:root {
    /* Light Theme (default) */
    --bg-primary: #ffffff;
    --bg-secondary: #f7f7f8;
    --bg-input: #ffffff;
    --text-primary: #202123;
    --text-secondary: #6e6e80;
    --text-user-message: #ffffff;
    /* Texto en burbuja de usuario */
    --border-color: #e5e5e5;
    --accent-color: #10a37f;
    /* Verde similar a ChatGPT */
    --accent-text-color: #ffffff;
    --message-user-bg: var(--accent-color);
    --message-other-bg: #f0f0f0;
    --icon-color: #6e6e80;
    --icon-hover-bg: #e0e0e0;
    --shadow-color: rgba(0, 0, 0, 0.05);
}

body.dark-mode {
    /* Dark Theme */
    --bg-primary: #202123;
    /* Fondo principal oscuro */
    --bg-secondary: #343541;
    /* Fondo de mensajes y área de input */
    --bg-input: #40414f;
    /* Fondo del input de texto */
    --text-primary: #ececf1;
    --text-secondary: #a9a9b3;
    --text-user-message: #ececf1;
    /* Texto en burbuja de usuario */
    --border-color: #565869;
    --accent-color: #10a37f;
    /* Mantenemos el acento, o podría cambiar */
    --accent-text-color: #ffffff;
    --message-user-bg: #2b574e;
    /* Un verde más oscuro para dark mode */
    --message-other-bg: #444654;
    --icon-color: #a9a9b3;
    --icon-hover-bg: #565869;
    --shadow-color: rgba(0, 0, 0, 0.2);
}

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

body {
    font-family: "Söhne", "Helvetica Neue", Helvetica, Arial, sans-serif;
    /* Similar a ChatGPT */
    background-color: var(--bg-primary);
    color: var(--text-primary);
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    transition: background-color 0.3s, color 0.3s;
}

#chat-app {
    background-color: var(--bg-secondary);
    width: 100%;
    max-width: 800px;
    /* Un poco más ancho */
    height: 90vh;
    max-height: 850px;
    border: 1px solid var(--border-color);
    border-radius: 12px;
    box-shadow: 0 8px 20px var(--shadow-color);
    display: flex;
    flex-direction: column;
    overflow: hidden;
    transition: background-color 0.3s, border-color 0.3s;
}

#chat-header {
    padding: 12px 20px;
    border-bottom: 1px solid var(--border-color);
    display: flex;
    justify-content: space-between;
    align-items: center;
    background-color: var(--bg-primary);
    /* Encabezado un poco diferente */
    transition: background-color 0.3s, border-color 0.3s;
}

#user-info-header {
    display: flex;
    align-items: center;
    gap: 10px;
}

#user-info-header input#who {
    padding: 8px 12px;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    font-size: 0.9rem;
    background-color: var(--bg-input);
    color: var(--text-primary);
    transition: background-color 0.3s, border-color 0.3s, color 0.3s;
}

#user-info-header input#who:disabled {
    background-color: transparent;
    border-color: transparent;
    font-weight: 500;
}

#user-info-header button {
    padding: 8px 10px;
    border: none;
    border-radius: 6px;
    background-color: var(--accent-color);
    color: var(--accent-text-color);
    cursor: pointer;
    font-size: 0.85rem;
    transition: opacity 0.2s, background-color 0.3s;
}

#user-info-header button:hover {
    opacity: 0.85;
}

#theme-toggle-btn {
    background: none;
    border: none;
    cursor: pointer;
    padding: 5px;
    color: var(--icon-color);
    transition: color 0.3s;
}

#theme-toggle-btn svg {
    width: 20px;
    height: 20px;
    fill: currentColor;
}


#messages-list {
    flex-grow: 1;
    overflow-y: auto;
    padding: 20px;
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.message-item {
    display: flex;
    flex-direction: column;
    max-width: 85%;
}

.message-item.user {
    align-self: flex-end;
}

.message-item.other {
    align-self: flex-start;
}

.message-sender {
    font-size: 0.8rem;
    font-weight: 500;
    color: var(--text-secondary);
    margin-bottom: 6px;
    transition: color 0.3s;
}

.message-item.user .message-sender {
    text-align: right;
}

.message-content-wrapper {
    padding: 12px 16px;
    border-radius: 8px;
    line-height: 1.5;
    font-size: 0.95rem;
    word-wrap: break-word;
    transition: background-color 0.3s, color 0.3s;
}

.message-item.user .message-content-wrapper {
    background-color: var(--message-user-bg);
    color: var(--text-user-message);
}

.message-item.other .message-content-wrapper {
    background-color: var(--message-other-bg);
    color: var(--text-primary);
}

.message-image-container {
    width: 220px;
    height: 160px;
    overflow: hidden;
    border-radius: 6px;
    margin-top: 5px;
    background-color: var(--message-other-bg);
    cursor: zoom-in;
    transition: background-color 0.3s;
}

.message-image-container img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
}

#message-input-area {
    padding: 15px 20px;
    border-top: 1px solid var(--border-color);
    background-color: var(--bg-primary);
    display: flex;
    flex-direction: column;
    gap: 8px;
    transition: background-color 0.3s, border-color 0.3s;
}

#input-actions {
    display: flex;
    gap: 8px;
}

.action-btn {
    background: none;
    border: 1px solid var(--border-color);
    color: var(--icon-color);
    cursor: pointer;
    padding: 8px;
    border-radius: 6px;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: background-color 0.2s, border-color 0.3s, color 0.3s;
}

.action-btn:hover {
    background-color: var(--icon-hover-bg);
}

.action-btn svg {
    width: 18px;
    height: 18px;
    fill: currentColor;
}

#message-form {
    display: flex;
    gap: 10px;
    align-items: center;
}

#message-form input#what {
    flex-grow: 1;
    padding: 12px 16px;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    font-size: 0.95rem;
    background-color: var(--bg-input);
    color: var(--text-primary);
    resize: none;
    transition: background-color 0.3s, border-color 0.3s, color 0.3s, box-shadow 0.2s;
}

#message-form input#what:focus {
    outline: none;
    border-color: var(--accent-color);
    box-shadow: 0 0 0 2px color-mix(in srgb, var(--accent-color) 20%, transparent);
}

#message-form input[type="submit"] {
    padding: 12px 18px;
    border: none;
    border-radius: 8px;
    background-color: var(--accent-color);
    color: var(--accent-text-color);
    font-weight: 500;
    font-size: 0.95rem;
    cursor: pointer;
    transition: opacity 0.2s, background-color 0.3s;
}

#message-form input[type="submit"]:hover {
    opacity: 0.85;
}

emoji-picker {
    position: absolute;
    bottom: 90px;
    right: 20px;
    z-index: 1000;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.15);
    border-radius: 8px;
    /* El tema se aplica vía JS con el atributo 'theme' */
}

#messages-list::-webkit-scrollbar {
    width: 8px;
}

#messages-list::-webkit-scrollbar-track {
    background: transparent;
}

#messages-list::-webkit-scrollbar-thumb {
    background-color: color-mix(in srgb, var(--text-secondary) 40%, transparent);
    border-radius: 10px;
}

#messages-list::-webkit-scrollbar-thumb:hover {
    background-color: color-mix(in srgb, var(--text-secondary) 60%, transparent);
}

#image-modal {
    display: none;
    position: fixed;
    z-index: 2000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    overflow: auto;
    background-color: rgba(0, 0, 0, 0.85);
    justify-content: center;
    align-items: center;
}

#image-modal img {
    max-width: 90%;
    max-height: 90%;
    display: block;
    margin: auto;
    border-radius: 4px;
    animation: zoomIn 0.3s ease-out;
}

@keyframes zoomIn {
    from {
        transform: scale(0.8);
        opacity: 0;
    }

    to {
        transform: scale(1);
        opacity: 1;
    }
}

#image-modal-close {
    position: absolute;
    top: 20px;
    right: 35px;
    color: #f1f1f1;
    font-size: 40px;
    font-weight: bold;
    cursor: pointer;
    transition: color 0.2s;
}

#image-modal-close:hover {
    color: #bbb;
}

@media (max-width: 700px) {
    body {
        padding: 0;
    }

    #chat-app {
        height: 100vh;
        max-height: 100vh;
        border-radius: 0;
        border-left: 0;
        border-right: 0;
    }

    #messages-list {
        gap: 15px;
        padding: 15px;
    }

    .message-item {
        max-width: 90%;
    }

    #chat-header,
    #message-input-area {
        padding: 10px 15px;
    }

    emoji-picker {
        bottom: 80px;
        right: 15px;
    }
}