/* UPSC RAG Chatbot Styles */
/* Modern, premium design with dark mode */

:root {
    /* Color Palette */
    --primary-hue: 220;
    --primary: hsl(var(--primary-hue), 90%, 56%);
    --primary-light: hsl(var(--primary-hue), 90%, 65%);
    --primary-dark: hsl(var(--primary-hue), 90%, 45%);
    --primary-glow: hsla(var(--primary-hue), 90%, 56%, 0.3);
    
    --accent-hue: 160;
    --accent: hsl(var(--accent-hue), 80%, 45%);
    --accent-light: hsl(var(--accent-hue), 80%, 55%);
    
    /* Dark theme */
    --bg-primary: hsl(225, 20%, 8%);
    --bg-secondary: hsl(225, 20%, 12%);
    --bg-tertiary: hsl(225, 20%, 16%);
    --bg-elevated: hsl(225, 20%, 18%);
    
    --text-primary: hsl(220, 15%, 95%);
    --text-secondary: hsl(220, 10%, 70%);
    --text-muted: hsl(220, 10%, 50%);
    
    --border-color: hsl(220, 15%, 20%);
    --border-subtle: hsl(220, 15%, 15%);
    
    /* Shadows */
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.3);
    --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.5);
    --shadow-glow: 0 0 20px var(--primary-glow);
    
    /* Spacing */
    --space-xs: 0.25rem;
    --space-sm: 0.5rem;
    --space-md: 1rem;
    --space-lg: 1.5rem;
    --space-xl: 2rem;
    --space-2xl: 3rem;
    
    /* Border radius */
    --radius-sm: 6px;
    --radius-md: 10px;
    --radius-lg: 16px;
    --radius-full: 9999px;
    
    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-normal: 250ms ease;
    --transition-slow: 400ms ease;
    
    /* Typography */
    --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    
    /* Layout */
    --sidebar-width: 280px;
    --header-height: 60px;
}

/* Reset */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    font-size: 16px;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: var(--font-sans);
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
    overflow: hidden;
}

/* App Layout */
.app-container {
    display: flex;
    height: 100vh;
    overflow: hidden;
}

/* Sidebar */
.sidebar {
    width: var(--sidebar-width);
    background: var(--bg-secondary);
    border-right: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
    transition: transform var(--transition-normal);
}

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

.logo {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
}

.logo-icon {
    width: 32px;
    height: 32px;
    color: var(--primary);
}

.logo-text {
    font-size: 1.125rem;
    font-weight: 600;
    background: linear-gradient(135deg, var(--primary), var(--accent));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.sidebar-content {
    flex: 1;
    padding: var(--space-lg);
    overflow-y: auto;
}

.filter-section {
    margin-bottom: var(--space-xl);
}

.filter-title {
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--text-muted);
    margin-bottom: var(--space-sm);
}

.filter-select {
    width: 100%;
    padding: var(--space-sm) var(--space-md);
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    color: var(--text-primary);
    font-family: inherit;
    font-size: 0.875rem;
    cursor: pointer;
    transition: border-color var(--transition-fast);
}

.filter-select:hover,
.filter-select:focus {
    border-color: var(--primary);
    outline: none;
}

.quick-topics {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-xs);
}

.topic-btn {
    padding: var(--space-xs) var(--space-sm);
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-full);
    color: var(--text-secondary);
    font-size: 0.75rem;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.topic-btn:hover {
    background: var(--primary);
    border-color: var(--primary);
    color: white;
}

.sidebar-footer {
    padding: var(--space-lg);
    border-top: 1px solid var(--border-color);
}

.clear-btn {
    width: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-sm);
    padding: var(--space-sm) var(--space-md);
    background: transparent;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    color: var(--text-secondary);
    font-family: inherit;
    font-size: 0.875rem;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.clear-btn svg {
    width: 16px;
    height: 16px;
}

.clear-btn:hover {
    background: hsl(0, 70%, 50%);
    border-color: hsl(0, 70%, 50%);
    color: white;
}

/* Main Chat Area */
.chat-container {
    flex: 1;
    display: flex;
    flex-direction: column;
    min-width: 0;
}

.chat-header {
    height: var(--header-height);
    padding: 0 var(--space-lg);
    background: var(--bg-secondary);
    border-bottom: 1px solid var(--border-color);
    display: flex;
    align-items: center;
    gap: var(--space-md);
}

.menu-toggle {
    display: none;
    background: transparent;
    border: none;
    color: var(--text-secondary);
    cursor: pointer;
    padding: var(--space-sm);
}

.menu-toggle svg {
    width: 24px;
    height: 24px;
}

.chat-title {
    flex: 1;
    font-size: 1.125rem;
    font-weight: 600;
}

.status-indicator {
    display: flex;
    align-items: center;
    gap: var(--space-xs);
    font-size: 0.75rem;
    color: var(--text-muted);
}

.status-dot {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: var(--accent);
    animation: pulse 2s infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.5; }
}

.status-indicator.loading .status-dot {
    background: var(--primary);
    animation: blink 0.5s infinite;
}

@keyframes blink {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.3; }
}

/* Messages */
.messages-container {
    flex: 1;
    overflow-y: auto;
    padding: var(--space-xl);
    display: flex;
    flex-direction: column;
    gap: var(--space-lg);
}

.welcome-message {
    text-align: center;
    padding: var(--space-2xl);
    max-width: 600px;
    margin: auto;
}

.welcome-icon {
    width: 80px;
    height: 80px;
    margin: 0 auto var(--space-lg);
    background: linear-gradient(135deg, var(--primary), var(--accent));
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
}

.welcome-icon svg {
    width: 48px;
    height: 48px;
    color: white;
}

.welcome-message h2 {
    font-size: 1.5rem;
    margin-bottom: var(--space-sm);
}

.welcome-message p {
    color: var(--text-secondary);
    margin-bottom: var(--space-lg);
}

.welcome-subjects {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: var(--space-sm);
}

.subject-tag {
    padding: var(--space-xs) var(--space-md);
    background: var(--bg-tertiary);
    border-radius: var(--radius-full);
    font-size: 0.875rem;
    color: var(--text-secondary);
}

/* Message Bubbles */
.message {
    display: flex;
    gap: var(--space-md);
    max-width: 900px;
    animation: fadeIn var(--transition-normal);
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

.message.user {
    flex-direction: row-reverse;
    margin-left: auto;
}

.message-avatar {
    width: 36px;
    height: 36px;
    border-radius: var(--radius-md);
    background: var(--bg-tertiary);
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.message.user .message-avatar {
    background: var(--primary);
}

.message-avatar svg {
    width: 20px;
    height: 20px;
    color: var(--text-secondary);
}

.message.user .message-avatar svg {
    color: white;
}

.message-content {
    flex: 1;
    min-width: 0;
}

.message-bubble {
    padding: var(--space-md) var(--space-lg);
    background: var(--bg-tertiary);
    border-radius: var(--radius-lg);
    border: 1px solid var(--border-subtle);
}

.message.user .message-bubble {
    background: var(--primary);
    border-color: var(--primary);
}

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

.message-text strong {
    color: var(--primary-light);
}

.message.user .message-text strong {
    color: white;
}

/* Sources Panel */
.sources-panel {
    margin-top: var(--space-sm);
    padding: var(--space-md);
    background: var(--bg-elevated);
    border-radius: var(--radius-md);
    border: 1px solid var(--border-subtle);
}

.sources-header {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
    margin-bottom: var(--space-sm);
    font-size: 0.75rem;
    font-weight: 600;
    color: var(--accent);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    cursor: pointer;
}

.sources-header svg {
    width: 14px;
    height: 14px;
    transition: transform var(--transition-fast);
}

.sources-panel.expanded .sources-header svg {
    transform: rotate(180deg);
}

.sources-list {
    display: none;
}

.sources-panel.expanded .sources-list {
    display: block;
}

.source-item {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
    padding: var(--space-xs) 0;
    font-size: 0.8125rem;
    color: var(--text-secondary);
}

.source-item::before {
    content: '•';
    color: var(--accent);
}

.source-score {
    margin-left: auto;
    padding: 2px 6px;
    background: var(--bg-tertiary);
    border-radius: var(--radius-sm);
    font-size: 0.6875rem;
    color: var(--text-muted);
}

/* Input Area */
.input-container {
    padding: var(--space-lg);
    background: var(--bg-secondary);
    border-top: 1px solid var(--border-color);
}

.chat-form {
    max-width: 900px;
    margin: 0 auto;
}

.input-wrapper {
    display: flex;
    gap: var(--space-sm);
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: var(--space-sm);
    transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.input-wrapper:focus-within {
    border-color: var(--primary);
    box-shadow: var(--shadow-glow);
}

.question-input {
    flex: 1;
    background: transparent;
    border: none;
    color: var(--text-primary);
    font-family: inherit;
    font-size: 1rem;
    padding: var(--space-sm);
    resize: none;
    min-height: 24px;
    max-height: 150px;
}

.question-input::placeholder {
    color: var(--text-muted);
}

.question-input:focus {
    outline: none;
}

.send-btn {
    width: 44px;
    height: 44px;
    background: var(--primary);
    border: none;
    border-radius: var(--radius-md);
    color: white;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    transition: background var(--transition-fast), transform var(--transition-fast);
}

.send-btn:hover:not(:disabled) {
    background: var(--primary-light);
    transform: scale(1.05);
}

.send-btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

.send-btn svg {
    width: 20px;
    height: 20px;
}

.input-hint {
    text-align: center;
    margin-top: var(--space-sm);
    font-size: 0.75rem;
    color: var(--text-muted);
}

/* Loading Animation */
.typing-indicator {
    display: flex;
    gap: 4px;
    padding: var(--space-sm);
}

.typing-indicator span {
    width: 8px;
    height: 8px;
    background: var(--text-muted);
    border-radius: 50%;
    animation: typing 1.4s infinite ease-in-out;
}

.typing-indicator span:nth-child(2) {
    animation-delay: 0.2s;
}

.typing-indicator span:nth-child(3) {
    animation-delay: 0.4s;
}

@keyframes typing {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-4px); }
}

/* Markdown Styling */
.message-text h1, .message-text h2, .message-text h3 {
    margin-top: var(--space-md);
    margin-bottom: var(--space-sm);
    font-weight: 600;
}

.message-text h1 { font-size: 1.25rem; }
.message-text h2 { font-size: 1.125rem; }
.message-text h3 { font-size: 1rem; }

.message-text ul, .message-text ol {
    margin-left: var(--space-lg);
    margin-bottom: var(--space-sm);
}

.message-text li {
    margin-bottom: var(--space-xs);
}

.message-text code {
    background: var(--bg-primary);
    padding: 2px 6px;
    border-radius: var(--radius-sm);
    font-size: 0.875em;
}

.message-text blockquote {
    border-left: 3px solid var(--primary);
    padding-left: var(--space-md);
    margin: var(--space-sm) 0;
    color: var(--text-secondary);
}

/* Responsive */
@media (max-width: 768px) {
    .sidebar {
        position: fixed;
        left: 0;
        top: 0;
        bottom: 0;
        z-index: 100;
        transform: translateX(-100%);
    }
    
    .sidebar.open {
        transform: translateX(0);
    }
    
    .menu-toggle {
        display: block;
    }
    
    .messages-container {
        padding: var(--space-md);
    }
    
    .input-container {
        padding: var(--space-md);
    }
}

/* Scrollbar */
::-webkit-scrollbar {
    width: 6px;
}

::-webkit-scrollbar-track {
    background: transparent;
}

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

::-webkit-scrollbar-thumb:hover {
    background: var(--text-muted);
}