:root {
    /* Custom Midnight Mint Palette */
    --bg-main: #0a0e17;
    --bg-sidebar: #111827;
    --bg-panel: #1f2937;
    --text-main: #e2e8f0;
    --text-muted: #64748b;
    --accent: #10b981; /* Mint Green */
    --accent-hover: #059669;
    --wire-active: #34d399; /* Bright Neon Mint */
    --wire-idle: #334155;
    --border: #1e293b;
    --alert: #ef4444;
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
    /* Developer-focused typography */
    font-family: 'Fira Code', 'Consolas', 'Courier New', monospace;
}

body, html {
    height: 100%;
    overflow: hidden;
    background-color: var(--bg-main);
    color: var(--text-main);
    user-select: none;
}

#app-container { display: flex; height: 100vh; width: 100vw; }

/* Sidebar */
#sidebar {
    width: 280px;
    background-color: var(--bg-sidebar);
    border-right: 1px solid var(--border);
    display: flex;
    flex-direction: column;
    overflow-y: auto;
    box-shadow: 2px 0 15px rgba(0,0,0,0.3);
    z-index: 10;
}

#sidebar::-webkit-scrollbar { width: 4px; }
#sidebar::-webkit-scrollbar-track { background: transparent; }
#sidebar::-webkit-scrollbar-thumb { background: var(--border); }
#sidebar::-webkit-scrollbar-thumb:hover { background: var(--accent); }

#brand {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 24px 20px;
    background-color: #0b111d;
    border-bottom: 2px solid var(--border);
}

#brand h1 { font-size: 16px; font-weight: 700; color: #ffffff; letter-spacing: -0.5px; }

.sidebar-section { padding: 15px 20px; border-bottom: 1px solid var(--border); }
.sidebar-section h2 { font-size: 11px; text-transform: uppercase; color: var(--accent); margin-bottom: 12px; font-weight: 700; }

/* Buttons */
.file-group { display: flex; gap: 6px; }

.file-btn, .action-btn {
    flex: 1;
    background-color: var(--bg-panel);
    color: var(--text-main);
    border: 1px solid var(--border);
    padding: 8px;
    font-size: 11px;
    border-radius: 4px;
    cursor: pointer;
    transition: all 0.2s ease;
}

.file-btn:hover, .action-btn:hover { background-color: #374151; border-color: var(--accent); }
.alert-btn:hover { background-color: #451a1a; border-color: var(--alert); color: var(--alert); }
.action-btn { background-color: rgba(16, 185, 129, 0.1); border-color: var(--accent); color: var(--accent); }
.action-btn:hover { background-color: var(--accent); color: #fff; }

.tool-btn {
    width: 100%;
    background-color: transparent;
    color: var(--text-main);
    border: 1px solid transparent;
    padding: 10px 12px;
    margin-bottom: 4px;
    border-radius: 4px;
    cursor: pointer;
    text-align: left;
    font-size: 12px;
    transition: all 0.15s ease;
    display: flex;
    align-items: center;
}

.tool-btn .icon { margin-right: 10px; color: var(--text-muted); font-size: 14px; }
.tool-btn:hover { background-color: var(--bg-panel); }
.tool-btn.active { background-color: rgba(16, 185, 129, 0.15); border: 1px solid var(--accent); color: #fff; }
.tool-btn.active .icon { color: var(--accent); }

/* Workspace & Canvas */
#workspace { flex-grow: 1; position: relative; background-color: var(--bg-main); }
canvas { display: block; width: 100%; height: 100%; cursor: crosshair; }

/* Tutorial Modal */
#tutorial-overlay {
    position: absolute;
    bottom: 40px;
    left: 50%;
    transform: translateX(-50%);
    background: rgba(17, 24, 39, 0.95);
    border: 1px solid var(--accent);
    border-radius: 8px;
    padding: 20px;
    width: 380px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.5), 0 0 15px rgba(16, 185, 129, 0.2);
    backdrop-filter: blur(5px);
    z-index: 100;
    transition: opacity 0.3s ease;
}

#tutorial-overlay.hidden, #test-overlay.hidden { opacity: 0; pointer-events: none; }
#tut-title, #test-title { font-size: 14px; color: var(--accent); margin-bottom: 10px; }
#tut-text { font-size: 12px; line-height: 1.5; color: #cbd5e1; margin-bottom: 20px; min-height: 54px; }

.tut-controls { display: flex; justify-content: space-between; align-items: center; }
#tut-progress { font-size: 11px; color: var(--text-muted); }
.tut-btn { padding: 6px 14px; font-size: 11px; border-radius: 4px; cursor: pointer; border: none; font-weight: bold; }
.tut-btn.primary { background: var(--accent); color: #000; }
.tut-btn.primary:hover { background: var(--wire-active); }
.tut-btn.secondary { background: transparent; color: var(--text-muted); }
.tut-btn.secondary:hover { color: #fff; }

/* Testbench UI */
.highlight-section {
    background-color: rgba(16, 185, 129, 0.05);
    border-bottom: 1px solid rgba(16, 185, 129, 0.2);
}

.dropdown {
    width: 100%;
    background-color: var(--bg-main);
    color: var(--text-main);
    border: 1px solid var(--border);
    padding: 8px;
    font-size: 11px;
    border-radius: 4px;
    outline: none;
    cursor: pointer;
}

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

#test-overlay {
    position: absolute;
    top: 50px;
    left: 50%;
    transform: translateX(-50%);
    background: rgba(17, 24, 39, 0.98);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 20px;
    z-index: 100;
    transition: opacity 0.3s ease;
}

.test-card {
    width: 450px;
    border-color: var(--text-muted);
}

.test-card.success { border-color: var(--accent); box-shadow: 0 0 20px rgba(16, 185, 129, 0.3); }
.test-card.fail { border-color: var(--alert); box-shadow: 0 0 20px rgba(239, 68, 68, 0.3); }

.terminal-text {
    font-family: 'Fira Code', monospace;
    font-size: 11px;
    color: #a1a1aa;
    background: #000;
    padding: 12px;
    border-radius: 4px;
    min-height: 100px;
    max-height: 250px;
    overflow-y: auto;
    white-space: pre-wrap;
    line-height: 1.6;
}

.term-pass { color: var(--accent); font-weight: bold; }
.term-fail { color: var(--alert); font-weight: bold; }
.term-warn { color: #fbbf24; }