/* 多平台封面尺寸生成 —— 复用 life-calc 变量与基础类，仅定义专有样式 */
#app .cov-drop {
    border: 2px dashed var(--border);
    border-radius: var(--radius);
    background: #fafbff;
    padding: 28px 16px;
    text-align: center;
    cursor: pointer;
    transition: border-color var(--transition), background var(--transition);
}
#app .cov-drop:hover { border-color: var(--primary); background: var(--primary-light); }
#app .cov-drop-inner svg { color: var(--primary); }
#app .cov-drop-title { font-size: 1rem; font-weight: 600; margin: 8px 0 4px; }
#app .cov-drop-sub { font-size: 0.82rem; color: var(--text-secondary); }
#app .cov-drop .badge { margin-top: 12px; }

#app .cov-msg {
    margin-top: 12px;
    padding: 8px 12px;
    border-radius: 8px;
    font-size: 0.85rem;
    background: var(--danger-bg);
    color: var(--danger);
}

#app .cov-bg-row {
    display: flex;
    align-items: center;
    gap: 10px;
    margin-top: 14px;
    flex-wrap: wrap;
}
#app .cov-bg-row > label { font-size: 0.85rem; color: var(--text-secondary); font-weight: 500; }
#app .cov-bg-btns { display: inline-flex; gap: 6px; }
#app .cov-bg {
    width: 26px; height: 26px;
    border-radius: 7px;
    border: 2px solid var(--border);
    cursor: pointer;
    padding: 0;
    transition: transform var(--transition), border-color var(--transition);
}
#app .cov-bg:hover { transform: scale(1.08); }
#app .cov-bg.active { border-color: var(--primary); box-shadow: 0 0 0 2px var(--primary-light); }
#app .cov-bg-row input[type="color"] { width: 34px; height: 28px; border: 1px solid var(--border); border-radius: 7px; background: #fff; cursor: pointer; padding: 2px; }

#app .cov-body { display: grid; grid-template-columns: 1fr 360px; gap: 18px; align-items: start; }
#app .cov-stage-card { position: sticky; top: 16px; }
#app .cov-stage {
    position: relative;
    background:
        linear-gradient(45deg, #eee 25%, transparent 25%) 0 0 / 18px 18px,
        linear-gradient(-45deg, #eee 25%, transparent 25%) 0 0 / 18px 18px,
        linear-gradient(45deg, #fff 25%, transparent 25%) 9px 9px / 18px 18px,
        linear-gradient(-45deg, #fff 25%, transparent 25%) 9px 9px / 18px 18px;
    background-color: #f3f3f3;
    border-radius: 10px;
    min-height: 240px;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
    padding: 10px;
}
#app .cov-stage canvas {
    max-width: 100%;
    max-height: 62vh;
    border-radius: 4px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.12);
    display: block;
}
#app .cov-safe {
    position: absolute;
    border: 2px dashed rgba(239,68,68,0.7);
    pointer-events: none;
}
#app .cov-safe-label {
    position: absolute; top: 2px; left: 4px;
    font-size: 0.7rem; color: #ef4444; background: rgba(255,255,255,0.85);
    padding: 0 4px; border-radius: 3px;
}
#app .cov-stage-tip { margin-top: 10px; font-size: 0.85rem; color: var(--text-secondary); text-align: center; }
#app .cov-actions { display: flex; gap: 10px; margin-top: 14px; flex-wrap: wrap; }
#app .cov-actions .btn { flex: 1; justify-content: center; }

#app .cov-chips { display: flex; flex-wrap: wrap; gap: 8px; }
#app .cov-chip {
    border: 1.5px solid var(--border);
    background: #fff;
    border-radius: 9px;
    padding: 8px 10px;
    font-size: 0.82rem;
    cursor: pointer;
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    gap: 2px;
    transition: all var(--transition);
    font-family: inherit;
    color: var(--text);
}
#app .cov-chip small { font-size: 0.7rem; color: var(--text-secondary); }
#app .cov-chip:hover { border-color: var(--primary); }
#app .cov-chip.active { border-color: var(--primary); background: var(--primary-light); color: var(--primary); font-weight: 600; }
#app .cov-chip.active small { color: var(--primary); }

#app .cov-custom { margin-top: 12px; }
#app .cov-custom > label { font-size: 0.82rem; color: var(--text-secondary); font-weight: 500; }
#app .cov-row { display: flex; align-items: center; gap: 8px; margin-top: 6px; }
#app .cov-row .text-input { text-align: center; }
#app .cov-x { color: var(--text-secondary); font-weight: 600; }

#app .cov-mode-desc { font-size: 0.8rem; color: var(--text-secondary); margin: 10px 0; line-height: 1.6; }
#app .cov-bg-card { border-top: 1px dashed var(--border); padding-top: 12px; margin-top: 4px; display: none; }
#app .cov-bg-card.show { display: block; }
#app .cov-bg-card > label { font-size: 0.82rem; color: var(--text-secondary); font-weight: 500; display: block; margin-bottom: 6px; }
#app .cov-bg-card .cov-bg-btns { display: inline-flex; gap: 6px; vertical-align: middle; margin-right: 8px; }

#app .cov-check {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 0.85rem;
    color: var(--text);
    margin-bottom: 10px;
    cursor: pointer;
}
#app .cov-check input { accent-color: var(--primary); width: 16px; height: 16px; }
#app .cov-stat { margin-top: 12px; font-size: 0.8rem; color: var(--text-secondary); }

#app .cov-help p { font-size: 0.85rem; line-height: 1.75; margin-bottom: 8px; }
#app .cov-help b { color: var(--primary); }

@media (max-width: 900px) {
    #app .cov-body { grid-template-columns: 1fr; }
    #app .cov-stage-card { position: static; }
}
@media (max-width: 520px) {
    #app .cov-actions .btn { flex: 1 1 100%; }
    #app .cov-stage canvas { max-height: 46vh; }
}