/* ── Reset & Base ────────────────────────────────────────────── */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }
[hidden] { display: none !important; }

body {
    font-family: 'Inter', sans-serif;
    color: #fff;
    background: radial-gradient(ellipse at center, #1a237e 0%, #0d1442 50%, #000051 100%);
    min-height: 100vh;
    line-height: 1.5;
}

.container { max-width: 1200px; margin: 0 auto; padding: 24px 16px; }

/* ── Header ─────────────────────────────────────────────────── */
header { text-align: center; margin-bottom: 28px; }

header h1 {
    font-family: 'Oswald', sans-serif;
    font-size: 2.8rem;
    font-weight: 700;
    color: #FFD700;
    text-transform: uppercase;
    letter-spacing: 2px;
    text-shadow: 3px 3px 6px rgba(0,0,0,.7), 0 0 16px rgba(255,215,0,.25);
}

.subtitle {
    font-size: 1rem;
    color: rgba(255,255,255,.7);
    margin-top: 4px;
    letter-spacing: .5px;
}

/* ── Main Panel ─────────────────────────────────────────────── */
main {
    background: linear-gradient(145deg, #0d1442, #1a237e 60%, #283593);
    border: 3px solid #FFD700;
    border-radius: 16px;
    padding: 32px;
    box-shadow: 0 20px 50px rgba(0,0,0,.4), 0 0 30px rgba(255,215,0,.08);
    margin-bottom: 28px;
}

/* ── Search Box ─────────────────────────────────────────────── */
.search-box {
    display: flex;
    gap: 10px;
    margin-bottom: 16px;
}

#topicInput {
    flex: 1;
    padding: 14px 18px;
    border: 2px solid #FFD700;
    border-radius: 10px;
    font-size: 1.05rem;
    font-family: 'Oswald', sans-serif;
    font-weight: 500;
    background: rgba(255,255,255,.06);
    color: #fff;
    letter-spacing: .5px;
    text-transform: uppercase;
    transition: border-color .2s, box-shadow .2s;
}
#topicInput::placeholder { color: rgba(255,255,255,.45); text-transform: none; }
#topicInput:focus {
    outline: none;
    border-color: #FFA500;
    box-shadow: 0 0 0 3px rgba(255,215,0,.25);
}

#searchButton {
    padding: 14px 28px;
    background: linear-gradient(135deg, #FFD700, #FFA500);
    color: #000080;
    border: none;
    border-radius: 10px;
    font-family: 'Oswald', sans-serif;
    font-size: 1.05rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: .5px;
    cursor: pointer;
    min-width: 110px;
    transition: transform .15s, box-shadow .15s;
    box-shadow: 0 4px 14px rgba(255,215,0,.35);
}
#searchButton:hover { transform: translateY(-1px); box-shadow: 0 6px 18px rgba(255,215,0,.45); }
#searchButton:disabled { opacity: .6; cursor: not-allowed; transform: none; }

.btn-spinner[hidden] { display: none; }
.btn-spinner {
    display: inline-block;
    width: 16px; height: 16px;
    border: 2px solid rgba(0,0,128,.3);
    border-top-color: #000080;
    border-radius: 50%;
    animation: spin .6s linear infinite;
    vertical-align: middle;
}
@keyframes spin { to { transform: rotate(360deg); } }

/* ── Filters ────────────────────────────────────────────────── */
.filters {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
    padding: 14px 18px;
    background: rgba(255,215,0,.06);
    border: 1px solid rgba(255,215,0,.2);
    border-radius: 10px;
    margin-bottom: 20px;
}

.filter-group {
    display: flex;
    flex-direction: column;
    gap: 4px;
    min-width: 100px;
    flex: 1;
}
.filter-group:last-child {
    flex: 0 0 auto;
    min-width: auto;
}
.filter-group label {
    font-size: .75rem;
    font-weight: 600;
    color: #FFD700;
    text-transform: uppercase;
    letter-spacing: .5px;
}
.filter-group select,
.filter-group input[type="number"] {
    padding: 8px 10px;
    border: 1px solid rgba(255,215,0,.35);
    border-radius: 6px;
    background: rgba(255,255,255,.06);
    color: #fff;
    font-family: 'Inter', sans-serif;
    font-size: .85rem;
}
.filter-group select option { background: #0d1442; color: #fff; }
.filter-group input[type="number"] { width: 100%; }

.view-toggle {
    display: flex;
    border: 1px solid rgba(255,215,0,.35);
    border-radius: 6px;
    overflow: hidden;
    height: 36px;
}
.toggle-btn {
    padding: 8px 14px;
    border: none;
    background: rgba(255,255,255,.06);
    color: rgba(255,255,255,.6);
    font-family: 'Inter', sans-serif;
    font-size: .85rem;
    font-weight: 600;
    cursor: pointer;
    transition: background .2s, color .2s;
}
.toggle-btn + .toggle-btn {
    border-left: 1px solid rgba(255,215,0,.35);
}
.toggle-btn.active {
    background: rgba(255,215,0,.2);
    color: #FFD700;
}
.toggle-btn:hover:not(.active) {
    background: rgba(255,255,255,.1);
}

/* ── Status Bar ─────────────────────────────────────────────── */
.status-bar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 10px 0;
    margin-bottom: 14px;
    border-bottom: 2px solid rgba(255,215,0,.3);
    font-size: .9rem;
    color: rgba(255,255,255,.8);
}

.export-btn {
    padding: 6px 14px;
    background: rgba(255,215,0,.15);
    border: 1px solid rgba(255,215,0,.4);
    border-radius: 6px;
    color: #FFD700;
    font-size: .8rem;
    font-weight: 600;
    cursor: pointer;
    transition: background .2s;
}
.export-btn:hover { background: rgba(255,215,0,.25); }

/* ── Card Grid ──────────────────────────────────────────────── */
.results-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 16px;
}

.card {
    background: linear-gradient(145deg, #060CE9, #0033CC);
    border: 2px solid #FFD700;
    border-radius: 14px;
    padding: 20px;
    display: flex;
    flex-direction: column;
    gap: 12px;
    transition: transform .2s, box-shadow .2s;
    box-shadow: 0 8px 24px rgba(0,0,0,.35);
}
.card:hover {
    transform: translateY(-3px);
    box-shadow: 0 12px 30px rgba(0,0,0,.45);
    border-color: #FFA500;
}

.card-title {
    font-family: 'Oswald', sans-serif;
    font-size: 1.25rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: .4px;
    line-height: 1.25;
    color: #fff;
    text-shadow: 1px 1px 3px rgba(0,0,0,.5);
}

.badge {
    display: inline-block;
    padding: 2px 8px;
    border-radius: 4px;
    font-size: .7rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: .5px;
    align-self: flex-start;
}
.badge-strong  { background: #FFD700; color: #000080; }
.badge-name    { background: rgba(255,215,0,.2); color: #FFD700; border: 1px solid rgba(255,215,0,.4); }
.badge-related { background: rgba(255,255,255,.1); color: rgba(255,255,255,.7); border: 1px solid rgba(255,255,255,.2); }
.badge-weak    { background: rgba(255,255,255,.05); color: rgba(255,255,255,.5); border: 1px solid rgba(255,255,255,.1); }

.card-stats {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 8px;
}

.card-stat {
    display: flex;
    justify-content: space-between;
    padding: 6px 10px;
    background: rgba(255,215,0,.06);
    border: 1px solid rgba(255,215,0,.2);
    border-radius: 6px;
    font-size: .8rem;
}
.card-stat .label { color: rgba(255,255,255,.65); }
.card-stat .val   { color: #FFD700; font-weight: 600; }

/* Difficulty bar */
.diff-bar {
    display: flex;
    height: 8px;
    border-radius: 4px;
    overflow: hidden;
    background: rgba(255,255,255,.1);
}
.seg-easy   { background: #4CAF50; }
.seg-medium { background: #FF9800; }
.seg-hard   { background: #f44336; }

.diff-legend {
    display: flex;
    gap: 10px;
    font-size: .7rem;
    color: rgba(255,255,255,.55);
}
.diff-legend span::before {
    content: '';
    display: inline-block;
    width: 8px; height: 8px;
    border-radius: 2px;
    margin-right: 3px;
    vertical-align: middle;
}
.diff-legend .leg-easy::before   { background: #4CAF50; }
.diff-legend .leg-med::before    { background: #FF9800; }
.diff-legend .leg-hard::before   { background: #f44336; }

/* ── Table View ─────────────────────────────────────────────── */
.results-table-wrap { overflow-x: auto; }

.results-table {
    width: 100%;
    border-collapse: collapse;
    font-size: .85rem;
}
.results-table th {
    text-align: left;
    padding: 10px 12px;
    border-bottom: 2px solid #FFD700;
    color: #FFD700;
    font-family: 'Oswald', sans-serif;
    font-weight: 600;
    text-transform: uppercase;
    font-size: .75rem;
    letter-spacing: .5px;
}
.results-table td {
    padding: 8px 12px;
    border-bottom: 1px solid rgba(255,215,0,.1);
    vertical-align: middle;
}
.results-table tbody tr:hover { background: rgba(255,215,0,.05); }

.table-diff-bar {
    display: flex;
    height: 6px;
    width: 80px;
    border-radius: 3px;
    overflow: hidden;
    background: rgba(255,255,255,.1);
}
.table-diff-bar > div {
    flex: none;
}

/* ── Pagination ─────────────────────────────────────────────── */
.pagination {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 16px;
    margin-top: 20px;
}

.page-btn {
    padding: 8px 16px;
    background: rgba(255,215,0,.1);
    border: 1px solid rgba(255,215,0,.3);
    border-radius: 6px;
    color: #FFD700;
    font-weight: 600;
    font-size: .85rem;
    cursor: pointer;
    transition: background .2s;
}
.page-btn:hover:not(:disabled) { background: rgba(255,215,0,.2); }
.page-btn:disabled { opacity: .35; cursor: default; }

.page-info { font-size: .85rem; color: rgba(255,255,255,.6); }

/* ── Messages ───────────────────────────────────────────────── */
.message {
    text-align: center;
    padding: 24px;
    border-radius: 10px;
    margin-top: 16px;
    font-size: .95rem;
}
.message.loading { color: #FFD700; }
.message.error   { color: #ff6b6b; background: rgba(220,53,69,.1); border: 1px solid rgba(220,53,69,.3); }

/* ── Footer ─────────────────────────────────────────────────── */
footer {
    background: linear-gradient(145deg, #0d1442, #1a237e 60%, #283593);
    border: 3px solid #FFD700;
    border-radius: 16px;
    padding: 24px 32px;
    box-shadow: 0 12px 30px rgba(0,0,0,.3);
}

.stats-row {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
    gap: 14px;
    margin-bottom: 14px;
}

.stat-box {
    text-align: center;
    padding: 10px;
    background: rgba(255,215,0,.06);
    border: 1px solid rgba(255,215,0,.2);
    border-radius: 8px;
}
.stat-label {
    display: block;
    font-size: .7rem;
    text-transform: uppercase;
    letter-spacing: .5px;
    color: rgba(255,255,255,.6);
    margin-bottom: 4px;
}
.stat-val {
    display: block;
    font-size: 1.15rem;
    font-weight: 700;
    color: #FFD700;
}

.disclaimer {
    text-align: center;
    font-size: .8rem;
    color: rgba(255,255,255,.45);
    margin-top: 10px;
}

/* ── Responsive ─────────────────────────────────────────────── */
@media (max-width: 768px) {
    header h1 { font-size: 2rem; }
    main { padding: 20px 16px; }
    .search-box { flex-direction: column; }
    .filters { flex-direction: column; }
    .results-grid { grid-template-columns: 1fr; }
    .card-stats { grid-template-columns: 1fr; }
    .stats-row { grid-template-columns: repeat(2, 1fr); }
}