:root {
            --bg: #f4f6f8;
            --card: #ffffff;
            --primary: #2563eb;
            --text: #111827;
            --muted: #6b7280;
            --border: #e5e7eb;
        }

        [data-theme="dark"] {
            --bg: #0f172a;
            --card: #020617;
            --primary: #60a5fa;
            --text: #e5e7eb;
            --muted: #94a3b8;
            --border: #1e293b;
        }

        * {
            box-sizing: border-box;
        }

        body {
            margin: 0;
            padding: 40px;
            font-family: system-ui, -apple-system, BlinkMacSystemFont, sans-serif;
            background: var(--bg);
            color: var(--text);
        }

        .app {
            max-width: 720px;
            margin: auto;
            background: var(--card);
            border-radius: 12px;
            padding: 24px 28px 32px;
            box-shadow: 0 10px 25px rgba(0,0,0,0.08);
        }

        h1 {
            margin-top: 0;
            margin-bottom: 24px;
        }

        .form {
            display: grid;
            grid-template-columns: 1fr 140px 160px auto;
            gap: 8px;
            margin-bottom: 24px;
        }

        input, select, button {
            height: 40px;
            border-radius: 8px;
            border: 1px solid var(--border);
            padding: 0 12px;
            font-size: 14px;
        }

        input:focus, select:focus {
            outline: none;
            border-color: var(--primary);
        }

        button {
            background: var(--primary);
            color: white;
            cursor: pointer;
            border: none;
            padding: 0 16px;
        }

        button:hover {
            opacity: 0.9;
        }

        ul {
            list-style: none;
            padding: 0;
            margin: 0;
        }

        li {
            display: flex;
            align-items: center;
            justify-content: space-between;
            padding: 12px 14px;
            border-radius: 8px;
            border: 1px solid var(--border);
            margin-bottom: 8px;
        }

        .info {
            display: flex;
            flex-direction: column;
        }

        .title {
            font-weight: 600;
        }

        .meta {
            font-size: 12px;
            color: var(--muted);
        }

        .tag {
            display: inline-block;
            font-size: 11px;
            padding: 2px 8px;
            border-radius: 999px;
            background: #eef2ff;
            color: var(--primary);
            margin-left: 6px;
        }

        .done {
            opacity: 0.5;
            text-decoration: line-through;
        }

        .complete {
            background: #10b981;
        }

        .complete:hover {
            opacity: 0.9;
        }

        #theme-toggle {
            position: fixed;
            top: 16px;
            right: 16px;
            background: var(--card);
            color: var(--text);
            border: 1px solid var(--border);
            border-radius: 50%;
            width: 42px;
            height: 42px;
            cursor: pointer;
}