:root{
    --bg:#f5f6f8;
    --bg2:#ffffff;
    --bg3:#eef0f4;
    --accent:#1d4ed8;
    --accent-light:#3b82f6;
    --accent-dim:rgba(29,78,216,.06);
    --green:#059669;
    --red:#dc2626;
    --orange:#d97706;
    --text:#0f172a;
    --dim:#475569;
    --faint:#94a3b8;
    --border:#e2e8f0;
    --radius:10px;
    --shadow:0 1px 3px rgba(0,0,0,.06),0 1px 2px rgba(0,0,0,.04);
    --shadow-lg:0 10px 30px rgba(0,0,0,.08);
}

*{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth}
body{font-family:'Inter',system-ui,-apple-system,sans-serif;background:var(--bg);color:var(--text);min-height:100vh;-webkit-font-smoothing:antialiased}

/* ═══ NAV ═══ */
.nav{background:var(--bg2);border-bottom:1px solid var(--border);padding:0;position:sticky;top:0;z-index:100;box-shadow:var(--shadow)}
.nav-inner{max-width:1000px;margin:0 auto;padding:0 20px;display:flex;align-items:center;justify-content:space-between;height:56px}
.nav-logo{font-weight:800;font-size:1.15rem;text-decoration:none;color:var(--text);letter-spacing:-.02em}
.nav-links{display:flex;gap:4px;align-items:center}
.nav-links a{color:var(--dim);text-decoration:none;font-size:.84rem;font-weight:500;padding:7px 12px;border-radius:8px;transition:all .15s}
.nav-links a:hover{color:var(--accent);background:var(--accent-dim)}
.btn-nav{background:var(--accent) !important;color:#fff !important;padding:8px 18px !important;border-radius:8px;font-weight:600}
.btn-nav:hover{background:var(--accent-light) !important}

/* ═══ MAIN ═══ */
main{max-width:1000px;margin:0 auto;padding:28px 20px 80px}

/* ═══ CARDS ═══ */
.card{background:var(--bg2);border:1px solid var(--border);border-radius:var(--radius);padding:24px;margin-bottom:14px;box-shadow:var(--shadow)}
.card h2{font-size:1rem;margin-bottom:14px;color:var(--accent);font-weight:700;letter-spacing:-.01em}

/* ═══ BUTTONS ═══ */
.btn{display:inline-flex;align-items:center;justify-content:center;gap:6px;padding:11px 22px;border-radius:var(--radius);font-weight:600;font-size:.9rem;cursor:pointer;border:0;text-decoration:none;font-family:inherit;transition:all .2s;-webkit-tap-highlight-color:transparent}
.btn-blue{background:var(--accent);color:#fff;box-shadow:0 2px 6px rgba(29,78,216,.2)}
.btn-blue:hover{background:var(--accent-light);transform:translateY(-1px);box-shadow:0 4px 12px rgba(29,78,216,.25)}
.btn-outline{background:var(--bg2);border:1.5px solid var(--border);color:var(--dim)}
.btn-outline:hover{border-color:var(--accent);color:var(--accent)}
.btn-sm{padding:7px 14px;font-size:.8rem}
.btn-green{background:var(--green);color:#fff}
.btn-red{background:var(--red);color:#fff}

/* ═══ FORMS ═══ */
input,textarea,select{width:100%;padding:11px 14px;background:var(--bg);border:1.5px solid var(--border);border-radius:8px;font-size:.9rem;color:var(--text);font-family:inherit;outline:none;transition:border-color .2s,box-shadow .2s}
input:focus,textarea:focus,select:focus{border-color:var(--accent);box-shadow:0 0 0 3px rgba(29,78,216,.08)}
label{display:block;font-size:.78rem;color:var(--dim);margin-bottom:5px;font-weight:600;text-transform:uppercase;letter-spacing:.3px}
.form-row{display:grid;grid-template-columns:1fr 1fr;gap:12px;margin-bottom:14px}
.form-full{margin-bottom:14px}

/* ═══ BADGES ═══ */
.badge{display:inline-block;padding:3px 10px;border-radius:20px;font-size:.68rem;font-weight:700;letter-spacing:.3px}
.badge-draft{background:var(--bg3);color:var(--faint)}
.badge-sent{background:rgba(29,78,216,.08);color:var(--accent)}
.badge-paid{background:rgba(5,150,105,.08);color:var(--green)}
.badge-overdue{background:rgba(220,38,38,.08);color:var(--red)}

/* ═══ TABLE ═══ */
table{width:100%;border-collapse:collapse}
th{text-align:left;padding:10px 12px;font-size:.7rem;color:var(--faint);text-transform:uppercase;letter-spacing:.8px;border-bottom:2px solid var(--border);font-weight:700}
td{padding:12px;border-bottom:1px solid var(--border);font-size:.88rem}
tr:hover{background:var(--accent-dim)}

/* ═══ STATS ═══ */
.stats{display:grid;grid-template-columns:repeat(auto-fit,minmax(140px,1fr));gap:10px;margin-bottom:24px}
.stat{background:var(--bg2);border:1px solid var(--border);border-radius:var(--radius);padding:18px 14px;text-align:center;box-shadow:var(--shadow);transition:transform .15s}
.stat:hover{transform:translateY(-2px)}
.stat-num{font-size:1.5rem;font-weight:800;color:var(--accent);letter-spacing:-.02em}
.stat-label{font-size:.68rem;color:var(--faint);text-transform:uppercase;letter-spacing:.8px;margin-top:3px;font-weight:600}

/* ═══ HERO ═══ */
.hero{text-align:center;padding:64px 20px 48px}
.hero h1{font-size:2.4rem;font-weight:800;margin-bottom:14px;letter-spacing:-.03em;line-height:1.15}
.hero h1 span{color:var(--accent);background:linear-gradient(135deg,var(--accent),var(--accent-light));-webkit-background-clip:text;-webkit-text-fill-color:transparent}
.hero p{color:var(--dim);font-size:1.05rem;max-width:480px;margin:0 auto;line-height:1.65}

/* ═══ FEATURES ═══ */
.features{display:grid;grid-template-columns:repeat(auto-fit,minmax(220px,1fr));gap:12px;margin:30px 0}
.feat{background:var(--bg2);border:1px solid var(--border);border-radius:var(--radius);padding:22px;transition:all .2s;box-shadow:var(--shadow)}
.feat:hover{border-color:rgba(29,78,216,.3);transform:translateY(-2px);box-shadow:var(--shadow-lg)}
.feat-icon{font-size:1.8rem;margin-bottom:10px}
.feat h3{font-size:.92rem;margin-bottom:5px;font-weight:700}
.feat p{color:var(--dim);font-size:.82rem;line-height:1.55}

/* ═══ ALERTS ═══ */
.error{background:rgba(220,38,38,.04);border:1px solid rgba(220,38,38,.15);border-radius:var(--radius);padding:12px 16px;color:var(--red);font-size:.88rem;margin-bottom:14px;font-weight:500}
.success{background:rgba(5,150,105,.04);border:1px solid rgba(5,150,105,.15);border-radius:var(--radius);padding:12px 16px;color:var(--green);font-size:.88rem;margin-bottom:14px;font-weight:500}

/* ═══ FOOTER ═══ */
.footer{border-top:1px solid var(--border);padding:20px 0;margin-top:40px;text-align:center}
.footer-inner{font-size:.78rem;color:var(--faint)}
.footer-inner a{color:var(--accent);text-decoration:none}

/* ═══ EMPTY STATE ═══ */
.empty{text-align:center;padding:48px 20px;color:var(--faint)}
.empty-icon{font-size:2.5rem;margin-bottom:12px;opacity:.5}

/* ═══ PRINT ═══ */
@media print{
    .nav,.footer,.no-print{display:none !important}
    body{background:#fff}
    main{padding:0;max-width:100%}
    .card{box-shadow:none;border:1px solid #ddd}
}

/* ═══ MOBILE ═══ */
@media(max-width:768px){
    .hero h1{font-size:1.6rem}
    .hero{padding:40px 16px 32px}
    .form-row{grid-template-columns:1fr}
    .nav-links{gap:2px}
    .nav-links a{padding:6px 8px;font-size:.78rem}
    .stats{grid-template-columns:repeat(2,1fr);gap:8px}
    .stat{padding:14px 10px}
    .stat-num{font-size:1.2rem}
    main{padding:16px 14px 60px}
    table{font-size:.8rem}
    th,td{padding:8px 6px}
    .card{padding:18px 16px}
    .btn{padding:10px 18px;font-size:.85rem}
    .features{grid-template-columns:1fr}
}

@media(max-width:380px){
    .hero h1{font-size:1.4rem}
    .nav-logo{font-size:1rem}
    .stat-num{font-size:1.1rem}
}