@charset "UTF-8";

html,
body {
    overflow-x: hidden;
}

.tool-hero {
    background: linear-gradient(135deg, #0f766e 0%, #0ea5e9 100%);
    color: #fff;
    padding: 2.8rem 0;
    text-align: center;
}

.tool-hero h1 {
    font-size: 2rem;
    margin-bottom: 0.45rem;
}

.tool-hero p {
    opacity: 0.95;
    margin: 0;
}

.hero-notes {
    margin-top: 1rem;
    display: flex;
    justify-content: center;
    gap: 0.5rem;
    flex-wrap: wrap;
}

.hero-notes span {
    background: rgba(255, 255, 255, 0.18);
    border: 1px solid rgba(255, 255, 255, 0.45);
    border-radius: 999px;
    padding: 0.2rem 0.65rem;
    font-size: 0.78rem;
    font-weight: 700;
}

.tool-area {
    padding: 2rem 0 2.5rem;
}

.tool-shell {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1rem;
}

.tool-col {
    background: #fff;
    border: 1px solid #dbe4f0;
    border-radius: 14px;
    padding: 1.2rem;
    box-shadow: 0 8px 26px rgba(15, 23, 42, 0.05);
}

.tool-col h2,
.visual-block h2,
.process-block h2 {
    margin: 0 0 0.9rem;
    font-size: 1.1rem;
    color: #0f172a;
}

.form-group {
    margin-bottom: 0.9rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.35rem;
    font-size: 0.84rem;
    color: #334155;
    font-weight: 600;
}

.form-group input {
    width: 100%;
    box-sizing: border-box;
    border: 1px solid #cbd5e1;
    border-radius: 8px;
    padding: 0.56rem 0.7rem;
    font-size: 0.95rem;
}

.form-group select {
    width: 100%;
    box-sizing: border-box;
    border: 1px solid #cbd5e1;
    border-radius: 8px;
    padding: 0.56rem 0.7rem;
    font-size: 0.95rem;
    background: #fff;
}

.equation-highlight {
    margin: 0.5rem 0 0.9rem;
    padding: 0.65rem 0.85rem;
    border: 1px solid #bfdbfe;
    border-radius: 10px;
    background: linear-gradient(180deg, #eff6ff 0%, #f8fafc 100%);
    color: #0f172a;
    font-size: 1.08rem;
    font-weight: 800;
    line-height: 1.45;
    word-break: break-word;
}

.equation-subtext {
    margin: -0.35rem 0 0.8rem;
    color: #475569;
    font-size: 0.88rem;
}

.slider-line {
    position: static;
    top: auto;
    right: auto;
    bottom: auto;
    left: auto;
    width: auto;
    background: transparent;
    box-shadow: none;
    z-index: auto;
    pointer-events: auto;
    display: grid;
    grid-template-columns: auto 1fr auto;
    gap: 0.55rem;
    align-items: center;
    margin-top: 0.4rem;
}

.slider-line label {
    font-size: 0.82rem;
    color: #334155;
    font-weight: 600;
}

.slider-line input[type="range"] {
    width: 100%;
}

.slider-line strong {
    color: #0f766e;
    min-width: 30px;
    text-align: right;
}

.result-grid {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 0.75rem;
}

.result-card {
    margin: 0;
    border: 1px solid #dbe4f0;
    border-radius: 12px;
    background: linear-gradient(180deg, #f8fafc, #f1f5f9);
    padding: 0.8rem;
}

.result-label {
    margin: 0 0 0.4rem;
    color: #475569;
    font-size: 0.75rem;
    font-weight: 700;
}

.result-value {
    margin: 0;
    color: #0f172a;
    font-size: 1rem;
    font-weight: 800;
    line-height: 1.35;
}

.calc-overview {
    margin: 0 0 0.9rem;
    display: grid;
    gap: 0.55rem;
}

.calc-overview-item {
    border: 1px solid #bfdbfe;
    border-radius: 10px;
    background: linear-gradient(180deg, #eff6ff 0%, #f8fafc 100%);
    padding: 0.58rem 0.72rem;
}

.calc-overview-item h3 {
    margin: 0 0 0.25rem;
    color: #0f172a;
    font-size: 0.88rem;
}

.calc-overview-item p {
    margin: 0;
    color: #475569;
    font-size: 0.82rem;
    line-height: 1.5;
}

.visual-block {
    margin-top: 1rem;
    background: #fff;
    border: 1px solid #dbe4f0;
    border-radius: 14px;
    padding: 1rem;
    box-shadow: 0 8px 26px rgba(15, 23, 42, 0.05);
    overflow: hidden;
}

#plotCanvas {
    width: 100%;
    height: auto;
    border: 1px solid #e2e8f0;
    border-radius: 10px;
    background: #ffffff;
}

.visual-block canvas {
    display: block;
    width: 100%;
    height: auto;
    max-width: 100%;
}

.process-block {
    margin-top: 1rem;
    background: #fff;
    border: 1px solid #dbe4f0;
    border-radius: 14px;
    padding: 1rem;
    box-shadow: 0 8px 26px rgba(15, 23, 42, 0.05);
}

.process-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 0.8rem;
    margin-bottom: 0.9rem;
}

.process-header h2 {
    margin: 0;
}

.process-toggle {
    border: 1px solid #bfdbfe;
    background: #eff6ff;
    color: #0f172a;
    border-radius: 999px;
    padding: 0.3rem 0.7rem;
    font-size: 0.8rem;
    font-weight: 700;
    cursor: pointer;
}

.process-block ol {
    margin: 0;
    padding-left: 1.25rem;
}

.process-block ul {
    margin: 0;
    padding-left: 1.25rem;
}

.process-block .plain-steps {
    list-style: none;
    padding-left: 0;
}

.process-block li {
    color: #334155;
    margin-bottom: 0.45rem;
    line-height: 1.55;
}

.process-groups {
    display: grid;
    gap: 0.7rem;
}

.process-group {
    border: 1px solid #dbe4f0;
    border-radius: 10px;
    padding: 0.75rem 0.85rem;
    background: #ffffff;
}

.process-group h3 {
    margin: 0 0 0.45rem;
    color: #0f172a;
    font-size: 0.95rem;
}

.process-group ul {
    margin: 0;
    padding-left: 1.15rem;
}

.process-group li {
    color: #334155;
    margin-bottom: 0.4rem;
    line-height: 1.55;
}

.process-empty {
    margin: 0;
    color: #64748b;
}

.use-cases-section,
.sample-problems-section {
    padding: 2.2rem 0;
}

.use-cases-section h2,
.sample-problems-section h2 {
    text-align: center;
    margin: 0 0 1.2rem;
    color: #0f172a;
    font-size: 1.45rem;
}

.use-cases-grid {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 0.9rem;
}

.use-case-card {
    background: #ffffff;
    border: 1px solid #dbe4f0;
    border-radius: 12px;
    padding: 1rem;
    box-shadow: 0 8px 20px rgba(15, 23, 42, 0.05);
}

.use-case-card h3 {
    margin: 0 0 0.4rem;
    font-size: 1rem;
    color: #0f172a;
}

.use-case-card p {
    margin: 0;
    color: #475569;
    line-height: 1.6;
    font-size: 0.93rem;
}

.problem-list {
    max-width: 900px;
    margin: 0 auto;
}

.problem-list details {
    background: #ffffff;
    border: 1px solid #dbe4f0;
    border-radius: 12px;
    padding: 0.85rem 1rem;
    margin-bottom: 0.7rem;
    box-shadow: 0 8px 20px rgba(15, 23, 42, 0.05);
}

.problem-list summary {
    cursor: pointer;
    font-weight: 700;
    color: #0f172a;
}

.problem-list p {
    margin: 0.6rem 0 0;
    color: #475569;
    line-height: 1.65;
    font-size: 0.93rem;
}

.formula-section {
    padding: 2.2rem 0;
}

.formula-section h2 {
    text-align: center;
    margin: 0 0 1.2rem;
    color: #0f172a;
    font-size: 1.45rem;
}

.formula-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 0.9rem;
}

.formula-card {
    background: #ffffff;
    border: 1px solid #dbe4f0;
    border-radius: 12px;
    padding: 1rem;
    box-shadow: 0 8px 20px rgba(15, 23, 42, 0.05);
}

.formula-name {
    margin: 0 0 0.35rem;
    font-size: 0.95rem;
    color: #334155;
    font-weight: 700;
}

.formula-exp {
    margin: 0;
    color: #0f172a;
    font-size: 1.05rem;
    font-weight: 800;
}

@media (max-width: 900px) {
    .tool-shell {
        grid-template-columns: 1fr;
    }

    .result-grid {
        grid-template-columns: 1fr;
    }

    .use-cases-grid {
        grid-template-columns: 1fr;
    }
}