/* ARIANE  Mise en page principale, header, horloge */

        /* DASHBOARD SCREEN */
        #dashboard-screen {
            display: none;
        }

        #dashboard-screen.visible {
            display: block;
        }

        header {
            text-align: center;
            color: white;
            margin-bottom: 40px;
        }

        header h1 {
            font-size: 2.5em;
            margin-bottom: 10px;
            text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.3);
        }

        header p {
            font-size: 1.1em;
            opacity: 0.95;
        }

        .header-top {
            display: flex;
            justify-content: space-between;
            align-items: center;
            margin-bottom: 20px;
        }

        .digital-clock {
            color: white;
            font-size: 1.2em;
            font-weight: 600;
            font-family: 'Courier New', monospace;
            opacity: 0.9;
            letter-spacing: 2px;
            text-shadow: 1px 1px 2px rgba(0, 0, 0, 0.3);
        }

        .seDeconnecter-btn {
            background: rgba(255, 255, 255, 0.2);
            color: white;
            border: 1px solid rgba(255, 255, 255, 0.5);
            padding: 8px 16px;
            border-radius: 6px;
            cursor: pointer;
            font-size: 0.9em;
            transition: all 0.3s;
            text-decoration: none;
        }

        .seDeconnecter-btn:hover {
            background: rgba(255, 255, 255, 0.3);
            border-color: white;
        }

        .tabs {
            display: flex;
            gap: 8px;
            margin-bottom: 30px;
            background: white;
            padding: 12px;
            border-radius: 12px;
            box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
            flex-wrap: nowrap;
            overflow-x: auto;
        }

        .tab-button {
            padding: 10px 16px;
            border: none;
            background: #f0f0f0;
            color: #333;
            border-radius: 8px;
            cursor: pointer;
            font-size: 0.9em;
            font-weight: 500;
            transition: all 0.3s;
            white-space: nowrap;
            flex-shrink: 0;
        }

        .tab-button.active {
            background: #667eea;
            color: white;
            box-shadow: 0 2px 8px rgba(102, 126, 234, 0.3);
        }

        .tab-button:hover {
            transform: translateY(-2px);
            box-shadow: 0 2px 8px rgba(0, 0, 0, 0.15);
        }

        .range-btn {
            padding: 10px 18px;
            border: 2px solid #667eea;
            background: white;
            color: #667eea;
            border-radius: 8px;
            cursor: pointer;
            font-size: 0.9em;
            font-weight: 500;
            transition: all 0.3s;
        }

        .range-btn.active {
            background: #667eea;
            color: white;
            box-shadow: 0 2px 8px rgba(102, 126, 234, 0.3);
        }

        .range-btn:hover {
            transform: translateY(-2px);
            box-shadow: 0 2px 8px rgba(102, 126, 234, 0.2);
        }