/* ===== 数位顺序表练习 ===== */
#pvApp .pv-hero { text-align: center; padding: 12px 10px 0; }
#pvApp .pv-hero h1 { font-size: 30px; font-weight: 800; color: var(--c-text); margin-bottom: 10px; }
#pvApp .pv-hero p { font-size: 15px; color: var(--c-text-sub); line-height: 1.7; }

#pvApp .pv-bar { display: flex; flex-wrap: wrap; gap: 8px; justify-content: center; margin: 18px 0; }
#pvApp .pv-tab {
    border: 2px solid var(--c-primary); background: transparent; color: var(--c-primary);
    border-radius: 999px; padding: 8px 16px; font-size: 14px; font-weight: 700;
    cursor: pointer; transition: background .15s, color .15s;
}
#pvApp .pv-tab.is-on { background: var(--c-primary); color: #fff; }
#pvApp .pv-tab.gray { border-color: var(--c-border); color: var(--c-text-sub); }
#pvApp .pv-tab.gray.is-on { background: var(--c-text-sub); color: #fff; border-color: var(--c-text-sub); }

#pvApp .pv-panel {
    max-width: 760px; margin: 0 auto; background: var(--c-surface);
    border: 1px solid var(--c-border); border-radius: var(--radius-md);
    padding: 20px 16px; box-shadow: var(--shadow-md);
}

/* 数位顺序表 */
#pvApp .pv-table-wrap { overflow-x: auto; padding-bottom: 4px; }
#pvApp .pv-table { display: flex; min-width: 460px; justify-content: center; }
#pvApp .pv-group { display: flex; }
#pvApp .pv-group + .pv-group { margin-left: 8px; padding-left: 8px; border-left: 2px dashed var(--c-border); }
#pvApp .pv-cell {
    width: 46px; border: 1px solid var(--c-border); border-right: none;
    display: flex; flex-direction: column; align-items: center; justify-content: center;
    padding: 7px 0; cursor: pointer; transition: background .15s;
}
#pvApp .pv-cell:last-child { border-right: 1px solid var(--c-border); }
#pvApp .pv-cell:hover { background: var(--c-surface-soft); }
#pvApp .pv-cell.is-sel { background: var(--c-primary-soft); }
#pvApp .pv-pname { font-size: 12px; font-weight: 800; color: var(--c-primary); line-height: 1.4; white-space: nowrap; }
#pvApp .pv-digit { font-size: 21px; font-weight: 800; color: var(--c-text); line-height: 1.5; }
#pvApp .pv-digit.empty { color: var(--c-text-muted); font-weight: 600; }
#pvApp .pv-glabel { font-size: 11px; font-weight: 700; color: var(--c-text-muted); text-align: center; margin-top: 6px; }

#pvApp .pv-pick {
    margin-top: 12px; text-align: center; font-size: 15px; font-weight: 700;
    color: var(--c-primary); min-height: 22px;
}

#pvApp .pv-q {
    margin-top: 18px; font-size: 18px; font-weight: 800; color: var(--c-text);
    text-align: center; line-height: 1.7;
}
#pvApp .pv-q b { color: var(--c-primary); }

#pvApp .pv-opts { display: grid; grid-template-columns: repeat(2, 1fr); gap: 10px; margin-top: 16px; }
#pvApp .pv-opt {
    border: 2px solid var(--c-border); background: var(--c-surface-soft); color: var(--c-text);
    border-radius: 14px; padding: 13px 10px; font-size: 16px; font-weight: 700; cursor: pointer; transition: .15s;
}
#pvApp .pv-opt:hover { border-color: var(--c-primary); color: var(--c-primary); }
#pvApp .pv-opt.ok { border-color: var(--c-accent-green); background: var(--c-primary-soft); color: var(--c-primary); }
#pvApp .pv-opt.bad { border-color: #e03131; color: #e03131; }

#pvApp .pv-fill { text-align: center; margin-top: 16px; display: none; }
#pvApp .pv-fill.show { display: block; }
#pvApp .pv-in {
    width: 190px; height: 60px; border: 2px solid var(--c-primary); border-radius: 14px;
    background: var(--c-surface-soft); color: var(--c-primary);
    font-size: 26px; font-weight: 800; text-align: center; outline: none; letter-spacing: 1px;
}

#pvApp .pv-msg { text-align: center; font-size: 17px; font-weight: 800; min-height: 26px; margin-top: 14px; color: var(--c-text); }
#pvApp .pv-msg.ok { color: var(--c-primary); }
#pvApp .pv-msg.bad { color: #e03131; }

#pvApp .pv-ctrl { display: flex; flex-wrap: wrap; gap: 10px; justify-content: center; margin-top: 18px; }
#pvApp .pv-btn {
    border: none; border-radius: 999px; padding: 12px 20px; font-size: 15px; font-weight: 700;
    color: #fff; cursor: pointer; background: linear-gradient(135deg, var(--c-primary), var(--c-accent-cyan));
    box-shadow: var(--shadow-md);
}
#pvApp .pv-btn.gray { background: var(--c-surface-2); color: var(--c-text); box-shadow: none; border: 1px solid var(--c-border); }
#pvApp .pv-btn:disabled { opacity: .5; cursor: default; }

#pvApp .pv-stat {
    max-width: 760px; margin: 18px auto 0; background: var(--c-surface);
    border: 1px solid var(--c-border); border-radius: var(--radius-md);
    padding: 14px 18px; box-shadow: var(--shadow-md); text-align: center;
    font-size: 14px; line-height: 1.9; color: var(--c-text-sub);
}
#pvApp .pv-stat b { color: var(--c-primary); font-size: 18px; }

#pvApp .pv-ai, #pvApp .pv-info { max-width: 760px; margin: 30px auto 0; }
#pvApp .pv-ai h2, #pvApp .pv-info h2 { font-size: 20px; font-weight: 800; color: var(--c-text); margin-bottom: 10px; }
#pvApp .pv-ai p { font-size: 14px; color: var(--c-text-sub); line-height: 1.8; margin-bottom: 14px; }
#pvApp .pv-ai-row { display: flex; gap: 10px; flex-wrap: wrap; }
#pvApp .pv-out {
    margin-top: 14px; background: var(--c-surface-soft); border: 1px solid var(--c-border);
    border-radius: var(--radius-sm); padding: 16px 18px;
    font-size: 15px; line-height: 1.85; color: var(--c-text); white-space: pre-wrap;
}
#pvApp .pv-info ul { list-style: disc; padding-left: 22px; margin-bottom: 24px; }
#pvApp .pv-info li { font-size: 14px; line-height: 1.9; color: var(--c-text-sub); margin-bottom: 8px; }
#pvApp .pv-info li b { color: var(--c-text); }

@media (max-width: 560px) {
    #pvApp .pv-hero h1 { font-size: 24px; }
    #pvApp .pv-opts { grid-template-columns: 1fr; }
}