*{margin:0;padding:0;box-sizing:border-box}body{font-family:-apple-system,BlinkMacSystemFont,'Segoe UI',Roboto,'Inter',sans-serif;background:#f5f7fa;min-height:100vh;color:#1a202c;line-height:1.5}.main-navigation{background:#ffffff;padding:0.75rem 2rem;display:flex;justify-content:space-between;align-items:center;box-shadow:0 1px 3px rgba(0,0,0,0.05);margin-bottom:1.25rem}.nav-brand{display:flex;align-items:center;gap:1rem}.logo{width:32px;height:32px;border-radius:6px;background:#2563eb;display:flex;align-items:center;justify-content:center;color:white;font-weight:700;font-size:0.9rem}.app-title{font-size:1.25rem;font-weight:700;color:#1a202c;letter-spacing:-0.02em}.nav-menu{display:flex;list-style:none;gap:0.5rem;align-items:center}.nav-link{text-decoration:none;color:#64748b;font-weight:500;padding:0.5rem 1rem;border-radius:6px;transition:all 0.2s ease;font-size:0.875rem}.nav-link:hover{background:#f1f5f9;color:#2563eb}.nav-link.active{background:#2563eb;color:white}.container{max-width:1200px;margin:0 auto;padding:0 1.5rem}.content-container{background:white;border-radius:10px;padding:1rem;box-shadow:0 1px 3px rgba(0,0,0,0.05);margin-bottom:1rem}.control-panel{display:grid;grid-template-columns:1fr 1.2fr 1fr 1fr;gap:0.875rem;margin-bottom:1rem;padding:1rem;background:white;border-radius:10px;box-shadow:0 1px 3px rgba(0,0,0,0.05)}.control-group{display:flex;flex-direction:column}.control-group label{display:block;color:#475569;margin-bottom:0.375rem;font-weight:600;font-size:0.8rem;text-transform:uppercase;letter-spacing:0.05em}.control-group input,.control-group select{width:100%;padding:0.5rem 0.75rem;border:1.5px solid #e2e8f0;border-radius:6px;background:#ffffff;font-size:0.9rem;color:#1a202c;transition:all 0.2s ease}.control-group input:focus,.control-group select:focus{outline:none;border-color:#2563eb;box-shadow:0 0 0 3px rgba(37,99,235,0.1)}.epoch-input-wrapper{position:relative;display:flex;align-items:center;gap:0.375rem;width:100%}.epoch-input-wrapper input{flex:1;min-width:0}.copy-icon-btn{background:transparent;border:none;color:#64748b;cursor:pointer;padding:0.375rem;border-radius:4px;transition:all 0.2s ease;display:inline-flex;align-items:center;justify-content:center;flex-shrink:0;min-width:32px;min-height:32px;vertical-align:middle;line-height:1}.copy-icon-btn svg{width:16px;height:16px;display:block;pointer-events:none}.copy-icon-btn:hover{background:#f1f5f9;color:#2563eb}.copy-icon-btn:active{transform:scale(0.95)}.dropdown-wrapper{position:relative;width:100%}.dropdown-select{appearance:none;cursor:text}.dropdown-select.select-dropdown{background-image:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 12 12'%3E%3Cpath fill='%2364748b' d='M6 9L1 4h10z'/%3E%3C/svg%3E");background-repeat:no-repeat;background-position:right 1rem center;padding-right:2.5rem;cursor:pointer}.dropdown-custom-input{margin-top:0.5rem;position:relative}#timezone-selector{width:100%}.autocomplete-dropdown{position:absolute;top:calc(100%+0.5rem);left:0;right:0;width:100%;background:white;border:1.5px solid #e2e8f0;border-radius:8px;box-shadow:0 10px 25px rgba(0,0,0,0.1);max-height:300px;overflow-y:auto;z-index:1000;display:none}.autocomplete-item{padding:0.875rem 1rem;cursor:pointer;border-bottom:1px solid #f1f5f9;transition:background-color 0.15s}.autocomplete-item-timezone{display:flex;align-items:center}.autocomplete-item-flag{flex-shrink:0;margin-right:0.5rem;font-size:1.1em}.autocomplete-item-text{font-weight:600;color:#1a202c;min-width:0}.autocomplete-item strong{font-weight:600;color:#1a202c}.autocomplete-item:last-child{border-bottom:none}.autocomplete-item:hover{background-color:#f8fafc}.autocomplete-item:active{background-color:#f1f5f9}.epoch-value-inline{width:100%;padding:0.5rem 0.75rem;border:1.5px solid #e2e8f0;border-radius:6px;font-family:'SF Mono','Monaco','Consolas',monospace;font-size:0.875rem;background:#f8fafc;color:#1a202c}.current-datetime-value{margin-top:0.5rem;padding:0.375rem 0.5rem;font-family:'SF Mono','Monaco','Consolas',monospace;font-size:0.75rem;color:#64748b;text-align:center;background:#f8fafc;border-radius:4px;border:1px solid #e2e8f0}.current-epoch-display{position:absolute;top:0.75rem;right:0.75rem;background:white;border-radius:8px;padding:1rem;box-shadow:0 1px 3px rgba(0,0,0,0.05);min-width:180px}.current-epoch-display label{display:block;color:#475569;font-weight:600;margin-bottom:0.625rem;font-size:0.8rem;text-transform:uppercase;letter-spacing:0.05em}.epoch-value-group{margin-bottom:0.75rem}.epoch-value-group:last-child{margin-bottom:0}.copy-btn{background:#2563eb;color:white;border:none;padding:0.4rem 0.75rem;border-radius:6px;cursor:pointer;font-size:0.8rem;font-weight:600;margin-bottom:0.375rem;transition:all 0.2s ease;width:100%}.copy-btn:hover{background:#1d4ed8}.copy-btn:active{transform:scale(0.98)}.epoch-value{width:100%;padding:0.5rem 0.75rem;border:1.5px solid #e2e8f0;border-radius:6px;font-family:'SF Mono','Monaco','Consolas',monospace;font-size:0.875rem;background:#f8fafc;color:#1a202c}.epoch-rows-container{position:relative}.epoch-row-header{display:grid;grid-template-columns:40px 180px minmax(200px,1fr) minmax(200px,1.2fr);gap:0.875rem;align-items:center;padding:0.625rem 1rem;margin-bottom:0.5rem;font-weight:600;font-size:0.8rem;color:#475569;text-transform:uppercase;letter-spacing:0.05em}.epoch-row-header>div{padding-left:0}.epoch-row{display:grid;grid-template-columns:40px 180px 1fr;gap:0.875rem;align-items:center;padding:0.75rem 1rem;margin-bottom:0.625rem;background:#ffffff;border-radius:8px;border:1.5px solid #e2e8f0;transition:border-color 0.2s ease}.epoch-row:hover{border-color:#cbd5e1}.epoch-row.comparison-row{grid-template-columns:40px 180px minmax(200px,1fr) minmax(200px,1.2fr)}.epoch-row.reference-row{grid-template-columns:40px 180px 1fr}.epoch-row label{color:#475569;font-weight:600;font-size:0.8rem;text-transform:uppercase;letter-spacing:0.05em;align-self:center}.epoch-input{padding:0.5rem 0.75rem;border:1.5px solid #e2e8f0;border-radius:6px;font-size:0.875rem;font-family:'SF Mono','Monaco','Consolas',monospace;transition:all 0.2s ease;background:#ffffff;max-width:180px;width:180px}.epoch-input:focus{outline:none;border-color:#2563eb;box-shadow:0 0 0 3px rgba(37,99,235,0.1)}.epoch-input.invalid{border-color:#ef4444}.converted-date{padding:0.5rem 0.75rem;background:#f8fafc;border-radius:6px;border:1.5px solid #e2e8f0;font-family:'SF Mono','Monaco','Consolas',monospace;color:#1a202c;min-height:38px;display:flex;align-items:center;font-size:0.875rem}.difference-display{padding:0.5rem 0.75rem;background:#eff6ff;border-radius:6px;border:1.5px solid #bfdbfe;display:flex;align-items:center;min-height:38px}.difference-display span{color:#1e3a8a;font-family:'SF Mono','Monaco','Consolas',monospace;font-size:0.875rem;font-weight:500}.add-row-skeleton{cursor:pointer;border-style:dashed !important;border-color:#cbd5e1 !important;background:#f8fafc !important;transition:all 0.2s ease;grid-template-columns:40px 180px minmax(200px,1fr) minmax(200px,1.2fr);align-items:center;min-height:55px}.add-row-skeleton:hover{border-color:#2563eb !important;background:#eff6ff !important}.add-row-skeleton>div{display:none}.add-row-skeleton-btn{grid-column:1 / -1;display:flex;align-items:center;justify-content:center;gap:0.5rem;padding:0.75rem 1rem;background:transparent;border:none;color:#64748b;font-size:0.875rem;font-weight:600;cursor:pointer;transition:all 0.2s ease;width:100%;align-self:center}.add-row-skeleton:hover .add-row-skeleton-btn{color:#2563eb}.add-row-skeleton-btn svg{width:20px;height:20px;stroke:currentColor}.add-row-skeleton-btn span{font-family:-apple-system,BlinkMacSystemFont,'Segoe UI',Roboto,'Inter',sans-serif}.delete-row-btn{width:32px;height:32px;border-radius:6px;background:transparent;color:#64748b;border:1.5px solid #e2e8f0;cursor:pointer;display:flex;align-items:center;justify-content:center;transition:all 0.2s ease;padding:0;flex-shrink:0;justify-self:center;align-self:center;margin:0}.delete-row-btn:hover{background:#fee2e2;color:#dc2626;border-color:#fecaca}.delete-row-btn:active{transform:scale(0.95);background:#fecaca}.delete-row-btn svg{width:16px;height:16px}@media (max-width:768px){.main-navigation{flex-direction:column;gap:0.75rem;padding:0.75rem}.nav-menu{flex-direction:column;gap:0.25rem;width:100%}.nav-link{display:block;text-align:center;width:100%}.container{padding:0 0.75rem}.content-container{padding:1rem}.control-panel{grid-template-columns:1fr;padding:1rem;gap:0.75rem}.current-datetime-value{font-size:0.7rem;padding:0.375rem 0.5rem}.epoch-row{grid-template-columns:1fr;gap:0.625rem;padding:0.875rem}.epoch-row.comparison-row,.epoch-row.reference-row{grid-template-columns:1fr}.epoch-input{width:100%;max-width:100%}.current-epoch-display{position:relative;top:auto;right:auto;margin-bottom:1rem}.add-row-skeleton-btn{padding:0.625rem 0.875rem;font-size:0.8125rem}.add-row-skeleton-btn svg{width:18px;height:18px}}.text-center{text-align:center}.mt-1{margin-top:0.5rem}.mt-2{margin-top:1rem}.mt-3{margin-top:1.5rem}.mb-1{margin-bottom:0.5rem}.mb-2{margin-bottom:1rem}.mb-3{margin-bottom:1.5rem}.error-message{color:#ef4444;font-size:0.875rem;margin-top:0.5rem;font-weight:500}.success-message{color:#10b981;font-size:0.875rem;margin-top:0.5rem;font-weight:500}