rem;
  font-weight: 700;
  line-height: 1.3;
}

.task-desc {
  font-family: var(--mono);
  font-size: 0.75rem;
  color: var(--muted);
  line-height: 1.5;
  flex: 1;
}

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

.task-tag {
  font-family: var(--mono);
  font-size: 0.65rem;
  padding: 0.2rem 0.5rem;
  border: 1px solid var(--border);
  color: var(--muted);
  border-radius: 2px;
}

.task-arrow {
  color: var(--accent);
  font-size: 1.1rem;
  transition: transform 0.15s;
}

.loading {
  grid-column: 1/-1;
  padding: 3rem;
  text-align: center;
  font-family: var(--mono);
  color: var(--muted);
}

/* ── Task Page ── */
.task-description {
  font-family: var(--mono);
  font-size: 0.85rem;
  color: var(--muted);
  background: var(--surface);
  border: 1px solid var(--border);
  padding: 1rem 1.25rem;
  margin-bottom: 1.5rem;
  border-left: 3px solid var(--accent2);
  line-height: 1.6;
}

.run-bar {
  display: flex;
  align-items: center;
  gap: 1rem;
  margin-bottom: 1.5rem;
}

.btn-run {
  font-family: var(--mono);
  font-size: 0.85rem;
  font-weight: 600;
  letter-spacing: 0.05em;
  background: var(--accent);
  color: #000;
  border: none;
  padding: 0.6rem 1.4rem;
  cursor: pointer;
  border-radius: var(--radius);
  transition: opacity 0.15s, transform 0.1s;
}

.btn-run:hover { opacity: 0.85; }
.btn-run:active { transform: scale(0.97); }
.btn-run:disabled { opacity: 0.4; cursor: not-allowed; }

.run-status {
  font-family: var(--mono);
  font-size: 0.75rem;
  color: var(--muted);
}

/* ── Arena ── */
.arena {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  gap: 0;
  border: 1px solid var(--border);
  background: var(--border);
  min-height: 400px;
}

.vs-divider {
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--bg);
  font-family: var(--mono);
  font-size: 0.7rem;
  font-weight: 600;
  color: var(--muted);
  writing-mode: vertical-rl;
  padding: 1rem 0.5rem;
  letter-spacing: 0.2em;
}

.agent-panel {
  background: var(--surface);
  display: flex;
  flex-direction: column;
}

.agent-header {
  padding: 0.75rem 1.25rem;
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  background: var(--bg);
}

.agent-label {
  font-weight: 700;
  font-size: 0.95rem;
  color: var(--accent);
}

.agent-meta {
  font-family: var(--mono);
  font-size: 0.65rem;
  color: var(--muted);
}

/* ── Trace ── */
.trace {
  flex: 1;
  padding: 1rem 1.25rem;
  font-family: var(--mono);
  font-size: 0.78rem;
  line-height: 1.6;
  overflow-y: auto;
  max-height: 500px;
}

.trace-step {
  margin-bottom: 1rem;
  animation: fadeIn 0.3s ease forwards;
  opacity: 0;
}

@keyframes fadeIn {
  to { opacity: 1; }
}

.step-header {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  margin-bottom: 0.3rem;
}

.step-num {
  background: var(--border);
  color: var(--muted);
  font-size: 0.65rem;
  padding: 0.1rem 0.4rem;
  border-radius: 2px;
}

.step-type {
  font-size: 0.7rem;
  font-weight: 600;
  letter-spacing: 0.08em;
}

.step-type.think   { color: var(--accent2); }
.step-type.action  { color: var(--accent); }
.step-type.result  { color: var(--green); }
.step-type.error   { color: var(--red); }

.step-content {
  background: var(--bg);
  border: 1px solid var(--border);
  padding: 0.5rem 0.75rem;
  border-radius: var(--radius);
  white-space: pre-wrap;
  word-break: break-word;
  color: var(--text);
}

.step-content.think-content {
  border-left: 2px solid var(--accent2);
  color: var(--muted);
  font-style: italic;
}

.final-answer {
  border-top: 1px solid var(--border);
  padding: 1rem 1.25rem;
  font-family: var(--mono);
  font-size: 0.8rem;
  line-height: 1.6;
  background: var(--bg);
}

.final-answer-label {
  font-size: 0.65rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  color: var(--green);
  margin-bottom: 0.5rem;
}

.final-answer-text {
  white-space: pre-wrap;
  color: var(--text);
}

/* ── Vote buttons ── */
.btn-vote {
  font-family: var(--mono);
  font-size: 0.8rem;
  font-weight: 600;
  background: transparent;
  border: 1px solid var(--border);
  color: var(--muted);
  padding: 0.75rem;
  cursor: pointer;
  transition: all 0.15s;
  letter-spacing: 0.05em;
}

.btn-vote:hover {
  background: var(--accent);
  color: #000;
  border-color: var(--accent);
}

.btn-vote.winner {
  background: var(--green);
  color: #000;
  border-color: var(--green);
}

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

/* ── Vote result ── */
.vote-result {
  margin-top: 1.5rem;
  padding: 1rem 1.5rem;
  border: 1px solid var(--border);
  font-family: var(--mono);
  font-size: 0.85rem;
  background: var(--surface);
}

.vote-result .reveal-label {
  font-size: 0.65rem;
  letter-spacing: 0.1em;
  color: var(--muted);
  margin-bottom: 0.5rem;
}

.vote-result .model-reveal {
  font-size: 1rem;
  font-weight: 700;
}

.model-a { color: var(--accent); }
.model-b { color: var(--accent2); }

/* ── Spinner ── */
.spinner {
  display: inline-block;
  width: 10px;
  height: 10px;
  border: 2px solid var(--border);
  border-top-color: var(--accent);
  border-radius: 50%;
  animation: spin 0.6s linear infinite;
  margin-right: 0.4rem;
  vertical-align: middle;
}

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

/* ── Footer ── */
footer {
  padding: 1rem 2rem;
  border-top: 1px solid var(--border);
  font-family: var(--mono);
  font-size: 0.65rem;
  color: var(--muted);
  letter-spacing: 0.05em;
}

@media (max-width: 700px) {
  .arena {
    grid-template-columns: 1fr;
    grid-template-rows: auto auto auto;
  }
  .vs-divider {
    writing-mode: horizontal-tb;
    padding: 0.5rem;
  }
}