/* ===== 设计工具页专属样式（复用 style.css 的变量与视觉语言） ===== */

.design-section { padding-top: 1rem; }

/* 主 Tab */
.calc-tabs {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-bottom: 1.5rem;
}
.calc-tab {
    padding: 0.7rem 1.25rem;
    border: 1px solid var(--border);
    background: var(--bg-card);
    color: var(--text-muted);
    font-size: 0.95rem;
    font-weight: 600;
    border-radius: 999px;
    cursor: pointer;
    transition: var(--transition);
    font-family: inherit;
}
.calc-tab:hover { border-color: var(--primary-light); color: var(--primary); }
.calc-tab.active {
    background: linear-gradient(135deg, var(--primary), #1d4ed8);
    border-color: transparent;
    color: #fff;
    box-shadow: 0 4px 14px rgba(37, 99, 235, 0.3);
}

/* 面板 */
.calc-panel { animation: fadeIn 0.3s ease; }
.calc-panel[hidden] { display: none; }
@keyframes fadeIn { from { opacity: 0; transform: translateY(8px); } to { opacity: 1; transform: none; } }

/* 子 Tab（模块内切换，如 平面螺旋/磁芯、谐振模式/单独电感/电容、各拓扑） */
.calc-subtabs {
    display: flex;
    flex-wrap: wrap;
    gap: 0.4rem;
    background: rgba(241, 245, 249, 0.7);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 0.4rem;
    margin-bottom: 1.25rem;
}
.calc-subtab {
    flex: 1;
    min-width: 110px;
    padding: 0.6rem 0.8rem;
    border: none;
    background: transparent;
    color: var(--text-muted);
    font-size: 0.875rem;
    font-weight: 600;
    border-radius: 8px;
    cursor: pointer;
    transition: var(--transition);
    font-family: inherit;
}
.calc-subtab:hover { color: var(--primary); }
.calc-subtab.active { background: #fff; color: var(--primary); box-shadow: 0 1px 3px rgba(15, 23, 42, 0.12); }
.calc-subpanel[hidden] { display: none; }
.calc-subpanel { animation: fadeIn 0.25s ease; }

/* 计算卡片 */
.calc-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 1.75rem;
    box-shadow: var(--shadow-sm);
}
.calc-card-head {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1rem;
    flex-wrap: wrap;
    margin-bottom: 1.25rem;
}
.calc-card-head h3 { margin: 0; font-size: 1.2rem; letter-spacing: -0.01em; }
.calc-card-actions { display: flex; gap: 0.5rem; flex-wrap: wrap; }

.formula-toggle, .reset-btn, .copy-btn {
    padding: 0.45rem 0.9rem;
    border: 1px solid var(--border);
    background: #fff;
    color: var(--text-muted);
    font-size: 0.8rem;
    font-weight: 600;
    border-radius: 999px;
    cursor: pointer;
    transition: var(--transition);
    font-family: inherit;
}
.formula-toggle:hover, .reset-btn:hover, .copy-btn:hover { border-color: var(--primary-light); color: var(--primary); }
.formula-toggle[aria-expanded="true"] { background: var(--primary); border-color: var(--primary); color: #fff; }
.copy-btn.copied { background: #059669; border-color: #059669; color: #fff; }

/* 公式区 */
.formula-box {
    background: #f8fafc;
    border: 1px solid var(--border);
    border-left: 4px solid var(--primary);
    border-radius: 10px;
    padding: 1rem 1.25rem;
    margin-bottom: 1.5rem;
    font-size: 0.9rem;
    color: var(--text);
    line-height: 1.7;
}
.formula-box[hidden] { display: none; }
.formula-box p { margin: 0.35rem 0; }
.formula-box p strong { color: var(--primary); }
.formula-note { font-size: 0.8rem; color: var(--text-muted); font-style: italic; }

/* 表单网格 */
.form-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1rem 1.25rem;
    margin-bottom: 1.25rem;
}
.field { display: flex; flex-direction: column; }
.field-wide { grid-column: 1 / -1; }
.field label {
    font-size: 0.82rem;
    color: var(--text-muted);
    margin-bottom: 0.4rem;
    font-weight: 500;
}
.input-wrap { display: flex; gap: 0.5rem; align-items: stretch; }
.input-wrap input {
    flex: 1;
    min-width: 0;
    width: 100%;
    padding: 0.6rem 0.8rem;
    border: 1px solid var(--border);
    border-radius: 10px;
    font-size: 0.95rem;
    background: #fff;
    outline: none;
    transition: border-color 0.2s, box-shadow 0.2s;
    font-family: inherit;
}
.input-wrap input:focus, .input-wrap select:focus {
    border-color: var(--primary-light);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.12);
}
.input-wrap input:disabled { background: #f1f5f9; color: var(--text-muted); }
.input-wrap select {
    padding: 0.6rem 0.5rem;
    border: 1px solid var(--border);
    border-radius: 10px;
    font-size: 0.85rem;
    background: #f8fafc;
    cursor: pointer;
    min-width: 58px;
    font-family: inherit;
    color: var(--text);
}

.radio-group, .checkbox-group, .switch-group { display: flex; gap: 1.25rem; flex-wrap: wrap; padding: 0.4rem 0; }
.radio-group label, .checkbox-group label, .switch-group label {
    display: flex; align-items: center; gap: 0.4rem; cursor: pointer;
    font-size: 0.9rem; font-weight: 500; color: var(--text); margin: 0;
}

/* ===== 页面标题（无 hero，直接进工具） ===== */
.tool-head {
    padding: 1.75rem 0 1.5rem;
    margin-bottom: 1.5rem;
    border-bottom: 1px solid var(--border);
}
.tool-eyebrow {
    margin: 0 0 0.5rem;
    font-size: 0.78rem;
    font-weight: 700;
    letter-spacing: 0.12em;
    text-transform: uppercase;
    color: var(--primary);
}
.tool-head h1 {
    margin: 0;
    font-size: clamp(1.75rem, 3.4vw, 2.4rem);
    font-weight: 700;
    letter-spacing: -0.02em;
    line-height: 1.2;
}
.tool-lead {
    margin: 0.75rem 0 0;
    max-width: 78ch;
    color: var(--text-muted);
    font-size: 1rem;
    line-height: 1.75;
}
@media (max-width: 600px) {
    .tool-head { padding: 1.25rem 0 1.1rem; margin-bottom: 1.1rem; }
    .tool-lead { font-size: 0.94rem; }
}

/* 开关/复选（如“拆分 Lm/Ce/Cp”） */
.split-row { display: flex; align-items: center; gap: 0.6rem; flex-wrap: wrap; }
.split-check { display: inline-flex; align-items: center; gap: 0.4rem; font-size: 0.85rem; color: var(--text-muted); cursor: pointer; }

/* 顶部统一勾选条 */
.split-bar {
    display: flex;
    align-items: center;
    gap: 0.4rem 1.4rem;
    flex-wrap: wrap;
    padding: 0.65rem 0.9rem;
    margin-bottom: 1.1rem;
    background: #f8fafc;
    border: 1px dashed var(--border);
    border-radius: 10px;
}
.split-bar-title {
    font-size: 0.78rem;
    font-weight: 600;
    color: var(--text-muted);
    letter-spacing: 0.04em;
    padding-right: 0.6rem;
    border-right: 1px solid var(--border);
}
.split-bar .split-check { font-size: 0.86rem; }
.split-bar .split-check input { accent-color: var(--primary); cursor: pointer; }
:root.dark .split-bar { background: #0f172a; }
.field.hidden-field { display: none; }
.field.hidden-field.reveal { display: flex; }

/* 计算按钮 */
.calc-btn {
    width: 100%;
    padding: 0.85rem;
    background: linear-gradient(135deg, var(--primary), #1d4ed8);
    color: #fff;
    border: none;
    border-radius: 12px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    font-family: inherit;
    margin-bottom: 1.25rem;
}
.calc-btn:hover { transform: translateY(-2px); box-shadow: 0 8px 24px rgba(37, 99, 235, 0.35); }

/* 结果区 */
.result-box {
    background: #f0f9ff;
    border: 1px solid #bae6fd;
    border-radius: 12px;
    padding: 1.1rem 1.25rem;
}
.result-box h4 {
    color: #0369a1;
    font-size: 0.95rem;
    margin: 0.4rem 0 0.6rem;
    padding-bottom: 0.4rem;
    border-bottom: 1px dashed #7dd3fc;
}
.result-box h4:first-child { margin-top: 0; }
.result-item {
    display: flex;
    justify-content: space-between;
    align-items: baseline;
    gap: 1rem;
    padding: 0.4rem 0;
    font-size: 0.92rem;
    border-bottom: 1px solid rgba(125, 211, 252, 0.25);
}
.result-item:last-child { border-bottom: none; }
.result-item .rl { color: var(--text-muted); }
.result-item .rv { color: #0c4a6e; font-weight: 600; font-family: Consolas, "SFMono-Regular", monospace; text-align: right; }
.rv.good { color: #059669; }
.rv.warn { color: #dc2626; }

.design-note {
    margin-top: 2rem;
    font-size: 0.82rem;
    color: var(--text-muted);
    line-height: 1.7;
    background: rgba(241, 245, 249, 0.6);
    border-radius: 10px;
    padding: 0.9rem 1.1rem;
}

/* ===== 几何图 / 电路图布局 ===== */
.calc-layout {
    display: grid;
    grid-template-columns: 300px 1fr;
    gap: 1.5rem;
    align-items: start;
    margin-bottom: 1.25rem;
}
.calc-diagram {
    background: #f8fafc;
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 1rem;
    color: var(--text);
    display: flex;
    align-items: center;
    justify-content: center;
    position: sticky;
    top: 1rem;
}
.calc-diagram svg { width: 100%; height: auto; display: block; }
.calc-diagram .sch-stroke { stroke: var(--text); }
.calc-diagram .sch-accent { stroke: var(--primary); }
.calc-diagram .sch-fill { fill: var(--text); }
.calc-diagram .sch-muted { stroke: var(--text-muted); }
.calc-diagram text { fill: var(--text); font-family: inherit; font-size: 12px; }
.calc-diagram .sch-dim { stroke: #94a3b8; }
.calc-diagram .sch-dimtxt { fill: #64748b; font-style: italic; }

@media (max-width: 900px) {
    .form-grid { grid-template-columns: repeat(2, 1fr); }
    .calc-layout { grid-template-columns: 1fr; }
    .calc-diagram { position: static; }
}
@media (max-width: 600px) {
    .calc-card { padding: 1.25rem; }
    .form-grid { grid-template-columns: 1fr; }
    .calc-card-head { align-items: flex-start; }
    .calc-tabs { flex-wrap: nowrap; overflow-x: auto; padding-bottom: 0.25rem; }
    .calc-tab { flex: 0 0 auto; white-space: nowrap; }
}

/* 深色主题适配 */
:root.dark .calc-diagram { background: #0f172a; }
:root.dark .formula-box { background: #0f172a; }
:root.dark .result-box { background: #0b2942; border-color: #0c4a6e; }
:root.dark .result-box h4 { color: #7dd3fc; border-bottom-color: #155e75; }
:root.dark .result-item { border-bottom-color: rgba(45, 212, 191, 0.18); }
:root.dark .result-item .rv { color: #a5f3fc; }