:root {
    --bg: #0f1117;
    --bg-panel: #171923;
    --bg-elevated: #1f2230;
    --border: #2a2e3d;
    --text: #e6e6eb;
    --text-dim: #9aa0ae;
    --accent: #6366f1;
    --accent-hover: #7678f0;
    --user-bubble: #2b2f42;
    --assistant-bubble: #171923;
    --danger: #ef4444;
}

* { box-sizing: border-box; }

body {
    margin: 0;
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: var(--bg);
    color: var(--text);
    height: 100vh;
    overflow: hidden;
}

/* Auth */
.auth-view {
    height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
}
.auth-card {
    background: var(--bg-panel);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 32px;
    width: 320px;
}
.auth-card h1 { margin: 0 0 4px; font-size: 22px; }
.auth-sub { color: var(--text-dim); font-size: 13px; margin: 0 0 20px; }
.auth-card form { display: flex; flex-direction: column; gap: 10px; }
.auth-card input {
    background: var(--bg-elevated);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 10px 12px;
    color: var(--text);
    font-size: 14px;
}
.auth-card button {
    background: var(--accent);
    border: none;
    border-radius: 8px;
    padding: 10px;
    color: white;
    font-weight: 600;
    cursor: pointer;
}
.auth-card button:hover { background: var(--accent-hover); }
.auth-toggle { text-align: center; margin-top: 14px; }
.auth-toggle a { color: var(--accent); font-size: 13px; text-decoration: none; }
.auth-error { color: var(--danger); font-size: 13px; text-align: center; min-height: 18px; }

/* App layout */
.app-view {
    display: flex;
    height: 100vh;
}
.sidebar {
    width: 260px;
    background: var(--bg-panel);
    border-right: 1px solid var(--border);
    display: flex;
    flex-direction: column;
    padding: 12px;
}
.new-chat-btn {
    background: var(--accent);
    color: white;
    border: none;
    border-radius: 8px;
    padding: 10px;
    font-weight: 600;
    cursor: pointer;
    margin-bottom: 10px;
}
.new-chat-btn:hover { background: var(--accent-hover); }
.conversation-list {
    flex: 1;
    overflow-y: auto;
    display: flex;
    flex-direction: column;
    gap: 4px;
}
.conv-item {
    padding: 9px 10px;
    border-radius: 6px;
    font-size: 13.5px;
    cursor: pointer;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    color: var(--text-dim);
}
.conv-item:hover { background: var(--bg-elevated); color: var(--text); }
.conv-item.active { background: var(--bg-elevated); color: var(--text); }
.sidebar-footer { display: flex; flex-direction: column; gap: 6px; padding-top: 10px; border-top: 1px solid var(--border); }
.ghost-btn {
    background: transparent;
    border: 1px solid var(--border);
    color: var(--text-dim);
    border-radius: 8px;
    padding: 8px;
    cursor: pointer;
    font-size: 13px;
}
.ghost-btn:hover { color: var(--text); border-color: var(--accent); }

.chat-main {
    flex: 1;
    display: flex;
    flex-direction: column;
}
.chat-header {
    padding: 12px 20px;
    border-bottom: 1px solid var(--border);
}
#model-select {
    background: var(--bg-elevated);
    color: var(--text);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 6px 10px;
    font-size: 13px;
}
.messages {
    flex: 1;
    overflow-y: auto;
    padding: 20px;
    display: flex;
    flex-direction: column;
    gap: 14px;
}
.msg {
    max-width: 720px;
    padding: 12px 16px;
    border-radius: 12px;
    line-height: 1.55;
    font-size: 14.5px;
}
.msg p:first-child { margin-top: 0; }
.msg p:last-child { margin-bottom: 0; }
.msg pre { background: #0b0d13; padding: 10px; border-radius: 8px; overflow-x: auto; }
.msg-user { align-self: flex-end; background: var(--user-bubble); }
.msg-assistant { align-self: flex-start; background: var(--assistant-bubble); border: 1px solid var(--border); }

.chat-form {
    display: flex;
    gap: 10px;
    padding: 16px 20px;
    border-top: 1px solid var(--border);
}
.chat-form textarea {
    flex: 1;
    resize: none;
    background: var(--bg-elevated);
    border: 1px solid var(--border);
    border-radius: 10px;
    color: var(--text);
    padding: 10px 14px;
    font-size: 14px;
    font-family: inherit;
    max-height: 160px;
}
.chat-form button {
    background: var(--accent);
    border: none;
    border-radius: 10px;
    padding: 0 20px;
    color: white;
    font-weight: 600;
    cursor: pointer;
}
.chat-form button:hover { background: var(--accent-hover); }

/* Modals */
.modal {
    position: fixed;
    inset: 0;
    background: rgba(0,0,0,0.55);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 100;
}
.modal-card {
    background: var(--bg-panel);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 24px;
    width: 420px;
    max-height: 80vh;
    overflow-y: auto;
}
.modal-card h2 { margin-top: 0; }
.modal-sub { color: var(--text-dim); font-size: 13px; }
.modal-card form { display: flex; flex-direction: column; gap: 8px; margin-bottom: 14px; }
.modal-card input, .modal-card select {
    background: var(--bg-elevated);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 8px 10px;
    color: var(--text);
    font-size: 13.5px;
}
.modal-card button[type="submit"] {
    background: var(--accent);
    border: none;
    border-radius: 8px;
    padding: 9px;
    color: white;
    font-weight: 600;
    cursor: pointer;
}
.close-modal-btn {
    width: 100%;
    background: transparent;
    border: 1px solid var(--border);
    color: var(--text-dim);
    border-radius: 8px;
    padding: 9px;
    cursor: pointer;
}
.memory-row, .provider-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 8px 0;
    border-bottom: 1px solid var(--border);
    font-size: 13px;
}
.memory-row button {
    background: transparent;
    border: none;
    color: var(--danger);
    cursor: pointer;
    font-size: 14px;
}

@media (max-width: 720px) {
    .sidebar { position: fixed; z-index: 50; height: 100vh; transform: translateX(-100%); transition: transform .2s; }
    .sidebar.open { transform: translateX(0); }
}