:root {
    --bg-color: #f8f9fa; --chat-bg: #ffffff; --user-bubble-bg: #e9ecef; --ai-bubble-bg: #ffffff;
    --text-color: #343a40; --border-color: #dee2e6; --font-family: 'Ubuntu Mono', monospace; --sidebar-bg: #fff;
    --link-color: var(--text-color);
}
* { margin: 0; padding: 0; box-sizing: border-box; -webkit-tap-highlight-color: transparent; }
html, body { height: 100dvh; font-family: var(--font-family); background-color: var(--bg-color); color: var(--text-color); overflow: hidden; }

.app-container { display: grid; grid-template-rows: auto 1fr auto; height: 100%; max-width: 800px; margin: 0 auto; background-color: var(--chat-bg); }
header {
    display: grid;
    grid-template-columns: 1fr auto 1fr;
    align-items: center;
    gap: 15px;
    padding: 10px 15px;
    border-bottom: 1px solid var(--border-color);
    z-index: 10;
}
#menu-btn {
    justify-self: start;
}
header h1 {
    font-size: 1.2rem;
    font-weight: 700;
    text-align: center;
}
.social-links {
    display: flex;
    gap: 15px;
    justify-self: end;
}

main { overflow-y: auto; display: flex; flex-direction: column; gap: 8px; padding: 15px; scroll-behavior: smooth; }
footer {
    display: flex; flex-direction: column; gap: 10px; padding: 15px; padding-bottom: calc(15px + env(keyboard-inset-height, 0px));
    background-color: var(--chat-bg); z-index: 10; transition: padding-bottom 0.2s ease-out;
}
#chat-form { display: flex; align-items: center; gap: 8px; padding: 4px 8px; border-radius: 30px; border: 1px solid var(--border-color); box-shadow: 0 4px 20px rgba(0,0,0,0.08); }
#sidebar, #overlay, #modal-overlay, .modal { position: fixed; transition: all 0.3s ease-in-out; }
#sidebar { top: 0; left: -280px; width: 280px; height: 100%; background-color: var(--sidebar-bg); border-right: 1px solid var(--border-color); z-index: 200; display: flex; flex-direction: column; }
#sidebar.open { left: 0; }
.sidebar-content { flex-grow: 1; display: flex; flex-direction: column; overflow: hidden; }
.history-container { flex-grow: 1; overflow-y: auto; padding: 15px; }
.sidebar-footer { padding: 15px; border-top: 1px solid var(--border-color); display: flex; justify-content: center; align-items: center; gap: 20px; }
.social-link svg { width: 26px; height: 26px; opacity: 1; transition: opacity 0.2s, transform 0.2s; }
.social-link:hover svg { opacity: 0.8; transform: scale(1.1); }
.social-link[title="TikTok"] svg { fill: #333; }

#overlay, #modal-overlay { top: 0; left: 0; width: 100%; height: 100%; background-color: rgba(0, 0, 0, 0.4); opacity: 0; pointer-events: none; }
#overlay.active { opacity: 1; pointer-events: auto; z-index: 100; }
#modal-overlay.active { opacity: 1; pointer-events: auto; z-index: 300; }
.modal { top: 50%; left: 50%; transform: translate(-50%, -50%) scale(0.95); background: var(--chat-bg); padding: 25px; border-radius: 12px; box-shadow: 0 5px 25px rgba(0,0,0,0.15); width: 90%; max-width: 320px; text-align: center; z-index: 400; opacity: 0; pointer-events: none; }
.modal.active { transform: translate(-50%, -50%) scale(1); opacity: 1; pointer-events: auto; }
.modal p { font-size: 1rem; margin-bottom: 20px; line-height: 1.5; }
.modal-buttons { display: flex; gap: 10px; }
.modal-button { flex: 1; padding: 10px; border: none; border-radius: 8px; font-size: 0.95rem; font-family: var(--font-family); cursor: pointer; transition: background-color 0.2s; }
.modal-button.primary { background-color: #dc3545; color: white; } .modal-button.primary:hover { background-color: #c82333; }
.modal-button.secondary { background-color: #e9ecef; } .modal-button.secondary:hover { background-color: #d3d9df; }

.sidebar-header { display: flex; justify-content: space-between; align-items: center; padding: 15px; border-bottom: 1px solid var(--border-color); }
#new-chat-btn { flex-grow: 1; display: flex; align-items: center; gap: 10px; padding: 10px; border: 1px solid var(--border-color); border-radius: 8px; background-color: transparent; font-family: var(--font-family); font-size: 1rem; cursor: pointer; transition: background-color 0.2s; }
#new-chat-btn:hover { background-color: #f1f3f5; }
.history-title { font-size: 0.9rem; color: #868e96; margin-bottom: 5px; }
#history-list { list-style: none; }
.history-item { display: flex; justify-content: space-between; align-items: center; padding: 10px; border-radius: 6px; cursor: pointer; border-bottom: 1px solid #f1f3f5; }
.history-item:hover { background-color: #f1f3f5; }
.history-item-title { white-space: nowrap; overflow: hidden; text-overflow: ellipsis; font-size: 0.95rem; flex-grow: 1; }

.icon-button { background: none; border: none; cursor: pointer; padding: 8px; border-radius: 50%; display: flex; align-items: center; justify-content: center; flex-shrink: 0; transition: all 0.2s; }
.icon-button:hover { background-color: #f1f3f5; }
.icon-button:active { transform: scale(0.85); }
.delete-history-btn { opacity: 0.6; padding: 4px; } .delete-history-btn:hover { opacity: 1; }
.regenerate-btn { opacity: 0.5; padding: 4px; } .regenerate-btn:hover { opacity: 1; }
.regenerate-btn.loading { animation: spin 1s linear infinite; }
@keyframes spin { 100% { transform: rotate(360deg); } }

@keyframes slideUpFadeIn { from { opacity: 0; transform: translateY(10px); } to { opacity: 1; transform: translateY(0); } }
.message-wrapper { display: flex; max-width: 85%; animation: slideUpFadeIn 0.3s ease-out forwards; gap: 8px; align-items: flex-end; }
.message-wrapper.user { align-self: flex-end; flex-direction: row-reverse; }
.message-wrapper.ai { align-self: flex-start; }
.bubble-container { display: flex; flex-direction: column; }
.chat-bubble { padding: 10px 14px; border-radius: 18px; font-size: 0.95rem; line-height: 1.5; word-wrap: break-word; }
.chat-bubble p:not(:last-child) { margin-bottom: 0.75em; }
.chat-bubble ol, .chat-bubble ul { padding-left: 20px; }
.ai .chat-bubble { background-color: var(--ai-bubble-bg); border: 1px solid var(--border-color); box-shadow: 0 1px 2px rgba(0,0,0,0.05); border-top-left-radius: 4px; }
.user .chat-bubble { background-color: var(--user-bubble-bg); border-top-right-radius: 4px; }
.timestamp { font-size: 0.75rem; color: #adb5bd; margin-top: 4px; }
.user .timestamp { align-self: flex-end; } .ai .timestamp { align-self: flex-start; }
.chat-image { max-width: 100%; border-radius: 10px; margin-bottom: 8px; }

blockquote { margin: 1em 0; padding: 0; border: 1px solid var(--border-color); background-color: var(--chat-bg); border-radius: 8px; font-size: 0.9rem; overflow: hidden; box-shadow: 0 2px 8px rgba(0,0,0,0.06); }
blockquote a { display: block; padding: 12px 15px; color: var(--text-color); text-decoration: none; transition: background-color 0.2s; position: relative; }
blockquote a::after { content: '→'; display: inline-block; transition: transform 0.2s ease-out; position: absolute; right: 15px; top: 50%; transform: translateY(-50%); color: #adb5bd; }
blockquote a:hover { background-color: #f8f9fa; }
blockquote a:hover::after { transform: translateY(-50%) translateX(3px); color: var(--link-color); }
blockquote p { margin: 0 !important; line-height: 1.4; }
blockquote strong { color: #212529; font-weight: 700; display: block; margin-bottom: 2px; }
blockquote p:nth-of-type(2) { font-size: 0.85rem; color: #6c757d; }
blockquote p:last-of-type { font-size: 0.85rem; color: var(--link-color); font-weight: bold; margin-top: 8px !important; max-width: 80%; text-overflow: ellipsis; white-space: nowrap; overflow: hidden; }

.thinking-indicator { display: flex; align-self: flex-start; animation: slideUpFadeIn 0.3s ease-out forwards; }
.thinking-indicator .chat-bubble { padding: 10px 14px; color: #6c757d; position: relative; overflow: hidden; }
.thinking-indicator .chat-bubble::after { content: ''; position: absolute; top: 0; left: -150%; width: 100%; height: 100%; background: linear-gradient(90deg, transparent, rgba(255,255,255,0.4), transparent); animation: shimmer 2s infinite ease-in-out; }
@keyframes shimmer { 100% { left: 150%; } }

#message-input { flex-grow: 1; border: none; background: transparent; padding: 8px; font-size: 0.95rem; font-family: var(--font-family); outline: none; }
#image-preview-container { display: none; position: relative; width: 60px; height: 60px; }
#preview-img { width: 100%; height: 100%; border-radius: 8px; object-fit: cover; border: 1px solid var(--border-color); }
#remove-image-btn { position: absolute; top: -8px; right: -8px; background: rgba(0,0,0,0.6); color: white; border: none; width: 20px; height: 20px; border-radius: 50%; cursor: pointer; display: flex; align-items: center; justify-content: center; font-size: 14px; line-height: 20px; }

#welcome-screen { display: flex; flex-direction: column; align-items: center; justify-content: center; text-align: center; margin: auto; padding: 20px; animation: slideUpFadeIn 0.5s ease-out; }
.profile-pic { width: 80px; height: 80px; border-radius: 50%; object-fit: cover; margin-bottom: 15px; box-shadow: 0 4px 15px rgba(0,0,0,0.1); }
#welcome-screen h2 { font-size: 1.2rem; margin-bottom: 8px; }
#welcome-screen p { font-size: 0.9rem; color: #6c757d; max-width: 400px; margin-bottom: 20px; }
.suggestion-chips { display: flex; flex-wrap: wrap; gap: 10px; justify-content: center; }
.chip { background: var(--bg-color); border: 1px solid var(--border-color); border-radius: 16px; padding: 8px 14px; font-family: var(--font-family); font-size: 0.85rem; cursor: pointer; transition: all 0.2s ease; }
.chip:hover { background-color: #e9ecef; border-color: #adb5bd; }