/* ==========================================================================
   1. 디자인 시스템 토큰 (Variables & Theme)
   ========================================================================== */
:root {
    /* Brand Colors */
    --primary-blue: #3498db;
    --primary-dark: #2c3e50;
    --success-green: #2ecc71;
    --secondary-gray: #95a5a6;
    --danger-red: #e74c3c;

    /* Default: Dark Mode */
    --bg-main: #0f172a;
    --bg-card: #1e293b;
    --bg-nav: #0f172a;
    --text-main: #f1f5f9;
    --text-muted: #94a3b8;
    --border-color: #334155;
    --bg-card-inner: #0f172a;

    --sidebar-bg: #1e293b;
    --sidebar-bg-darker: #0f172a;
    --sidebar-text: #f1f5f9;
    --parent-bg: #334155;
    --parent-text: #f1f5f9;
    --child-border: #334155;
    --child-active-bg: #38bdf822;
    --child-active-text: #38bdf8;

    --sidebar-width: 300px;
    --nav-height: 52px;
    --footer-height: 48px;
    --bg-attachment: rgba(255, 255, 255, 0.05);
}

/* Light Mode Overrides */
html.light-mode {
    --bg-main: #f4f7f9;
    --bg-card: #ffffff;
    --bg-nav: #ffffff;
    --text-main: #2c3e50;
    --text-muted: #6c757d;
    --border-color: #dee2e6;
    --bg-card-inner: #f8f9fa;

    --sidebar-bg: #ecf4ff;
    --sidebar-bg-darker: #dee9fc;
    --sidebar-text: #1e40af;
    --parent-bg: #d1e5ff;
    --parent-text: #1e40af;
    --child-border: #e2e8f0;
    --child-active-bg: #cce0ff;
    --child-active-text: #1e40af;
    --bg-attachment: #e0f2fe;
}

* {
    box-sizing: border-box;
}

body,
html {
    height: 100%;
    margin: 0;
    font-family: 'Pretendard', -apple-system, sans-serif;
    background-color: var(--bg-main);
    color: var(--text-main);
}