body {
    font-family: Segoe UI,Arial,sans-serif;
    background: #eef4ff;
    color: #111;
    margin: 0
}

.dark {
    background: #1c1f26;
    color: #eee
}

.container {
    max-width: 1100px;
    margin: 30px auto;
    padding: 20px
}

.panel {
    background: #fff;
    border-radius: 18px;
    padding: 30px;
    box-shadow: 0 4px 16px rgba(0,0,0,.12);
    text-align: center
}

.dark .panel {
    background: #2c3140;
    color: #eee
}

.grid {
    display: grid;
    grid-template-columns: repeat(auto-fit,minmax(250px,1fr));
    gap: 20px
}

.card {
    background: #f8fbff;
    padding: 24px;
    border-radius: 14px;
    text-decoration: none;
    color: #111
}

.dark .card {
    background: #374056;
    color: #eee
}

button {
    padding: 12px 18px;
    margin: 6px;
    border-radius: 8px;
    border: none
}

.puzzle {
    font-size: 2.3rem;
    font-weight: bold;
    margin: 30px 0;
    color: #0a4a8a
}

.dark .puzzle {
    color: #87b7ff
}

input {
    padding: 12px;
    width: 80%;
    max-width: 500px
}

.stats {
    line-height: 1.8;
    margin: 20px 0
}

.success {
    color: #198754;
    font-weight: bold
}

.error {
    color: #dc3545;
    font-weight: bold
}

.row {
    margin: 6px
}

.tile {
    width: 40px;
    height: 40px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    vertical-align: middle;
    margin: 2px;
    border-radius: 4px;
    font-weight: bold
}

.g {
    background: #2e7d32;
    color: #fff
}

.y {
    background: #c9a227;
    color: #fff
}

.x {
    background: #777;
    color: #fff
}

.e {
    background: #ddd;
    color: #333
}

footer {
    margin-top: 40px
}

a {
    text-decoration: none
}