:root {
    --bg-primary: #0a0e1a;
    --bg-secondary: #111827;
    --bg-card: #1a2236;
    --bg-card-hover: #1f2a42;
    --accent: #4f8ff7;
    --accent-glow: rgba(79, 143, 247, 0.3);
    --accent-green: #10b981;
    --accent-orange: #f59e0b;
    --accent-red: #ef4444;
    --accent-purple: #8b5cf6;
    --text-primary: #f1f5f9;
    --text-secondary: #94a3b8;
    --text-muted: #64748b;
    --border: #1e293b;
    --radius: 12px;
    --font: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
}

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

body {
    font-family: var(--font);
    background: var(--bg-primary);
    color: var(--text-primary);
    min-height: 100vh;
    line-height: 1.6;
}

.header {
    text-align: center;
    padding: 3rem 2rem 2rem;
    background: linear-gradient(180deg, #0f1629 0%, var(--bg-primary) 100%);
    border-bottom: 1px solid var(--border);
}

.header-brand {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 1rem;
    margin-bottom: 0.5rem;
}

.logo-mark {
    font-size: 2rem;
    background: linear-gradient(135deg, var(--accent), var(--accent-purple));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.header h1 {
    font-size: 2rem;
    font-weight: 700;
    background: linear-gradient(135deg, var(--text-primary), var(--accent));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.badge {
    background: var(--accent);
    color: white;
    font-size: 0.7rem;
    padding: 0.25rem 0.75rem;
    border-radius: 20px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.header-subtitle {
    color: var(--text-secondary);
    font-size: 1.1rem;
    margin-top: 0.5rem;
}

.tab-nav {
    display: flex;
    gap: 0.25rem;
    padding: 1rem 2rem;
    overflow-x: auto;
    background: var(--bg-secondary);
    border-bottom: 1px solid var(--border);
    position: sticky;
    top: 0;
    z-index: 100;
}

.tab-btn {
    background: transparent;
    border: 1px solid transparent;
    color: var(--text-secondary);
    padding: 0.6rem 1.2rem;
    border-radius: 8px;
    cursor: pointer;
    font-size: 0.85rem;
    font-weight: 500;
    white-space: nowrap;
    transition: all 0.2s ease;
}

.tab-btn:hover {
    color: var(--text-primary);
    background: var(--bg-card);
}

.tab-btn.active {
    color: var(--accent);
    background: var(--bg-card);
    border-color: var(--accent);
    box-shadow: 0 0 12px var(--accent-glow);
}

.content {
    max-width: 1200px;
    margin: 0 auto;
    padding: 2rem;
    min-height: 70vh;
}

.card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 2rem;
    margin-bottom: 1.5rem;
    transition: all 0.2s ease;
}

.card:hover {
    background: var(--bg-card-hover);
    border-color: var(--accent);
    box-shadow: 0 4px 20px rgba(0,0,0,0.3);
}

.card h3 {
    font-size: 1.2rem;
    margin-bottom: 0.75rem;
    color: var(--text-primary);
}

.card p {
    color: var(--text-secondary);
    font-size: 0.95rem;
}

.grid-2 {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 1.5rem;
}

.grid-3 {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 1.5rem;
}

.section-title {
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
    color: var(--text-primary);
}

.section-subtitle {
    color: var(--text-secondary);
    margin-bottom: 2rem;
    font-size: 1rem;
}

/* Stats */
.stats-row {
    display: flex;
    gap: 2rem;
    margin-bottom: 2rem;
    flex-wrap: wrap;
}

.stat {
    text-align: center;
    flex: 1;
    min-width: 120px;
}

.stat-value {
    font-size: 2.5rem;
    font-weight: 800;
    color: var(--accent);
}

.stat-label {
    font-size: 0.8rem;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    margin-top: 0.25rem;
}

/* Demo panel */
.demo-panel {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    overflow: hidden;
}

.demo-header {
    padding: 1.5rem 2rem;
    border-bottom: 1px solid var(--border);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.demo-body {
    padding: 2rem;
    min-height: 400px;
}

.btn {
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: 8px;
    font-size: 0.9rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s ease;
}

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

.btn-primary:hover {
    background: #3a7ae0;
    box-shadow: 0 4px 16px var(--accent-glow);
}

.btn-danger {
    background: var(--accent-red);
    color: white;
}

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

/* Investigation journal */
.journal {
    font-family: 'JetBrains Mono', 'Fira Code', monospace;
    font-size: 0.85rem;
    line-height: 1.8;
}

.journal-entry {
    padding: 0.75rem 1rem;
    border-left: 3px solid var(--border);
    margin-bottom: 0.75rem;
    animation: fadeIn 0.4s ease;
}

.journal-entry.step-thinking { border-left-color: var(--accent-purple); }
.journal-entry.step-action { border-left-color: var(--accent); }
.journal-entry.step-finding { border-left-color: var(--accent-orange); }
.journal-entry.step-rca { border-left-color: var(--accent-green); }
.journal-entry.step-error { border-left-color: var(--accent-red); }

.journal-entry .timestamp {
    color: var(--text-muted);
    font-size: 0.75rem;
}

.journal-entry .label {
    font-weight: 600;
    text-transform: uppercase;
    font-size: 0.7rem;
    letter-spacing: 0.5px;
    margin: 0 0.5rem;
}

.label-thinking { color: var(--accent-purple); }
.label-action { color: var(--accent); }
.label-finding { color: var(--accent-orange); }
.label-rca { color: var(--accent-green); }

/* Scenario selector */
.scenario-list {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
    margin-bottom: 1.5rem;
}

.scenario-item {
    padding: 1rem 1.5rem;
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.2s ease;
}

.scenario-item:hover, .scenario-item.selected {
    border-color: var(--accent);
    background: var(--bg-card-hover);
}

.scenario-item h4 { margin-bottom: 0.25rem; }
.scenario-item p { font-size: 0.85rem; color: var(--text-muted); }

/* Architecture diagram */
.arch-diagram {
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 2rem;
    font-family: monospace;
    font-size: 0.8rem;
    line-height: 1.6;
    color: var(--text-secondary);
    overflow-x: auto;
    white-space: pre;
}

/* Tag/pill styles */
.tag {
    display: inline-block;
    padding: 0.2rem 0.6rem;
    border-radius: 4px;
    font-size: 0.75rem;
    font-weight: 600;
    margin-right: 0.5rem;
    margin-bottom: 0.25rem;
}

.tag-blue { background: rgba(79,143,247,0.15); color: var(--accent); }
.tag-green { background: rgba(16,185,129,0.15); color: var(--accent-green); }
.tag-orange { background: rgba(245,158,11,0.15); color: var(--accent-orange); }
.tag-purple { background: rgba(139,92,246,0.15); color: var(--accent-purple); }
.tag-red { background: rgba(239,68,68,0.15); color: var(--accent-red); }

/* Flow diagram */
.flow {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 1.5rem;
    overflow-x: auto;
    flex-wrap: wrap;
}

.flow-node {
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 1rem 1.5rem;
    text-align: center;
    min-width: 140px;
}

.flow-node.active {
    border-color: var(--accent);
    box-shadow: 0 0 12px var(--accent-glow);
}

.flow-arrow {
    color: var(--text-muted);
    font-size: 1.5rem;
}

/* Status indicator */
.status-dot {
    display: inline-block;
    width: 8px;
    height: 8px;
    border-radius: 50%;
    margin-right: 0.5rem;
}

.status-dot.active { background: var(--accent-green); box-shadow: 0 0 6px var(--accent-green); }
.status-dot.pending { background: var(--accent-orange); }
.status-dot.error { background: var(--accent-red); }

/* Animation */
@keyframes fadeIn {
    from { opacity: 0; transform: translateY(8px); }
    to { opacity: 1; transform: translateY(0); }
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.5; }
}

.loading { animation: pulse 1.5s infinite; }

/* Feature list */
.feature-list {
    list-style: none;
    padding: 0;
}

.feature-list li {
    padding: 0.75rem 0;
    border-bottom: 1px solid var(--border);
    display: flex;
    align-items: flex-start;
    gap: 0.75rem;
}

.feature-list li:last-child { border-bottom: none; }

.feature-icon {
    width: 32px;
    height: 32px;
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1rem;
    flex-shrink: 0;
}

.icon-blue { background: rgba(79,143,247,0.15); }
.icon-green { background: rgba(16,185,129,0.15); }
.icon-orange { background: rgba(245,158,11,0.15); }
.icon-purple { background: rgba(139,92,246,0.15); }

/* Code block */
.code-block {
    background: #0d1117;
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 1.5rem;
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.8rem;
    line-height: 1.7;
    overflow-x: auto;
    color: #c9d1d9;
}

.code-block .keyword { color: #ff7b72; }
.code-block .string { color: #a5d6ff; }
.code-block .comment { color: #8b949e; }
.code-block .func { color: #d2a8ff; }

/* Footer */
.footer {
    text-align: center;
    padding: 2rem;
    color: var(--text-muted);
    font-size: 0.85rem;
    border-top: 1px solid var(--border);
}

/* Responsive */
@media (max-width: 768px) {
    .content { padding: 1rem; }
    .tab-nav { padding: 0.75rem 1rem; }
    .stats-row { gap: 1rem; }
    .stat-value { font-size: 1.8rem; }
    .grid-2, .grid-3 { grid-template-columns: 1fr; }
}