:root {
    --bg-primary: #1a1a1a;
    --bg-secondary: #2d2d2d;
    --bg-tertiary: #3d3d3d;
    --bg-hover: #4d4d4d;
    --text-primary: #e4e4e7;
    --text-secondary: #a1a1aa;
    --border-color: #404040;
    --accent-color: #10b981;
    --accent-hover: #059669;
    --user-bg: #2563eb;
    --assistant-bg: #7c3aed;
    --card-bg: #2d2d2d;
    --input-bg: #3d3d3d;
    --shadow: rgba(0, 0, 0, 0.3);
    --sidebar-width: 280px;
}

[data-theme="light"] {
    --bg-primary: #ffffff;
    --bg-secondary: #f9fafb;
    --bg-tertiary: #f3f4f6;
    --bg-hover: #e5e7eb;
    --text-primary: #1f2937;
    --text-secondary: #6b7280;
    --border-color: #e5e7eb;
    --accent-color: #10b981;
    --accent-hover: #059669;
    --user-bg: #3b82f6;
    --assistant-bg: #8b5cf6;
    --card-bg: #ffffff;
    --input-bg: #f9fafb;
    --shadow: rgba(0, 0, 0, 0.1);
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen', 'Ubuntu', 'Cantarell', sans-serif;
    background-color: var(--bg-primary);
    color: var(--text-primary);
    height: 100vh;
    display: flex;
    overflow: hidden;
    transition: background-color 0.3s ease, color 0.3s ease;
}

.app-container {
    display: flex;
    width: 100%;
    height: 100vh;
}

/* Sidebar Styles */
.sidebar {
    width: var(--sidebar-width);
    background-color: var(--bg-secondary);
    display: flex;
    flex-direction: column;
    border-right: 1px solid var(--border-color);
    transition: transform 0.3s ease, background-color 0.3s ease;
    position: relative;
    z-index: 100;
}

.sidebar.collapsed {
    transform: translateX(calc(-1 * var(--sidebar-width)));
}

.sidebar-header {
    padding: 16px;
    border-bottom: 1px solid var(--border-color);
}

.new-chat-button {
    width: 100%;
    padding: 14px 16px;
    background: linear-gradient(135deg, var(--accent-color), var(--accent-hover));
    border: none;
    border-radius: 8px;
    color: white;
    cursor: pointer;
    font-size: 15px;
    font-weight: 600;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    transition: transform 0.2s, box-shadow 0.2s;
    box-shadow: 0 2px 8px var(--shadow);
}

.new-chat-button:hover {
    transform: translateY(-1px);
    box-shadow: 0 4px 12px var(--shadow);
}

.new-chat-button:active {
    transform: translateY(0);
}

.chat-list {
    flex: 1;
    overflow-y: auto;
    padding: 12px;
}

.chat-list::-webkit-scrollbar {
    width: 6px;
}

.chat-list::-webkit-scrollbar-track {
    background: transparent;
}

.chat-list::-webkit-scrollbar-thumb {
    background: var(--border-color);
    border-radius: 3px;
}

.chat-item {
    padding: 12px 14px;
    margin-bottom: 6px;
    background-color: transparent;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.2s;
    font-size: 14px;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 8px;
    border: 1px solid transparent;
}

.chat-item:hover {
    background-color: var(--bg-tertiary);
    border-color: var(--border-color);
}

.chat-item.active {
    background-color: var(--bg-tertiary);
    border-color: var(--accent-color);
    font-weight: 500;
}

.chat-item-title {
    flex: 1;
    overflow: hidden;
    text-overflow: ellipsis;
    color: var(--text-primary);
}

.delete-chat-button {
    opacity: 0;
    background: none;
    border: none;
    color: var(--text-secondary);
    cursor: pointer;
    padding: 4px 8px;
    font-size: 16px;
    transition: opacity 0.2s, color 0.2s;
    border-radius: 4px;
}

.chat-item:hover .delete-chat-button {
    opacity: 1;
}

.delete-chat-button:hover {
    color: #ef4444;
    background-color: rgba(239, 68, 68, 0.1);
}

.main-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    position: relative;
    transition: margin-left 0.3s ease;
}

.sidebar.collapsed ~ .main-content {
    margin-left: calc(-1 * var(--sidebar-width));
}

.sidebar-toggle {
    position: absolute;
    top: 16px;
    left: 16px;
    z-index: 10;
    background-color: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 10px 14px;
    color: var(--text-primary);
    cursor: pointer;
    font-size: 18px;
    transition: all 0.2s;
    box-shadow: 0 2px 8px var(--shadow);
}

.sidebar-toggle:hover {
    background-color: var(--bg-tertiary);
    transform: scale(1.05);
}

.header {
    background-color: var(--bg-secondary);
    padding: 16px 24px;
    padding-left: 70px;
    border-bottom: 1px solid var(--border-color);
    display: flex;
    align-items: center;
    justify-content: space-between;
    box-shadow: 0 1px 3px var(--shadow);
    transition: padding-left 0.3s ease;
}

.sidebar.collapsed ~ .main-content .header {
    padding-left: 70px;
}

.header h1 {
    font-size: 20px;
    font-weight: 700;
    color: var(--text-primary);
    display: flex;
    align-items: center;
    gap: 10px;
}

.header-buttons {
    display: flex;
    gap: 12px;
    align-items: center;
}

.theme-toggle {
    background-color: var(--bg-tertiary);
    color: var(--text-primary);
    border: 1px solid var(--border-color);
    padding: 10px 16px;
    border-radius: 8px;
    font-size: 20px;
    cursor: pointer;
    outline: none;
    transition: all 0.2s;
    display: flex;
    align-items: center;
    justify-content: center;
}

.theme-toggle:hover {
    background-color: var(--bg-hover);
    transform: scale(1.05);
}

.model-selector {
    background-color: var(--bg-tertiary);
    color: var(--text-primary);
    border: 1px solid var(--border-color);
    padding: 10px 14px;
    border-radius: 8px;
    font-size: 14px;
    cursor: pointer;
    outline: none;
    transition: all 0.2s;
    font-weight: 500;
}

.model-selector:hover {
    background-color: var(--bg-hover);
    border-color: var(--accent-color);
}

.model-selector:focus {
    border-color: var(--accent-color);
    box-shadow: 0 0 0 3px rgba(16, 185, 129, 0.1);
}

.reset-button, .debug-toggle {
    background-color: var(--bg-tertiary);
    color: var(--text-primary);
    border: 1px solid var(--border-color);
    padding: 10px 16px;
    border-radius: 8px;
    cursor: pointer;
    font-size: 14px;
    font-weight: 500;
    transition: all 0.2s;
}

.reset-button:hover, .debug-toggle:hover {
    background-color: var(--bg-hover);
    border-color: var(--accent-color);
}

.chat-container {
    flex: 1;
    overflow-y: auto;
    padding: 24px;
    display: flex;
    flex-direction: column;
    gap: 24px;
}

.chat-container::-webkit-scrollbar {
    width: 8px;
}

.chat-container::-webkit-scrollbar-track {
    background: transparent;
}

.chat-container::-webkit-scrollbar-thumb {
    background: var(--border-color);
    border-radius: 4px;
}

.message {
    display: flex;
    gap: 16px;
    padding: 24px;
    max-width: 900px;
    margin: 0 auto;
    width: 100%;
    border-radius: 12px;
    transition: all 0.3s;
}

.message.user {
    background-color: var(--card-bg);
    border: 1px solid var(--border-color);
    box-shadow: 0 2px 8px var(--shadow);
}

.message.assistant {
    background-color: var(--card-bg);
    border: 1px solid var(--border-color);
    box-shadow: 0 2px 8px var(--shadow);
}

.avatar {
    width: 36px;
    height: 36px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    font-weight: 700;
    font-size: 16px;
    box-shadow: 0 2px 8px var(--shadow);
}

.avatar.user {
    background: linear-gradient(135deg, #3b82f6, #2563eb);
    color: white;
}

.avatar.assistant {
    background: linear-gradient(135deg, #8b5cf6, #7c3aed);
    color: white;
}

.message-content {
    flex: 1;
    line-height: 1.7;
    white-space: pre-wrap;
    color: var(--text-primary);
}

.input-container {
    background-color: var(--bg-secondary);
    padding: 20px;
    border-top: 1px solid var(--border-color);
    box-shadow: 0 -2px 10px var(--shadow);
}

.input-wrapper {
    max-width: 900px;
    margin: 0 auto;
    position: relative;
    background-color: var(--input-bg);
    border-radius: 12px;
    box-shadow: 0 2px 12px var(--shadow);
    border: 2px solid var(--border-color);
    transition: all 0.2s;
}

.input-wrapper:focus-within {
    border-color: var(--accent-color);
    box-shadow: 0 4px 16px var(--shadow);
}

.input-box {
    width: 100%;
    padding: 18px 56px 18px 18px;
    background-color: transparent;
    border: none;
    color: var(--text-primary);
    font-size: 16px;
    resize: none;
    outline: none;
    font-family: inherit;
    min-height: 24px;
    max-height: 200px;
}

.input-box::placeholder {
    color: var(--text-secondary);
}

.send-button {
    position: absolute;
    right: 14px;
    bottom: 14px;
    width: 40px;
    height: 40px;
    background: linear-gradient(135deg, var(--accent-color), var(--accent-hover));
    border: none;
    border-radius: 8px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.2s;
    box-shadow: 0 2px 8px var(--shadow);
}

.send-button:hover:not(:disabled) {
    transform: scale(1.05);
    box-shadow: 0 4px 12px var(--shadow);
}

.send-button:disabled {
    background: var(--bg-hover);
    cursor: not-allowed;
    opacity: 0.5;
}

.send-button svg {
    width: 20px;
    height: 20px;
    fill: white;
}

.loading {
    display: flex;
    gap: 6px;
    padding: 12px 0;
}

.loading-dot {
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background-color: var(--accent-color);
    animation: bounce 1.4s infinite ease-in-out both;
}

.loading-dot:nth-child(1) {
    animation-delay: -0.32s;
}

.loading-dot:nth-child(2) {
    animation-delay: -0.16s;
}

@keyframes bounce {
    0%, 80%, 100% {
        transform: scale(0);
    }
    40% {
        transform: scale(1);
    }
}

.sparql-query {
    margin-top: 16px;
    padding: 16px;
    background-color: var(--bg-tertiary);
    border-radius: 8px;
    font-family: 'Courier New', monospace;
    font-size: 13px;
    color: var(--text-primary);
    overflow-x: auto;
    border: 1px solid var(--border-color);
}

.sparql-label {
    color: var(--text-secondary);
    font-size: 12px;
    margin-bottom: 8px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.welcome-screen {
    max-width: 900px;
    margin: auto;
    padding: 60px 20px;
    text-align: center;
}

.welcome-screen h2 {
    font-size: 36px;
    margin-bottom: 16px;
    background: linear-gradient(135deg, var(--accent-color), var(--user-bg));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    font-weight: 800;
}

.welcome-subtitle {
    color: var(--text-secondary);
    font-size: 16px;
    margin-bottom: 48px;
}

.examples {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 16px;
}

.example-card {
    background-color: var(--card-bg);
    padding: 24px;
    border-radius: 12px;
    cursor: pointer;
    transition: all 0.3s;
    border: 2px solid var(--border-color);
    box-shadow: 0 2px 8px var(--shadow);
}

.example-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 8px 24px var(--shadow);
    border-color: var(--accent-color);
}

.example-title {
    font-weight: 700;
    margin-bottom: 12px;
    font-size: 16px;
    color: var(--text-primary);
}

.example-text {
    color: var(--text-secondary);
    font-size: 14px;
    line-height: 1.5;
}

/* Stage Indicator Styles */
.stage-container {
    display: flex;
    flex-direction: column;
    gap: 8px;
    padding: 12px 0;
}

.stage-item {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 10px 16px;
    border-radius: 8px;
    background-color: var(--bg-tertiary);
    transition: all 0.3s ease;
    opacity: 0.5;
}

.stage-item.pending {
    opacity: 0.4;
    transform: scale(0.98);
}

.stage-item.active {
    opacity: 1;
    transform: scale(1);
    background: linear-gradient(135deg, rgba(16, 185, 129, 0.15), rgba(37, 99, 235, 0.15));
    border: 1px solid var(--accent-color);
    animation: pulseStage 1.5s ease-in-out infinite;
}

.stage-item.completed {
    opacity: 0.7;
    background-color: var(--bg-secondary);
}

.stage-item.completed .stage-icon::after {
    content: ' ✓';
    color: var(--accent-color);
    font-weight: bold;
    margin-left: 4px;
}

.stage-icon {
    font-size: 20px;
    min-width: 24px;
    text-align: center;
}

.stage-text {
    font-size: 14px;
    font-weight: 500;
    color: var(--text-primary);
}

.stage-item.active .stage-text {
    color: var(--accent-color);
    font-weight: 600;
}

@keyframes pulseStage {
    0%, 100% {
        box-shadow: 0 0 0 0 rgba(16, 185, 129, 0.4);
    }
    50% {
        box-shadow: 0 0 0 6px rgba(16, 185, 129, 0);
    }
}

/* Technical Details Section */
.technical-details {
    margin-top: 16px;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    background-color: var(--bg-tertiary);
    overflow: hidden;
}

.technical-summary {
    padding: 12px 16px;
    cursor: pointer;
    font-weight: 600;
    font-size: 14px;
    color: var(--text-secondary);
    background-color: var(--bg-secondary);
    transition: all 0.2s;
    user-select: none;
    display: flex;
    align-items: center;
    gap: 8px;
}

.technical-summary:hover {
    background-color: var(--bg-hover);
    color: var(--accent-color);
}

.technical-summary::before {
    content: '▶';
    display: inline-block;
    transition: transform 0.2s;
    font-size: 10px;
}

.technical-details[open] .technical-summary::before {
    transform: rotate(90deg);
}

.technical-content {
    padding: 16px;
    margin: 0;
    font-family: 'Monaco', 'Menlo', 'Ubuntu Mono', 'Consolas', 'source-code-pro', monospace;
    font-size: 12px;
    line-height: 1.6;
    color: var(--text-primary);
    background-color: var(--bg-tertiary);
    overflow-x: auto;
    white-space: pre-wrap;
    word-wrap: break-word;
    border-top: 1px solid var(--border-color);
}

.technical-content::-webkit-scrollbar {
    height: 8px;
}

.technical-content::-webkit-scrollbar-track {
    background: var(--bg-secondary);
    border-radius: 4px;
}

.technical-content::-webkit-scrollbar-thumb {
    background: var(--border-color);
    border-radius: 4px;
}

.technical-content::-webkit-scrollbar-thumb:hover {
    background: var(--accent-color);
}

.credits-bar {
    text-align: center;
    margin-top: 10px;
    font-size: 12px;
    color: var(--text-secondary);
    letter-spacing: 0.02em;
}