.app-header{background-color:var(--card-background-color);box-shadow:0 2px 4px #0000000d;padding:0 2rem;width:100%;position:fixed;top:0;left:0;z-index:1000}.app-nav{display:flex;justify-content:space-between;align-items:center;max-width:1200px;margin:0 auto;height:64px}.nav-brand{font-size:1.5rem;font-weight:700;color:var(--text-color);text-decoration:none}.nav-links{list-style:none;display:flex;align-items:center;gap:20px;margin:0;padding:0}.nav-links a{text-decoration:none;color:var(--text-color);font-weight:500;padding:8px 12px;border-radius:5px;transition:background-color .2s,color .2s}.nav-links a:hover{background-color:#f1f3f5}.nav-links a.active{color:var(--primary-color);font-weight:700}.user-welcome{color:#555}.logout-button-header{padding:8px 16px;border-radius:5px;border:none;background-color:var(--primary-color);color:#fff;font-weight:700;cursor:pointer;transition:background-color .2s}.logout-button-header:hover{background-color:var(--primary-hover-color)}body{padding-top:64px}#root{display:flex;flex-direction:column;min-height:100vh;justify-content:center;align-items:center}.app-content{padding-top:64px;width:100%;display:flex;justify-content:center;padding-bottom:2rem}.auth-container{background-color:var(--card-background-color);padding:40px;border-radius:8px;box-shadow:var(--box-shadow);width:100%;max-width:400px;text-align:center}.auth-container h2{margin-top:0;margin-bottom:24px}.auth-form{display:flex;flex-direction:column;gap:15px}.auth-form input{padding:12px;border:1px solid var(--border-color);border-radius:5px;font-size:1rem}.auth-form button{padding:12px;border-radius:5px;border:none;background-color:var(--primary-color);color:#fff;font-size:1rem;transition:background-color .2s}.auth-form button:hover{background-color:var(--primary-hover-color)}.auth-switch{margin-top:20px;font-size:.9rem}.auth-switch a{color:var(--primary-color);text-decoration:none;font-weight:700}.error-message{color:#d32f2f;margin-top:15px;font-weight:700}.calculator-container{background-color:var(--card-background-color);padding:32px;border-radius:8px;box-shadow:var(--box-shadow)}.calculator-container h2{margin-top:0;text-align:center;color:var(--text-color);font-size:1.8rem}.calculator-form{display:flex;flex-wrap:wrap;justify-content:center;align-items:center;gap:15px;margin:30px 0}.calculator-form input,.calculator-form select{padding:12px;border-radius:5px;border:1px solid var(--border-color);font-size:1.1rem;text-align:center}.calculator-form input{width:120px}.calculator-form button{padding:12px 24px;border-radius:5px;border:none;background-color:var(--primary-color);color:#fff;font-size:1.1rem;transition:background-color .2s}.calculator-form button:hover{background-color:var(--primary-hover-color)}.calculator-form button:disabled{background-color:#ccc;cursor:not-allowed}.result-display{text-align:center;margin:30px auto;padding:20px;background-color:#e3f2fd;border-left:5px solid var(--primary-color);max-width:50%}.result-display h3{margin:0;font-size:1.8rem;color:var(--text-color)}.result-display span{font-weight:700;color:#0d47a1}.error-message{color:#d32f2f;text-align:center;font-weight:700;margin-top:15px}.history-container h3{border-bottom:2px solid var(--border-color);padding-bottom:8px;margin-top:40px}.history-container ul{list-style-type:none;padding:0;max-height:300px;overflow-y:auto}.history-container li{padding:12px 8px;border-bottom:1px solid #f1f3f5;font-family:SFMono-Regular,Consolas,Liberation Mono,Menlo,Courier,monospace;font-size:1.1rem;transition:background-color .2s;display:flex;justify-content:center}.history-container li:hover{background-color:#f8f9fa}.history-container li:last-child{border-bottom:none}.dashboard-container{width:100%;max-width:900px;margin:2rem auto;padding:1rem 2rem}.dashboard-header{display:flex;justify-content:space-between;align-items:center;border-bottom:2px solid var(--border-color);padding-bottom:1rem;margin-bottom:2rem}.dashboard-header h2{margin:0;font-size:2rem}.user-info{display:flex;align-items:center;gap:15px}.logout-button{padding:8px 16px;border-radius:5px;border:1px solid var(--border-color);background-color:#f8f9fa;color:var(--text-color);transition:background-color .2s,border-color .2s}.logout-button:hover{background-color:#e9ecef;border-color:#adb5bd}.posts-container{max-width:1200px;margin:0 auto;padding:2rem;min-height:calc(100vh - 80px)}.posts-container h1{color:#2c3e50;text-align:center;margin-bottom:2rem;font-size:2.5rem;font-weight:600}.loading{text-align:center;padding:3rem;font-size:1.2rem;color:#666;background:#f8f9fa;border-radius:10px;margin:2rem 0}.error-message{background:#ffeaea;color:#e74c3c;padding:1.5rem;border-radius:8px;margin-bottom:2rem;border-left:4px solid #e74c3c;text-align:center}.no-posts{text-align:center;padding:4rem 2rem;background:linear-gradient(135deg,#667eea,#764ba2);border-radius:12px;color:#fff;margin:2rem 0}.no-posts h3{font-size:1.5rem;margin-bottom:1rem}.no-posts p{font-size:1.1rem;opacity:.9;line-height:1.5}.posts-list{display:grid;grid-template-columns:repeat(auto-fill,minmax(400px,1fr));gap:2rem;margin-top:2rem}.post-item{background:#fff;border-radius:12px;padding:1.5rem;box-shadow:0 4px 20px #0000001a;border:1px solid #e9ecef;transition:all .3s ease;position:relative;overflow:hidden}.post-item:hover{transform:translateY(-5px);box-shadow:0 8px 30px #00000026}.post-item:before{content:"";position:absolute;top:0;left:0;width:4px;height:100%;background:linear-gradient(135deg,#667eea,#764ba2)}.post-item h3{color:#2c3e50;font-size:1.3rem;margin-bottom:1rem;font-weight:600;line-height:1.3}.post-description{color:#666;line-height:1.5;margin-bottom:1.5rem;font-size:.95rem}.calculation-preview{background:#f8f9fa;padding:1rem;border-radius:8px;margin-bottom:1.5rem;border:1px solid #e9ecef}.calculation-preview strong{color:#2c3e50;display:block;margin-bottom:.5rem;font-size:.9rem;text-transform:uppercase;letter-spacing:.5px}.calculation-formula{font-family:Courier New,monospace;font-size:1.2rem;font-weight:700;color:#2c3e50;text-align:center;padding:.5rem;background:#fff;border-radius:4px;border:1px solid #dee2e6}.post-meta{border-top:1px solid #e9ecef;padding-top:1rem;display:flex;justify-content:space-between;align-items:center;flex-wrap:wrap;gap:.5rem}.post-date{color:#6c757d;font-size:.85rem;font-style:italic}.post-actions{display:flex;gap:.5rem}.action-button{padding:.4rem .8rem;border:none;border-radius:4px;font-size:.8rem;cursor:pointer;transition:all .2s;text-decoration:none;display:inline-flex;align-items:center;gap:.3rem}.edit-button{background:#3498db;color:#fff}.edit-button:hover{background:#2980b9}.delete-button{background:#e74c3c;color:#fff}.delete-button:hover{background:#c0392b}.empty-state{text-align:center;padding:4rem 2rem;background:#f8f9fa;border-radius:12px;border:2px dashed #dee2e6}.empty-state-icon{font-size:3rem;color:#6c757d;margin-bottom:1rem}.empty-state h3{color:#2c3e50;margin-bottom:1rem;font-size:1.5rem}.empty-state p{color:#6c757d;margin-bottom:2rem;line-height:1.5}.cta-button{background:linear-gradient(135deg,#667eea,#764ba2);color:#fff;padding:.75rem 1.5rem;border:none;border-radius:6px;font-size:1rem;font-weight:600;cursor:pointer;text-decoration:none;display:inline-flex;align-items:center;gap:.5rem;transition:all .3s}.cta-button:hover{transform:translateY(-2px);box-shadow:0 4px 12px #667eea66}@media(max-width:768px){.posts-container{padding:1rem}.posts-container h1{font-size:2rem}.posts-list{grid-template-columns:1fr;gap:1.5rem}.post-item{padding:1.25rem}.post-meta{flex-direction:column;align-items:flex-start;gap:.75rem}.post-actions{width:100%;justify-content:flex-end}.empty-state{padding:2rem 1rem}}@media(max-width:480px){.posts-container{padding:.5rem}.posts-container h1{font-size:1.75rem}.post-item{padding:1rem}.calculation-formula{font-size:1rem}}@keyframes fadeIn{0%{opacity:0;transform:translateY(10px)}to{opacity:1;transform:translateY(0)}}.post-item{animation:fadeIn .5s ease-out}.posts-list::-webkit-scrollbar{width:6px}.posts-list::-webkit-scrollbar-track{background:#f1f1f1;border-radius:3px}.posts-list::-webkit-scrollbar-thumb{background:#c1c1c1;border-radius:3px}.posts-list::-webkit-scrollbar-thumb:hover{background:#a8a8a8}.comments-section{margin-top:1.5rem;padding-top:1rem;border-top:1px solid #eee}.comments-title{color:#333;font-size:1.1rem;margin-bottom:1rem;font-weight:600}.comments-list{margin-bottom:1.5rem}.comment-item{background:#f8f9fa;border-radius:8px;padding:1rem;margin-bottom:.75rem;border-left:3px solid #667eea}.comment-header{display:flex;justify-content:space-between;align-items:center;margin-bottom:.5rem}.comment-author{font-weight:600;color:#2c3e50;font-size:.9rem}.comment-date{color:#6c757d;font-size:.8rem;font-style:italic}.comment-content{color:#333;line-height:1.4;margin:0;font-size:.9rem}.no-comments{color:#6c757d;font-style:italic;text-align:center;padding:1rem;background:#f8f9fa;border-radius:6px;margin-bottom:1.5rem}.add-comment{margin-top:1rem}.comment-input{width:100%;padding:.75rem;border:1px solid #ddd;border-radius:6px;font-family:inherit;font-size:.9rem;resize:vertical;margin-bottom:.5rem;box-sizing:border-box}.comment-input:focus{outline:none;border-color:#667eea;box-shadow:0 0 0 2px #667eea1a}.comment-submit-btn{background:linear-gradient(135deg,#667eea,#764ba2);color:#fff;border:none;padding:.5rem 1.5rem;border-radius:6px;font-size:.9rem;font-weight:500;cursor:pointer;transition:all .3s}.comment-submit-btn:hover:not(:disabled){transform:translateY(-1px);box-shadow:0 4px 12px #667eea66}.comment-submit-btn:disabled{background:#bdc3c7;cursor:not-allowed;transform:none;box-shadow:none}@media(max-width:768px){.comment-header{flex-direction:column;align-items:flex-start;gap:.25rem}.comment-date{align-self:flex-end}}.comment-input.error{border-color:#f44;box-shadow:0 0 0 2px #f443}.comment-error{color:#f44;font-size:.875rem;margin-top:.25rem;margin-bottom:.5rem}.comment-submit-btn:disabled{background-color:#ccc;cursor:not-allowed}:root{--primary-color: #007bff;--primary-hover-color: #0056b3;--background-color: #f4f7f9;--card-background-color: #ffffff;--text-color: #333333;--border-color: #dee2e6;--box-shadow: 0 4px 12px rgba(0, 0, 0, .08)}body{margin:0;font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Helvetica,Arial,sans-serif;background-color:var(--background-color);color:var(--text-color);-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale}button{cursor:pointer;font-family:inherit;font-weight:700}