:root {
    --primary: #4F46E5;
    --primary-dark: #4338CA;
    --secondary: #7C3AED;
    --bg-primary: #0F172A;
    --bg-secondary: #1E293B;
    --bg-tertiary: #334155;
    --text-primary: #F8FAFC;
    --text-secondary: #94A3B8;
    --text-muted: #64748B;
    --user-bubble: #4F46E5;
    --ai-bubble: #1E293B;
    --border: #334155;
    --success: #10B981;
    --error: #EF4444;
    --warning: #F59E0B;
    --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.3);
}

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

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

.app-container {
    display: flex;
    flex-direction: column;
    height: 100vh;
    max-width: 900px;
    margin: 0 auto;
    background: var(--bg-primary);
}

/* Header */
.header {
    background: var(--bg-secondary);
    border-bottom: 1px solid var(--border);
    padding: 1rem 1.5rem;
    position: sticky;
    top: 0;
    z-index: 100;
}

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.logo h1 {
    font-size: 1.25rem;
    font-weight: 600;
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.header-links {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.anycoder-link {
    font-size: 0.75rem;
    color: var(--text-muted);
    text-decoration: none;
    padding: 0.375rem 0.75rem;
    background: var(--bg-tertiary);
    border-radius: 9999px;
    transition: all 0.2s ease;
}

.anycoder-link:hover {
    color: var(--text-primary);
    background: var(--primary);
}

/* Status Bar */
.status-bar {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem 1.5rem;
    background: var(--bg-secondary);
    border-bottom: 1px solid var(--border);
    font-size: 0.75rem;
    color: var(--text-secondary);
}

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

.status-bar.searching .status-indicator {
    background: var(--warning);
}

.status-bar.error .status-indicator {
    background: var(--error);
}

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

/* Chat Container */
.chat-container {
    flex: 1;
    overflow-y: auto;
    padding: 1.5rem;
    scroll-behavior: smooth;
}

.chat-messages {
    display: flex;
    flex-direction: column;
    gap: 1.25rem;
}

/* Messages */
.message {
    display: flex;
    gap: 0.75rem;
    max-width: 85%;
    animation: fadeIn 0.3s ease;
}

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

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

.message-avatar {
    width: 36px;
    height: 36px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    background: var(--bg-tertiary);
}

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

.message-content {
    padding: 0.875rem 1rem;
    border-radius: 1rem;
    line-height: 1.5;
    box-shadow: var(--shadow);
}

.user-message .message-content {
    background: var(--user-bubble);
    border-bottom-right-radius: 0.25rem;
}

.ai-message .message-content {
    background: var(--ai-bubble);
    border-bottom-left-radius: 0.25rem;
}

.message-content p {
    margin-bottom: 0.5rem;
}

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

/* Example Queries */
.example-queries {
    margin-top: 0.75rem;
    padding-top: 0.75rem;
    border-top: 1px solid var(--border);
}

.example-queries p {
    font-size: 0.875rem;
    color: var(--text-secondary);
    margin-bottom: 0.5rem;
}

.example-queries ul {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 0.375rem;
}

.example-queries li {
    font-size: 0.8125rem;
    color: var(--primary);
    cursor: pointer;
    padding: 0.25rem 0;
    transition: color 0.2s;
}

.example-queries li:hover {
    color: var(--secondary);
    text-decoration: underline;
}

/* Answer Types */
.answer-section {
    margin: 0.75rem 0;
    padding: 0.75rem;
    background: var(--bg-primary);
    border-radius: 0.5rem;
    border-left: 3px solid var(--primary);
}

.answer-section.definition {
    border-left-color: var(--success);
}

.answer-section.abstract {
    border-left-color: var(--secondary);
}

.answer-section.answer {
    border-left-color: var(--warning);
}

.answer-section.related {
    border-left-color: #3B82F6;
}

.answer-section h4 {
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--text-muted);
    margin-bottom: 0.5rem;
}

.answer-section p {
    color: var(--text-primary);
    font-size: 0.9375rem;
}

.source-link {
    font-size: 0.75rem;
    color: var(--text-muted);
    margin-top: 0.5rem;
}

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

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

.related-topics {
    margin-top: 0.75rem;
}

.related-topics h4 {
    font-size: 0.75rem;
    color: var(--text-muted);
    margin-bottom: 0.5rem;
}

.topic-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.375rem;
}

.topic-tag {
    font-size: 0.75rem;
    padding: 0.25rem 0.625rem;
    background: var(--bg-tertiary);
    border-radius: 9999px;
    color: var(--text-secondary);
    cursor: pointer;
    transition: all 0.2s;
    border: none;
    font-family: inherit;
}

.topic-tag:hover {
    background: var(--primary);
    color: var(--text-primary);
}

/* Loading */
.loading-message .typing-indicator {
    display: flex;
    gap: 0.25rem;
    margin-bottom: 0.5rem;
}

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

.typing-indicator span:nth-child(1) { animation-delay: 0s; }
.typing-indicator span:nth-child(2) { animation-delay: 0.2s; }
.typing-indicator span:nth-child(3) { animation-delay: 0.4s; }

@keyframes bounce {
    0%, 80%, 100% { transform: translateY(0); }
    40% { transform: translateY(-6px); }
}

.loading-text {
    font-size: 0.8125rem;
    color: var(--text-muted);
}

/* Input Area */
.input-area {
    background: var(--bg-secondary);
    border-top: 1px solid var(--border);
    padding: 1rem 1.5rem;
}

.chat-form {
    margin-bottom: 0.5rem;
}

.input-wrapper {
    display: flex;
    gap: 0.75rem;
    background: var(--bg-primary);
    border: 1px solid var(--border);
    border-radius: 9999px;
    padding: 0.375rem 0.5rem;
    transition: border-color 0.2s, box-shadow 0.2s;
}

.input-wrapper:focus-within {
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.2);
}

.input-wrapper input {
    flex: 1;
    background: transparent;
    border: none;
    outline: none;
    padding: 0.625rem 1rem;
    font-size: 0.9375rem;
    color: var(--text-primary);
    font-family: inherit;
}

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

.input-wrapper button {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    border-radius: 50%;
    border: none;
    background: var(--primary);
    color: white;
    cursor: pointer;
    transition: background 0.2s, transform 0.1s;
}

.input-wrapper button:hover:not(:disabled) {
    background: var(--primary-dark);
}

.input-wrapper button:active:not(:disabled) {
    transform: scale(0.95);
}

.input-wrapper button:disabled {
    background: var(--bg-tertiary);
    cursor: not-allowed;
}

.api-info {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.375rem;
    font-size: 0.6875rem;
    color: var(--text-muted);
}

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

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

.chat-container::-webkit-scrollbar-thumb {
    background: var(--bg-tertiary);
    border-radius: 3px;
}

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

/* Responsive */
@media (max-width: 640px) {
    .header {
        padding: 0.75rem 1rem;
    }

    .logo h1 {
        font-size: 1.125rem;
    }

    .chat-container {
        padding: 1rem;
    }

    .message {
        max-width: 90%;
    }

    .input-area {
        padding: 0.75rem 1rem;
    }
}