:root {
    --bg-color: #0f172a;
    --card-bg: rgba(30, 41, 59, 0.7);
    --accent-color: #38bdf8;
    --accent-hover: #0ea5e9;
    --text-primary: #f8fafc;
    --text-secondary: #94a3b8;
    --error-color: #ef4444;
    --glass-border: rgba(255, 255, 255, 0.1);
    --msg-sent: #0369a1;
    --msg-received: #334155;
}

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

body {
    background-color: var(--bg-color);
    color: var(--text-primary);
    height: 100vh;
    overflow: hidden;
    background-image: radial-gradient(circle at top right, #1e293b, transparent), radial-gradient(circle at bottom left, #0f172a, transparent);
}

#app {
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
}

.screen {
    display: none;
    width: 100%;
    height: 100%;
    opacity: 0;
    transition: opacity 0.3s ease;
}

.screen.active {
    display: flex;
    opacity: 1;
}

/* Login Screen */
#login-screen {
    align-items: center;
    justify-content: center;
}

.glass-card {
    background: var(--card-bg);
    backdrop-filter: blur(12px);
    border: 1px solid var(--glass-border);
    padding: 2.5rem;
    border-radius: 1.5rem;
    width: 100%;
    max-width: 450px;
    box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.5);
}

h1 {
    font-size: 1.875rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
    text-align: center;
}

p {
    color: var(--text-secondary);
    text-align: center;
    margin-bottom: 2rem;
}

.input-group {
    margin-bottom: 1.5rem;
}

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

input,
textarea {
    width: 100%;
    background: rgba(15, 23, 42, 0.6);
    border: 1px solid var(--glass-border);
    border-radius: 0.75rem;
    padding: 0.75rem 1rem;
    color: var(--text-primary);
    font-size: 1rem;
    transition: border-color 0.2s;
}

input:focus,
textarea:focus {
    outline: none;
    border-color: var(--accent-color);
}

button {
    width: 100%;
    background-color: var(--accent-color);
    color: white;
    border: none;
    border-radius: 0.75rem;
    padding: 0.875rem;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition:
        background-color 0.2s,
        transform 0.1s;
}

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

button:active {
    transform: scale(0.98);
}

.error-msg {
    color: var(--error-color);
    font-size: 0.875rem;
    margin-top: 1rem;
    text-align: center;
}

/* Chat Screen */
.chat-container {
    display: flex;
    width: 100%;
    height: 100%;
}

.sidebar {
    width: 300px;
    background: rgba(15, 23, 42, 0.8);
    border-right: 1px solid var(--glass-border);
    display: flex;
    flex-direction: column;
    padding: 1.5rem;
}

.user-profile {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-bottom: 2rem;
}

.avatar {
    width: 48px;
    height: 48px;
    background: var(--accent-color);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    font-size: 1.25rem;
}

.user-info h3 {
    font-size: 1rem;
    font-weight: 600;
}

.status {
    font-size: 0.75rem;
    display: flex;
    align-items: center;
    gap: 0.25rem;
}

.status.online::before {
    content: "";
    width: 8px;
    height: 8px;
    background: #10b981;
    border-radius: 50%;
}

.connection-info {
    margin-top: auto;
    font-size: 0.75rem;
    color: var(--text-secondary);
}

#disconnect-btn {
    margin-top: 1rem;
    background: transparent;
    border: 1px solid var(--error-color);
    color: var(--error-color);
    padding: 0.5rem;
}

#disconnect-btn:hover {
    background: var(--error-color);
    color: white;
}

.chat-main {
    flex: 1;
    display: flex;
    flex-direction: column;
    background: rgba(15, 23, 42, 0.4);
}

.chat-header {
    padding: 1.25rem 2rem;
    border-bottom: 1px solid var(--glass-border);
    background: rgba(30, 41, 59, 0.5);
}

.messages-list {
    flex: 1;
    padding: 2rem;
    overflow-y: auto;
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.message {
    max-width: 70%;
    padding: 0.75rem 1rem;
    border-radius: 1rem;
    font-size: 0.9375rem;
    line-height: 1.4;
    position: relative;
}

.message.sent {
    align-self: flex-end;
    background-color: var(--msg-sent);
    border-bottom-right-radius: 0.25rem;
}

.message.received {
    align-self: flex-start;
    background-color: var(--msg-received);
    border-bottom-left-radius: 0.25rem;
}

.message-time {
    font-size: 0.7rem;
    opacity: 0.7;
    margin-top: 0.25rem;
    display: block;
    text-align: right;
}

.chat-footer {
    padding: 1.5rem 2rem;
    display: flex;
    gap: 1rem;
    background: rgba(30, 41, 59, 0.5);
    border-top: 1px solid var(--glass-border);
}

#message-input {
    flex: 1;
}

#send-btn {
    width: 48px;
    height: 48px;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 0;
}

.typing-indicator {
    padding: 0.5rem 2rem;
    font-size: 0.8rem;
    color: var(--text-secondary);
    font-style: italic;
    height: 1.5rem;
}

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

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

::-webkit-scrollbar-thumb {
    background: var(--glass-border);
    border-radius: 10px;
}

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