:root {
    --bg-app: #e1e1de;
    --bg-chat: #efeae2;
    --bg-panel: #ffffff;
    --header-bg: #f0f2f5;
    --border-color: #e9edef;
    --text-primary: #111b21;
    --text-secondary: #667781;
    --msg-in: #ffffff;
    --msg-out: #d9fdd3;
    --primary-color: #00a884;
    --hover-bg: #f5f6f6;
    --active-bg: #f0f2f5;
    --bubble-meta: #667781;
}

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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    background-color: var(--bg-app);
    height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    color: var(--text-primary);
}

.app-container {
    display: flex;
    width: 100%;
    max-width: 1600px;
    height: 100vh;
    background-color: var(--bg-panel);
    box-shadow: 0 1px 1px rgba(0,0,0,0.06), 0 2px 5px 0 rgba(0,0,0,0.06);
}

@media (min-width: 1440px) {
    .app-container {
        height: 95vh;
        border-radius: 12px;
        overflow: hidden;
    }
}

/* Sidebar */
.sidebar {
    width: 30%;
    min-width: 300px;
    max-width: 450px;
    border-right: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
    background-color: var(--bg-panel);
}

.sidebar-header, .chat-header {
    height: 60px;
    background-color: var(--header-bg);
    display: flex;
    align-items: center;
    padding: 10px 16px;
    justify-content: space-between;
}

.sidebar-header h2 {
    font-size: 16px;
    font-weight: 600;
}

.search-container {
    padding: 8px 12px;
    background-color: var(--bg-panel);
    border-bottom: 1px solid var(--border-color);
}

.search-bar {
    display: flex;
    align-items: center;
    background-color: var(--header-bg);
    border-radius: 8px;
    padding: 8px 12px;
}

.search-bar i {
    color: var(--text-secondary);
    font-size: 14px;
    margin-right: 12px;
}

.search-bar input {
    border: none;
    background: transparent;
    outline: none;
    width: 100%;
    font-size: 14px;
    color: var(--text-primary);
}

.conversation-list {
    flex: 1;
    overflow-y: auto;
}

.conversation-item {
    display: flex;
    align-items: center;
    padding: 12px 16px;
    cursor: pointer;
    transition: background-color 0.2s;
    border-bottom: 1px solid var(--border-color);
}

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

.conversation-item.active {
    background-color: var(--active-bg);
}

.avatar {
    width: 48px;
    height: 48px;
    border-radius: 50%;
    background-color: #dfe5e7;
    margin-right: 16px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 18px;
    font-weight: 600;
    color: #fff;
    flex-shrink: 0;
}

.conv-details {
    flex: 1;
    overflow: hidden;
}

.conv-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 4px;
}

.conv-id {
    font-weight: 500;
    font-size: 16px;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.conv-time {
    font-size: 12px;
    color: var(--text-secondary);
}

.conv-last-msg {
    font-size: 13px;
    color: var(--text-secondary);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

/* Chat Area */
.chat-area {
    flex: 1;
    display: flex;
    flex-direction: column;
    background-color: var(--bg-chat);
    position: relative;
    background-image: url('https://user-images.githubusercontent.com/15075759/28719144-86dc0f70-73b1-11e7-911d-60d70fcded21.png');
    background-repeat: repeat;
    background-size: 400px;
    opacity: 0.95;
}

.chat-header {
    justify-content: space-between;
    border-left: 1px solid var(--border-color);
    z-index: 10;
    position: absolute;
    top: 0;
    width: 100%;
}

.chat-header-info {
    display: flex;
    align-items: center;
}

.chat-header .avatar {
    width: 40px;
    height: 40px;
    margin-right: 12px;
}

.chat-title h3 {
    font-size: 16px;
    font-weight: 500;
}

.chat-status {
    font-size: 13px;
    color: var(--text-secondary);
}

.chat-messages {
    flex: 1;
    padding: 20px 8%;
    overflow-y: auto;
    display: flex;
    flex-direction: column;
    padding-top: 80px; /* para no solapar con header absolute */
}

.empty-state {
    display: flex;
    height: 100%;
    justify-content: center;
    align-items: center;
    text-align: center;
    background-color: var(--bg-panel);
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    z-index: 5;
}

.empty-state-content {
    color: var(--text-secondary);
}

.empty-state-content i {
    font-size: 80px;
    color: var(--border-color);
    margin-bottom: 24px;
}

.empty-state-content h2 {
    font-size: 32px;
    font-weight: 300;
    margin-bottom: 16px;
    color: #41525d;
}

.empty-state-content p {
    font-size: 14px;
    max-width: 400px;
    line-height: 1.5;
    margin: 0 auto;
}

/* Chat Bubbles */
.message-row {
    display: flex;
    margin-bottom: 12px;
    width: 100%;
}

.message-row.in {
    justify-content: flex-start;
}

.message-row.out {
    justify-content: flex-end;
}

.bubble {
    max-width: 65%;
    padding: 6px 7px 8px 9px;
    border-radius: 7.5px;
    position: relative;
    box-shadow: 0 1px 0.5px rgba(11,20,26,.13);
    font-size: 14.2px;
    line-height: 19px;
    color: #111b21;
}

.message-row.in .bubble {
    background-color: var(--msg-in);
    border-top-left-radius: 0;
}

.message-row.in .bubble::before {
    content: '';
    position: absolute;
    top: 0;
    left: -8px;
    width: 0;
    height: 0;
    border-top: 8px solid var(--msg-in);
    border-left: 8px solid transparent;
}

.message-row.out .bubble {
    background-color: var(--msg-out);
    border-top-right-radius: 0;
}

.message-row.out .bubble::before {
    content: '';
    position: absolute;
    top: 0;
    right: -8px;
    width: 0;
    height: 0;
    border-top: 8px solid var(--msg-out);
    border-right: 8px solid transparent;
}

.msg-text {
    margin-bottom: 2px;
    word-wrap: break-word;
    display: inline-block;
    padding-right: 40px; /* space for time/status */
}

.msg-meta {
    float: right;
    margin: -10px 0 -5px 4px;
    position: relative;
    bottom: -15px;
    font-size: 11px;
    color: var(--bubble-meta);
    display: flex;
    align-items: center;
}

.msg-time {
    margin-right: 4px;
}

.msg-status {
    color: #53bdeb; /* Blue checkmarks */
    font-size: 14px;
}

/* Custom Scrollbar */
::-webkit-scrollbar {
    width: 6px;
}

::-webkit-scrollbar-track {
    background: transparent;
}

::-webkit-scrollbar-thumb {
    background: rgba(17, 27, 33, 0.2);
    border-radius: 3px;
}

::-webkit-scrollbar-thumb:hover {
    background: rgba(17, 27, 33, 0.3);
}