/* ============================================
   全局樣式
   ============================================ */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary-color: #667eea;
    --primary-hover: #5a67d8;
    --secondary-color: #718096;
    --success-color: #48bb78;
    --danger-color: #f56565;
    --warning-color: #ed8936;
    --bg-dark: #1a202c;
    --bg-light: #2d3748;
    --bg-lighter: #4a5568;
    --text-primary: #ffffff;
    --text-secondary: #a0aec0;
    --border-color: #4a5568;
    --shadow: 0 4px 6px rgba(0, 0, 0, 0.3);
    --shadow-lg: 0 10px 25px rgba(0, 0, 0, 0.4);
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Microsoft JhengHei', sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    color: var(--text-primary);
}

.container {
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    padding: 20px;
}

/* ============================================
   按鈕樣式
   ============================================ */
.btn {
    padding: 12px 24px;
    border: none;
    border-radius: 8px;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

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

.btn-primary:hover {
    background: var(--primary-hover);
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.btn-success {
    background: var(--success-color);
    color: white;
}

.btn-success:hover {
    background: #38a169;
    transform: translateY(-2px);
}

.btn-danger {
    background: var(--danger-color);
    color: white;
}

.btn-danger:hover {
    background: #e53e3e;
}

.btn-secondary {
    background: var(--secondary-color);
    color: white;
}

.btn-secondary:hover {
    background: #4a5568;
}

.btn-sm {
    padding: 8px 16px;
    font-size: 14px;
}

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

/* ============================================
   登入頁面
   ============================================ */
.login-box {
    background: var(--bg-dark);
    padding: 40px;
    border-radius: 20px;
    box-shadow: var(--shadow-lg);
    max-width: 500px;
    width: 100%;
    text-align: center;
}

.game-title {
    font-size: 2.5rem;
    margin-bottom: 10px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.subtitle {
    color: var(--text-secondary);
    margin-bottom: 30px;
    font-size: 1.1rem;
}

.login-form {
    margin-bottom: 30px;
}

.form-group {
    margin-bottom: 25px;
    text-align: left;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    color: var(--text-secondary);
    font-weight: 500;
}

.form-group input[type="text"] {
    width: 100%;
    padding: 12px;
    border: 2px solid var(--border-color);
    border-radius: 8px;
    background: var(--bg-light);
    color: var(--text-primary);
    font-size: 16px;
    transition: border-color 0.3s;
}

.form-group input[type="text"]:focus {
    outline: none;
    border-color: var(--primary-color);
}

.avatar-selector {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 10px;
    margin-top: 10px;
}

.avatar-option {
    font-size: 2rem;
    padding: 15px;
    background: var(--bg-light);
    border-radius: 10px;
    cursor: pointer;
    transition: all 0.3s;
    border: 2px solid transparent;
}

.avatar-option:hover {
    transform: scale(1.1);
    background: var(--bg-lighter);
}

.avatar-option.selected {
    border-color: var(--primary-color);
    background: var(--primary-color);
    transform: scale(1.1);
}

.stats-preview {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
    padding-top: 20px;
    border-top: 1px solid var(--border-color);
}

.stat {
    text-align: center;
}

.stat-value {
    display: block;
    font-size: 2rem;
    font-weight: bold;
    color: var(--primary-color);
}

.stat-label {
    display: block;
    color: var(--text-secondary);
    font-size: 0.9rem;
    margin-top: 5px;
}

/* ============================================
   大廳頁面
   ============================================ */
.lobby-page {
    background: var(--bg-dark);
}

.lobby-container {
    display: grid;
    grid-template-columns: 300px 1fr;
    height: 100vh;
    max-width: 1600px;
    margin: 0 auto;
}

/* 側邊欄 */
.sidebar {
    background: var(--bg-light);
    padding: 20px;
    border-right: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
    gap: 20px;
    overflow-y: auto;
}

.user-profile {
    background: var(--bg-lighter);
    padding: 20px;
    border-radius: 12px;
    text-align: center;
}

.avatar-display {
    font-size: 4rem;
    margin-bottom: 10px;
}

.user-info h3 {
    margin-bottom: 10px;
}

.user-score {
    color: var(--warning-color);
    font-weight: bold;
    font-size: 1.2rem;
    margin: 10px 0;
}

.user-record {
    display: flex;
    justify-content: space-around;
    margin-top: 10px;
    font-size: 0.9rem;
}

.user-record .wins {
    color: var(--success-color);
}

.user-record .losses {
    color: var(--danger-color);
}

.user-record .draws {
    color: var(--text-secondary);
}

.logout-btn {
    width: 100%;
}

.leaderboard {
    flex: 1;
    background: var(--bg-lighter);
    padding: 15px;
    border-radius: 12px;
}

.leaderboard h3 {
    margin-bottom: 15px;
    text-align: center;
}

.leaderboard-list {
    max-height: 400px;
    overflow-y: auto;
}

.leaderboard-item {
    display: flex;
    align-items: center;
    padding: 10px;
    background: var(--bg-light);
    border-radius: 8px;
    margin-bottom: 8px;
}

.leaderboard-item .rank {
    font-weight: bold;
    font-size: 1.2rem;
    margin-right: 10px;
    min-width: 30px;
}

.leaderboard-item .rank.top1 { color: #ffd700; }
.leaderboard-item .rank.top2 { color: #c0c0c0; }
.leaderboard-item .rank.top3 { color: #cd7f32; }

.leaderboard-item .player-avatar {
    font-size: 1.5rem;
    margin-right: 10px;
}

.leaderboard-item .player-details {
    flex: 1;
}

.leaderboard-item .player-name {
    font-weight: 600;
}

.leaderboard-item .player-score {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

/* 主要內容 */
.main-content {
    padding: 30px;
    overflow-y: auto;
}

.lobby-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 30px;
}

.online-status {
    display: flex;
    align-items: center;
    gap: 8px;
    color: var(--text-secondary);
}

.status-dot {
    width: 10px;
    height: 10px;
    background: var(--success-color);
    border-radius: 50%;
    animation: pulse 2s infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.5; }
}

/* 玩家列表 */
.players-section {
    margin-bottom: 30px;
}

.players-section h2 {
    margin-bottom: 20px;
}

.players-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
    gap: 20px;
}

.player-card {
    background: var(--bg-light);
    padding: 20px;
    border-radius: 12px;
    text-align: center;
    transition: all 0.3s;
    position: relative;
}

.player-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
}

.player-card .player-avatar {
    font-size: 3rem;
    margin-bottom: 10px;
}

.player-card .player-name {
    font-size: 1.2rem;
    margin-bottom: 5px;
}

.player-card .player-score {
    color: var(--warning-color);
    margin-bottom: 10px;
}

.player-card .player-status {
    display: inline-block;
    padding: 4px 12px;
    border-radius: 20px;
    font-size: 0.8rem;
    margin-bottom: 10px;
}

.player-status.idle {
    background: var(--success-color);
}

.player-status.in-game {
    background: var(--warning-color);
}

.player-card .challenge-btn {
    width: 100%;
    padding: 10px;
    background: var(--primary-color);
    color: white;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.3s;
}

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

.player-card .challenge-btn:disabled {
    background: var(--secondary-color);
    cursor: not-allowed;
}

/* 聊天區 */
.chat-section {
    background: var(--bg-light);
    padding: 20px;
    border-radius: 12px;
}

.chat-section h3 {
    margin-bottom: 15px;
}

.chat-box {
    display: flex;
    flex-direction: column;
    height: 300px;
}

.chat-messages {
    flex: 1;
    overflow-y: auto;
    padding: 15px;
    background: var(--bg-dark);
    border-radius: 8px;
    margin-bottom: 10px;
}

.chat-message {
    margin-bottom: 10px;
    padding: 8px 12px;
    background: var(--bg-lighter);
    border-radius: 8px;
}

.chat-message .sender {
    font-weight: bold;
    color: var(--primary-color);
    margin-right: 5px;
}

.chat-message .text {
    color: var(--text-primary);
}

.chat-message .timestamp {
    font-size: 0.7rem;
    color: var(--text-secondary);
    margin-left: 5px;
}

.chat-input-container {
    display: flex;
    gap: 10px;
}

.chat-input-container input {
    flex: 1;
    padding: 10px;
    border: 2px solid var(--border-color);
    border-radius: 8px;
    background: var(--bg-dark);
    color: var(--text-primary);
}

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

/* ============================================
   彈窗
   ============================================ */
.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.8);
    justify-content: center;
    align-items: center;
    z-index: 1000;
}

.modal.active {
    display: flex;
}

.modal-content {
    background: var(--bg-light);
    padding: 30px;
    border-radius: 16px;
    max-width: 500px;
    width: 90%;
    text-align: center;
    box-shadow: var(--shadow-lg);
}

.modal-content h3 {
    margin-bottom: 20px;
    font-size: 1.8rem;
}

.challenge-mode {
    color: var(--text-secondary);
    margin: 15px 0;
}

.modal-actions {
    display: flex;
    gap: 15px;
    justify-content: center;
    margin-top: 25px;
}

.spinner {
    width: 50px;
    height: 50px;
    border: 4px solid var(--border-color);
    border-top-color: var(--primary-color);
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin: 20px auto;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

/* ============================================
   工具類
   ============================================ */
.loading {
    text-align: center;
    padding: 20px;
    color: var(--text-secondary);
}

/* ============================================
   響應式設計
   ============================================ */
@media (max-width: 768px) {
    .lobby-container {
        grid-template-columns: 1fr;
    }
    
    .sidebar {
        display: none;
    }
    
    .players-grid {
        grid-template-columns: 1fr;
    }
}