/* Оболочка платформы. Оранжевым выделяется только интерактивное. */
* {
    box-sizing: border-box;
}

body {
    margin: 0;
    background: var(--iq-bg);
    color: var(--iq-text);
    font-family: var(--iq-font);
    line-height: 1.55;
}

.iq-container {
    width: 100%;
    max-width: 68rem;
    margin: 0 auto;
    padding: 0 1.5rem;
}

.iq-header {
    border-bottom: 1px solid var(--iq-border);
    background: var(--iq-surface-raised);
}

.iq-header__inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1rem;
    min-height: 4rem;
}

.iq-logo {
    font-size: 1.15rem;
    font-weight: 700;
    letter-spacing: -0.01em;
    color: var(--iq-text);
    text-decoration: none;
}

.iq-logo__accent {
    color: var(--iq-accent-600);
}

.iq-nav {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.iq-main {
    padding-top: 3rem;
    padding-bottom: 4rem;
    min-height: 60vh;
}

.iq-footer {
    border-top: 1px solid var(--iq-border);
    background: var(--iq-surface);
    padding: 1.5rem 0;
}

.iq-muted {
    color: var(--iq-text-muted);
    font-size: 0.9rem;
}

.iq-link {
    color: var(--iq-accent-700);
    text-decoration: none;
}

.iq-link:hover {
    text-decoration: underline;
}

.iq-button {
    display: inline-block;
    padding: 0.5rem 1rem;
    border: 1px solid transparent;
    border-radius: var(--iq-radius-small);
    background: var(--iq-accent-600);
    color: var(--iq-text-inverse);
    font-weight: 600;
    text-decoration: none;
}

.iq-button:hover {
    background: var(--iq-accent-700);
}

.iq-button:active {
    background: var(--iq-accent-active);
}

.iq-button--large {
    padding: 0.75rem 1.5rem;
    font-size: 1.05rem;
    margin-right: 1rem;
}

.iq-link:focus-visible,
.iq-button:focus-visible,
.iq-logo:focus-visible {
    outline: none;
    box-shadow: var(--iq-focus-ring);
    border-radius: var(--iq-radius-small);
}

.iq-hero {
    max-width: 40rem;
}

.iq-hero__title {
    margin: 0 0 0.75rem;
    font-size: 2.25rem;
    line-height: 1.2;
    letter-spacing: -0.02em;
}

.iq-hero__lead {
    margin: 0 0 2rem;
    font-size: 1.15rem;
    color: var(--iq-text-muted);
}

/* Контентные страницы */
.iq-page-title {
    margin: 0 0 1rem;
    font-size: 1.9rem;
    line-height: 1.25;
    letter-spacing: -0.02em;
}

.iq-lead {
    color: var(--iq-text-muted);
    margin: 0 0 1rem;
}

.iq-breadcrumbs {
    display: flex;
    gap: 0.5rem;
    margin-bottom: 1rem;
    font-size: 0.9rem;
}

.iq-badge {
    display: inline-block;
    padding: 0.15rem 0.6rem;
    border-radius: 999px;
    background: var(--iq-accent-100);
    color: var(--iq-accent-700);
    font-size: 0.85rem;
    font-weight: 600;
}

.iq-badge--quiet {
    background: var(--iq-surface);
    color: var(--iq-text-muted);
    font-weight: 500;
}

.iq-cards {
    display: grid;
    gap: 1rem;
    grid-template-columns: repeat(auto-fill, minmax(18rem, 1fr));
    list-style: none;
    margin: 1.5rem 0 0;
    padding: 0;
}

.iq-card {
    padding: 1.25rem;
    border: 1px solid var(--iq-border);
    border-radius: var(--iq-radius);
    background: var(--iq-surface-raised);
}

.iq-card__title {
    display: block;
    margin-bottom: 0.5rem;
    color: var(--iq-text);
    font-size: 1.1rem;
    font-weight: 600;
    text-decoration: none;
}

.iq-card__title:hover {
    color: var(--iq-accent-700);
}

.iq-card__text {
    margin: 0 0 0.75rem;
    color: var(--iq-text-muted);
}

.iq-card__meta {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    margin: 0;
    font-size: 0.9rem;
}

.iq-module {
    margin-top: 2rem;
    padding-top: 1.25rem;
    border-top: 1px solid var(--iq-border);
}

.iq-module__title {
    margin: 0 0 0.75rem;
    font-size: 1.25rem;
}

.iq-lessons {
    margin: 0;
    padding-left: 1.25rem;
    line-height: 2;
}

.iq-lesson-nav {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1rem;
    margin-top: 2.5rem;
    padding-top: 1.25rem;
    border-top: 1px solid var(--iq-border);
}

/* Теория урока */
.iq-prose {
    max-width: 44rem;
    font-size: 1.05rem;
}

.iq-prose h2 {
    margin-top: 2rem;
    font-size: 1.35rem;
}

.iq-prose h3 {
    margin-top: 1.5rem;
    font-size: 1.15rem;
}

.iq-prose code {
    padding: 0.1rem 0.35rem;
    border-radius: var(--iq-radius-small);
    background: var(--iq-surface);
    font-family: var(--iq-font-mono);
    font-size: 0.95em;
}

.iq-prose pre {
    padding: 1rem;
    border-radius: var(--iq-radius);
    background: var(--iq-surface);
    overflow-x: auto;
}

.iq-prose table {
    border-collapse: collapse;
    width: 100%;
}

.iq-prose th,
.iq-prose td {
    padding: 0.5rem 0.75rem;
    border: 1px solid var(--iq-border);
    text-align: left;
}

/* Формы */
.iq-panel {
    margin: 2rem 0;
    padding: 1.5rem;
    border: 1px solid var(--iq-border);
    border-radius: var(--iq-radius);
    background: var(--iq-surface);
}

.iq-panel__title {
    margin: 0 0 1rem;
    font-size: 1.2rem;
}

.iq-form {
    display: grid;
    gap: 0.35rem;
    max-width: 40rem;
}

.iq-form--compact {
    margin-top: 1rem;
}

.iq-form__row {
    display: flex;
    gap: 1.5rem;
}

.iq-inline-form {
    margin: 1rem 0;
}

.iq-label {
    margin-top: 0.75rem;
    font-size: 0.9rem;
    font-weight: 600;
}

.iq-input,
.iq-select {
    padding: 0.5rem 0.65rem;
    border: 1px solid var(--iq-border);
    border-radius: var(--iq-radius-small);
    background: var(--iq-surface-raised);
    color: var(--iq-text);
    font: inherit;
    width: 100%;
}

.iq-input--narrow {
    width: 6rem;
}

.iq-input--code {
    font-family: var(--iq-font-mono);
    font-size: 0.95rem;
}

.iq-input:focus-visible,
.iq-select:focus-visible {
    outline: none;
    border-color: var(--iq-accent-600);
    box-shadow: var(--iq-focus-ring);
}

.iq-form .iq-button,
.iq-form .iq-button--secondary {
    justify-self: start;
    margin-top: 1rem;
    border: none;
    cursor: pointer;
    font: inherit;
    font-weight: 600;
}

.iq-button--secondary {
    display: inline-block;
    padding: 0.5rem 1rem;
    border: 1px solid var(--iq-border);
    border-radius: var(--iq-radius-small);
    background: var(--iq-surface-raised);
    color: var(--iq-text);
    cursor: pointer;
    font: inherit;
    font-weight: 600;
    text-decoration: none;
}

.iq-button--secondary:hover {
    background: var(--iq-accent-50);
}

.iq-filter {
    display: flex;
    align-items: flex-end;
    gap: 0.75rem;
    margin: 1.5rem 0;
}

.iq-filter__label {
    font-size: 0.9rem;
    font-weight: 600;
}

.iq-filter .iq-select {
    width: 8rem;
}

.iq-errors {
    color: var(--iq-error);
}

/* Тренажер */
.iq-trainer {
    max-width: 44rem;
}

.iq-progress {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-bottom: 2rem;
}

.iq-progress__track {
    flex: 1;
    height: 0.5rem;
    border-radius: 999px;
    background: var(--iq-accent-100);
    overflow: hidden;
}

.iq-progress__fill {
    height: 100%;
    background: var(--iq-accent-500);
    transition: width 0.2s ease;
}

.iq-progress__label {
    color: var(--iq-text-muted);
    font-size: 0.9rem;
    white-space: nowrap;
}

.iq-task__title {
    margin: 0 0 0.75rem;
    font-size: 1.5rem;
}

.iq-task__stem {
    margin: 0 0 1.5rem;
    font-size: 1.05rem;
}

.iq-part {
    margin-top: 2rem;
    padding-top: 1.5rem;
    border-top: 1px solid var(--iq-border);
}

.iq-part__prompt {
    margin: 0 0 1rem;
    font-size: 1.05rem;
    font-weight: 600;
}

.iq-part__mark {
    margin-right: 0.35rem;
    color: var(--iq-accent-700);
}

.iq-part__actions {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin: 1rem 0;
}

.iq-part__actions .iq-button {
    border: none;
    cursor: pointer;
    font: inherit;
    font-weight: 600;
}

.iq-answer {
    display: grid;
    gap: 0.35rem;
}

.iq-answer__hint {
    margin: 0;
    font-size: 0.85rem;
}

.iq-hints {
    margin: 1rem 0;
}

.iq-hints__list {
    margin: 0 0 0.75rem;
    padding: 0.75rem 1rem 0.75rem 2rem;
    border-radius: var(--iq-radius);
    background: var(--iq-warning-bg);
}

.iq-hints__item {
    margin: 0.25rem 0;
}

.iq-hints__button {
    border: 1px solid var(--iq-border);
    cursor: pointer;
}

.iq-verdict:empty {
    display: none;
}

.iq-verdict {
    margin-top: 1rem;
    padding: 0.75rem 1rem;
    border-radius: var(--iq-radius);
    border-left: 3px solid transparent;
}

.iq-verdict--correct {
    background: rgb(26 127 55 / 0.08);
    border-left-color: var(--iq-success);
    color: var(--iq-success);
}

.iq-verdict--incorrect {
    background: rgb(180 35 24 / 0.07);
    border-left-color: var(--iq-error);
    color: var(--iq-error);
}

.iq-verdict--self,
.iq-verdict--note {
    background: var(--iq-surface);
    border-left-color: var(--iq-accent-500);
    color: var(--iq-text);
}

.iq-verdict__text {
    margin: 0;
    font-weight: 600;
}

.iq-verdict__mark {
    margin-right: 0.5rem;
    font-weight: 700;
}

.iq-verdict__solution {
    margin-top: 0.75rem;
    padding-top: 0.75rem;
    border-top: 1px solid var(--iq-border);
    color: var(--iq-text);
    font-weight: 400;
}

.iq-verdict__title {
    margin: 0 0 0.35rem;
    font-size: 0.9rem;
    text-transform: uppercase;
    letter-spacing: 0.04em;
    color: var(--iq-text-muted);
}

.iq-task__reasoning {
    margin-top: 2rem;
}

.iq-trainer__done {
    padding: 2rem 0;
}

.iq-errors ul {
    margin: 0.5rem 0;
    padding-left: 1.25rem;
}

/* Редактор задачи: форма слева, взгляд ученика справа */
.iq-editor {
    display: grid;
    gap: 2rem;
    grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
    align-items: start;
}

@media (max-width: 60rem) {
    .iq-editor {
        grid-template-columns: minmax(0, 1fr);
    }
}

.iq-editor__part {
    margin-top: 1.5rem;
    padding: 1rem 1.25rem;
    border: 1px solid var(--iq-border);
    border-radius: var(--iq-radius);
    background: var(--iq-surface);
}

.iq-editor__part-title {
    margin: 0 0 0.75rem;
    font-size: 1rem;
}

.iq-editor__actions {
    display: flex;
    flex-wrap: wrap;
    gap: 0.75rem;
    margin-top: 1.5rem;
}

.iq-editor__preview {
    position: sticky;
    top: 1rem;
    padding: 1rem 1.25rem;
    border: 1px solid var(--iq-border);
    border-radius: var(--iq-radius);
    background: var(--iq-surface-raised);
}

.iq-editor__preview-title {
    margin: 0 0 1rem;
    font-size: 0.9rem;
    text-transform: uppercase;
    letter-spacing: 0.04em;
    color: var(--iq-text-muted);
}

.iq-warnings {
    padding: 0.75rem 1rem;
    border-radius: var(--iq-radius);
    background: var(--iq-warning-bg);
}

.iq-warnings__title {
    margin: 0 0 0.25rem;
    font-weight: 600;
}

.iq-notice {
    padding: 0.75rem 1rem;
    border-radius: var(--iq-radius);
    background: var(--iq-accent-50);
    color: var(--iq-accent-700);
}

.iq-fieldset {
    margin: 1rem 0;
    padding: 0.75rem 1rem;
    border: 1px solid var(--iq-border);
    border-radius: var(--iq-radius);
}

.iq-check {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    margin: 0.35rem 0;
}

.iq-link-button {
    padding: 0;
    border: 0;
    background: none;
    color: var(--iq-accent-600);
    font: inherit;
    text-decoration: underline;
    cursor: pointer;
}

.iq-button--quiet {
    background: var(--iq-surface);
    color: var(--iq-text);
    border: 1px solid var(--iq-border);
}

.iq-choice {
    list-style: none;
    margin: 0;
    padding: 0;
    display: grid;
    gap: 0.35rem;
}

.iq-choice__option {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

/* Обучение: зачисление, прогресс, уверенность по темам */
.iq-badge--done {
    background: var(--iq-accent-500);
    color: var(--iq-text-inverse);
}

.iq-enrollment {
    margin: 1.5rem 0;
    padding: 1rem 1.25rem;
    border: 1px solid var(--iq-border);
    border-radius: var(--iq-radius);
    background: var(--iq-surface);
}

.iq-enrollment__progress {
    margin: 0 0 0.5rem;
}

.iq-lesson-progress {
    margin: 2rem 0 1rem;
}

.iq-section {
    margin-top: 2.5rem;
}

.iq-section__title {
    margin: 0 0 0.75rem;
    font-size: 1.25rem;
}

.iq-progress-list,
.iq-mastery,
.iq-suggestions {
    list-style: none;
    margin: 0;
    padding: 0;
    display: grid;
    gap: 0.75rem;
}

.iq-progress-item,
.iq-mastery__item,
.iq-suggestions li {
    display: flex;
    flex-wrap: wrap;
    align-items: baseline;
    gap: 0.75rem;
    padding: 0.75rem 1rem;
    border: 1px solid var(--iq-border);
    border-radius: var(--iq-radius);
    background: var(--iq-surface-raised);
}

.iq-mastery__title {
    font-weight: 600;
    min-width: 12rem;
}

.iq-mastery__value {
    color: var(--iq-accent-700);
    font-weight: 600;
}