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

/* ---------- Themes ---------- */
:root {
    /* dynamic (set from JS) */
    --chat-font-size: 16px;
    --chat-line-height: 1.6;
    --chat-font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    --user-bg: #3730a3;
    --assistant-bg: #1e293b;
}

/* Dark theme (default) */
:root,
:root[data-theme="dark"] {
    --bg-primary: #0f0f23;
    --bg-secondary: #1a1a2e;
    --bg-tertiary: #16213e;
    --text-primary: #e4e4e7;
    --text-secondary: #a1a1aa;
    --text-on-bubble: #ffffff;
    --accent: #6366f1;
    --accent-hover: #4f46e5;
    --border: #27272a;
    --danger: #ef4444;
    --code-bg: #0b0b18;
}

/* Light theme */
:root[data-theme="light"] {
    --bg-primary: #f5f6fa;
    --bg-secondary: #ffffff;
    --bg-tertiary: #eef0f6;
    --text-primary: #1f2333;
    --text-secondary: #6b7280;
    --text-on-bubble: #ffffff;
    --accent: #6366f1;
    --accent-hover: #4f46e5;
    --border: #e2e5ee;
    --danger: #dc2626;
    --code-bg: #f0f1f6;
}

body {
    font-family: var(--chat-font-family);
    background: var(--bg-primary);
    color: var(--text-primary);
    height: 100vh;
    overflow: hidden;
    transition: background 0.25s, color 0.25s;
}

.app {
    display: flex;
    flex-direction: column;
    height: 100vh;
    max-width: 1200px;
    margin: 0 auto;
}

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

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 0.75rem;
    flex-wrap: wrap;
}

.header h1 {
    font-size: 1.5rem;
    font-weight: 600;
}

.header-controls {
    display: flex;
    gap: 0.75rem;
    align-items: center;
    flex-wrap: wrap;
}

.model-select,
.setting-select {
    background: var(--bg-tertiary);
    color: var(--text-primary);
    border: 1px solid var(--border);
    padding: 0.5rem 1rem;
    border-radius: 0.5rem;
    font-size: 0.875rem;
    cursor: pointer;
    transition: border-color 0.2s;
}

.model-select:hover,
.setting-select:hover {
    border-color: var(--accent);
}

.search-toggle {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    cursor: pointer;
    background: var(--bg-tertiary);
    padding: 0.5rem 1rem;
    border-radius: 0.5rem;
    border: 1px solid var(--border);
    font-size: 0.875rem;
    transition: border-color 0.2s;
    user-select: none;
}

.search-toggle:hover { border-color: var(--accent); }
.search-toggle input[type="checkbox"] { margin: 0; cursor: pointer; accent-color: var(--accent); }
.search-toggle span { color: var(--text-primary); }

.icon-btn {
    background: var(--bg-tertiary);
    border: 1px solid var(--border);
    color: var(--text-primary);
    width: 2.5rem;
    height: 2.5rem;
    border-radius: 0.5rem;
    cursor: pointer;
    font-size: 1.25rem;
    transition: all 0.2s;
}

.icon-btn:hover {
    background: var(--accent);
    border-color: var(--accent);
    color: #fff;
}

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

.welcome-message {
    text-align: center;
    padding: 3rem 1rem;
    color: var(--text-secondary);
}

.welcome-message h2 { color: var(--text-primary); margin-bottom: 0.5rem; }
.context-info { margin-top: 1rem; font-size: 0.875rem; color: var(--accent); }

/* Message bubbles (no avatars) */
.message {
    margin-bottom: 1rem;
    display: flex;
    animation: fadeIn 0.3s ease-in;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(8px); }
    to { opacity: 1; transform: translateY(0); }
}

.message.user { justify-content: flex-end; }
.message.assistant { justify-content: flex-start; }

.message-bubble {
    display: flex;
    flex-direction: column;
    max-width: 78%;
}

.message.user .message-bubble { align-items: flex-end; }
.message.assistant .message-bubble { align-items: flex-start; }

.message-content {
    padding: 0.85rem 1.1rem;
    border-radius: 1.1rem;
    font-size: var(--chat-font-size);
    line-height: var(--chat-line-height);
    word-wrap: break-word;
    overflow-wrap: anywhere;
}

.message.user .message-content {
    background: var(--user-bg);
    color: var(--text-on-bubble);
    border-bottom-right-radius: 0.35rem;
}

.message.assistant .message-content {
    background: var(--assistant-bg);
    color: var(--text-on-bubble);
    border-bottom-left-radius: 0.35rem;
}

.message-meta {
    font-size: 0.7rem;
    opacity: 0.7;
    margin-top: 0.5rem;
}

/* Per-message action buttons */
.message-actions {
    display: flex;
    gap: 0.35rem;
    margin-top: 0.3rem;
    opacity: 0.45;
    transition: opacity 0.2s;
}

.message-bubble:hover .message-actions { opacity: 1; }

.msg-action-btn {
    background: var(--bg-tertiary);
    border: 1px solid var(--border);
    color: var(--text-primary);
    width: 1.9rem;
    height: 1.9rem;
    border-radius: 0.45rem;
    font-size: 0.85rem;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    line-height: 1;
    transition: all 0.15s;
}

.msg-action-btn:hover { border-color: var(--accent); transform: translateY(-1px); }

.typing-indicator {
    display: flex;
    gap: 0.25rem;
    padding: 0.35rem 0;
}

.typing-indicator span {
    width: 0.5rem;
    height: 0.5rem;
    background: currentColor;
    border-radius: 50%;
    opacity: 0.8;
    animation: bounce 1.4s infinite ease-in-out;
}

.typing-indicator span:nth-child(1) { animation-delay: -0.32s; }
.typing-indicator span:nth-child(2) { animation-delay: -0.16s; }

@keyframes bounce {
    0%, 80%, 100% { transform: scale(0); }
    40% { transform: scale(1); }
}

/* Code blocks */
.message-content pre {
    background: var(--code-bg);
    border-radius: 0.5rem;
    padding: 0.85rem;
    overflow-x: auto;
    margin: 0.5rem 0;
}

.message-content code {
    background: rgba(0,0,0,0.25);
    padding: 0.125rem 0.375rem;
    border-radius: 0.25rem;
    font-size: 0.9em;
    font-family: 'SF Mono', 'Consolas', monospace;
}

.message-content pre code { background: none; padding: 0; }

/* ---------- Input ---------- */
.input-area {
    background: var(--bg-secondary);
    border-top: 1px solid var(--border);
    padding: 1rem;
    flex-shrink: 0;
}

.input-container {
    display: flex;
    gap: 0.75rem;
    margin-bottom: 0.75rem;
}

#messageInput {
    flex: 1;
    background: var(--bg-tertiary);
    color: var(--text-primary);
    border: 1px solid var(--border);
    padding: 0.75rem;
    border-radius: 0.75rem;
    font-size: var(--chat-font-size);
    font-family: var(--chat-font-family);
    resize: none;
    max-height: 150px;
    transition: border-color 0.2s;
}

#messageInput:focus { outline: none; border-color: var(--accent); }

.send-btn, .stop-btn {
    width: 3rem;
    height: 3rem;
    background: var(--accent);
    color: white;
    border: none;
    border-radius: 0.75rem;
    cursor: pointer;
    transition: all 0.2s;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.send-btn:hover { background: var(--accent-hover); transform: scale(1.05); }
.send-btn:disabled { opacity: 0.5; cursor: not-allowed; transform: none; }
.stop-btn { background: var(--danger); }

.clear-btn {
    width: 100%;
    background: transparent;
    color: var(--text-secondary);
    border: 1px solid var(--border);
    padding: 0.5rem;
    border-radius: 0.5rem;
    cursor: pointer;
    font-size: 0.875rem;
    transition: all 0.2s;
}

.clear-btn:hover { color: var(--text-primary); border-color: var(--accent); }

/* Attachments */
.attachments-preview {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-bottom: 0.5rem;
}

.attachments-preview:empty { display: none; }

.attachment-item {
    position: relative;
    display: flex;
    align-items: center;
    gap: 0.4rem;
    background: var(--bg-tertiary);
    border: 1px solid var(--border);
    border-radius: 0.5rem;
    padding: 0.35rem 0.6rem;
    font-size: 0.8rem;
    color: var(--text-primary);
}

.attachment-item img,
.attachment-item video {
    width: 40px;
    height: 40px;
    object-fit: cover;
    border-radius: 0.3rem;
}

.attachment-item .att-icon { font-size: 1.3rem; }

.attachment-item .att-name {
    max-width: 120px;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.attachment-item .att-remove {
    background: none;
    border: none;
    color: var(--text-secondary);
    cursor: pointer;
    font-size: 1rem;
    padding: 0 0.2rem;
    line-height: 1;
}
.attachment-item .att-remove:hover { color: var(--danger); }

.attach-btn {
    background: var(--bg-tertiary);
    border: 1px solid var(--border);
    color: var(--text-primary);
    width: 3rem;
    height: 3rem;
    border-radius: 0.75rem;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    transition: all 0.2s;
}
.attach-btn:hover { border-color: var(--accent); color: var(--accent); }

.input-footer {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 1rem;
}

.media-hint {
    font-size: 0.75rem;
    color: var(--text-secondary);
}

/* Message media preview */
.msg-media {
    margin: 0.5rem 0;
    max-width: 100%;
}
.msg-media img,
.msg-media video {
    max-width: 100%;
    max-height: 300px;
    border-radius: 0.5rem;
}
.msg-media audio { width: 100%; }

/* ---------- Modal ---------- */
.modal {
    display: none;
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.6);
    z-index: 1000;
    align-items: center;
    justify-content: center;
    padding: 1rem;
}

.modal.active { display: flex; }

.modal-content {
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: 1rem;
    width: 100%;
    max-width: 520px;
    max-height: 90vh;
    overflow: auto;
}

.modal-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1.25rem 1.5rem;
    border-bottom: 1px solid var(--border);
    position: sticky;
    top: 0;
    background: var(--bg-secondary);
}

.close-btn {
    background: none;
    border: none;
    color: var(--text-primary);
    font-size: 2rem;
    cursor: pointer;
    line-height: 1;
}

.modal-body { padding: 1.5rem; }

.settings-section {
    margin-bottom: 1.75rem;
    padding-bottom: 1.5rem;
    border-bottom: 1px solid var(--border);
}
.settings-section:last-child { border-bottom: none; margin-bottom: 0; padding-bottom: 0; }

.settings-section h3 {
    font-size: 0.8rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--text-secondary);
    margin-bottom: 1rem;
}

.form-group { margin-bottom: 1.25rem; }
.form-group:last-child { margin-bottom: 0; }

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    color: var(--text-primary);
    font-weight: 500;
    font-size: 0.9rem;
}

.form-group input[type="password"],
.form-group input[type="text"] {
    width: 100%;
    background: var(--bg-tertiary);
    color: var(--text-primary);
    border: 1px solid var(--border);
    padding: 0.75rem;
    border-radius: 0.5rem;
    font-size: 1rem;
}

.form-group input:focus { outline: none; border-color: var(--accent); }
.form-group small { display: block; margin-top: 0.5rem; color: var(--text-secondary); font-size: 0.8rem; }

.setting-select { width: 100%; }

/* Range sliders */
input[type="range"] {
    width: 100%;
    accent-color: var(--accent);
    cursor: pointer;
}

/* Theme switch */
.theme-switch { display: flex; gap: 0.5rem; }
.theme-option {
    flex: 1;
    background: var(--bg-tertiary);
    border: 1px solid var(--border);
    color: var(--text-primary);
    padding: 0.6rem;
    border-radius: 0.5rem;
    cursor: pointer;
    font-size: 0.9rem;
    transition: all 0.2s;
}
.theme-option:hover { border-color: var(--accent); }
.theme-option.active {
    background: var(--accent);
    border-color: var(--accent);
    color: #fff;
}

/* Color pickers */
.color-row { display: flex; gap: 1rem; }
.color-item { flex: 1; }
.color-item input[type="color"] {
    width: 100%;
    height: 42px;
    border: 1px solid var(--border);
    border-radius: 0.5rem;
    background: var(--bg-tertiary);
    cursor: pointer;
    padding: 3px;
}

/* Buttons */
.primary-btn, .danger-btn, .secondary-btn {
    width: 100%;
    padding: 0.75rem;
    border: none;
    border-radius: 0.5rem;
    font-size: 1rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s;
}

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

.secondary-btn {
    background: transparent;
    color: var(--text-secondary);
    border: 1px solid var(--border);
}
.secondary-btn:hover { color: var(--text-primary); border-color: var(--accent); }

.danger-btn { background: transparent; color: var(--danger); border: 1px solid var(--danger); }
.danger-btn:hover { background: var(--danger); color: white; }

/* ---------- Mobile ---------- */
@media (max-width: 768px) {
    .message-bubble { max-width: 88%; }
    .header h1 { font-size: 1.2rem; width: 100%; }
    .header-controls { width: 100%; }
    .model-select { flex: 1; font-size: 0.8rem; }
    .search-toggle { font-size: 0.8rem; padding: 0.5rem 0.7rem; }
    .color-row { flex-direction: column; }
    .message-actions { opacity: 0.85; }
    .msg-action-btn { width: 2.1rem; height: 2.1rem; }
}

/* Pull to refresh indicator */
.pull-indicator {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    text-align: center;
    padding: 12px;
    background: var(--accent);
    color: white;
    font-size: 0.875rem;
    font-weight: 500;
    transform: translateY(-100%);
    opacity: 0;
    transition: transform 0.2s, opacity 0.2s;
    z-index: 1001;
    pointer-events: none;
}

.pull-indicator.ready {
    background: #10b981;
}

.pull-indicator.loading {
    animation: pulse 0.5s infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.6; }
}