:root {
    --bg: #0f1115;
    --sidebar-bg: #15181f;
    --panel-bg: #1a1d25;
    --border: #2a2e38;
    --text: #e8e9ec;
    --text-dim: #9aa0ac;
    --accent: #6d5efc;
    --accent-hover: #7f72ff;
    --user-bubble: #2a2d3a;
    --assistant-bubble: #1e222c;
}

* {
    box-sizing: border-box;
}

html, body {
    margin: 0;
    padding: 0;
    height: 100%;
    background: var(--bg);
    color: var(--text);
    font-family: "Segoe UI", -apple-system, BlinkMacSystemFont, Roboto, sans-serif;
}

.app-shell {
    display: flex;
    height: 100vh;
}

/* Sidebar */
.sidebar {
    width: 260px;
    background: var(--sidebar-bg);
    border-right: 1px solid var(--border);
    display: flex;
    flex-direction: column;
    padding: 16px;
}

.sidebar-header {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 4px 4px 16px 4px;
    font-weight: 600;
    font-size: 16px;
}

.brand-dot {
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background: var(--accent);
    display: inline-block;
}

.new-chat-btn, .new-chat-btn-large {
    width: 100%;
    padding: 10px 14px;
    background: var(--accent);
    color: white;
    border: none;
    border-radius: 8px;
    font-size: 14px;
    font-weight: 500;
    cursor: pointer;
    margin-bottom: 12px;
    transition: background 0.15s ease;
}

    .new-chat-btn:hover, .new-chat-btn-large:hover {
        background: var(--accent-hover);
    }

.new-chat-btn-large {
    width: auto;
    padding: 12px 24px;
    margin-top: 16px;
}

.conversation-list {
    flex: 1;
    overflow-y: auto;
    display: flex;
    flex-direction: column;
    gap: 2px;
}

.conversation-item {
    display: flex;
    align-items: center;
    justify-content: space-between;
    border-radius: 6px;
    padding: 2px 4px;
}

    .conversation-item:hover {
        background: var(--panel-bg);
    }

    .conversation-item.active {
        background: var(--panel-bg);
        border: 1px solid var(--border);
    }

.conversation-link {
    flex: 1;
    display: block;
    padding: 8px 6px;
    color: var(--text-dim);
    text-decoration: none;
    font-size: 13px;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.conversation-item.active .conversation-link {
    color: var(--text);
}

.delete-form {
    margin: 0;
}

.delete-btn {
    background: none;
    border: none;
    color: var(--text-dim);
    cursor: pointer;
    font-size: 16px;
    padding: 4px 8px;
}

    .delete-btn:hover {
        color: #ff6b6b;
    }

.sidebar-footer {
    border-top: 1px solid var(--border);
    padding-top: 12px;
    margin-top: 8px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 8px;
}

.sidebar-user {
    font-size: 12px;
    color: var(--text-dim);
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
    max-width: 140px;
}

.logout-btn {
    background: none;
    border: 1px solid var(--border);
    color: var(--text-dim);
    border-radius: 6px;
    padding: 4px 10px;
    font-size: 12px;
    cursor: pointer;
}

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

/* Message action buttons (Copy / Regenerate) */
.message-actions {
    display: flex;
    gap: 8px;
    margin-top: 8px;
}

.msg-action-btn {
    background: none;
    border: 1px solid var(--border);
    color: var(--text-dim);
    border-radius: 6px;
    padding: 3px 10px;
    font-size: 12px;
    cursor: pointer;
}

    .msg-action-btn:hover {
        color: var(--text);
        border-color: var(--accent);
    }

    .msg-action-btn:disabled {
        opacity: 0.5;
        cursor: not-allowed;
    }

/* Auth pages (login/register) */
.auth-shell {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 24px;
}

.auth-card {
    width: 100%;
    max-width: 360px;
    background: var(--sidebar-bg);
    border: 1px solid var(--border);
    border-radius: 14px;
    padding: 32px;
}

    .auth-card h1 {
        margin: 0 0 4px 0;
        font-size: 20px;
        text-align: center;
    }

.auth-subtitle {
    color: var(--text-dim);
    text-align: center;
    margin: 0 0 24px 0;
    font-size: 14px;
}

.auth-card label {
    display: block;
    font-size: 13px;
    color: var(--text-dim);
    margin: 14px 0 6px 0;
}

.auth-input {
    width: 100%;
    background: var(--panel-bg);
    border: 1px solid var(--border);
    border-radius: 8px;
    color: var(--text);
    padding: 10px 12px;
    font-size: 14px;
}

    .auth-input:focus {
        outline: none;
        border-color: var(--accent);
    }

.password-field {
    position: relative;
}

    .password-field .auth-input {
        padding-right: 42px;
    }

.toggle-password {
    position: absolute;
    right: 8px;
    top: 50%;
    transform: translateY(-50%);
    background: none;
    border: none;
    cursor: pointer;
    font-size: 15px;
    opacity: 0.6;
    padding: 4px;
    line-height: 1;
}

    .toggle-password:hover {
        opacity: 1;
    }

.auth-checkbox {
    display: flex !important;
    align-items: center;
    gap: 8px;
    font-size: 13px;
    margin-top: 14px !important;
}

.auth-submit {
    width: 100%;
    margin-top: 22px;
    padding: 11px;
    background: var(--accent);
    color: white;
    border: none;
    border-radius: 8px;
    font-weight: 500;
    cursor: pointer;
}

    .auth-submit:hover {
        background: var(--accent-hover);
    }

.auth-switch {
    text-align: center;
    font-size: 13px;
    color: var(--text-dim);
    margin-top: 20px;
}

    .auth-switch a {
        color: var(--accent-hover);
        text-decoration: none;
    }

.auth-errors {
    color: #ff6b6b;
    font-size: 13px;
    margin-bottom: 4px;
}

    .auth-errors ul {
        margin: 0;
        padding-left: 18px;
    }

/* Main chat area */
.chat-main {
    flex: 1;
    display: flex;
    flex-direction: column;
    height: 100vh;
}

.empty-state {
    margin: auto;
    text-align: center;
    color: var(--text-dim);
}

    .empty-state h1 {
        color: var(--text);
        margin-bottom: 4px;
    }

.chat-header {
    padding: 16px 24px;
    border-bottom: 1px solid var(--border);
}

    .chat-header h2 {
        margin: 0;
        font-size: 15px;
        font-weight: 500;
        color: var(--text-dim);
    }

.message-list {
    flex: 1;
    overflow-y: auto;
    padding: 24px;
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.message {
    max-width: 720px;
    padding: 12px 16px;
    border-radius: 12px;
    line-height: 1.5;
    word-wrap: break-word;
}

/* User messages are plain text, so preserve their line breaks/spacing as typed */
.message-user .message-content {
    white-space: pre-wrap;
}

/* Assistant messages are rendered Markdown -> real HTML, so style the elements */
.message-assistant .message-content p {
    margin: 0 0 10px 0;
}

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

.message-assistant .message-content ul,
.message-assistant .message-content ol {
    margin: 0 0 10px 0;
    padding-left: 22px;
}

.message-assistant .message-content li {
    margin-bottom: 4px;
}

.message-assistant .message-content strong {
    color: var(--text);
    font-weight: 700;
}

.message-assistant .message-content code {
    background: rgba(255, 255, 255, 0.08);
    padding: 2px 6px;
    border-radius: 4px;
    font-family: "Cascadia Code", Consolas, monospace;
    font-size: 0.9em;
}

.message-assistant .message-content pre {
    background: #12141a;
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 12px 14px;
    overflow-x: auto;
    margin: 0 0 10px 0;
}

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

.message-assistant .message-content a {
    color: var(--accent-hover);
}

.message-assistant .message-content blockquote {
    border-left: 3px solid var(--accent);
    margin: 0 0 10px 0;
    padding: 4px 0 4px 12px;
    color: var(--text-dim);
}

.message-assistant .message-content h1,
.message-assistant .message-content h2,
.message-assistant .message-content h3 {
    margin: 12px 0 8px 0;
    font-size: 1.05em;
}

    .message-assistant .message-content h1:first-child,
    .message-assistant .message-content h2:first-child,
    .message-assistant .message-content h3:first-child {
        margin-top: 0;
    }

.message-role {
    font-size: 12px;
    font-weight: 600;
    color: var(--text-dim);
    margin-bottom: 4px;
}

.message-user {
    align-self: flex-end;
    background: var(--user-bubble);
}

.message-assistant {
    align-self: flex-start;
    background: var(--assistant-bubble);
    border: 1px solid var(--border);
}

.chat-input-form {
    display: flex;
    gap: 8px;
    padding: 16px 24px 24px 24px;
    border-top: 1px solid var(--border);
}

#chat-input {
    flex: 1;
    resize: none;
    background: var(--panel-bg);
    border: 1px solid var(--border);
    border-radius: 10px;
    color: var(--text);
    padding: 12px 14px;
    font-size: 14px;
    font-family: inherit;
    max-height: 160px;
}

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

#send-btn {
    padding: 0 20px;
    background: var(--accent);
    color: white;
    border: none;
    border-radius: 10px;
    font-weight: 500;
    cursor: pointer;
}

    #send-btn:hover {
        background: var(--accent-hover);
    }

    #send-btn:disabled {
        opacity: 0.6;
        cursor: not-allowed;
    }