:root {
    --viber-purple: #7360f2;
    --viber-bg: #f4f4f7;
    --viber-sent: #e2dffc;
    --viber-received: #ffffff;
    --text-dark: #333333;
    --text-gray: #8e8e93;
    --border: #e1e1e6;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

body {
    background-color: var(--viber-bg);
    height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    color: var(--text-dark);
}

.viber-container {
    width: 100%;
    max-width: 500px;
    height: 100vh;
    background: white;
    display: flex;
    flex-direction: column;
    box-shadow: 0 0 20px rgba(0,0,0,0.05);
}

/* Header */
.header {
    background-color: var(--viber-purple);
    color: white;
    padding: 15px 20px;
    display: flex;
    align-items: center;
    gap: 15px;
}

.back-btn {
    font-size: 20px;
    cursor: pointer;
}

.user-info {
    flex: 1;
}

.user-info h2 {
    font-size: 18px;
    font-weight: 600;
}

.user-info p {
    font-size: 12px;
    opacity: 0.9;
}

.header-icons {
    display: flex;
    gap: 20px;
}

/* Chat Area */
.chat-area {
    flex: 1;
    background-image: url('https://www.transparenttextures.com/patterns/cubes.png');
    background-color: #e5e5f7;
    padding: 20px;
    overflow-y: auto;
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.msg {
    max-width: 80%;
    padding: 10px 15px;
    border-radius: 15px;
    font-size: 15px;
    position: relative;
    line-height: 1.4;
    box-shadow: 0 1px 2px rgba(0,0,0,0.1);
}

.msg.received {
    align-self: flex-start;
    background-color: var(--viber-received);
    border-bottom-left-radius: 2px;
}

.msg.sent {
    align-self: flex-end;
    background-color: var(--viber-sent);
    border-bottom-right-radius: 2px;
}

.msg-time {
    font-size: 10px;
    color: var(--text-gray);
    margin-top: 5px;
    text-align: right;
}

/* Input Area */
.input-area {
    padding: 10px 15px;
    background: white;
    border-top: 1px solid var(--border);
    display: flex;
    align-items: center;
    gap: 12px;
}

.input-area input {
    flex: 1;
    border: none;
    background: #f0f0f5;
    padding: 12px 18px;
    border-radius: 25px;
    outline: none;
    font-size: 15px;
}

.icon-btn {
    color: var(--viber-purple);
    font-size: 22px;
    cursor: pointer;
    transition: 0.2s;
}

.icon-btn:hover {
    transform: scale(1.1);
}

/* Scrollbar */
::-webkit-scrollbar {
    width: 4px;
}
::-webkit-scrollbar-thumb {
    background: #ccc;
    border-radius: 10px;
}