.join-board-container{min-height:100vh;display:flex;justify-content:center;align-items:center;background:linear-gradient(135deg,#f5f7fa,#c3cfe2);padding:20px}.join-board-card{background:#fff;border-radius:8px;padding:32px;width:100%;max-width:400px;text-align:center;box-shadow:0 4px 6px #0000001a}.join-board-card h1{margin:0 0 16px;color:#333;font-size:24px}.join-board-card p{color:#666;margin-bottom:24px}.join-button{background:#28a745;color:#fff;border:none;padding:12px 24px;border-radius:4px;font-size:16px;font-weight:500;cursor:pointer;transition:background-color .2s}.join-button:hover{background:#218838}.loading-spinner{display:flex;align-items:center;justify-content:center}.error-message{background:#fff;border-radius:8px;padding:32px;width:100%;max-width:400px;text-align:center;box-shadow:0 4px 6px #0000001a}.error-message .material-icons{font-size:48px;color:#dc3545;margin-bottom:16px}.error-message h2{margin:0 0 16px;color:#333}.error-message p{color:#666;margin-bottom:24px}.back-button{background:#6c757d;color:#fff;border:none;padding:12px 24px;border-radius:4px;font-size:16px;font-weight:500;cursor:pointer;transition:background-color .2s}.back-button:hover{background:#5a6268}