:root{
    --primary:#2563eb;
    --primary-hover:#1d4ed8;

    --success:#16a34a;
    --danger:#dc2626;

    --bg:#f4f6f9;
    --card:#ffffff;

    --text:#1f2937;
    --border:#d1d5db;

    --radius:12px;
}

*{
    box-sizing:border-box;
}

body{
    margin:0;
    padding:0;

    font-family:Arial, Helvetica, sans-serif;

    background:var(--bg);
    color:var(--text);
}

.container{
    width:min(1200px,95%);
    margin:0 auto;
}

header{
    background:#fff;
    border-bottom:1px solid var(--border);
    padding:15px 0;
    margin-bottom:20px;
}

header .container{
    display:flex;
    justify-content:space-between;
    align-items:center;
}

header a{
    text-decoration:none;
    color:var(--text);
    font-weight:bold;
}

nav{
    display:flex;
    gap:10px;
    flex-wrap:wrap;
}

nav a{
    padding:8px 14px;
    border-radius:999px;
    background:#eef2ff;
    color:var(--primary);
}

nav a:hover{
    background:#dbeafe;
}

main{
    min-height:70vh;
}

h1{
    margin-top:0;
}

.card{
    background:var(--card);
    border-radius:var(--radius);

    padding:20px;
    margin-bottom:20px;

    box-shadow:
        0 2px 6px rgba(0,0,0,.08);
}

.success{
    background:#dcfce7;
    color:#166534;

    padding:15px;
    margin-bottom:15px;

    border-radius:var(--radius);
}

.error{
    background:#fee2e2;
    color:#991b1b;

    padding:15px;
    margin-bottom:15px;

    border-radius:var(--radius);
}

table{
    width:100%;
    border-collapse:collapse;

    background:#fff;
    border-radius:var(--radius);

    overflow:hidden;
}

th{
    background:#f3f4f6;
}

th,
td{
    padding:12px;
    text-align:left;

    border-bottom:1px solid var(--border);
}

tr:hover{
    background:#f9fafb;
}

form{
    background:#fff;

    padding:20px;
    border-radius:var(--radius);

    box-shadow:
        0 2px 6px rgba(0,0,0,.08);
}

label{
    display:block;

    margin-top:15px;
    margin-bottom:5px;

    font-weight:bold;
}

input,
select,
textarea{
    width:100%;

    padding:10px;

    border:1px solid var(--border);
    border-radius:8px;

    font-size:14px;
}

textarea{
    resize:vertical;
}

button{
    margin-top:20px;

    border:none;

    padding:12px 18px;

    background:var(--primary);
    color:white;

    border-radius:8px;

    cursor:pointer;
}

button:hover{
    background:var(--primary-hover);
}

a{
    color:var(--primary);
}

footer{
    margin-top:40px;

    background:#fff;

    border-top:1px solid var(--border);

    padding:20px 0;

    text-align:center;
}

.stats-grid{
    display:grid;
    grid-template-columns:
        repeat(auto-fit,minmax(250px,1fr));

    gap:20px;
}

.stat-card{
    background:#fff;

    padding:20px;

    border-radius:var(--radius);

    box-shadow:
        0 2px 6px rgba(0,0,0,.08);
}

.stat-number{
    font-size:32px;
    font-weight:bold;

    margin-top:10px;
}