:root {
    --bg-main: #131314;
    --bg-sidebar: #1e1e20;
    --bg-card: #282a2d;
    --border-color: #3c4043;
    --text-main: #e3e3e3;
    --text-muted: #9aa0a6;
    --primary-color: #a8c7fa;
    --primary-hover: #c2e7ff;
    --chat-user-bg: #2b2c2f;
    --chat-ai-bg: transparent;
    --font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

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

body {
    font-family: var(--font-family);
    background-color: var(--bg-main);
    color: var(--text-main);
    height: 100vh;
    overflow: hidden;
}

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

/* --- SIDEBAR --- */
.sidebar {
    width: 260px;
    background-color: var(--bg-sidebar);
    border-right: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
    transition: all 0.3s ease;
    flex-shrink: 0;
}

.sidebar.collapsed {
    width: 0;
    overflow: hidden;
    border-right: none;
}

.sidebar-header {
    padding: 16px;
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 1.2rem;
    font-weight: 600;
    cursor: pointer;
    transition: opacity 0.2s;
}

.logo:hover {
    opacity: 0.8;
}

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

.new-chat-btn {
    background-color: var(--bg-card);
    color: var(--text-main);
    border: 1px solid var(--border-color);
    padding: 12px;
    border-radius: 24px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    font-weight: 500;
    transition: background 0.2s;
}

.new-chat-btn:hover {
    background-color: #333538;
}

.chat-history {
    flex: 1;
    overflow-y: auto;
    padding: 0 12px;
}

.history-section-title {
    font-size: 0.75rem;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    padding: 8px 12px;
}

.history-item {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 10px 12px;
    border-radius: 8px;
    cursor: pointer;
    font-size: 0.9rem;
    color: var(--text-main);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    margin-bottom: 4px;
}

.history-item:hover, .history-item.active {
    background-color: var(--bg-card);
}

.sidebar-footer {
    padding: 16px;
    border-top: 1px solid var(--border-color);
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.user-profile {
    display: flex;
    align-items: center;
    gap: 10px;
}

.avatar {
    width: 32px;
    height: 32px;
    background-color: #4f5b66;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: bold;
}

.user-info {
    display: flex;
    flex-direction: column;
}

.user-name { font-size: 0.85rem; font-weight: 500; }
.user-status { font-size: 0.75rem; color: #81c995; }

/* --- MAIN CHAT AREA --- */
.main-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    height: 100%;
    position: relative;
    background-color: var(--bg-main);
}

.top-navbar {
    height: 56px;
    border-bottom: 1px solid var(--border-color);
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 20px;
}

.icon-btn, .toggle-sidebar-btn {
    background: none;
    border: none;
    color: var(--text-main);
    font-size: 1.1rem;
    cursor: pointer;
    width: 40px;
    height: 40px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: background 0.2s;
}

.icon-btn:hover, .toggle-sidebar-btn:hover {
    background-color: var(--bg-card);
}

.model-badge {
    background-color: var(--bg-card);
    padding: 6px 14px;
    border-radius: 16px;
    font-size: 0.85rem;
    border: 1px solid var(--border-color);
    display: flex;
    align-items: center;
    gap: 6px;
}

/* --- MESSAGES AREA --- */
.chat-messages {
    flex: 1;
    overflow-y: auto;
    padding: 20px 0;
    display: flex;
    flex-direction: column;
}

.welcome-container {
    max-width: 600px;
    margin: auto;
    text-align: center;
    padding: 20px;
}

.welcome-icon {
    font-size: 3rem;
    color: var(--primary-color);
    margin-bottom: 16px;
}

.welcome-container h2 {
    font-weight: 500;
    margin-bottom: 8px;
}

.welcome-container p {
    color: var(--text-muted);
    margin-bottom: 32px;
}

.suggested-prompts {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 12px;
}

.prompt-card {
    background-color: var(--bg-card);
    border: 1px solid var(--border-color);
    padding: 16px;
    border-radius: 12px;
    text-align: left;
    cursor: pointer;
    transition: transform 0.2s, background 0.2s;
}

.prompt-card:hover {
    background-color: #333538;
    transform: translateY(-2px);
}

.prompt-card h4 {
    font-size: 0.9rem;
    margin-bottom: 4px;
    color: var(--text-main);
}

.prompt-card p {
    font-size: 0.8rem;
    color: var(--text-muted);
    margin: 0;
}

/* --- CHAT BUBBLES --- */
.message-row {
    display: flex;
    padding: 20px 24px;
    width: 100%;
    justify-content: center;
}

.message-row.user-row {
    background-color: var(--chat-user-bg);
}

.message-content {
    max-width: 720px;
    width: 100%;
    display: flex;
    gap: 16px;
}

.msg-avatar {
    width: 30px;
    height: 30px;
    border-radius: 4px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.9rem;
    flex-shrink: 0;
}

.user-row .msg-avatar { background-color: #5f6368; }
.ai-row .msg-avatar { background-color: #1a73e8; color: white; }

.msg-text {
    line-height: 1.6;
    font-size: 0.95rem;
    word-break: break-word;
}

/* --- INPUT CONTAINER --- */
.input-container {
    padding: 0 24px 24px 24px;
    display: flex;
    flex-direction: column;
    align-items: center;
    background: linear-gradient(transparent, var(--bg-main) 20%);
}

.input-wrapper {
    max-width: 720px;
    width: 100%;
    background-color: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 26px;
    display: flex;
    align-items: flex-end;
    padding: 10px 16px;
    gap: 12px;
}

.input-wrapper textarea {
    flex: 1;
    background: none;
    border: none;
    outline: none;
    color: var(--text-main);
    font-family: inherit;
    font-size: 1rem;
    resize: none;
    max-height: 200px;
    padding: 4px 0;
}

.input-actions {
    display: flex;
    gap: 8px;
    align-items: center;
}

.action-btn {
    background: none;
    border: none;
    color: var(--text-muted);
    cursor: pointer;
    font-size: 1.1rem;
    width: 36px;
    height: 36px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
}

.action-btn:hover { color: var(--text-main); background: #3c4043; }

.send-btn {
    background-color: var(--primary-color);
    color: #131314;
    border: none;
    width: 36px;
    height: 36px;
    border-radius: 50%;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: background 0.2s;
}

.send-btn:hover { background-color: var(--primary-hover); }

.input-footer-text {
    font-size: 0.75rem;
    color: var(--text-muted);
    margin-top: 8px;
}

/* --- DROPDOWNS & MEDIA OPTIONS --- */
.media-container {
    position: relative;
    display: inline-block;
}

.dropdown-menu {
    display: none;
    position: absolute;
    bottom: 50px;
    left: 0;
    background-color: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    width: 250px;
    box-shadow: 0 8px 24px rgba(0,0,0,0.5);
    z-index: 100;
    padding: 6px 0;
}

.dropdown-menu.show {
    display: block;
}

.dropdown-header {
    padding: 10px 16px;
    font-size: 0.75rem;
    text-transform: uppercase;
    color: var(--text-muted);
    letter-spacing: 0.5px;
    border-bottom: 1px solid var(--border-color);
}

.dropdown-item {
    padding: 10px 16px;
    font-size: 0.9rem;
    color: var(--text-main);
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 12px;
    transition: background 0.2s;
}

.dropdown-item:hover {
    background-color: #333538;
    color: var(--primary-color);
}

/* --- MODAL OVERLAYS (SETTINGS & NEW CHAT) --- */
.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background-color: rgba(0, 0, 0, 0.75);
    backdrop-filter: blur(4px);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 200;
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.2s ease;
}

.modal-overlay.show {
    opacity: 1;
    pointer-events: auto;
}

.modal-box {
    background-color: var(--bg-sidebar);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    width: 100%;
    max-width: 500px;
    box-shadow: 0 12px 36px rgba(0,0,0,0.6);
    overflow: hidden;
}

.modal-header {
    padding: 16px 20px;
    border-bottom: 1px solid var(--border-color);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.close-modal-btn {
    background: none;
    border: none;
    color: var(--text-muted);
    font-size: 1.5rem;
    cursor: pointer;
}
.close-modal-btn:hover { color: var(--text-main); }

.modal-body {
    padding: 20px;
}

.setting-label {
    display: block;
    font-size: 0.85rem;
    color: var(--text-muted);
    margin-bottom: 6px;
    margin-top: 14px;
}
.setting-label:first-of-type { margin-top: 0; }

.form-control {
    width: 100%;
    background-color: var(--bg-main);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 10px;
    color: var(--text-main);
    font-family: inherit;
    outline: none;
}

.form-range {
    width: 100%;
    margin: 10px 0;
}

.modal-footer {
    padding: 14px 20px;
    background-color: var(--bg-card);
    border-top: 1px solid var(--border-color);
    display: flex;
    justify-content: flex-end;
    gap: 12px;
}

.modal-btn {
    padding: 8px 16px;
    border-radius: 20px;
    border: none;
    cursor: pointer;
    font-weight: 500;
}
.primary-btn { background-color: var(--primary-color); color: #131314; }
.primary-btn:hover { background-color: var(--primary-hover); }
.secondary-btn { background-color: transparent; color: var(--text-main); border: 1px solid var(--border-color); }
.secondary-btn:hover { background-color: rgba(255,255,255,0.05); }

/* Persona Workspace Cards Layout */
.persona-grid {
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.persona-card {
    background-color: var(--bg-card);
    border: 1px solid var(--border-color);
    padding: 14px;
    border-radius: 10px;
    display: flex;
    align-items: center;
    gap: 16px;
    cursor: pointer;
    transition: background 0.2s;
}
.persona-card:hover {
    background-color: #333538;
    border-color: var(--primary-color);
}
.persona-card i {
    font-size: 1.4rem;
    color: var(--primary-color);
    width: 30px;
    text-align: center;
}
.persona-card div strong { font-size: 0.9rem; display: block; }
.persona-card div p { font-size: 0.75rem; color: var(--text-muted); margin: 0; }

/* Custom Scrollbar */
::-webkit-scrollbar { width: 8px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: var(--border-color); border-radius: 4px; }
::-webkit-scrollbar-thumb:hover { background: #5f6368; }