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

:root {
    --primary-color: #5865f2;
    --primary-hover: #4752c4;
    --bg-dark: #1a1a2e;
    --bg-darker: #16162a;
    --bg-sidebar: #1e1e3f;
    --bg-chat: #0f0f23;
    --text-primary: #ffffff;
    --text-secondary: #b9bbbe;
    --text-muted: #72767d;
    --border-color: #2d2d5a;
    --message-bg: #2a2a4a;
    --input-bg: #1e1e3f;
    --success-color: #43b581;
    --warning-color: #faa61a;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
    background: var(--bg-dark);
    color: var(--text-primary);
    height: 100vh;
    overflow: hidden;
}

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

/* Login Screen */
.login-screen {
    width: 100%;
    height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    background: linear-gradient(135deg, var(--bg-darker) 0%, var(--bg-dark) 100%);
}

.login-box {
    background: var(--bg-sidebar);
    padding: 3rem;
    border-radius: 16px;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.4);
    text-align: center;
    max-width: 400px;
    width: 90%;
}

.logo {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.75rem;
    margin-bottom: 0.5rem;
}

.logo-icon {
    font-size: 2.5rem;
}

.logo h1 {
    font-size: 1.75rem;
    font-weight: 700;
    color: var(--text-primary);
}

.tagline {
    color: var(--text-secondary);
    margin-bottom: 2rem;
}

.form-group {
    margin-bottom: 1.5rem;
    text-align: left;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    color: var(--text-secondary);
    font-size: 0.875rem;
    font-weight: 500;
}

.form-group input {
    width: 100%;
    padding: 0.875rem 1rem;
    border: 2px solid var(--border-color);
    border-radius: 8px;
    background: var(--input-bg);
    color: var(--text-primary);
    font-size: 1rem;
    transition: border-color 0.2s;
}

.form-group input:focus {
    outline: none;
    border-color: var(--primary-color);
}

.btn-primary {
    width: 100%;
    padding: 0.875rem 1.5rem;
    border: none;
    border-radius: 8px;
    background: var(--primary-color);
    color: var(--text-primary);
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: background 0.2s;
}

.btn-primary:hover {
    background: var(--primary-hover);
}

/* Chat App Layout */
.chat-app {
    display: flex;
    width: 100%;
    height: 100vh;
}

.hidden {
    display: none !important;
}

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

.sidebar-header {
    padding: 1rem 1.25rem;
    display: flex;
    align-items: center;
    gap: 0.75rem;
    border-bottom: 1px solid var(--border-color);
}

.sidebar-header .logo-icon {
    font-size: 1.5rem;
}

.logo-text {
    font-weight: 700;
    font-size: 1.1rem;
}

.user-info {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 1rem 1.25rem;
    background: var(--bg-darker);
}

.user-avatar {
    width: 36px;
    height: 36px;
    border-radius: 50%;
    background: var(--primary-color);
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    font-size: 0.875rem;
}

.user-info span {
    flex: 1;
    font-weight: 500;
}

.btn-icon {
    background: none;
    border: none;
    color: var(--text-muted);
    cursor: pointer;
    padding: 0.5rem;
    font-size: 1rem;
    transition: color 0.2s;
}

.btn-icon:hover {
    color: var(--text-primary);
}

.rooms-section {
    flex: 1;
    overflow-y: auto;
    padding: 1rem 0;
}

.rooms-section h3 {
    padding: 0.5rem 1.25rem;
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--text-muted);
}

.rooms-list {
    list-style: none;
}

.rooms-list li {
    padding: 0.625rem 1.25rem;
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 0.5rem;
    color: var(--text-secondary);
    transition: all 0.15s;
}

.rooms-list li:hover {
    background: rgba(255, 255, 255, 0.05);
    color: var(--text-primary);
}

.rooms-list li.active {
    background: rgba(88, 101, 242, 0.2);
    color: var(--text-primary);
}

.room-hash {
    color: var(--text-muted);
    font-weight: 500;
}

/* Main Chat Area */
.chat-main {
    flex: 1;
    display: flex;
    flex-direction: column;
    background: var(--bg-chat);
}

.chat-header {
    padding: 1rem 1.5rem;
    border-bottom: 1px solid var(--border-color);
    background: var(--bg-dark);
}

.room-info {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.room-icon {
    color: var(--text-muted);
    font-weight: 700;
    font-size: 1.25rem;
}

#current-room-name {
    font-weight: 700;
    font-size: 1.1rem;
}

.room-description {
    color: var(--text-muted);
    font-size: 0.875rem;
    margin-top: 0.25rem;
}

.messages-container {
    flex: 1;
    overflow-y: auto;
    padding: 1rem;
}

.messages-list {
    display: flex;
    flex-direction: column;
    gap: 0.25rem;
}

/* Message Styles */
.message {
    display: flex;
    gap: 1rem;
    padding: 0.5rem 1rem;
    border-radius: 4px;
    transition: background 0.15s;
}

.message:hover {
    background: rgba(255, 255, 255, 0.02);
}

.message-avatar {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background: var(--primary-color);
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    flex-shrink: 0;
}

.message-content {
    flex: 1;
    min-width: 0;
}

.message-header {
    display: flex;
    align-items: baseline;
    gap: 0.5rem;
    margin-bottom: 0.25rem;
}

.message-username {
    font-weight: 600;
    color: var(--text-primary);
}

.message-timestamp {
    font-size: 0.75rem;
    color: var(--text-muted);
}

.message-text {
    color: var(--text-secondary);
    line-height: 1.4;
    word-wrap: break-word;
}

/* System Messages */
.message.system {
    justify-content: center;
    padding: 0.5rem;
}

.message.system .message-text {
    color: var(--text-muted);
    font-size: 0.875rem;
    font-style: italic;
}

/* Message Input */
.message-input-container {
    padding: 1rem 1.5rem;
    background: var(--bg-dark);
}

.message-form {
    display: flex;
    gap: 0.75rem;
    background: var(--input-bg);
    border-radius: 8px;
    padding: 0.25rem;
}

.message-form input {
    flex: 1;
    padding: 0.875rem 1rem;
    border: none;
    background: transparent;
    color: var(--text-primary);
    font-size: 1rem;
}

.message-form input:focus {
    outline: none;
}

.message-form input::placeholder {
    color: var(--text-muted);
}

.btn-send {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.75rem 1.25rem;
    border: none;
    border-radius: 6px;
    background: var(--primary-color);
    color: var(--text-primary);
    font-size: 0.875rem;
    font-weight: 600;
    cursor: pointer;
    transition: background 0.2s;
}

.btn-send:hover {
    background: var(--primary-hover);
}

.send-icon {
    font-size: 1rem;
}

/* Scrollbar Styling */
::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: var(--bg-darker);
}

::-webkit-scrollbar-thumb {
    background: var(--border-color);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--text-muted);
}

/* Responsive */
@media (max-width: 768px) {
    .sidebar {
        width: 200px;
    }
    
    .chat-header {
        padding: 0.75rem 1rem;
    }
}

@media (max-width: 576px) {
    .sidebar {
        display: none;
    }
}