/* ---------------------------------------------------------
           1. Base & Variables
           --------------------------------------------------------- */
        :root {
            /* 配色：ログイン・登録画面（淡いブルーグレー・グレージュ） */
            --bg-auth: #f0f2f5;
            --bg-auth-gradient: linear-gradient(135deg, #f0f2f5 0%, #e6e9ef 100%);
            
            /* 配色：作業画面（低刺激なブルーグレー） */
            --bg-main: #edf1f4;
            --sidebar-bg: #2c3e50;
            --sidebar-text: #ecf0f1;
            
            /* 文字・アクセントカラー */
            --text-main: #333c44;
            --text-sub: #606f7b;
            --accent-navy: #1a3a5f;
            --accent-blue: #3498db;
            --success-green: #27ae60;
            --danger-red: #e74c3c;
            --border-color: #d1d9e0;
            --card-bg: #ffffff;
            
            /* 共通設定 */
            --shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
            --radius: 8px;
            --transition: all 0.3s ease;
        }

        * {
            box-sizing: border-box;
            margin: 0;
            padding: 0;
            font-family: "Helvetica Neue", Arial, "Hiragino Kaku Gothic ProN", "Hiragino Sans", Meiryo, sans-serif;
        }

        body, html {
            height: 100%;
            width: 100%;
            color: var(--text-main);
            overflow: hidden; /* 各画面内でスクロール管理 */
        }

        .hidden { display: none !important; }

        /* ---------------------------------------------------------
           2. Splash (Logo) Screen
           --------------------------------------------------------- */
        #screen-splash {
            height: 100vh;
            display: flex;
            flex-direction: column;
            justify-content: center;
            align-items: center;
            background: var(--bg-auth-gradient);
            z-index: 1000;
        }

        .logo-container {
            text-align: center;
            animation: fadeIn 1.2s ease;
        }

        .logo-mark {
            width: 100px;
            height: 100px;
            background: var(--accent-navy);
            border-radius: 20%;
            margin: 0 auto 20px;
            display: flex;
            justify-content: center;
            align-items: center;
            box-shadow: var(--shadow);
            position: relative;
        }

        .logo-mark::after {
            content: '✓';
            color: white;
            font-size: 60px;
            font-weight: bold;
        }

        .app-name {
            font-size: 2.5rem;
            color: var(--accent-navy);
            font-weight: 700;
            letter-spacing: 2px;
            margin-bottom: 8px;
        }

        .app-subtitle {
            font-size: 1rem;
            color: var(--text-sub);
            font-weight: 400;
        }

        /* ---------------------------------------------------------
           3. Auth Screens (Login & Register)
           --------------------------------------------------------- */
        .auth-wrapper {
            height: 100vh;
            background: var(--bg-auth-gradient);
            display: flex;
            justify-content: center;
            align-items: center;
        }

        .auth-card {
            background: var(--card-bg);
            width: 400px;
            padding: 40px;
            border-radius: var(--radius);
            box-shadow: var(--shadow);
        }

        .auth-card h2 {
            margin-bottom: 24px;
            text-align: center;
            color: var(--accent-navy);
        }

        .form-group {
            margin-bottom: 20px;
        }

        .form-group label {
            display: block;
            margin-bottom: 8px;
            font-size: 0.9rem;
            font-weight: 600;
        }

        .form-control {
            width: 100%;
            padding: 12px;
            border: 1px solid var(--border-color);
            border-radius: 4px;
            font-size: 1rem;
            transition: var(--transition);
        }

        .form-control:focus {
            outline: none;
            border-color: var(--accent-blue);
            box-shadow: 0 0 0 3px rgba(52, 152, 219, 0.2);
        }

        .btn {
            cursor: pointer;
            padding: 12px 20px;
            border: none;
            border-radius: 4px;
            font-size: 1rem;
            font-weight: 600;
            transition: var(--transition);
            width: 100%;
            text-align: center;
        }

        .btn-primary { background: var(--accent-navy); color: white; margin-bottom: 12px; }
        .btn-primary:hover { opacity: 0.9; }
        .btn-link { background: transparent; color: var(--text-sub); text-decoration: underline; font-size: 0.85rem; }

        .error-msg {
            color: var(--danger-red);
            font-size: 0.85rem;
            margin-bottom: 15px;
            min-height: 1.2em;
        }

        /* ---------------------------------------------------------
           4. Main Dashboard Screen
           --------------------------------------------------------- */
        #screen-main {
            height: 100vh;
            display: grid;
            grid-template-columns: 260px 1fr;
            background: var(--bg-main);
        }

        /* Sidebar */
        aside {
            background: var(--sidebar-bg);
            color: var(--sidebar-text);
            display: flex;
            flex-direction: column;
            padding: 20px 0;
        }

        .aside-header {
            padding: 0 20px 30px;
            border-bottom: 1px solid rgba(255,255,255,0.1);
            margin-bottom: 20px;
        }

        .aside-header h1 {
            font-size: 1.2rem;
            display: flex;
            align-items: center;
        }

        nav ul { list-style: none; }
        nav li {
            padding: 12px 25px;
            cursor: pointer;
            transition: var(--transition);
            font-size: 0.95rem;
            display: flex;
            align-items: center;
        }
        nav li:hover { background: rgba(255,255,255,0.1); }
        nav li.active { background: var(--accent-blue); }

        .user-info {
            margin-top: auto;
            padding: 20px;
            border-top: 1px solid rgba(255,255,255,0.1);
            font-size: 0.85rem;
        }

        /* Main Content Area */
        main {
            padding: 30px;
            overflow-y: auto;
        }

        .content-header {
            display: flex;
            justify-content: space-between;
            align-items: center;
            margin-bottom: 30px;
        }

        .card {
            background: var(--card-bg);
            border-radius: var(--radius);
            padding: 24px;
            box-shadow: 0 2px 6px rgba(0,0,0,0.04);
            margin-bottom: 30px;
        }

        /* Controls: Search & Filter */
        .controls {
            display: flex;
            gap: 15px;
            margin-bottom: 20px;
            flex-wrap: wrap;
        }

        .search-input { flex: 1; min-width: 250px; }
        .filter-select { width: 180px; }

        /* Table */
        table {
            width: 100%;
            border-collapse: collapse;
            font-size: 0.9rem;
        }

        th, td {
            text-align: left;
            padding: 14px;
            border-bottom: 1px solid var(--border-color);
        }

        th { background: #f8f9fa; font-weight: 600; color: var(--text-sub); }

        .status-badge {
            padding: 4px 10px;
            border-radius: 20px;
            font-size: 0.8rem;
            font-weight: 600;
        }

        .status-pending { background: #fff3cd; color: #856404; }
        .status-approved { background: #d4edda; color: #155724; }
        .status-rejected { background: #f8d7da; color: #721c24; }

        .action-btns { display: flex; gap: 8px; }
        .btn-sm {
            padding: 6px 12px;
            font-size: 0.8rem;
            border-radius: 4px;
            border: 1px solid var(--border-color);
            background: #fff;
            cursor: pointer;
        }
        .btn-sm:hover { background: #f0f0f0; }
        .btn-approve { color: var(--success-green); border-color: var(--success-green); }
        .btn-reject { color: var(--danger-red); border-color: var(--danger-red); }

        /* Form */
        .apply-form {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 20px;
        }
        .apply-form .full { grid-column: span 2; }
        .apply-form textarea { height: 100px; resize: none; }

        /* ---------------------------------------------------------
           5. Modal
           --------------------------------------------------------- */
        .modal-overlay {
            position: fixed;
            top: 0; left: 0;
            width: 100%; height: 100%;
            background: rgba(0,0,0,0.5);
            display: flex;
            justify-content: center;
            align-items: center;
            z-index: 2000;
        }

        .modal-content {
            background: white;
            width: 600px;
            max-width: 90%;
            border-radius: var(--radius);
            padding: 30px;
            max-height: 85vh;
            overflow-y: auto;
            position: relative;
        }

        .modal-close {
            position: absolute;
            top: 15px; right: 15px;
            font-size: 24px;
            cursor: pointer;
            color: var(--text-sub);
        }

        .detail-grid {
            display: grid;
            grid-template-columns: 140px 1fr;
            gap: 15px;
            margin-top: 20px;
        }

        .detail-label { font-weight: 600; color: var(--text-sub); }

        @keyframes fadeIn {
            from { opacity: 0; transform: translateY(10px); }
            to { opacity: 1; transform: translateY(0); }
        }