:root {
    --bg-color: #ffffff;
    --fg-color: #000000;
    --panel-bg: #f0f0f0;
    --border-color: #ccc;
    --accent-color: #4285f4;
    --accent-text: #ffffff;
    --hover-bg: #e0e0e0;
}

body.dark-mode {
    --bg-color: #323232;
    --fg-color: #e6e6e6;
    --panel-bg: #3c3c3c;
    --border-color: #555;
    --hover-bg: #4c4c4c;
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
    font-family: 'Arial', sans-serif;
}

/* Login Screen Styles */
.login-overlay {
    position: fixed;
    top: 0; left: 0; right: 0; bottom: 0;
    background-color: rgba(0, 0, 0, 0.8);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 1000; /* Keeps it on top of everything */
}

.login-box {
    background-color: var(--panel-bg);
    padding: 30px;
    border-radius: 8px;
    box-shadow: 0 4px 15px rgba(0,0,0,0.3);
    text-align: center;
    width: 300px;
    display: flex;
    flex-direction: column;
    gap: 15px;
}

.login-box input {
    padding: 10px;
    border: 1px solid var(--border-color);
    border-radius: 4px;
    background-color: var(--bg-color);
    color: var(--fg-color);
}

.login-box button {
    background-color: var(--accent-color);
    color: var(--accent-text);
    font-weight: bold;
    padding: 10px;
}

.error-text {
    color: #ff5555;
    font-size: 0.9rem;
}

body {
    background-color: var(--bg-color);
    color: var(--fg-color);
    height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    transition: background-color 0.3s, color 0.3s;
}

.app-container {
    width: 100%;
    max-width: 1200px;
    height: 90vh;
    border: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
    background-color: var(--bg-color);
}

.top-bar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 10px 20px;
    border-bottom: 1px solid var(--border-color);
    background-color: var(--panel-bg);
}

button {
    cursor: pointer;
    border: none;
    padding: 8px 12px;
    border-radius: 4px;
    background-color: var(--panel-bg);
    color: var(--fg-color);
    border: 1px solid var(--border-color);
    transition: background 0.2s;
}

button:hover { background-color: var(--hover-bg); }

.main-content {
    display: flex;
    flex: 1;
    overflow: hidden;
}

.sidebar {
    width: 280px;
    border-right: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
    background-color: var(--panel-bg);
}

.sidebar-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 10px;
    border-bottom: 1px solid var(--border-color);
}

.chat-list {
    list-style: none;
    overflow-y: auto;
    flex: 1;
}

.chat-list li {
    padding: 15px;
    border-bottom: 1px solid var(--border-color);
    cursor: pointer;
    transition: background 0.2s;
}

.chat-list li:hover { background-color: var(--hover-bg); }

.chat-list li.active {
    background-color: var(--accent-color);
    color: var(--accent-text);
}

.chat-area {
    flex: 1;
    display: flex;
    flex-direction: column;
    position: relative;
}

.chat-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 15px 20px;
    border-bottom: 1px solid var(--border-color);
    background-color: var(--panel-bg);
}

.contact-info {
    display: flex;
    align-items: center;
    gap: 15px;
}

.contact-avatar {
    width: 50px;
    height: 50px;
    background-color: var(--accent-color);
    border-radius: 5px;
}

.messages-display {
    flex: 1;
    padding: 20px;
    overflow-y: auto;
    display: flex;
    flex-direction: column;
    gap: 10px;
    background-color: var(--bg-color);
}

.message {
    padding: 10px;
    border-radius: 5px;
    background-color: var(--panel-bg);
    align-self: flex-start;
    max-width: 70%;
    word-wrap: break-word;
}

.input-bar {
    display: flex;
    gap: 10px;
    padding: 15px;
    border-top: 1px solid var(--border-color);
    background-color: var(--panel-bg);
}

#messageInput {
    flex: 1;
    padding: 10px;
    border: 1px solid var(--border-color);
    border-radius: 4px;
    background-color: var(--bg-color);
    color: var(--fg-color);
}

#sendBtn {
    background-color: var(--accent-color);
    color: var(--accent-text);
    font-weight: bold;
    border: none;
}

#sendBtn:hover {
    opacity: 0.9;
}

.no-chat-selected {
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100%;
    color: gray;
    font-size: 1.2rem;
}

/* Authentication Screen Styles */
.auth-overlay {
    position: fixed;
    top: 0; left: 0; right: 0; bottom: 0;
    background-color: rgba(0, 0, 0, 0.8);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 1000;
}

.auth-box {
    background-color: var(--panel-bg);
    padding: 30px;
    border-radius: 8px;
    box-shadow: 0 4px 15px rgba(0,0,0,0.3);
    text-align: center;
    width: 320px;
}

.auth-box div[id$="View"] { /* Targets all our views */
    display: flex;
    flex-direction: column;
    gap: 15px;
}

.auth-buttons {
    display: flex;
    flex-direction: column;
    gap: 10px;
    margin-top: 10px;
}

.auth-box input {
    padding: 12px;
    border: 1px solid var(--border-color);
    border-radius: 4px;
    background-color: var(--bg-color);
    color: var(--fg-color);
    width: 100%;
}

.auth-box button {
    background-color: var(--accent-color);
    color: var(--accent-text);
    font-weight: bold;
    padding: 12px;
    width: 100%;
}

.auth-box button.secondary-btn {
    background-color: transparent;
    border: 1px solid var(--accent-color);
    color: var(--accent-color);
}

.auth-box button.text-btn {
    background-color: transparent;
    color: gray;
    font-weight: normal;
    padding: 5px;
    border: none;
}

.auth-box button.text-btn:hover {
    text-decoration: underline;
}

/* Password Visibility Toggle */
.password-wrapper {
    position: relative;
    display: flex;
    align-items: center;
}

.toggle-password-btn {
    position: absolute;
    right: 5px;
    background: none !important;
    border: none !important;
    color: gray !important;
    width: auto !important;
    padding: 5px !important;
    font-size: 1.2rem;
}

.error-text {
    color: #ff5555;
    font-size: 0.9rem;
    margin: 0;
}