.vocal-page,
        .vocal-page * {
            box-sizing: border-box;
        }

        .vocal-page {
            font-family: "PingFang SC", "Microsoft YaHei", -apple-system, BlinkMacSystemFont, sans-serif;
            background: linear-gradient(135deg, #e8e4ff 0%, #f0e6ff 30%, #f8f2ff 60%, #f0f6ff 100%);
            background-attachment: fixed;
            min-height: 100vh;
            padding: 60px 20px;
            overflow-x: hidden;
        }

        .vocal-container {
            width: 1200px;
            max-width: 100%;
            margin: 0 auto;
        }

        /* 标题区域 */
        .vocal-header {
            text-align: center;
            margin-bottom: 50px;
        }

        .vocal-header h1 {
            font-size: 42px;
            font-weight: 700;
            color: #1a1a2e;
            margin-bottom: 12px;
            letter-spacing: 4px;
        }

        .vocal-header p {
            font-size: 16px;
            color: #8888a0;
            letter-spacing: 1px;
        }

        /* 介绍卡片 */
        .vocal-intro-card {
            background: linear-gradient(135deg, #6c4ed6 0%, #8b6fd9 50%, #a88be5 100%);
            border-radius: 20px;
            padding: 40px 48px;
            margin-bottom: 50px;
            color: #fff;
            box-shadow: 0 16px 40px rgba(108, 78, 214, 0.28);
            position: relative;
            overflow: hidden;
        }

        .vocal-intro-card::before {
            content: '';
            position: absolute;
            top: -50%;
            right: -20%;
            width: 400px;
            height: 400px;
            background: radial-gradient(circle, rgba(255,255,255,0.1) 0%, transparent 60%);
            border-radius: 50%;
        }

        .vocal-intro-card p {
            font-size: 15.5px;
            line-height: 1.9;
            margin-bottom: 16px;
            position: relative;
            z-index: 1;
        }

        .vocal-intro-card p:last-child {
            margin-bottom: 0;
        }

        .vocal-intro-card strong {
            font-weight: 700;
            color: #70f5ff;
        }

        .vocal-highlight {
            color: #70f5ff;
            text-shadow: 0 0 8px rgba(255, 224, 102, 0.6);
        }

        /* ========== 阶段区域 ========== */
        .vocal-stage-section {
            display: flex;
            gap: 32px;
            align-items: center;
        }

        /* 左侧按钮组 */
        .vocal-stage-nav {
            display: flex;
            flex-direction: column;
            gap: 60px;
            flex-shrink: 0;
        }

        /* 按钮基础样式 —— 未选中：wxz.png 背景 */
        .vocal-stage-btn {
            display: block;
            padding: 20px 56px;
            border-radius: 40px;
            background: url('https://www.yezixueyuan.com/static/images2/wxz.png') no-repeat center / 100% 100%;
            border: none;
            color: #7c5ec8;
            font-size: 30px;
            font-weight: 500;
            letter-spacing: 3px;
            cursor: pointer;
            transition: all 0.25s ease;
            white-space: nowrap;
            outline: none;
        }

        .vocal-stage-btn:hover {
            opacity: 0.85;
        }

        /* 激活态 —— 选中：xzk.png 背景 */
        .vocal-stage-btn.vocal-active {
            background: url('https://www.yezixueyuan.com/static/images2/xzk.png') no-repeat center / 100% 100%;
            border: none;
            color: #fff;
        }

        /* 右侧图片卡片 —— 自动填满剩余空间 */
        .vocal-stage-detail {
            flex: 1;
            min-width: 0;
        }

        .vocal-stage-detail-content {
            display: none;
            animation: vocal-fadeIn 0.4s ease;
            border-radius: 20px;
            overflow: hidden;
        }

        .vocal-stage-detail-content.vocal-active {
            display: block;
        }

        .vocal-stage-detail-content img {
            width: 100%;
            height: auto;
            display: block;
        }

        @keyframes vocal-fadeIn {
            from {
                opacity: 0;
                transform: translateY(8px);
            }
            to {
                opacity: 1;
                transform: translateY(0);
            }
        }

        /* ===== 四大核心升级亮点 ===== */
        .vocal-upgrade-section {
            margin-top: 80px;
        }

        .vocal-upgrade-title {
            text-align: center;
            font-size: 42px;
            font-weight: 700;
            color: #fff;
            letter-spacing: 4px;
            background: linear-gradient(90deg, #6c4ed6, #a88be5);
            padding: 12px 0;
            border-radius: 40px;
            width: 430px;
            margin: 0 auto 50px;
            box-shadow: 0 8px 24px rgba(108, 78, 214, 0.25);
        }

        .vocal-upgrade-list {
            display: flex;
            flex-direction: column;
            gap: 28px;
        }

        .vocal-upgrade-card {
            border-radius: 18px;
            overflow: hidden;
            box-shadow: 0 6px 24px rgba(108, 78, 214, 0.12);
            background: #fff;
        }

        .vocal-upgrade-card img {
            width: 100%;
            height: auto;
            display: block;
        }

        /* ===== 响应式：平板 992-1199px ===== */
        @media (max-width: 1199px) {
            .vocal-page {
                padding: 40px 16px;
            }

            .vocal-header {
                margin-bottom: 40px;
            }

            .vocal-header h1 {
                font-size: 36px;
            }

            .vocal-intro-card {
                padding: 32px 36px;
                margin-bottom: 40px;
            }

            .vocal-stage-nav {
                gap: 48px;
            }

            .vocal-stage-btn {
                padding: 18px 48px;
                font-size: 26px;
                letter-spacing: 2px;
            }
        }

        /* ===== 响应式：平板小 768-991px ===== */
        @media (max-width: 991px) {
            .vocal-stage-section {
                gap: 24px;
            }

            .vocal-stage-nav {
                gap: 36px;
            }

            .vocal-stage-btn {
                padding: 16px 40px;
                font-size: 22px;
                letter-spacing: 2px;
            }
        }

        /* ===== 响应式：手机 ≤767px ===== */
        @media (max-width: 767px) {
            .vocal-page {
                padding: 30px 12px;
            }

            .vocal-header {
                margin-bottom: 32px;
            }

            .vocal-header h1 {
                font-size: 28px;
                letter-spacing: 2px;
            }

            .vocal-header p {
                font-size: 14px;
            }

            .vocal-intro-card {
                padding: 24px 20px;
                border-radius: 16px;
                margin-bottom: 32px;
            }

            .vocal-intro-card p {
                font-size: 14px;
                line-height: 1.8;
                margin-bottom: 12px;
            }

            .vocal-stage-section {
                flex-direction: column;
                gap: 20px;
                align-items: stretch;
            }

            .vocal-stage-nav {
                flex-direction: row;
                flex-wrap: wrap;
                gap: 12px;
            }

            .vocal-stage-btn {
                flex: 1 1 calc(50% - 6px);
                padding: 12px 20px;
                font-size: 16px;
                letter-spacing: 1px;
                text-align: center;
                border-radius: 28px;
            }

            .vocal-stage-detail-content {
                border-radius: 12px;
            }

            .vocal-upgrade-section {
                margin-top: 50px;
            }

            .vocal-upgrade-title {
                font-size: 22px;
                width: 260px;
                padding: 10px 0;
                letter-spacing: 2px;
                margin-bottom: 32px;
            }

            .vocal-upgrade-list {
                gap: 16px;
            }

            .vocal-upgrade-card {
                border-radius: 12px;
            }
        }