:root {
    --primary: #4f46e5;
    --primary-dark: #4338ca;
    --success: #16a34a;
    --danger: #dc2626;
    --warning: #d97706;
    --bg: #f5f6fb;
    --card-bg: #ffffff;
    --border: #e5e7eb;
    --text: #1f2937;
    --muted: #6b7280;
    --radius: 10px;
}
* { box-sizing: border-box; }
body {
    margin: 0;
    font-family: 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
    background: var(--bg);
    color: var(--text);
}
a { color: var(--primary); text-decoration: none; }
a:hover { text-decoration: underline; }

.topbar {
    background: #fff;
    border-bottom: 1px solid var(--border);
    position: sticky; top: 0; z-index: 10;
}
.topbar-inner {
    max-width: 1100px;
    margin: 0 auto;
    padding: 12px 16px;
    display: flex;
    align-items: center;
    gap: 16px;
    flex-wrap: wrap;
}
.brand { font-weight: 800; font-size: 20px; color: var(--primary); }
.brand-logo { height: 32px; display: block; }
.user-id-badge {
    background: #eef2ff;
    border: 1px solid #c7d2fe;
    border-radius: 999px;
    padding: 4px 12px;
    font-size: 13px;
}
.user-id-badge .label { color: var(--muted); margin-right: 4px; }
.user-id-badge .value { font-weight: 700; color: var(--primary-dark); }

.topnav { margin-left: auto; display: flex; align-items: center; gap: 8px; flex-wrap: wrap; }
.balance-pill { background: #f0fdf4; border: 1px solid #bbf7d0; padding: 4px 10px; border-radius: 999px; font-size: 13px; }
.mailbox-icon { position: relative; display: inline-flex; align-items: center; justify-content: center; width: 48px; height: 48px; border-radius: 999px; background: #f1f5f9; font-size: 26px; text-decoration: none; color: inherit; }
.mailbox-icon:hover { background: #e2e8f0; }
.mailbox-badge { position: absolute; top: -6px; right: -6px; background: #ef4444; color: #fff; font-size: 11px; font-weight: 700; line-height: 1; padding: 4px 6px; border-radius: 999px; min-width: 18px; text-align: center; }
.message-item { display: block; padding: 14px 16px; border: 1px solid #e5e7eb; border-radius: 8px; margin-bottom: 10px; text-decoration: none; color: inherit; }
.message-item.unread { background: #eff6ff; border-color: #bfdbfe; }
.message-item .msg-title { font-weight: 700; margin-bottom: 4px; }
.message-item .msg-meta { font-size: 12px; color: var(--muted); }
.inline-approve-form { display: inline-flex; gap: 4px; align-items: center; margin-right: 6px; }
.user-name { font-size: 14px; color: var(--muted); margin-left: 4px; }

.page-wrap { max-width: 1100px; margin: 24px auto; padding: 0 16px 60px; }

.btn {
    display: inline-block;
    padding: 9px 16px;
    border-radius: 8px;
    border: 1px solid transparent;
    font-size: 14px;
    font-weight: 600;
    cursor: pointer;
    background: #eee;
    color: #333;
}
.btn-sm { padding: 5px 10px; font-size: 12px; }
.btn-lg { padding: 12px 22px; font-size: 16px; }
.btn-block { display: block; width: 100%; text-align: center; }
.btn-primary { background: var(--primary); color: #fff; }
.btn-primary:hover { background: var(--primary-dark); }
.btn-success { background: var(--success); color: #fff; }
.btn-warning { background: var(--warning); color: #fff; }
.btn-danger { background: var(--danger); color: #fff; }
.btn-outline { background: #fff; border: 1px solid var(--border); color: var(--text); }
.btn-google { background: #fff; border: 1px solid var(--border); display: flex; align-items: center; justify-content: center; gap: 8px; }
.btn:hover { opacity: 0.92; text-decoration: none; }

.auth-box, .hub-card {
    background: var(--card-bg);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 24px;
    margin-bottom: 20px;
    max-width: 480px;
}
.hub-card { max-width: none; }
.auth-box h1, .hub-card h1, .hub-card h2 { margin-top: 0; }

.form label { display: block; margin-bottom: 14px; font-size: 14px; font-weight: 600; color: var(--text); }
.form input[type=text], .form input[type=email], .form input[type=password],
.form input[type=number], .form select, .form input[type=file] {
    display: block; width: 100%; margin-top: 6px; padding: 10px 12px;
    border: 1px solid var(--border); border-radius: 8px; font-size: 14px;
}
.form-inline { display: flex; gap: 8px; align-items: center; }
.form-inline input { padding: 9px 12px; border: 1px solid var(--border); border-radius: 8px; flex: 1; }

.divider { text-align: center; color: var(--muted); margin: 16px 0; font-size: 13px; }
.muted { color: var(--muted); }
.small { font-size: 12px; }
.center { text-align: center; }

.alert { padding: 12px 16px; border-radius: 8px; margin-bottom: 16px; font-size: 14px; }
.alert-success { background: #f0fdf4; color: #166534; border: 1px solid #bbf7d0; }
.alert-danger { background: #fef2f2; color: #991b1b; border: 1px solid #fecaca; }
.alert-info { background: #eff6ff; color: #1e40af; border: 1px solid #bfdbfe; }

.trade-hub { display: grid; gap: 20px; }
.hub-actions { display: flex; gap: 12px; flex-wrap: wrap; margin: 16px 0; }
.join-box { background: #f9fafb; border: 1px dashed var(--border); padding: 16px; border-radius: 8px; margin-top: 10px; }

.table { width: 100%; border-collapse: collapse; font-size: 14px; }
.table th, .table td { text-align: left; padding: 10px 8px; border-bottom: 1px solid var(--border); }
.table th { color: var(--muted); font-weight: 600; font-size: 12px; text-transform: uppercase; }

.badge { display: inline-block; padding: 3px 10px; border-radius: 999px; font-size: 12px; font-weight: 700; background: #eee; }
.badge-waiting, .badge-pending { background: #fef9c3; color: #854d0e; }
.badge-offering { background: #dbeafe; color: #1e40af; }
.badge-confirmed, .badge-approved { background: #dcfce7; color: #166534; }
.badge-admin_review { background: #fde68a; color: #78350f; }
.badge-completed { background: #dcfce7; color: #166534; }
.badge-cancelled, .badge-rejected { background: #fee2e2; color: #991b1b; }

.trade-room { max-width: 900px; }
.trade-room-head { display: flex; justify-content: space-between; align-items: center; margin-bottom: 16px; flex-wrap: wrap; gap: 8px; }
.big-code { font-size: 18px; background: #f3f4f6; padding: 4px 10px; border-radius: 6px; }

.trade-vs { display: flex; align-items: center; justify-content: center; gap: 20px; margin: 20px 0; font-size: 18px; font-weight: 700; }
.trade-vs .vs-x { color: var(--primary); font-size: 24px; }
.trade-vs small { font-weight: 400; color: var(--muted); font-size: 13px; }

.trade-columns { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; margin: 20px 0; }
.trade-col { background: #fff; border: 1px solid var(--border); border-radius: var(--radius); padding: 16px; }
.trade-col.is-mine { border-color: var(--primary); box-shadow: 0 0 0 2px #e0e7ff; }
.tag-you { color: var(--primary); font-size: 12px; }
.type-switch { display: flex; gap: 16px; margin: 10px 0; font-size: 14px; font-weight: 400; }
.offer-amount { font-size: 22px; font-weight: 800; color: var(--primary-dark); }
.item-list { list-style: none; padding: 0; margin: 10px 0; }
.item-list li { padding: 6px 0; border-bottom: 1px dashed var(--border); font-size: 14px; }
.offer-confirm { margin-top: 14px; }
.link-danger { background: none; border: none; color: var(--danger); cursor: pointer; font-size: 12px; text-decoration: underline; padding: 0; }

.two-col { display: grid; grid-template-columns: 1.2fr 1fr; gap: 20px; align-items: start; }
.tabs { display: flex; gap: 8px; margin-bottom: 16px; }
.tab-btn { padding: 8px 14px; border-radius: 8px; border: 1px solid var(--border); background: #fff; cursor: pointer; font-size: 13px; font-weight: 600; }
.tab-btn.active { background: var(--primary); color: #fff; border-color: var(--primary); }
.bank-info { background: #f9fafb; border: 1px dashed var(--border); padding: 12px; border-radius: 8px; font-size: 14px; margin: 10px 0; }

.admin-stats { display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px; margin-top: 20px; }
.settings-form .hub-card { max-width: 640px; }
.settings-form label { margin-bottom: 12px; }
.logo-preview { display: flex; align-items: center; gap: 12px; margin-bottom: 12px; }
.inline-checkbox { display: inline-flex !important; align-items: center; gap: 6px; font-weight: 400 !important; margin: 0 !important; }
.inline-checkbox input { width: auto !important; margin: 0 !important; }
.divider-line { border: none; border-top: 1px dashed var(--border); margin: 16px 0; }
.stat-card { background: #fff; border: 1px solid var(--border); border-radius: var(--radius); padding: 20px; text-align: center; }
.stat-card a { color: inherit; }
.stat-num { font-size: 32px; font-weight: 800; color: var(--primary); }
.stat-label { color: var(--muted); font-size: 13px; margin-top: 4px; }

.site-footer { text-align: center; color: var(--muted); font-size: 13px; padding: 20px; }

@media (max-width: 700px) {
    .trade-columns, .two-col, .admin-stats { grid-template-columns: 1fr; }
}