/* CSS Variables - Design System */
/* Light Theme (Default) - Professional, Neutral Design */
:root {
    /* Primary Colors - Neutral Blue (NOT Canada Red) */
    --color-primary: #2563eb;
    --color-primary-dark: #1d4ed8;
    --color-primary-light: #3b82f6;

    /* Secondary */
    --color-secondary: #475569;
    --color-secondary-light: #64748b;

    /* Accent */
    --color-accent: #0ea5e9;

    /* Background Colors - Light Theme */
    --color-bg: #ffffff;
    --color-bg-secondary: #f8fafc;
    --color-bg-card: #ffffff;
    --color-bg-input: #f1f5f9;

    /* Text Colors */
    --color-text: #1e293b;
    --color-text-secondary: #475569;
    --color-text-muted: #94a3b8;

    /* Border Colors */
    --color-border: #e2e8f0;
    --color-border-light: #cbd5e1;

    /* Semantic Colors */
    --color-success: #22c55e;
    --color-error: #ef4444;
    --color-warning: #f59e0b;
    --color-info: #3b82f6;

    /* Typography */
    --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --font-size-xs: 0.75rem;
    --font-size-sm: 0.875rem;
    --font-size-base: 1rem;
    --font-size-lg: 1.125rem;
    --font-size-xl: 1.25rem;
    --font-size-2xl: 1.5rem;
    --font-size-3xl: 2rem;

    /* Spacing */
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;

    /* Border Radius */
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    --radius-full: 9999px;

    /* Shadows */
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.07);
    --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.1);
    --shadow-glow: 0 0 20px rgba(37, 99, 235, 0.15);

    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-base: 250ms ease;
    --transition-slow: 350ms ease;
}

/* Dark Theme */
[data-theme="dark"] {
    --color-primary: #3b82f6;
    --color-primary-dark: #2563eb;
    --color-primary-light: #60a5fa;

    --color-secondary: #94a3b8;
    --color-secondary-light: #cbd5e1;

    --color-accent: #38bdf8;

    --color-bg: #0f172a;
    --color-bg-secondary: #1e293b;
    --color-bg-card: #1e293b;
    --color-bg-input: #1e293b;

    --color-text: #f1f5f9;
    --color-text-secondary: #cbd5e1;
    --color-text-muted: #64748b;

    --color-border: #334155;
    --color-border-light: #475569;

    --shadow-glow: 0 0 20px rgba(59, 130, 246, 0.2);
}

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

html {
    font-size: 16px;
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-family);
    font-size: var(--font-size-base);
    line-height: 1.6;
    color: var(--color-text);
    background: var(--color-bg);
    min-height: 100vh;
    overflow: hidden;
    transition: background-color var(--transition-base), color var(--transition-base);
}

/* App Container */
.app-container {
    display: flex;
    flex-direction: column;
    height: 100vh;
    max-height: 100vh;
    overflow: hidden;
}

/* Header */
.header {
    background: var(--color-bg);
    border-bottom: 1px solid var(--color-border);
    padding: var(--spacing-md) var(--spacing-xl);
    flex-shrink: 0;
}

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    max-width: 1200px;
    margin: 0 auto;
}

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

.logo-icon {
    font-size: 32px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-right: var(--spacing-sm);
    /* Remove background for emoji leaf */
    background: transparent;
    color: inherit;
    width: auto;
    height: auto;
}

.logo-text {
    font-size: var(--font-size-lg);
    font-weight: 600;
    color: var(--color-text);
}

.header-actions {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-sm) var(--spacing-md);
    font-size: var(--font-size-sm);
    font-weight: 500;
    border-radius: var(--radius-md);
    border: none;
    cursor: pointer;
    transition: all var(--transition-base);
}

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

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

/* Theme Toggle Button */
.theme-toggle {
    width: 40px;
    height: 40px;
    border-radius: var(--radius-md);
    border: 1px solid var(--color-border);
    background: var(--color-bg-input);
    color: var(--color-text-secondary);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all var(--transition-fast);
}

.theme-toggle:hover {
    background: var(--color-border);
    color: var(--color-text);
}

.theme-toggle svg {
    width: 20px;
    height: 20px;
}

.theme-toggle .icon-sun {
    display: block;
}

.theme-toggle .icon-moon {
    display: none;
}

[data-theme="dark"] .theme-toggle .icon-sun {
    display: none;
}

[data-theme="dark"] .theme-toggle .icon-moon {
    display: block;
}

/* Language Toggle */
.language-toggle {
    display: flex;
    background: var(--color-bg-input);
    border-radius: var(--radius-md);
    padding: 2px;
    border: 1px solid var(--color-border);
}

.lang-btn {
    padding: var(--spacing-xs) var(--spacing-sm);
    font-size: var(--font-size-sm);
    font-weight: 500;
    color: var(--color-text-secondary);
    background: transparent;
    border: none;
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: all var(--transition-fast);
}

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

.lang-btn:hover:not(.active) {
    color: var(--color-text);
}

/* Chat Container */
.chat-container {
    flex: 1;
    overflow-y: auto;
    padding: var(--spacing-xl);
    scroll-behavior: smooth;
    background: var(--color-bg-secondary);
}

/* Welcome Section */
.welcome-section {
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100%;
    animation: fadeIn var(--transition-slow);
}

.welcome-content {
    text-align: center;
    max-width: 600px;
}

.welcome-icon {
    width: 64px;
    height: 64px;
    margin: 0 auto var(--spacing-lg);
    background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-accent) 100%);
    border-radius: var(--radius-xl);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: var(--font-size-3xl);
    color: white;
}

.welcome-content h1 {
    font-size: var(--font-size-3xl);
    font-weight: 700;
    margin-bottom: var(--spacing-md);
    color: var(--color-text);
}

.welcome-content>p {
    color: var(--color-text-secondary);
    font-size: var(--font-size-lg);
    margin-bottom: var(--spacing-2xl);
}

.example-questions h3 {
    font-size: var(--font-size-sm);
    color: var(--color-text-muted);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-bottom: var(--spacing-md);
}

.example-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--spacing-md);
}

.example-btn {
    padding: var(--spacing-md);
    background: var(--color-bg-card);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    color: var(--color-text);
    font-size: var(--font-size-sm);
    text-align: left;
    cursor: pointer;
    transition: all var(--transition-base);
    box-shadow: var(--shadow-sm);
}

.example-btn:hover {
    background: var(--color-bg);
    border-color: var(--color-primary);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

/* Messages Container */
.messages-container {
    max-width: 800px;
    margin: 0 auto;
    display: flex;
    flex-direction: column;
    gap: var(--spacing-lg);
}

.messages-container.hidden {
    display: none;
}

/* Message Styles */
/* Message Styles */
.message {
    display: flex;
    flex-direction: column;
    gap: 4px;
    max-width: 80%;
    animation: slideIn var(--transition-base);
}

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

.message.assistant {
    align-self: flex-start;
    align-items: flex-start;
}

.message-label {
    font-size: var(--font-size-xs);
    font-weight: 600;
    color: var(--color-text-secondary);
    padding: 0 var(--spacing-xs);
}

.message-content {
    max-width: 100%;
    padding: var(--spacing-md) var(--spacing-lg);
    border-radius: var(--radius-lg);
    line-height: 1.6;
    box-shadow: var(--shadow-sm);
}

.message.user .message-content {
    background: var(--color-primary);
    color: white;
    border-bottom-right-radius: var(--radius-sm);
}

.message.assistant .message-content {
    background: var(--color-bg-card);
    border: 1px solid var(--color-border);
    border-bottom-left-radius: var(--radius-sm);
}

.message-content p {
    margin-bottom: var(--spacing-sm);
}

.message-content p:last-child {
    margin-bottom: 0;
}

.message-content ul,
.message-content ol {
    margin: var(--spacing-sm) 0;
    padding-left: var(--spacing-lg);
}

.message-content li {
    margin-bottom: var(--spacing-xs);
}

.message-content a {
    color: var(--color-accent);
    text-decoration: none;
}

.message.user .message-content a {
    color: #bae6fd;
}

.message-content a:hover {
    text-decoration: underline;
}

/* Sources */
.message-sources {
    margin-top: var(--spacing-md);
    padding-top: var(--spacing-md);
    border-top: 1px solid var(--color-border);
}

.message-sources h4 {
    font-size: var(--font-size-xs);
    color: var(--color-text-muted);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-bottom: var(--spacing-sm);
}

.source-link {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-xs);
    font-size: var(--font-size-sm);
    color: var(--color-info);
    text-decoration: none;
    margin-right: var(--spacing-md);
    margin-bottom: var(--spacing-xs);
}

.source-link:hover {
    text-decoration: underline;
}

/* Loading Indicator */
.loading-indicator {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    max-width: 800px;
    margin: 0 auto;
    padding: var(--spacing-md);
}

.loading-indicator.hidden {
    display: none;
}

.loading-dots {
    display: flex;
    gap: 4px;
}

.loading-dots span {
    width: 8px;
    height: 8px;
    border-radius: var(--radius-full);
    background: var(--color-primary);
    animation: loadingDot 1.4s infinite ease-in-out both;
}

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

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

.loading-text {
    color: var(--color-text-secondary);
    font-size: var(--font-size-sm);
}

/* Input Area */
.input-area {
    background: var(--color-bg);
    border-top: 1px solid var(--color-border);
    padding: var(--spacing-lg) var(--spacing-xl);
    flex-shrink: 0;
}

.input-container {
    display: flex;
    gap: var(--spacing-md);
    max-width: 800px;
    margin: 0 auto;
    background: var(--color-bg-input);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-xl);
    padding: var(--spacing-sm) var(--spacing-md);
    transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

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

.input-container textarea {
    flex: 1;
    background: transparent;
    border: none;
    color: var(--color-text);
    font-size: var(--font-size-base);
    font-family: inherit;
    resize: none;
    outline: none;
    padding: var(--spacing-sm);
    max-height: 150px;
}

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

.send-btn {
    width: 40px;
    height: 40px;
    border-radius: var(--radius-full);
    border: none;
    background: var(--color-primary);
    color: white;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all var(--transition-fast);
    flex-shrink: 0;
}

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

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

.send-btn svg {
    width: 18px;
    height: 18px;
}

.input-footer {
    max-width: 800px;
    margin: var(--spacing-sm) auto 0;
    text-align: center;
}

.disclaimer {
    font-size: var(--font-size-xs);
    color: var(--color-text-muted);
}

.disclaimer a {
    color: var(--color-primary);
    text-decoration: none;
}

.disclaimer a:hover {
    text-decoration: underline;
}

.last-updated {
    display: inline-block;
    margin-top: var(--spacing-xs);
    color: var(--color-text-secondary);
    font-weight: 500;
}

/* Utilities */
.hidden {
    display: none !important;
}

/* Animations */
@keyframes fadeIn {
    from {
        opacity: 0;
    }

    to {
        opacity: 1;
    }
}

@keyframes slideIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes loadingDot {

    0%,
    80%,
    100% {
        transform: scale(0);
    }

    40% {
        transform: scale(1);
    }
}

/* Responsive */
@media (max-width: 768px) {
    .header {
        padding: var(--spacing-md);
    }

    .header-content {
        flex-wrap: wrap;
        gap: var(--spacing-sm);
    }

    .logo-text {
        font-size: var(--font-size-base);
    }

    .chat-container {
        padding: var(--spacing-md);
    }

    .welcome-content h1 {
        font-size: var(--font-size-2xl);
    }

    .example-grid {
        grid-template-columns: 1fr;
    }

    .message-content {
        max-width: 85%;
    }

    .input-area {
        padding: var(--spacing-md);
    }
}

/* Scrollbar */
::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: var(--color-bg-secondary);
}

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

::-webkit-scrollbar-thumb:hover {
    background: var(--color-border-light);
}