/* =========================================================
   Scientific Notation Practice
   File:
   /interactive-learning-tools/scientific-notation/
   scientific-notation.css
   ========================================================= */

.scientific-notation-page {
    --sn-ink: #101827;
    --sn-text: #1f2937;
    --sn-muted: #5b6678;
    --sn-border: #dce3eb;
    --sn-soft: #f7f9fc;
    --sn-teal: #0f766e;
    --sn-teal-dark: #0b5f59;
    --sn-teal-light: #f0fdfa;
    --sn-teal-border: #99d5cf;
    background: #ffffff;
    color: var(--sn-text);
    font-family: "Inter", sans-serif;
}

.scientific-notation-page *,
.scientific-notation-page *::before,
.scientific-notation-page *::after {
    box-sizing: border-box;
}

.scientific-notation-page [hidden] {
    display: none !important;
}


/* =========================================================
   Shared Section Styles
   ========================================================= */

.scientific-notation-overview,
.scientific-notation-practice-section,
.scientific-notation-reminders,
.scientific-notation-final-cta {
    padding: 5rem 0;
}

.scientific-notation-overview,
.scientific-notation-reminders {
    background: var(--sn-soft);
}

.scientific-notation-practice-section,
.scientific-notation-final-cta {
    background: #ffffff;
}

.scientific-notation-section-heading {
    max-width: 790px;
    margin: 0 auto 2.5rem;
    text-align: center;
}

.scientific-notation-section-heading h2 {
    margin-bottom: 1rem;
    color: var(--sn-ink);
    font-size: clamp(1.75rem, 3vw, 2.4rem);
    font-weight: 800;
}

.scientific-notation-section-heading > p:last-child {
    margin-bottom: 0;
    color: var(--sn-muted);
    font-size: 1.05rem;
    line-height: 1.75;
}

.scientific-notation-eyebrow,
.scientific-notation-card-label {
    margin-bottom: 0.65rem;
    color: var(--sn-teal);
    font-size: 0.78rem;
    font-weight: 800;
    letter-spacing: 0.12em;
    text-transform: uppercase;
}


/* =========================================================
   Buttons and Focus
   ========================================================= */

.scientific-notation-page .btn-teal {
    border-color: var(--sn-teal);
    background: var(--sn-teal);
    color: #ffffff;
}

.scientific-notation-page .btn-teal:hover,
.scientific-notation-page .btn-teal:focus {
    border-color: var(--sn-teal-dark);
    background: var(--sn-teal-dark);
    color: #ffffff;
}

.scientific-notation-page .btn-outline-teal {
    border-color: var(--sn-teal);
    background: transparent;
    color: var(--sn-teal);
}

.scientific-notation-page .btn-outline-teal:hover,
.scientific-notation-page .btn-outline-teal:focus {
    border-color: var(--sn-teal);
    background: var(--sn-teal);
    color: #ffffff;
}

.scientific-notation-page button:disabled,
.scientific-notation-page input:disabled,
.scientific-notation-page select:disabled {
    cursor: not-allowed;
    opacity: 0.66;
}

.scientific-notation-page button:focus-visible,
.scientific-notation-page select:focus-visible,
.scientific-notation-page input:focus-visible {
    outline: 3px solid rgba(20, 184, 166, 0.28);
    outline-offset: 2px;
}


/* =========================================================
   Overview Cards
   ========================================================= */

.scientific-notation-overview-grid {
    display: grid;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 1rem;
}

.scientific-notation-overview-card {
    min-height: 100%;
    border: 1px solid var(--sn-border);
    border-radius: 1rem;
    background: #ffffff;
    padding: 1.5rem;
    box-shadow: 0 12px 30px rgba(16, 24, 39, 0.05);
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.scientific-notation-overview-card:hover {
    transform: translateY(-3px);
    box-shadow: 0 16px 34px rgba(16, 24, 39, 0.08);
}

.scientific-notation-overview-card h3 {
    margin-bottom: 0.75rem;
    color: var(--sn-ink);
    font-size: 1.1rem;
    font-weight: 800;
}

.scientific-notation-overview-card p {
    margin-bottom: 0;
    color: var(--sn-muted);
    line-height: 1.65;
}

.scientific-notation-step-number {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 2.65rem;
    height: 2.65rem;
    margin-bottom: 1rem;
    border-radius: 50%;
    background: var(--sn-teal);
    color: #ffffff;
    font-weight: 800;
}


/* =========================================================
   Main Tool Shell and Header
   ========================================================= */

.scientific-notation-tool {
    max-width: 1100px;
    margin: 0 auto;
    overflow: hidden;
    border: 1px solid var(--sn-border);
    border-radius: 1.25rem;
    background: #ffffff;
    box-shadow: 0 22px 55px rgba(16, 24, 39, 0.1);
}

.scientific-notation-tool-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 2rem;
    border-bottom: 1px solid #273449;
    background: var(--sn-ink);
    color: #ffffff;
    padding: 1.75rem 2rem;
}

.scientific-notation-tool-header h2 {
    margin-bottom: 0;
    color: #ffffff;
    font-size: clamp(1.45rem, 3vw, 2rem);
    font-weight: 800;
}

.scientific-notation-tool-header
.scientific-notation-eyebrow {
    color: #5eead4;
}

.scientific-notation-scoreboard {
    display: grid;
    grid-template-columns: repeat(3, minmax(80px, 1fr));
    gap: 0.75rem;
}

.scientific-notation-score-item {
    min-width: 90px;
    border: 1px solid rgba(255, 255, 255, 0.16);
    border-radius: 0.8rem;
    background: rgba(255, 255, 255, 0.08);
    padding: 0.75rem 0.9rem;
    text-align: center;
}

.scientific-notation-score-label {
    display: block;
    margin-bottom: 0.2rem;
    color: rgba(255, 255, 255, 0.72);
    font-size: 0.75rem;
    font-weight: 700;
    letter-spacing: 0.04em;
    text-transform: uppercase;
}

.scientific-notation-score-item strong {
    color: #ffffff;
    font-size: 1.4rem;
    font-weight: 800;
}


/* =========================================================
   Settings
   ========================================================= */

.scientific-notation-settings {
    display: grid;
    grid-template-columns: minmax(0, 1fr) minmax(0, 1.35fr) auto;
    gap: 1rem;
    align-items: end;
    border-bottom: 1px solid var(--sn-border);
    background: var(--sn-soft);
    padding: 1.5rem 2rem;
}

.scientific-notation-setting-group label {
    display: block;
    margin-bottom: 0.45rem;
    color: #273449;
    font-size: 0.9rem;
    font-weight: 700;
}

.scientific-notation-setting-group .form-select {
    min-height: 3rem;
    border-color: #cfd8e3;
    border-radius: 0.75rem;
    background-color: #ffffff;
}

.scientific-notation-setting-group .form-select:focus {
    border-color: var(--sn-teal);
    box-shadow: 0 0 0 0.2rem rgba(15, 118, 110, 0.14);
}

.scientific-notation-setting-actions {
    display: flex;
    gap: 0.65rem;
}

.scientific-notation-setting-actions .btn {
    min-height: 3rem;
    white-space: nowrap;
}


/* =========================================================
   Problem Display
   ========================================================= */

.scientific-notation-problem-panel {
	scroll-margin-top: 7rem;
    border-bottom: 1px solid var(--sn-border);
    background: #ffffff;
    padding: 2.25rem 2rem 2rem;
    text-align: center;
}

.scientific-notation-problem-header {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.75rem;
    margin-bottom: 0.75rem;
}

.scientific-notation-problem-label {
    margin-bottom: 0;
    color: var(--sn-teal);
    font-size: 0.8rem;
    font-weight: 800;
    letter-spacing: 0.09em;
    text-transform: uppercase;
}

.scientific-notation-difficulty-badge {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    border-radius: 999px;
    background: #e2e8f0;
    color: #475569;
    padding: 0.32rem 0.7rem;
    font-size: 0.72rem;
    font-weight: 800;
    letter-spacing: 0.04em;
    text-transform: uppercase;
}

.scientific-notation-difficulty-badge.easy {
    background: #dcfce7;
    color: #166534;
}

.scientific-notation-difficulty-badge.medium {
    background: #dbeafe;
    color: #1e40af;
}

.scientific-notation-difficulty-badge.hard {
    background: #fef3c7;
    color: #92400e;
}

.scientific-notation-problem-instruction {
    max-width: 760px;
    margin: 0 auto 1.3rem;
    color: #64748b;
    line-height: 1.65;
}

.scientific-notation-problem-expression {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-width: 10rem;
    min-height: 6.25rem;
    margin-bottom: 1rem;
    border: 1px solid var(--sn-teal-border);
    border-radius: 1rem;
    background: var(--sn-teal-light);
    color: var(--sn-teal);
    padding: 1rem 2rem;
    font-size: clamp(2.5rem, 8vw, 4rem);
    font-weight: 800;
    line-height: 1;
}

.scientific-notation-problem-expression sup {
    position: relative;
    top: -0.48em;
    display: inline-block;
    margin-left: 0.04em;
    font-size: 0.48em;
    line-height: 1;
}

.scientific-notation-final-answer sup,
.scientific-notation-example sup,
.scientific-notation-mini-example sup,
.scientific-notation-work-summary sup {
    position: relative;
    top: -0.32em;
    font-size: 0.62em;
    line-height: 0;
}

.scientific-notation-problem-relationship {
    max-width: 700px;
    margin: 0 auto 1.75rem;
    color: #356b67;
    font-size: 0.96rem;
    font-weight: 600;
    line-height: 1.65;
}


/* =========================================================
   Progress Rail
   ========================================================= */

.scientific-notation-progress {
    display: grid;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    max-width: 760px;
    margin: 0 auto;
    padding: 0;
    list-style: none;
}

.scientific-notation-progress li {
    position: relative;
    display: grid;
    gap: 0.5rem;
    justify-items: center;
    color: #8290a3;
    font-size: 0.78rem;
    font-weight: 800;
    letter-spacing: 0.04em;
    text-transform: uppercase;
}

.scientific-notation-progress li::before {
    content: "";
    position: absolute;
    z-index: 0;
    top: 1rem;
    right: 50%;
    width: 100%;
    height: 2px;
    background: #dce3eb;
}

.scientific-notation-progress li:first-child::before {
    display: none;
}

.scientific-notation-progress li span {
    position: relative;
    z-index: 1;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 2rem;
    height: 2rem;
    border: 2px solid #cbd5e1;
    border-radius: 50%;
    background: #ffffff;
    color: #64748b;
}

.scientific-notation-progress li.is-current {
    color: var(--sn-teal);
}

.scientific-notation-progress li.is-current span {
    border-color: var(--sn-teal);
    background: var(--sn-teal);
    color: #ffffff;
    box-shadow: 0 0 0 5px rgba(15, 118, 110, 0.12);
}

.scientific-notation-progress li.is-complete,
.scientific-notation-progress li.completed {
    color: #166534;
}

.scientific-notation-progress li.is-complete::before,
.scientific-notation-progress li.completed::before {
    background: #86cda9;
}

.scientific-notation-progress li.is-complete span,
.scientific-notation-progress li.completed span {
    border-color: #15803d;
    background: #15803d;
    color: #ffffff;
}


/* =========================================================
   Guided Workspace and Step Cards
   ========================================================= */

.scientific-notation-workspace {
    display: grid;
    gap: 1.25rem;
    background: var(--sn-soft);
    padding: 2rem;
}

.scientific-notation-step-card {
    border: 1px solid var(--sn-border);
    border-radius: 1rem;
    background: #ffffff;
    padding: 1.5rem;
    box-shadow: 0 8px 20px rgba(16, 24, 39, 0.035);
    transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

.scientific-notation-step-card[aria-disabled="true"] {
    background: #f8fafc;
    color: #6b7280;
}

.scientific-notation-step-card.is-active {
    border-color: var(--sn-teal-border);
    box-shadow: 0 0 0 3px rgba(15, 118, 110, 0.08);
}

.scientific-notation-step-card.is-complete,
.scientific-notation-step-card.completed {
    border-color: #86cda9;
}

.scientific-notation-step-heading {
    display: grid;
    grid-template-columns: auto 1fr auto;
    gap: 1rem;
    align-items: center;
    margin-bottom: 1rem;
}

.scientific-notation-step-heading h3 {
    margin-bottom: 0;
    color: var(--sn-ink);
    font-size: clamp(1.2rem, 2.6vw, 1.55rem);
    font-weight: 800;
}

.scientific-notation-step-card[aria-disabled="true"]
.scientific-notation-step-heading h3 {
    color: #64748b;
}

.scientific-notation-card-label {
    margin-bottom: 0.2rem;
}

.scientific-notation-work-step-number {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 2.7rem;
    height: 2.7rem;
    border-radius: 0.8rem;
    background: #e6fffb;
    color: var(--sn-teal);
    font-size: 1.05rem;
    font-weight: 800;
}

.scientific-notation-step-card.is-active
.scientific-notation-work-step-number {
    background: var(--sn-teal);
    color: #ffffff;
}

.scientific-notation-step-card.is-complete
.scientific-notation-work-step-number,
.scientific-notation-step-card.completed
.scientific-notation-work-step-number {
    background: #15803d;
    color: #ffffff;
}

.scientific-notation-step-status {
    border-radius: 999px;
    background: #e2e8f0;
    color: #64748b;
    padding: 0.35rem 0.7rem;
    font-size: 0.7rem;
    font-weight: 800;
    letter-spacing: 0.04em;
    text-transform: uppercase;
    white-space: nowrap;
}

.scientific-notation-step-card.is-active
.scientific-notation-step-status {
    background: #ccfbf1;
    color: var(--sn-teal);
}

.scientific-notation-step-card.is-complete
.scientific-notation-step-status,
.scientific-notation-step-card.completed
.scientific-notation-step-status {
    background: #dcfce7;
    color: #166534;
}

.scientific-notation-step-card > p,
.scientific-notation-step-card > div > p {
    color: var(--sn-muted);
    line-height: 1.65;
}

.scientific-notation-step-problem-panel {
    display: block;
    visibility: visible;
    opacity: 1;
    margin: 0 0 1.25rem;
    border: 1px solid var(--sn-border);
    border-radius: 1rem;
    background: #ffffff;
    color: var(--sn-ink);
}

.scientific-notation-step-card[aria-disabled="true"]
.scientific-notation-step-problem-panel {
    display: block;
    visibility: visible;
    opacity: 1;
}

.scientific-notation-step-problem-panel
.scientific-notation-problem-relationship {
    margin-bottom: 0;
}


/* =========================================================
   Inputs, Factors, and Choices
   ========================================================= */

.scientific-notation-input-row {
    display: grid;
    grid-template-columns: repeat(2, minmax(120px, 220px));
    gap: 1rem;
    margin: 1.25rem 0;
}

.scientific-notation-input-row.one-column {
    grid-template-columns: minmax(140px, 260px);
}

.scientific-notation-scientific-answer-row {
    display: flex;
    flex-wrap: wrap;
    align-items: end;
    gap: 0.85rem;
    margin: 1.25rem 0;
}

.scientific-notation-scientific-answer-row
.scientific-notation-input-group {
    width: min(100%, 220px);
}

.scientific-notation-scientific-answer-row
.scientific-notation-exponent-input {
    width: 120px;
}

.scientific-notation-times-ten {
    align-self: center;
    margin-top: 1.4rem;
    color: var(--sn-teal);
    font-size: 1.45rem;
    font-weight: 800;
    white-space: nowrap;
}

.scientific-notation-standard-input {
    width: min(100%, 360px);
}

.scientific-notation-input-group {
    display: grid;
    gap: 0.45rem;
}

.scientific-notation-input-group label,
.scientific-notation-answer-row > label {
    margin-bottom: 0;
    color: #273449;
    font-size: 0.9rem;
    font-weight: 800;
}

.scientific-notation-input-group .form-control,
.scientific-notation-answer-control .form-control,
.scientific-notation-factor-row input {
    min-height: 3.15rem;
    border: 2px solid #cfd8e3;
    border-radius: 0.75rem;
    background: #ffffff;
    color: var(--sn-ink);
    font-size: 1.12rem;
    font-weight: 800;
    text-align: center;
}

.scientific-notation-input-group .form-control:focus,
.scientific-notation-answer-control .form-control:focus,
.scientific-notation-factor-row input:focus {
    border-color: var(--sn-teal);
    box-shadow: 0 0 0 0.2rem rgba(15, 118, 110, 0.14);
}

.scientific-notation-input-group .form-control.correct,
.scientific-notation-answer-control .form-control.correct,
.scientific-notation-factor-row input.correct,
.scientific-notation-page .input-correct {
    border-color: #15803d;
    background: #f0fdf4;
}

.scientific-notation-input-group .form-control.incorrect,
.scientific-notation-answer-control .form-control.incorrect,
.scientific-notation-factor-row input.incorrect,
.scientific-notation-page .input-incorrect {
    border-color: #dc2626;
    background: #fef2f2;
}

.scientific-notation-factor-row {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 0.55rem;
    margin: 1.25rem 0;
}

.scientific-notation-factor-row:empty {
    display: none;
}

.scientific-notation-factor-row input {
    width: 4.75rem;
    padding-right: 0.45rem;
    padding-left: 0.45rem;
}

.scientific-notation-factor-row span,
.scientific-notation-factor-row .factor-operator {
    color: var(--sn-teal);
    font-size: 1.35rem;
    font-weight: 800;
}

.scientific-notation-choice-grid {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 0.85rem;
    margin: 1.25rem 0;
}

.scientific-notation-choice-grid button,
.scientific-notation-choice-grid .choice-button {
    width: 100%;
    min-height: 4rem;
    border: 2px solid var(--sn-border);
    border-radius: 0.9rem;
    background: #ffffff;
    color: #273449;
    padding: 0.9rem 1rem;
    font-size: 1rem;
    font-weight: 700;
    line-height: 1.45;
    text-align: center;
    cursor: pointer;
    transition: border-color 0.2s ease, background 0.2s ease,
        transform 0.2s ease;
}

.scientific-notation-choice-grid button:hover,
.scientific-notation-choice-grid button:focus-visible,
.scientific-notation-choice-grid .choice-button:hover,
.scientific-notation-choice-grid .choice-button:focus-visible {
    transform: translateY(-2px);
    border-color: #5eead4;
    background: var(--sn-teal-light);
}

.scientific-notation-choice-grid button.selected,
.scientific-notation-choice-grid button[aria-pressed="true"],
.scientific-notation-choice-grid .choice-button.selected {
    border-color: var(--sn-teal);
    background: #ccfbf1;
    color: var(--sn-teal-dark);
}

.scientific-notation-choice-grid button.correct,
.scientific-notation-choice-grid .choice-button.correct {
    border-color: #15803d;
    background: #dcfce7;
    color: #166534;
}

.scientific-notation-choice-grid button.incorrect,
.scientific-notation-choice-grid .choice-button.incorrect {
    border-color: #dc2626;
    background: #fef2f2;
    color: #991b1b;
}

.scientific-notation-step-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 0.75rem;
    margin-top: 1.25rem;
}


/* =========================================================
   Evaluation and Work Summaries
   ========================================================= */

.scientific-notation-calculation-trail {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 0.55rem;
    margin: 1.25rem 0;
    border: 1px solid var(--sn-teal-border);
    border-radius: 0.9rem;
    background: var(--sn-teal-light);
    color: #355d59;
    padding: 1rem 1.15rem;
    font-size: 1.05rem;
    font-weight: 700;
    line-height: 1.6;
}

.scientific-notation-calculation-trail > span,
.scientific-notation-calculation-trail .calculation-step {
    display: inline-flex;
    align-items: center;
    border-radius: 0.55rem;
    background: #ffffff;
    color: var(--sn-teal-dark);
    padding: 0.45rem 0.7rem;
}

.scientific-notation-answer-row {
    display: grid;
    gap: 0.5rem;
    max-width: 430px;
    margin: 1.25rem 0;
}

.scientific-notation-answer-control {
    display: grid;
    grid-template-columns: auto minmax(110px, 190px);
    gap: 0.75rem;
    align-items: center;
}

.scientific-notation-answer-control > span {
    color: var(--sn-teal);
    font-size: 1.35rem;
    font-weight: 800;
    white-space: nowrap;
}

.scientific-notation-feedback {
    margin-top: 1rem;
    border: 1px solid #cbd5e1;
    border-radius: 0.85rem;
    background: #f8fafc;
    color: #334155;
    padding: 1rem 1.15rem;
    font-weight: 600;
    line-height: 1.6;
}

.scientific-notation-feedback.success,
.scientific-notation-feedback.correct {
    border-color: #86cda9;
    background: #f0fdf4;
    color: #166534;
}

.scientific-notation-feedback.error,
.scientific-notation-feedback.incorrect {
    border-color: #f0a7a7;
    background: #fef2f2;
    color: #991b1b;
}

.scientific-notation-feedback.info {
    border-color: #93c5fd;
    background: #eff6ff;
    color: #1e40af;
}

.scientific-notation-work-summary {
    margin-top: 1rem;
    border-left: 4px solid #15803d;
    border-radius: 0.75rem;
    background: #f0fdf4;
    color: #166534;
    padding: 1rem 1.15rem;
    font-weight: 700;
    line-height: 1.65;
    animation: scientific-notation-fade-in 0.24s ease;
}


/* =========================================================
   Hint and Completion
   ========================================================= */

.scientific-notation-hint-area {
    border: 1px dashed var(--sn-teal-border);
    border-radius: 0.9rem;
    background: #ffffff;
    padding: 1rem 1.15rem;
}

.scientific-notation-hint-button {
    border: 0;
    background: transparent;
    color: var(--sn-teal);
    padding: 0;
    font-weight: 800;
    text-decoration: underline;
    text-underline-offset: 0.2rem;
}

.scientific-notation-hint-button:hover,
.scientific-notation-hint-button:focus {
    color: var(--sn-teal-dark);
}

.scientific-notation-hint {
    margin-top: 0.85rem;
    border-left: 4px solid var(--sn-teal);
    border-radius: 0.75rem;
    background: var(--sn-teal-light);
    color: #355d59;
    padding: 1rem 1.15rem;
    line-height: 1.65;
    animation: scientific-notation-fade-in 0.24s ease;
}

.scientific-notation-hint p:last-child {
    margin-bottom: 0;
}

.scientific-notation-completion {
    border: 1px solid #86cda9;
    border-radius: 1rem;
    background: #f0fdf4;
    padding: 1.75rem;
    text-align: center;
    animation: scientific-notation-fade-in 0.24s ease;
}

.scientific-notation-completion-icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 3.5rem;
    height: 3.5rem;
    margin-bottom: 1rem;
    border-radius: 50%;
    background: #15803d;
    color: #ffffff;
    font-size: 1.65rem;
    font-weight: 800;
}

.scientific-notation-completion h3 {
    margin-bottom: 0.65rem;
    color: #14532d;
    font-size: 1.6rem;
    font-weight: 800;
}

.scientific-notation-completion > p {
    max-width: 760px;
    margin-right: auto;
    margin-left: auto;
    color: #3f624b;
    line-height: 1.65;
}

.scientific-notation-final-answer {
    max-width: 760px;
    margin: 1.25rem auto;
    border: 1px solid #bbf7d0;
    border-radius: 0.85rem;
    background: #ffffff;
    color: #14532d;
    padding: 1rem 1.25rem;
    font-size: clamp(1.15rem, 3vw, 1.45rem);
    font-weight: 800;
    line-height: 1.65;
}

.scientific-notation-completion-explanation {
    margin-bottom: 1.35rem !important;
}


/* =========================================================
   Scientific Notation Reference
   ========================================================= */

.scientific-notation-reference-card {
    border: 1px solid var(--sn-border);
    border-radius: 1rem;
    background: #ffffff;
    padding: 1.5rem;
    animation: scientific-notation-fade-in 0.24s ease;
}

.scientific-notation-card-heading {
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    gap: 2rem;
    margin-bottom: 1.25rem;
}

.scientific-notation-card-heading h3 {
    margin-bottom: 0;
    color: var(--sn-ink);
    font-size: 1.35rem;
    font-weight: 800;
}

.scientific-notation-reference-note {
    max-width: 440px;
    margin-bottom: 0;
    color: var(--sn-muted);
    font-size: 0.92rem;
    line-height: 1.6;
}

.scientific-notation-rule-grid {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 0.8rem;
}

.scientific-notation-rule-grid article {
    display: grid;
    gap: 0.35rem;
    border: 1px solid var(--sn-teal-border);
    border-radius: 0.8rem;
    background: var(--sn-teal-light);
    color: #355d59;
    padding: 1rem;
    line-height: 1.5;
}

.scientific-notation-rule-grid strong {
    color: var(--sn-teal-dark);
    font-size: 1rem;
}

.scientific-notation-mini-example {
    margin-top: 0.25rem;
    color: var(--sn-teal-dark);
    font-weight: 800;
}

.scientific-notation-square-grid {
    display: grid;
    grid-template-columns: repeat(5, minmax(0, 1fr));
    gap: 0.65rem;
}

.scientific-notation-square-grid span {
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 3.1rem;
    border: 1px solid var(--sn-teal-border);
    border-radius: 0.7rem;
    background: var(--sn-teal-light);
    color: var(--sn-teal-dark);
    padding: 0.65rem 0.4rem;
    font-weight: 800;
    text-align: center;
}


/* =========================================================
   Reminder Cards
   ========================================================= */

.scientific-notation-reminders-grid {
    display: grid;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 1rem;
}

.scientific-notation-reminder-card {
    display: flex;
    flex-direction: column;
    min-height: 100%;
    border: 1px solid var(--sn-border);
    border-radius: 1rem;
    background: #ffffff;
    padding: 1.5rem;
    box-shadow: 0 10px 24px rgba(16, 24, 39, 0.04);
}

.scientific-notation-reminder-card h3 {
    margin-bottom: 0.65rem;
    color: var(--sn-ink);
    font-size: 1.05rem;
    font-weight: 800;
}

.scientific-notation-reminder-card p {
    margin-bottom: 1rem;
    color: var(--sn-muted);
    line-height: 1.65;
}

.scientific-notation-example {
    margin-top: auto;
    border-radius: 0.75rem;
    background: #e6fffb;
    color: var(--sn-teal-dark);
    padding: 0.85rem 1rem;
    font-weight: 800;
    line-height: 1.55;
    text-align: center;
}


/* =========================================================
   Bottom CTA
   ========================================================= */

.scientific-notation-final-cta-card {
    border-radius: 1.25rem;
    background: var(--sn-ink);
    color: #ffffff;
    padding: 2.25rem;
    text-align: center;
}

.scientific-notation-final-cta-card
.scientific-notation-eyebrow {
    color: #5eead4;
}

.scientific-notation-final-cta-card h2 {
    margin-bottom: 0.8rem;
    color: #ffffff;
    font-size: clamp(1.65rem, 3vw, 2.2rem);
    font-weight: 800;
}

.scientific-notation-final-cta-card p {
    max-width: 740px;
    margin: 0 auto 1.4rem;
    color: rgba(255, 255, 255, 0.78);
    line-height: 1.7;
}


/* =========================================================
   Animation
   ========================================================= */

@keyframes scientific-notation-fade-in {
    from {
        transform: translateY(5px);
        opacity: 0;
    }

    to {
        transform: translateY(0);
        opacity: 1;
    }
}

@media (prefers-reduced-motion: reduce) {
    .scientific-notation-overview-card,
    .scientific-notation-step-card,
    .scientific-notation-choice-grid button,
    .scientific-notation-work-summary,
    .scientific-notation-hint,
    .scientific-notation-completion,
    .scientific-notation-reference-card {
        animation: none;
        transition: none;
    }

    .scientific-notation-overview-card:hover,
    .scientific-notation-choice-grid button:hover {
        transform: none;
    }
}


/* =========================================================
   Responsive: Tablet
   ========================================================= */

@media (max-width: 992px) {
    .scientific-notation-overview-grid,
    .scientific-notation-reminders-grid {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }

    .scientific-notation-tool-header {
        align-items: flex-start;
        flex-direction: column;
    }

    .scientific-notation-scoreboard {
        width: 100%;
    }

    .scientific-notation-settings {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }

    .scientific-notation-setting-actions {
        grid-column: 1 / -1;
    }

    .scientific-notation-setting-actions .btn {
        flex: 1 1 180px;
    }

    .scientific-notation-square-grid {
        grid-template-columns: repeat(3, minmax(0, 1fr));
    }
}


/* =========================================================
   Responsive: Mobile
   ========================================================= */

@media (max-width: 768px) {
    .scientific-notation-overview,
    .scientific-notation-practice-section,
    .scientific-notation-reminders,
    .scientific-notation-final-cta {
        padding: 3.5rem 0;
    }

    .scientific-notation-tool-header,
    .scientific-notation-settings,
    .scientific-notation-problem-panel,
    .scientific-notation-workspace {
        padding-right: 1.25rem;
        padding-left: 1.25rem;
    }

    .scientific-notation-settings,
    .scientific-notation-choice-grid {
        grid-template-columns: 1fr;
    }

    .scientific-notation-setting-actions {
        grid-column: auto;
    }

    .scientific-notation-step-heading {
        grid-template-columns: auto 1fr;
    }

    .scientific-notation-step-status {
        grid-column: 2;
        justify-self: start;
    }

    .scientific-notation-card-heading {
        flex-direction: column;
        gap: 0.5rem;
    }

    .scientific-notation-reference-note {
        max-width: none;
    }

    .scientific-notation-rule-grid {
        grid-template-columns: 1fr;
    }
}


/* =========================================================
   Responsive: Small Mobile
   ========================================================= */

@media (max-width: 480px) {
    .scientific-notation-overview-grid,
    .scientific-notation-reminders-grid,
    .scientific-notation-square-grid,
    .scientific-notation-input-row {
        grid-template-columns: 1fr;
    }

    .scientific-notation-tool {
        border-radius: 1rem;
    }

    .scientific-notation-tool-header {
        padding: 1.35rem 1rem;
    }

    .scientific-notation-scoreboard {
        gap: 0.4rem;
    }

    .scientific-notation-score-item {
        min-width: 0;
        padding: 0.65rem 0.35rem;
    }

    .scientific-notation-score-label {
        font-size: 0.62rem;
    }

    .scientific-notation-score-item strong {
        font-size: 1.2rem;
    }

    .scientific-notation-settings,
    .scientific-notation-problem-panel,
    .scientific-notation-workspace {
        padding-right: 1rem;
        padding-left: 1rem;
    }

    .scientific-notation-problem-header {
        flex-direction: column;
    }

    .scientific-notation-problem-expression {
        min-width: 8.5rem;
        min-height: 5.25rem;
        padding: 0.85rem 1.35rem;
    }

    .scientific-notation-progress li {
        font-size: 0.62rem;
        letter-spacing: 0;
    }

    .scientific-notation-progress li span {
        width: 1.8rem;
        height: 1.8rem;
    }

    .scientific-notation-progress li::before {
        top: 0.9rem;
    }

    .scientific-notation-step-card,
    .scientific-notation-reference-card,
    .scientific-notation-completion {
        padding: 1.25rem 1rem;
    }

    .scientific-notation-step-heading {
        gap: 0.75rem;
    }

    .scientific-notation-work-step-number {
        width: 2.35rem;
        height: 2.35rem;
    }

    .scientific-notation-setting-actions,
    .scientific-notation-step-actions {
        flex-direction: column;
    }

    .scientific-notation-scientific-answer-row {
        align-items: stretch;
        flex-direction: column;
    }

    .scientific-notation-scientific-answer-row
    .scientific-notation-input-group,
    .scientific-notation-scientific-answer-row
    .scientific-notation-exponent-input {
        width: 100%;
    }

    .scientific-notation-times-ten {
        align-self: flex-start;
        margin-top: 0;
    }

    .scientific-notation-setting-actions .btn,
    .scientific-notation-step-actions .btn {
        width: 100%;
    }

    .scientific-notation-answer-control {
        grid-template-columns: 1fr;
    }

    .scientific-notation-answer-control > span {
        font-size: 1.2rem;
    }

    .scientific-notation-factor-row {
        gap: 0.4rem;
    }

    .scientific-notation-factor-row input {
        width: 4rem;
    }

    .scientific-notation-final-cta-card {
        padding: 1.75rem 1rem;
    }
}