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

:root {
    --gold: #d4a017;
    --gold-light: #f0d060;
    --black: #1a1a1a;
    --white: #ffffff;
    --gray-light: #f5f5f5;
    --gray-mid: #e0e0e0;
    --gray-text: #666;
    --danger: #c0392b;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    background: var(--gray-light);
    color: var(--black);
    min-height: 100dvh;
}

#app {
    max-width: 600px;
    margin: 0 auto;
    min-height: 100dvh;
    display: flex;
    flex-direction: column;
    background: var(--white);
}

/* Header */
#app-header {
    background: var(--black);
    color: var(--gold);
    padding: 12px 16px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

#app-header h1 {
    font-size: 20px;
    font-weight: 700;
    letter-spacing: 0.5px;
}

.header-btn {
    background: transparent;
    color: var(--gold);
    border: 1px solid var(--gold);
    padding: 6px 14px;
    border-radius: 4px;
    cursor: pointer;
    font-size: 14px;
}

.header-btn:hover {
    background: var(--gold);
    color: var(--black);
}

/* Main content */
#main {
    flex: 1;
    display: flex;
    flex-direction: column;
}

/* Forms (login, register) */
.auth-form {
    padding: 32px 24px;
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.auth-form h2 {
    font-size: 24px;
    color: var(--black);
    margin-bottom: 8px;
}

.form-group {
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.form-group label {
    font-size: 13px;
    font-weight: 600;
    color: var(--gray-text);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.form-group input {
    padding: 10px 12px;
    border: 1px solid var(--gray-mid);
    border-radius: 4px;
    font-size: 16px;
    outline: none;
}

.form-group input:focus {
    border-color: var(--gold);
}

.btn {
    padding: 12px;
    border: none;
    border-radius: 4px;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
}

.btn-primary {
    background: var(--gold);
    color: var(--black);
}

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

.btn-primary:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

.auth-link {
    text-align: center;
    font-size: 14px;
    color: var(--gray-text);
}

.auth-link a {
    color: var(--gold);
    text-decoration: none;
    font-weight: 600;
}

.error-msg {
    color: var(--danger);
    font-size: 14px;
    padding: 8px 12px;
    background: #fdf0ef;
    border-radius: 4px;
    display: none;
}

.status-msg {
    color: var(--gray-text);
    font-size: 14px;
    padding: 8px 12px;
    text-align: center;
}

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

.user-item {
    padding: 16px;
    border-bottom: 1px solid var(--gray-mid);
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 12px;
}

.user-item:hover {
    background: var(--gray-light);
}

.user-avatar {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background: var(--black);
    color: var(--gold);
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    font-size: 16px;
    flex-shrink: 0;
}

.user-name {
    font-size: 16px;
    font-weight: 600;
}

/* Chat view */
.chat-view {
    flex: 1;
    display: flex;
    flex-direction: column;
}

.chat-header {
    padding: 12px 16px;
    border-bottom: 1px solid var(--gray-mid);
    display: flex;
    align-items: center;
    gap: 12px;
}

.chat-back {
    background: none;
    border: none;
    font-size: 20px;
    cursor: pointer;
    color: var(--gold);
    padding: 4px 8px;
}

.chat-partner-name {
    font-size: 18px;
    font-weight: 600;
}

.chat-messages {
    flex: 1;
    overflow-y: auto;
    padding: 16px;
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.message {
    max-width: 80%;
    padding: 10px 14px;
    border-radius: 12px;
    font-size: 15px;
    line-height: 1.4;
    word-wrap: break-word;
}

.message-sent {
    align-self: flex-end;
    background: var(--gold);
    color: var(--black);
    border-bottom-right-radius: 4px;
}

.message-received {
    align-self: flex-start;
    background: var(--gray-light);
    color: var(--black);
    border-bottom-left-radius: 4px;
}

.message-time {
    font-size: 11px;
    color: var(--gray-text);
    margin-top: 4px;
}

.message-sent .message-time {
    text-align: right;
}

.chat-compose {
    padding: 12px;
    border-top: 1px solid var(--gray-mid);
    display: flex;
    gap: 8px;
}

.chat-compose input {
    flex: 1;
    padding: 10px 12px;
    border: 1px solid var(--gray-mid);
    border-radius: 20px;
    font-size: 16px;
    outline: none;
}

.chat-compose input:focus {
    border-color: var(--gold);
}

.chat-compose button {
    background: var(--gold);
    color: var(--black);
    border: none;
    border-radius: 50%;
    width: 40px;
    height: 40px;
    font-size: 18px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
}

.chat-compose button:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}