:root{--color-bg: #fafafa;--color-surface: #ffffff;--color-text: #1a1a1a;--color-muted: #6b7280;--color-border: #e5e7eb;--color-accent: #111827;--color-green: #059669;--color-red: #dc2626;--radius: .5rem;--max-width: 960px}*{margin:0;padding:0;box-sizing:border-box}body{font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Helvetica Neue,Arial,sans-serif;background:var(--color-bg);color:var(--color-text);line-height:1.6}.landing-page{max-width:720px;margin:0 auto;padding:0 1.5rem}.hero{display:flex;flex-direction:column;align-items:center;text-align:center;padding:6rem 0 4rem}.hero-title{font-size:3.5rem;font-weight:800;letter-spacing:-.03em;margin-bottom:.75rem}.hero-tagline{font-size:1.375rem;color:var(--color-muted);margin-bottom:1.5rem}.hero-body{color:var(--color-muted);max-width:32rem;margin-bottom:2.5rem;line-height:1.7}.features{padding:3rem 0}.features-grid{display:grid;grid-template-columns:1fr 1fr;gap:1.5rem}@media(max-width:600px){.features-grid{grid-template-columns:1fr}}.feature-card{background:var(--color-surface);border:1px solid var(--color-border);border-radius:var(--radius);padding:1.5rem}.feature-title{font-size:1rem;font-weight:600;margin-bottom:.375rem}.feature-desc{font-size:.875rem;color:var(--color-muted);line-height:1.6}.principles{padding:3rem 0}.section-title{font-size:1.5rem;font-weight:700;text-align:center;margin-bottom:2rem;letter-spacing:-.01em}.principles-grid{display:grid;grid-template-columns:1fr 1fr 1fr;gap:1.5rem}@media(max-width:600px){.principles-grid{grid-template-columns:1fr}}.principle h4{font-size:.9375rem;font-weight:600;margin-bottom:.375rem}.principle p{font-size:.8125rem;color:var(--color-muted);line-height:1.6}.landing-footer{padding:3rem 0;text-align:center;border-top:1px solid var(--color-border)}.footer-text{font-size:.8125rem;color:var(--color-muted);font-style:italic}.btn{padding:.625rem 1.5rem;font-size:.9375rem;border-radius:var(--radius);border:1px solid transparent;cursor:pointer;font-weight:500;transition:opacity .15s}.btn:hover{opacity:.85}.btn:disabled{opacity:.5;cursor:default}.btn-primary{background:var(--color-accent);color:#fff}.btn-lg{padding:.875rem 2.5rem;font-size:1.0625rem}.app-layout{max-width:var(--max-width);margin:0 auto;padding:0 1.5rem}.app-header{display:flex;justify-content:space-between;align-items:center;padding:1rem 0;border-bottom:1px solid var(--color-border);margin-bottom:2rem}.app-header-left{display:flex;align-items:center;gap:2rem}.app-logo{font-size:1.25rem;font-weight:700;letter-spacing:-.02em}.app-nav{display:flex;gap:.25rem}.nav-link{padding:.375rem .75rem;border-radius:var(--radius);text-decoration:none;color:var(--color-muted);font-size:.875rem;font-weight:500;transition:background .15s,color .15s}.nav-link:hover{background:var(--color-border);color:var(--color-text)}.nav-link-active,.nav-link-active:hover{background:var(--color-accent);color:#fff}.app-main{padding-bottom:3rem}.stat-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(180px,1fr));gap:1rem;margin-bottom:2rem}.stat-card{background:var(--color-surface);border:1px solid var(--color-border);border-radius:var(--radius);padding:1.25rem}.stat-label{font-size:.8125rem;color:var(--color-muted);margin-bottom:.25rem}.stat-value{font-size:1.5rem;font-weight:600}.data-table{width:100%;border-collapse:collapse;background:var(--color-surface);border:1px solid var(--color-border);border-radius:var(--radius);overflow:hidden;font-size:.875rem}.data-table th{text-align:left;padding:.75rem 1rem;font-weight:600;font-size:.75rem;text-transform:uppercase;letter-spacing:.05em;color:var(--color-muted);border-bottom:1px solid var(--color-border);background:var(--color-bg)}.data-table td{padding:.625rem 1rem;border-bottom:1px solid var(--color-border)}.data-table tbody tr:last-child td{border-bottom:none}.data-table tbody tr:hover{background:var(--color-bg)}.income{color:var(--color-green)}.expense{color:var(--color-red)}.month-input{padding:.375rem .75rem;border:1px solid var(--color-border);border-radius:var(--radius);font-size:.875rem;background:var(--color-surface)}