:root{--bg-primary: #ffffff;--bg-secondary: #f5f7fa;--bg-card: #ffffff;--bg-input: #ffffff;--text-primary: #1a1a1a;--text-secondary: #555555;--text-muted: #888888;--border-color: #d8dce2;--border-focus: #1a73e8;--accent-blue: #1a73e8;--accent-blue-hover: #1558b0;--accent-amber: #e07b00;--accent-red: #c5221f;--accent-green: #188038;--table-stripe: #f9fafc;--table-header-bg: #f0f2f5;--table-border: #e0e3e8;--shadow-sm: 0 1px 3px rgba(0, 0, 0, .08);--shadow-md: 0 2px 8px rgba(0, 0, 0, .1);--radius: 6px;--font: system-ui, -apple-system, "Segoe UI", sans-serif}[data-theme=dark]{--bg-primary: #121212;--bg-secondary: #1a1a1a;--bg-card: #1e1e1e;--bg-input: #2a2a2a;--text-primary: #e8eaed;--text-secondary: #9aa0a6;--text-muted: #6e7680;--border-color: #3c3c3c;--border-focus: #8ab4f8;--accent-blue: #8ab4f8;--accent-blue-hover: #adc8ff;--accent-amber: #ffa94d;--accent-red: #f28b82;--accent-green: #81c995;--table-stripe: #232323;--table-header-bg: #252525;--table-border: #333333;--shadow-sm: 0 1px 3px rgba(0, 0, 0, .4);--shadow-md: 0 2px 8px rgba(0, 0, 0, .5)}*,*:before,*:after{box-sizing:border-box;margin:0;padding:0}html{font-size:15px}body{font-family:var(--font);background-color:var(--bg-secondary);color:var(--text-primary);line-height:1.5;min-height:100vh;transition:background-color .2s,color .2s}header{padding:1.5rem 1.5rem 0}header h1{font-size:1.25rem;font-weight:600;color:var(--text-primary)}main{max-width:1100px;margin:0 auto;padding:1.5rem;display:flex;flex-direction:column;gap:1.5rem}section,#chart-section,#table-section{background-color:var(--bg-card);border:1px solid var(--border-color);border-radius:var(--radius);box-shadow:var(--shadow-sm);padding:1.5rem}section h2,#chart-section h2,#table-section h2{font-size:1rem;font-weight:600;margin-bottom:1rem;color:var(--text-primary)}#results{background:none;border:none;box-shadow:none;padding:0;display:flex;flex-direction:column;gap:1.5rem}.form-grid{display:grid;grid-template-columns:repeat(2,minmax(200px,320px));gap:0 2rem}@media(max-width:680px){.form-grid{grid-template-columns:1fr}}.form-col{display:flex;flex-direction:column;gap:1rem}.form-group{display:flex;flex-direction:column;gap:.35rem;position:relative}label,.group-label{font-size:.85rem;font-weight:500;color:var(--text-secondary)}input[type=number],input[type=month],select{width:100%;padding:.5rem .75rem;background-color:var(--bg-input);color:var(--text-primary);border:1px solid var(--border-color);border-radius:var(--radius);font-size:.95rem;font-family:var(--font);transition:border-color .15s;outline:none;-webkit-appearance:none}input[type=number]:focus,input[type=month]:focus,select:focus{border-color:var(--border-focus);box-shadow:0 0 0 3px #1a73e826}[data-theme=dark] input[type=number]:focus,[data-theme=dark] input[type=month]:focus,[data-theme=dark] select:focus{box-shadow:0 0 0 3px #8ab4f833}input[readonly]{background-color:var(--bg-secondary);color:var(--text-muted);cursor:default}input.derived{background-color:var(--bg-secondary);color:var(--text-muted);font-style:italic}.input-prefix-wrap{display:flex;align-items:stretch}.input-prefix{display:flex;align-items:center;padding:.5rem .6rem;background-color:var(--table-header-bg);border:1px solid var(--border-color);border-right:none;border-radius:var(--radius) 0 0 var(--radius);font-size:.9rem;color:var(--text-secondary);white-space:nowrap;user-select:none}.input-prefix-wrap input{border-radius:0 var(--radius) var(--radius) 0;flex:1}.term-input-row{display:flex;align-items:center;gap:.5rem}.term-input-row input{width:4rem;flex:none}.term-sep{display:none}.term-unit{font-size:.82rem;color:var(--text-muted);white-space:nowrap;flex-shrink:0}.radio-group{display:flex;flex-direction:column;gap:.4rem}.radio-label{display:flex;align-items:center;gap:.5rem;font-size:.9rem;font-weight:400;color:var(--text-primary);cursor:pointer}.radio-label input[type=radio]{width:auto;margin:0;accent-color:var(--accent-blue)}.derived-badge{display:none;font-size:.7rem;font-weight:500;color:var(--accent-blue);text-transform:uppercase;letter-spacing:.04em;position:absolute;right:.5rem;bottom:.6rem;pointer-events:none}.is-derived .derived-badge{display:block}#overpayments-section{margin-top:1.25rem;border-top:1px solid var(--border-color);padding-top:1rem}#overpayments-section>summary{font-size:.9rem;font-weight:500;color:var(--text-secondary);cursor:pointer;user-select:none;list-style:none;display:flex;align-items:center;gap:.5rem}#overpayments-section>summary:before{content:"▶";font-size:.65rem;transition:transform .15s;color:var(--text-muted)}#overpayments-section[open]>summary:before{transform:rotate(90deg)}.optional-label{font-weight:400;color:var(--text-muted)}.overpayments-inner{margin-top:1rem;display:flex;flex-direction:column;gap:1rem}.lump-sum-row{display:flex;align-items:center;gap:.5rem}.lump-sum-row input[type=month],.lump-sum-row input[type=number]{flex:1}.lump-sum-remove{background:none;border:1px solid var(--border-color);border-radius:var(--radius);padding:.4rem .6rem;color:var(--accent-red);font-size:.9rem;cursor:pointer;line-height:1;flex-shrink:0;transition:background-color .15s}.lump-sum-remove:hover{background-color:var(--bg-secondary)}.error-container{margin-top:1rem;padding:.75rem 1rem;background-color:#c5221f14;border:1px solid rgba(197,34,31,.3);border-radius:var(--radius);color:var(--accent-red);font-size:.875rem}.error-container ul{margin:0;padding-left:1.25rem}.error-container li{margin:.15rem 0}.form-actions{margin-top:1.25rem;display:flex;gap:.75rem}.btn-primary{padding:.6rem 1.5rem;background-color:var(--accent-blue);color:#fff;border:none;border-radius:var(--radius);font-size:.95rem;font-weight:500;cursor:pointer;transition:background-color .15s}.btn-primary:hover{background-color:var(--accent-blue-hover)}.btn-secondary{padding:.5rem 1rem;background-color:transparent;color:var(--accent-blue);border:1px solid var(--accent-blue);border-radius:var(--radius);font-size:.85rem;font-weight:500;cursor:pointer;transition:background-color .15s}.btn-secondary:hover{background-color:#1a73e814}[data-theme=dark] .btn-secondary:hover{background-color:#8ab4f81a}.stats-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(180px,1fr));gap:.75rem}.stat-card{background-color:var(--bg-secondary);border:1px solid var(--border-color);border-radius:var(--radius);padding:.85rem 1rem;display:flex;flex-direction:column;gap:.3rem}.stat-label{font-size:.75rem;font-weight:500;text-transform:uppercase;letter-spacing:.04em;color:var(--text-muted)}.stat-value{font-size:1.15rem;font-weight:600;color:var(--text-primary)}.chart-wrapper{position:relative;height:380px}.table-header-row{display:flex;align-items:center;justify-content:space-between;margin-bottom:1rem}.table-header-row h2{margin-bottom:0}.table-scroll-wrapper{border:1px solid var(--table-border);border-radius:var(--radius);overflow-x:auto}table{width:100%;border-collapse:collapse;font-size:.85rem}thead th{position:sticky;top:0;background-color:var(--table-header-bg);color:var(--text-secondary);font-weight:600;text-align:right;padding:.6rem .85rem;border-bottom:2px solid var(--table-border);z-index:1}thead th:first-child{text-align:center}thead th:nth-child(2){text-align:left}tbody tr:nth-child(2n){background-color:var(--table-stripe)}tbody tr:hover{background-color:#1a73e80d}[data-theme=dark] tbody tr:hover{background-color:#8ab4f812}tbody td{padding:.5rem .85rem;text-align:right;color:var(--text-primary);border-bottom:1px solid var(--table-border);white-space:nowrap}tbody tr:last-child td{border-bottom:none}tbody td:first-child{text-align:center;color:var(--text-muted)}tbody td:nth-child(2){text-align:left;color:var(--text-secondary)}.hide-overpayment .overpayment-col{display:none}@media(max-width:500px){main{padding:1rem}section,#chart-section,#table-section{padding:1rem}.stats-grid{grid-template-columns:1fr 1fr}.chart-wrapper{height:280px}}