:root {
    --bg-color: #fafafa;
    --sidebar-bg: #f0f0f0;
    --text-primary: #1a1a1a;
    --text-secondary: #666;
    --border-color: #e5e5e5;
    --brand-color: #5d3fd3;
    /* Purple-ish, similar to Claude */
    --hover-color: #f1eeff;
    --card-bg: #ffffff;
    --sys-msg-bg: #f9f9f9;
    --user-msg-bg: #ececf1;
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-primary);
    display: flex;
    height: 100vh;
    overflow: hidden;
}

/* App Layout */
.app-container {
    display: flex;
    width: 100%;
    height: 100%;
}

/* Sidebar */
.sidebar {
    width: 280px;
    min-width: 280px;
    background-color: var(--sidebar-bg);
    border-right: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
    padding: 24px 16px;
    overflow-y: auto;
}

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

.sidebar-header h2 {
    font-size: 1.25rem;
    font-weight: 600;
}

.sidebar-section {
    margin-bottom: 24px;
}

.sidebar-section h3 {
    font-size: 0.875rem;
    color: var(--text-secondary);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-bottom: 12px;
}

.file-input,
.num-input {
    width: 100%;
    margin-bottom: 12px;
    padding: 8px;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    font-family: inherit;
    font-size: 0.875rem;
    background: var(--card-bg);
}

.btn {
    width: 100%;
    padding: 10px 16px;
    border: none;
    border-radius: var(--radius-sm);
    font-weight: 500;
    font-size: 0.875rem;
    cursor: pointer;
    transition: all 0.2s ease;
}

.btn.primary {
    background-color: var(--brand-color);
    color: white;
}

.btn.primary:hover {
    background-color: #4b32b0;
}

.btn.secondary {
    background-color: white;
    border: 1px solid var(--border-color);
    color: var(--text-primary);
}

.btn.secondary:hover {
    background-color: var(--hover-color);
    border-color: var(--brand-color);
}

.status-msg {
    font-size: 0.8rem;
    color: var(--text-secondary);
    margin-top: 8px;
    text-align: center;
}

/* Main Content */
.main-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    position: relative;
    max-width: 1200px;
    margin: 0 auto;
    width: 100%;
}

.top-nav {
    padding: 16px 24px;
    border-bottom: 1px solid var(--border-color);
    background-color: var(--bg-color);
    text-align: center;
    position: sticky;
    top: 0;
    z-index: 10;
}

.top-nav h1 {
    font-size: 1.1rem;
    font-weight: 600;
}

.top-nav p {
    font-size: 0.875rem;
    color: var(--text-secondary);
}

/* Chat Area */
.chat-area {
    flex: 1;
    overflow-y: auto;
    padding: 24px;
    display: flex;
    flex-direction: column;
    gap: 32px;
    scroll-behavior: smooth;
}

/* Messages */
.message {
    display: flex;
    flex-direction: column;
    max-width: 100%;
    margin: 0 auto;
    width: 100%;
}

.message.user {
    align-items: flex-end;
}

.user-bubble {
    background-color: var(--user-msg-bg);
    padding: 16px 24px;
    border-radius: 20px 20px 4px 20px;
    max-width: 70%;
    font-size: 1rem;
    line-height: 1.5;
}

.system-responses {
    display: grid;
    grid-template-columns: 1fr 1fr 1fr;
    gap: 24px;
    width: 100%;
}

.response-card {
    background-color: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 24px;
    box-shadow: var(--shadow-sm);
    display: flex;
    flex-direction: column;
}

.response-header {
    display: flex;
    align-items: center;
    gap: 8px;
    margin-bottom: 16px;
    padding-bottom: 12px;
    border-bottom: 1px solid var(--border-color);
}

.response-header span {
    font-weight: 600;
    font-size: 0.95rem;
    color: var(--brand-color);
}

.response-content {
    flex: 1;
    font-size: 0.95rem;
    line-height: 1.6;
    color: var(--text-primary);
}

.response-content p {
    margin-bottom: 1em;
}

.response-content ul,
.response-content ol {
    margin-bottom: 1em;
    padding-left: 20px;
}

.response-content code {
    background-color: rgba(0, 0, 0, 0.05);
    padding: 0.2em 0.4em;
    border-radius: 4px;
    font-family: monospace;
    font-size: 0.9em;
}

/* Metrics UI */
.metrics {
    margin-top: 16px;
    padding-top: 16px;
    border-top: 1px dashed var(--border-color);
    display: flex;
    flex-direction: column;
    gap: 8px;
    font-size: 0.8rem;
    color: var(--text-secondary);
}

.metrics-row {
    display: flex;
    justify-content: space-between;
}

.sources-container {
    margin-top: 12px;
}

.sources-toggle {
    background: none;
    border: none;
    color: var(--brand-color);
    font-size: 0.8rem;
    font-weight: 500;
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 4px;
}

.sources-toggle:hover {
    text-decoration: underline;
}

.sources-list {
    margin-top: 8px;
    display: none;
    background: var(--bg-color);
    padding: 12px;
    border-radius: var(--radius-sm);
    border: 1px solid var(--border-color);
    max-height: 200px;
    overflow-y: auto;
}

.sources-list.open {
    display: block;
}

.source-item {
    margin-bottom: 12px;
    padding-bottom: 12px;
    border-bottom: 1px dashed var(--border-color);
}

.source-item:last-child {
    border-bottom: none;
    margin-bottom: 0;
    padding-bottom: 0;
}

.source-meta {
    font-weight: 600;
    display: block;
    margin-bottom: 4px;
    color: var(--text-primary);
}

/* Input Area */
.input-area {
    padding: 24px;
    background: linear-gradient(to top, var(--bg-color) 80%, transparent);
    position: sticky;
    bottom: 0;
}

.input-wrapper {
    max-width: 800px;
    margin: 0 auto;
    background-color: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-md);
    padding: 12px 16px;
    display: flex;
    align-items: flex-end;
    transition: border-color 0.2s;
}

.input-wrapper:focus-within {
    border-color: var(--brand-color);
}

#prompt-input {
    flex: 1;
    border: none;
    background: transparent;
    font-family: inherit;
    font-size: 1rem;
    line-height: 1.5;
    resize: none;
    outline: none;
    max-height: 200px;
    padding: 4px 0;
}

.send-btn {
    background: var(--brand-color);
    color: white;
    border: none;
    border-radius: var(--radius-sm);
    width: 36px;
    height: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: background-color 0.2s;
    flex-shrink: 0;
    margin-left: 12px;
}

.send-btn:hover {
    background-color: #4b32b0;
}

.send-btn:disabled {
    background-color: var(--border-color);
    cursor: not-allowed;
}

/* Loader */
.typing-indicator {
    display: inline-block;
    width: 4px;
    height: 1em;
    background-color: var(--text-primary);
    animation: blink 1s step-end infinite;
    vertical-align: middle;
}

@keyframes blink {
    50% {
        opacity: 0;
    }
}

/* Documents Grid */
.documents-grid {
    margin-top: 16px;
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(100px, 1fr));
    gap: 12px;
}

.document-card {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 12px 8px;
    text-align: center;
    box-shadow: 0 1px 2px rgba(0, 0, 0, 0.02);
    transition: transform 0.2s, box-shadow 0.2s;
}

.document-card:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-sm);
    border-color: var(--brand-color);
}

.doc-icon {
    width: 32px;
    height: 32px;
    margin-bottom: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 4px;
    font-weight: bold;
    font-size: 0.75rem;
    color: white;
}

.icon-pdf {
    background-color: #e53935;
}

.icon-docx {
    background-color: #1e88e5;
}

.icon-txt {
    background-color: #757575;
}

.icon-default {
    background-color: #9e9e9e;
}

.doc-name {
    font-size: 0.75rem;
    font-weight: 500;
    width: 100%;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.doc-size {
    font-size: 0.65rem;
    color: var(--text-secondary);
    margin-top: 4px;
}

.spinner {
    display: inline-block;
    width: 16px;
    height: 16px;
    border: 2px solid rgba(0, 0, 0, 0.1);
    border-left-color: var(--brand-color);
    border-radius: 50%;
    animation: spin 1s linear infinite;
    vertical-align: middle;
    margin-right: 8px;
}

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


/* Full-Screen Loading Overlay */
.overlay {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(250, 250, 250, 0.85);
    /* Frosty var(--bg-color) */
    backdrop-filter: blur(4px);
    z-index: 100;
    display: flex;
    align-items: center;
    justify-content: center;
}

.overlay-content {
    background: var(--card-bg);
    padding: 32px 48px;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-md);
    border: 1px solid var(--border-color);
    text-align: center;
    max-width: 400px;
}

.overlay-content h2 {
    font-size: 1.25rem;
    margin-bottom: 8px;
    font-weight: 600;
}

.overlay-content p {
    font-size: 0.9rem;
    color: var(--text-secondary);
}

.large-spinner {
    width: 32px;
    height: 32px;
    border-width: 3px;
    margin: 0 auto 16px;
    display: block;
}

.doc-thumbnail {
    width: 100%;
    height: 80px;
    object-fit: cover;
    border-radius: 4px;
    margin-bottom: 8px;
    background-color: var(--sidebar-bg);
    border: 1px solid var(--border-color);
}

/* Token Badges */
.token-badges {
    display: flex;
    gap: 8px;
    align-items: center;
}

.badge {
    padding: 2px 8px;
    border-radius: 12px;
    font-size: 0.75rem;
    font-weight: 500;
    font-family: monospace;
}

.prompt-badge {
    background-color: #e0f2fe;
    color: #0369a1;
    border: 1px solid #bae6fd;
}

.completion-badge {
    background-color: #fce7f3;
    color: #be185d;
    border: 1px solid #fbcfe8;
}

/* Modal Styles */
.modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background: rgba(0, 0, 0, 0.5);
    backdrop-filter: blur(4px);
    z-index: 1000;
    display: flex;
    align-items: center;
    justify-content: center;
}

.modal-content {
    background: var(--bg-color);
    width: 90vw;
    height: 90vh;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-md);
    display: flex;
    flex-direction: column;
    overflow: hidden;
}

.modal-header {
    padding: 24px;
    border-bottom: 1px solid var(--border-color);
    display: flex;
    justify-content: space-between;
    align-items: center;
    background: var(--card-bg);
}

.modal-header h2 {
    font-size: 1.25rem;
    font-weight: 600;
}

.close-btn {
    background: none;
    border: none;
    font-size: 2rem;
    cursor: pointer;
    color: var(--text-secondary);
    transition: color 0.2s;
    line-height: 1;
}

.close-btn:hover {
    color: var(--text-primary);
}

.modal-body {
    flex: 1;
    overflow: hidden;
    padding: 24px;
}

.comparison-container {
    display: flex;
    gap: 24px;
    height: 100%;
}

.chunk-column {
    flex: 1;
    display: flex;
    flex-direction: column;
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    overflow: hidden;
}

.column-header {
    padding: 16px;
    background: var(--sidebar-bg);
    border-bottom: 1px solid var(--border-color);
    font-weight: 600;
    font-size: 0.95rem;
    color: var(--brand-color);
    text-align: center;
}

.chunks-list {
    flex: 1;
    overflow-y: auto;
    padding: 16px;
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.chunk-item {
    background: var(--user-msg-bg);
    border-radius: var(--radius-sm);
    padding: 16px;
    font-size: 0.9rem;
    line-height: 1.5;
    border: 1px solid transparent;
    transition: border-color 0.2s;
}

.chunk-item:hover {
    border-color: var(--brand-color);
}

.chunk-meta {
    font-weight: 600;
    color: var(--brand-color);
    margin-bottom: 8px;
    display: block;
    font-size: 0.8rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.chunk-text {
    white-space: pre-wrap;
    word-break: break-word;
}

/* Modal Styles */
.modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background: rgba(0, 0, 0, 0.5);
    backdrop-filter: blur(4px);
    z-index: 1000;
    display: flex;
    align-items: center;
    justify-content: center;
}

.modal-content {
    background: var(--bg-color);
    width: 90vw;
    height: 90vh;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-md);
    display: flex;
    flex-direction: column;
    overflow: hidden;
}

.modal-header {
    padding: 24px;
    border-bottom: 1px solid var(--border-color);
    display: flex;
    justify-content: space-between;
    align-items: center;
    background: var(--card-bg);
}

.modal-header h2 {
    font-size: 1.25rem;
    font-weight: 600;
}

.close-btn {
    background: none;
    border: none;
    font-size: 2rem;
    cursor: pointer;
    color: var(--text-secondary);
    transition: color 0.2s;
    line-height: 1;
}

.close-btn:hover {
    color: var(--text-primary);
}

.modal-body {
    flex: 1;
    overflow: hidden;
    padding: 24px;
}

.comparison-container {
    display: flex;
    gap: 24px;
    height: 100%;
}

.chunk-column {
    flex: 1;
    display: flex;
    flex-direction: column;
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    overflow: hidden;
}

.column-header {
    padding: 16px;
    background: var(--sidebar-bg);
    border-bottom: 1px solid var(--border-color);
    font-weight: 600;
    font-size: 0.95rem;
    color: var(--brand-color);
    text-align: center;
}

.chunks-list {
    flex: 1;
    overflow-y: auto;
    padding: 16px;
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.chunk-item {
    background: var(--user-msg-bg);
    border-radius: var(--radius-sm);
    padding: 16px;
    font-size: 0.9rem;
    line-height: 1.5;
    border: 1px solid transparent;
    transition: border-color 0.2s;
}

.chunk-item:hover {
    border-color: var(--brand-color);
}

.chunk-meta {
    font-weight: 600;
    color: var(--brand-color);
    margin-bottom: 8px;
    display: block;
    font-size: 0.8rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.chunk-text {
    white-space: pre-wrap;
    word-break: break-word;
}

/* Cost Tracking Sidebar */
.cost-stats {
    display: flex;
    flex-direction: column;
    gap: 6px;
    font-size: 0.85rem;
    padding: 8px 0;
}

.cost-stats div {
    display: flex;
    justify-content: space-between;
}

.cost-label {
    color: var(--secondary-text);
}

.cost-value {
    font-family: monospace;
    color: var(--text-color);
}

.cost-total-row {
    margin-top: 6px;
    padding-top: 6px;
    border-top: 1px dashed var(--border-color);
}

.cost-total {
    font-weight: bold;
    color: #10b981;
}