/* Page-specific source rules for the research mockup.
   Shared editorial overrides remain in mockup.css. */
        * {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }

        body {
            background: #fff;
            color: #111;
            font-family: 'Inter', sans-serif;
            line-height: 1.5;
        }

        /* 统一页面头部（与 people 页面一致） */
        .page-header {
            text-align: left;
            padding: 1rem 0 1.5rem;
            margin-bottom: 1rem;
            border-bottom: 1px solid #eaeaea;
        }

        .page-title {
            font-size: 2rem;
            font-weight: 700;
            margin: 0 0 0.5rem;
            color: #1a1a1a;
        }

        .page-subtitle {
            font-size: 1rem;
            color: #4a4a4a;
            line-height: 1.5;
            margin-bottom: 0.5rem;
        }

        .chn-text {
            color: #4a4a4a;
            font-size: 0.9rem;
            border-left: 2px solid #ddd;
            padding-left: 1rem;
            margin-top: 0.5rem;
        }

        /* 统一区块标题 */
        .section-header {
            display: grid;
            grid-template-columns: 1fr auto;
            align-items: start;
            gap: 0.5rem 1rem;
            font-size: 1.25rem;
            font-weight: 600;
            letter-spacing: -0.2px;
            color: #111;
            margin: 2rem 0 1rem;
        }

        .section-header span {
            line-height: 1.4;
        }

        .section-header small {
            font-size: 0.8rem;
            font-weight: 400;
            color: #888;
            margin-left: 0.5rem;
            white-space: normal;
        }

        @media (max-width: 680px) {
            .page-title {
                font-size: 1.6rem;
            }

            .page-subtitle {
                font-size: 0.9rem;
            }

            .chn-text {
                font-size: 0.8rem;
            }

            .section-header {
                font-size: 1.1rem;
                margin: 1.5rem 0 0.75rem;
                gap: 0.3rem 0.8rem;
            }
        }

        .papers-category {
            margin-bottom: 2rem;
        }

        .research-tools {
            display: flex;
            align-items: center;
            gap: 0.75rem;
            margin: 1.5rem 0;
        }

        .research-tools label {
            font-size: 0.85rem;
            font-weight: 600;
        }

        .research-tools input {
            flex: 1;
            max-width: 420px;
            border: 1px solid #ccc;
            border-radius: 999px;
            padding: 0.65rem 0.9rem;
            font: inherit;
            font-size: 0.85rem;
        }

        @media (max-width: 680px) {
            .research-tools {
                align-items: stretch;
                flex-direction: column;
            }
            .research-tools input {
                max-width: none;
                width: 100%;
            }
        }

        .toggle-btn {
            background: transparent;
            border: 1px solid #ccc;
            width: 32px;
            height: 32px;
            cursor: pointer;
            transition: all 0.2s ease;
            display: inline-flex;
            align-items: center;
            justify-content: center;
            border-radius: 0px;
            padding: 0;
            flex-shrink: 0;
        }

        .toggle-btn:hover {
            border-color: #111;
            background: #f8f8f8;
        }

        .toggle-icon {
            display: inline-block;
            width: 16px;
            height: 16px;
            background-repeat: no-repeat;
            background-position: center;
            background-size: contain;
        }

        .icon-arrow-down {
            background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%23222222' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpolyline points='6 9 12 15 18 9'%3E%3C/polyline%3E%3C/svg%3E");
        }

        .icon-arrow-up {
            background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%23222222' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpolyline points='18 15 12 9 6 15'%3E%3C/polyline%3E%3C/svg%3E");
        }

        .paper-list-wrapper {
            display: block;
            overflow: hidden;
            transition: max-height 0.5s cubic-bezier(0.33, 1, 0.68, 1);
            max-height: var(--collapsed-height, 360px);
            position: relative;
        }

        .papers-category.expanded .paper-list-wrapper {
            max-height: var(--expanded-height, 5000px);
        }

        .paper-list {
            list-style: none;
            margin: 0;
            padding: 0;
        }

        .papers-category .paper-item {
            margin-bottom: 0.85rem;
            padding-bottom: 0.5rem;
            border-bottom: 1px solid #f2f2f2;
        }

        .paper-title {
            font-weight: 600;
            font-size: 0.9rem;
            margin-bottom: 0.15rem;
        }

        .paper-title a {
            color: #111;
            text-decoration: none;
            transition: color 0.2s, border-bottom 0.2s;
            border-bottom: 1px dotted transparent;
        }

        .paper-title a:hover {
            color: #000;
            border-bottom-color: #888;
        }

        .paper-authors,
        .paper-venue {
            font-size: 0.75rem;
            color: #555;
        }

        .paper-doi {
            font-size: 0.65rem;
            color: #888;
            margin-top: 0.2rem;
            font-family: 'Inter', sans-serif;
            letter-spacing: normal;
        }

        .paper-doi a {
            color: #888;
            text-decoration: none;
            border-bottom: 1px dotted #ccc;
            transition: color 0.2s, border-bottom-color 0.2s;
        }

        .paper-doi a:hover {
            color: #111;
            border-bottom-color: #111;
        }

        .footer {
            text-align: center;
            padding: 2rem;
            border-top: 1px solid #ececec;
            color: #5a5a5a;
            font-size: 0.8rem;
            margin-top: 1rem;
        }

        @media (max-width: 680px) {

            .paper-authors {
                font-size: 0.7rem;
                margin-top: 0.1rem;
            }

            .paper-venue {
                display: block;
                font-size: 0.68rem;
                line-height: 1.35;
            }

            .paper-doi {
                display: block;
                font-size: 0.62rem;
                overflow-wrap: anywhere;
            }

            .paper-title {
                font-size: 0.8rem;
            }

            .papers-category .paper-item {
                margin-bottom: 0.6rem;
                padding-bottom: 0.4rem;
            }
        }

        /* 底部收起按钮容器 - 预设 */
        .collapse-bottom-btn-container {
            margin-top: 1rem;
            display: none;
        }

        .papers-category.expanded .collapse-bottom-btn-container {
            display: block;
        }

        .collapse-bottom-btn {
            display: flex;
            align-items: center;
            justify-content: center;
            gap: 0.5rem;
            width: 100%;
            padding: 0.6rem;
            background: #f8f8f8;
            border: 1px solid #e0e0e0;
            cursor: pointer;
            font-size: 0.8rem;
            font-weight: 500;
            color: #333;
            transition: all 0.2s ease;
            font-family: 'Inter', sans-serif;
        }

        .collapse-bottom-btn:hover {
            background: #f0f0f0;
            border-color: #111;
            color: #000;
        }

        .collapse-icon {
            font-size: 0.9rem;
            transition: transform 0.2s;
        }

        .collapse-bottom-btn:hover .collapse-icon {
            transform: translateY(-2px);
        }

        @media (max-width: 680px) {
            .collapse-bottom-btn {
                padding: 0.5rem;
                font-size: 0.7rem;
            }
        }