.mailbox-list{padding:12px 0}.mailbox-list-loading{display:flex;justify-content:center;padding:40px}.spinner-small{width:24px;height:24px;border:3px solid #f3f3f3;border-top:3px solid #3498db;border-radius:50%;animation:spin 1s linear infinite}.mailbox-list-error{padding:20px;color:#c33;text-align:center;font-size:14px}.mailbox-item{-webkit-user-select:none;user-select:none}.mailbox-row{display:flex;align-items:center;gap:8px;padding:8px 12px;cursor:pointer;transition:background-color .15s}.mailbox-row:hover{background-color:#f5f5f5}.mailbox-expand{background:none;border:none;cursor:pointer;padding:0;width:16px;height:16px;display:flex;align-items:center;justify-content:center;font-size:10px;color:#666}.mailbox-icon{font-size:16px}.mailbox-name{flex:1;font-size:14px;color:#333}.mailbox-unread{background-color:#3498db;color:#fff;font-size:12px;font-weight:700;padding:2px 6px;border-radius:10px;min-width:20px;text-align:center}.app-loading{display:flex;flex-direction:column;align-items:center;justify-content:center;min-height:100vh;gap:20px}.spinner{width:40px;height:40px;border:4px solid #f3f3f3;border-top:4px solid #3498db;border-radius:50%;animation:spin 1s linear infinite}@keyframes spin{0%{transform:rotate(0)}to{transform:rotate(360deg)}}.sign-in-screen{display:flex;align-items:center;justify-content:center;min-height:100vh;background:linear-gradient(135deg,#667eea,#764ba2)}.sign-in-card{background:#fff;padding:40px;border-radius:8px;box-shadow:0 4px 6px #0000001a;text-align:center;max-width:400px}.sign-in-card h1{font-size:32px;margin-bottom:10px;color:#333}.sign-in-card p{color:#666;margin-bottom:30px}.sign-in-button{background-color:#667eea;color:#fff;border:none;padding:12px 24px;font-size:16px;border-radius:4px;cursor:pointer;transition:background-color .2s}.sign-in-button:hover{background-color:#5568d3}.error-message{background-color:#fee;color:#c33;padding:10px;border-radius:4px;margin-bottom:20px;font-size:14px}.mail-app{display:flex;flex-direction:column;height:100vh}.mail-header{display:flex;justify-content:space-between;align-items:center;padding:16px 24px;background-color:#fff;border-bottom:1px solid #e0e0e0}.mail-header h1{font-size:24px;color:#333}.user-info{display:flex;align-items:center;gap:16px}.user-info span{color:#666;font-size:14px}.sign-out-button{background-color:#f5f5f5;color:#333;border:1px solid #ddd;padding:8px 16px;font-size:14px;border-radius:4px;cursor:pointer;transition:background-color .2s}.sign-out-button:hover{background-color:#e0e0e0}.mail-body{display:flex;flex:1;overflow:hidden}.mailbox-sidebar{width:250px;background-color:#fff;border-right:1px solid #e0e0e0;overflow-y:auto}.message-area{flex:1;background-color:#fafafa;display:flex;align-items:center;justify-content:center}.empty-state{color:#999;text-align:center}*{margin:0;padding:0;box-sizing:border-box}body{font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Oxygen,Ubuntu,Cantarell,Fira Sans,Droid Sans,Helvetica Neue,sans-serif;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale;background-color:#f5f5f5}code{font-family:source-code-pro,Menlo,Monaco,Consolas,Courier New,monospace}#root{min-height:100vh}