.usecasedoc-page .usecasedoc-workspace {
    grid-template-columns: 140px 640px minmax(0, 1fr) 220px;
}

.usecasedoc-page .structure-input-column,
.usecasedoc-page .structure-preview-column,
.usecasedoc-page .structure-settings-column {
    min-height: 0;
}

.usecasedoc-input-panel {
    height: 100%;
}

.usecasedoc-input-panel .panel-body,
.usecasedoc-settings-panel .modern-params-body {
    padding: 12px;
}

.usecasedoc-input-panel .panel-body {
    flex: 1;
    min-height: 0;
    height: calc(100vh - 118px);
    overflow-y: auto;
    overflow-x: hidden;
    padding-right: 8px;
    scrollbar-gutter: stable;
}

.usecasedoc-preview-panel {
    border-right: 1px solid #e5e7eb;
}

.usecasedoc-preview-panel .modern-canvas-body {
    padding: 18px;
    display: flex;
    flex-direction: column;
    justify-content: flex-start;
    align-items: stretch;
    background: #fff;
    overflow: hidden;
}

.usecasedoc-preview-shell {
    display: flex;
    flex-direction: column;
    justify-content: flex-start;
    align-items: center;
    min-height: calc(100vh - 120px);
    gap: 10px;
    padding-top: 0;
}

.usecasedoc-example-title {
    margin: 0;
    color: #111827;
    font-size: 18px;
    font-weight: 700;
}

.usecasedoc-example-frame {
    width: min(100%, 820px);
    padding: 14px;
    border: 1px solid #e5e7eb;
    border-radius: 12px;
    background: #fafafa;
    box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.8);
}

.usecasedoc-example-image {
    display: block;
    width: 100%;
    height: auto;
    border: 1px solid #d1d5db;
    border-radius: 10px;
    background: #fff;
}

.usecasedoc-example-tip {
    margin: 0;
    color: #6b7280;
    font-size: 12px;
    text-align: center;
}

.usecasedoc-preset-section {
    margin-bottom: 12px;
    padding: 12px;
    border: 1px solid #e5e7eb;
    border-radius: 10px;
    background: #fafafa;
}

.usecasedoc-preset-header {
    margin-bottom: 8px;
}

.usecasedoc-preset-label {
    display: flex;
    align-items: center;
    gap: 8px;
    margin: 0;
    color: #111827;
    font-size: 13px;
    font-weight: 700;
}

.usecasedoc-preset-select,
.usecasedoc-form-input,
.usecasedoc-form-textarea {
    width: 100%;
    border: 1px solid #d1d5db;
    border-radius: 8px;
    background: #fff;
    color: #111827;
    font-size: 13px;
    transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

.usecasedoc-preset-select {
    padding: 10px 12px;
    margin-bottom: 10px;
}

.usecasedoc-preset-select:focus,
.usecasedoc-form-input:focus,
.usecasedoc-form-textarea:focus {
    border-color: #3b82f6;
    outline: 0;
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.14);
}

.usecasedoc-preset-buttons,
.usecasedoc-action-group {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.usecasedoc-preset-btn {
    flex: 1 1 calc(50% - 4px);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
    padding: 8px 10px;
    width: auto;
    border-radius: 6px;
    font-size: 12px;
    font-weight: 600;
    cursor: pointer;
    transition: background-color 0.2s ease, border-color 0.2s ease, box-shadow 0.2s ease;
}

.usecasedoc-preset-btn-apply {
    background: #2563eb;
    border-color: #2563eb;
    color: #fff;
}

.usecasedoc-preset-btn-apply:hover {
    background: #1d4ed8;
    border-color: #1d4ed8;
}

.usecasedoc-preset-btn-clear {
    background: #f3f4f6;
    border-color: #d1d5db;
    color: #374151;
}

.usecasedoc-preset-btn-clear:hover {
    background: #f8fafc;
    border-color: #94a3b8;
    color: #1f2937;
}

.usecasedoc-form-shell {
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.usecasedoc-form-table-wrap {
    border: 1px solid #e5e7eb;
    border-radius: 12px;
    overflow: hidden;
    background: #fff;
}

.usecasedoc-table-title {
    margin: 0;
    padding: 6px 0 2px;
    color: #111827;
    font-size: 18px;
    font-weight: 700;
    text-align: center;
}

.usecasedoc-form-table {
    width: 100%;
    border-collapse: collapse;
    font-family: "Microsoft YaHei", "PingFang SC", sans-serif;
    border-top: 2px solid #111827;
    border-bottom: 2px solid #111827;
}

.usecasedoc-form-table th,
.usecasedoc-form-table td {
    border-bottom: 1px solid #d1d5db;
    vertical-align: top;
}

.usecasedoc-form-table tr:last-child th,
.usecasedoc-form-table tr:last-child td {
    border-bottom: none;
}

.usecasedoc-form-table th {
    width: 22%;
    padding: 12px 10px;
    border-right: 1px solid #d1d5db;
    background: #f9fafb;
    color: #111827;
    text-align: center;
    font-size: 13px;
    font-weight: 700;
}

.usecasedoc-form-table td {
    width: 78%;
    padding: 10px;
    background: #fff;
}

.usecasedoc-form-input,
.usecasedoc-form-textarea {
    padding: 9px 11px;
    line-height: 1.6;
}

.usecasedoc-form-textarea {
    resize: vertical;
    min-height: 68px;
}

.usecasedoc-textarea-small {
    min-height: 76px;
}

.usecasedoc-textarea-large {
    min-height: 180px;
}

.usecasedoc-inline-actions {
    margin-top: 4px;
}

.usecasedoc-export-button {
    width: 100%;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 8px 10px;
    border-radius: 6px;
    background: #10b981;
    border-color: #10b981;
    color: #fff;
    font-size: 12px;
    font-weight: 600;
    cursor: pointer;
    transition: background-color 0.2s ease, border-color 0.2s ease, box-shadow 0.2s ease;
}

.usecasedoc-export-button:hover {
    background: #059669;
    border-color: #059669;
    color: #fff;
}

.usecasedoc-export-button:disabled {
    opacity: 0.55;
    cursor: not-allowed;
}

.usecasedoc-settings-panel .params-grid {
    display: grid;
    gap: 8px;
}

.usecasedoc-settings-panel .params-column {
    padding: 10px;
    border: 1px solid #e5e7eb;
    border-radius: 10px;
    background: #fafafa;
}

.usecasedoc-settings-panel .params-group-title {
    margin: 0 0 8px;
    color: #111827;
    font-size: 12px;
    font-weight: 700;
}

.usecasedoc-settings-panel .form-group-compact {
    margin-bottom: 8px;
}

.usecasedoc-settings-panel .form-group-compact:last-child {
    margin-bottom: 0;
}

.usecasedoc-shortcut-btn {
    width: 100%;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
    padding: 8px 10px;
    border: 1px solid #d1d5db;
    border-radius: 8px;
    background: #fff;
    color: #374151;
    font-size: 12px;
    font-weight: 700;
    cursor: pointer;
    transition: background-color 0.2s ease, border-color 0.2s ease;
}

.usecasedoc-shortcut-btn:hover {
    background: #f8fafc;
    border-color: #94a3b8;
}

.usecasedoc-shortcut-btn.is-primary {
    background: #2563eb;
    border-color: #2563eb;
    color: #fff;
}

.usecasedoc-shortcut-btn.is-primary:hover {
    background: #1d4ed8;
    border-color: #1d4ed8;
}

.usecasedoc-shortcut-btn.is-success {
    background: #16a34a;
    border-color: #16a34a;
    color: #fff;
}

.usecasedoc-shortcut-btn.is-success:hover {
    background: #15803d;
    border-color: #15803d;
}

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

.usecasedoc-help-list li {
    position: relative;
    margin-bottom: 6px;
    padding-left: 12px;
    color: #475569;
    font-size: 12px;
    line-height: 1.6;
}

.usecasedoc-help-list li:last-child {
    margin-bottom: 0;
}

.usecasedoc-help-list li::before {
    content: "•";
    position: absolute;
    left: 0;
    top: 0;
    color: #94a3b8;
}

.usecasedoc-loading-message {
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    z-index: 9999;
    background: #fff;
    border-radius: 12px;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.25);
    padding: 30px 48px;
    min-width: 300px;
}

.usecasedoc-loading {
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 12px 0;
    color: #6b7280;
}

.usecasedoc-spinner {
    width: 30px;
    height: 30px;
    margin-right: 12px;
    border: 3px solid #e5e7eb;
    border-top-color: #2563eb;
    border-radius: 999px;
    animation: usecasedoc-spin 1s linear infinite;
}

.usecasedoc-loading-message {
    color: #111827;
}

.usecasedoc-message {
    position: fixed;
    top: 110px;
    right: 20px;
    z-index: 1000;
    min-width: 300px;
    max-width: 500px;
    border-radius: 10px;
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.15);
    animation: usecasedoc-slide-in 0.25s ease-out;
}

.usecasedoc-message-content {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 14px 16px;
}

.usecasedoc-message-icon {
    font-size: 18px;
}

.usecasedoc-message-text {
    flex: 1;
    font-size: 13px;
    font-weight: 600;
}

.usecasedoc-message-close {
    background: none;
    border: none;
    color: inherit;
    cursor: pointer;
    opacity: 0.8;
}

.usecasedoc-message-success {
    background: #10b981;
    color: #fff;
}

.usecasedoc-message-error {
    background: #ef4444;
    color: #fff;
}

.usecasedoc-message-warning {
    background: #f59e0b;
    color: #fff;
}

.usecasedoc-message-info {
    background: #3b82f6;
    color: #fff;
}

@keyframes usecasedoc-spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

@keyframes usecasedoc-slide-in {
    from {
        opacity: 0;
        transform: translateX(100%);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

@media (max-width: 1680px) {
    .usecasedoc-page .usecasedoc-workspace {
        grid-template-columns: 132px 580px minmax(0, 1fr) 210px;
    }
}

@media (max-width: 1440px) {
    .usecasedoc-page .usecasedoc-workspace {
        grid-template-columns: 120px 520px minmax(0, 1fr) 200px;
    }
}

@media (max-width: 1200px) {
    .usecasedoc-page .usecasedoc-workspace {
        grid-template-columns: 220px minmax(0, 1fr);
        grid-template-areas:
            "tools preview"
            "input preview"
            "settings settings";
    }

    .usecasedoc-preview-shell {
        min-height: 420px;
    }
}

@media (max-width: 680px), (max-height: 720px) {
    .usecasedoc-preset-btn {
        flex-basis: 100%;
    }
}