:root {
    --bg: #f5f7fb;
    --surface: #ffffff;
    --surface-soft: #f8fafc;
    --text: #172033;
    --muted: #6b7280;
    --border: #e4e8f0;
    --accent: #315ca8;
    --accent-dark: #254a89;
    --accent-soft: #eaf0fb;
    --success: #247451;
    --success-soft: #eaf7f0;
    --danger: #a23939;
    --danger-soft: #fff0f0;
    --shadow: 0 8px 24px rgba(31, 42, 68, .06);
}

* {
    box-sizing: border-box;
}

html {
    color-scheme: light;
}

body {
    margin: 0;
    background: var(--bg);
    color: var(--text);
    font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
    font-size: 16px;
    line-height: 1.45;
}

button,
input,
select {
    font: inherit;
}

button,
a {
    -webkit-tap-highlight-color: transparent;
}

a {
    color: inherit;
}

code {
    background: #eef1f6;
    padding: 2px 5px;
    border-radius: 5px;
    font-size: .9em;
}

.app-shell {
    min-height: 100vh;
    display: grid;
    grid-template-columns: 245px minmax(0, 1fr);
}

.sidebar {
    position: sticky;
    top: 0;
    height: 100vh;
    background: var(--surface);
    border-right: 1px solid var(--border);
    padding: 20px 16px;
    display: flex;
    flex-direction: column;
    gap: 20px;
    z-index: 20;
}

.brand {
    display: flex;
    align-items: center;
    gap: 11px;
    text-decoration: none;
    padding: 4px 7px;
}

.brand-mark {
    width: 42px;
    height: 42px;
    display: grid;
    place-items: center;
    border-radius: 12px;
    background: var(--accent);
    color: #fff;
    flex: 0 0 auto;
}

.brand-mark svg {
    width: 24px;
    height: 24px;
}

.brand strong,
.login-brand strong {
    display: block;
    font-size: 16px;
}

.brand small,
.login-brand small {
    display: block;
    color: var(--muted);
    margin-top: 1px;
    font-size: 12px;
}

.nav {
    flex: 1;
    overflow-y: auto;
}

.nav-item {
    width: 100%;
    border: 0;
    background: transparent;
    color: #5f6879;
    padding: 10px 11px;
    border-radius: 10px;
    display: flex;
    align-items: center;
    gap: 10px;
    text-decoration: none;
    text-align: left;
    cursor: pointer;
    margin: 2px 0;
}

.nav-item:hover {
    background: var(--surface-soft);
    color: var(--text);
}

.nav-item.active {
    background: var(--accent-soft);
    color: var(--accent);
    font-weight: 600;
}

.nav-item.muted {
    opacity: .68;
}

.nav-section {
    color: #9aa1ad;
    font-size: 11px;
    font-weight: 700;
    letter-spacing: .08em;
    text-transform: uppercase;
    padding: 18px 11px 6px;
}

.sidebar-footer {
    border-top: 1px solid var(--border);
    padding-top: 15px;
}

.user-mini {
    display: flex;
    gap: 10px;
    align-items: center;
    margin-bottom: 10px;
}

.user-mini-text {
    min-width: 0;
}

.user-mini-text strong,
.user-mini-text small {
    display: block;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.user-mini-text strong {
    font-size: 13px;
}

.user-mini-text small {
    color: var(--muted);
    font-size: 12px;
}

.avatar {
    width: 38px;
    height: 38px;
    border-radius: 50%;
    display: inline-grid;
    place-items: center;
    background: var(--accent-soft);
    color: var(--accent);
    font-weight: 700;
    font-size: 13px;
    flex: 0 0 auto;
}

.avatar.small {
    width: 34px;
    height: 34px;
}

.logout-button {
    width: 100%;
    border: 1px solid var(--border);
    background: var(--surface);
    color: var(--muted);
    border-radius: 9px;
    padding: 8px 10px;
    cursor: pointer;
}

.logout-button:hover {
    color: var(--danger);
    border-color: #e7c6c6;
}

.main-wrap {
    min-width: 0;
}

.topbar {
    min-height: 80px;
    background: rgba(255, 255, 255, .92);
    border-bottom: 1px solid var(--border);
    display: flex;
    align-items: center;
    padding: 15px 28px;
    position: sticky;
    top: 0;
    z-index: 10;
}

.topbar > div:first-of-type {
    flex: 1;
}

.topbar small {
    color: var(--muted);
    font-size: 12px;
}

.topbar h1 {
    margin: 2px 0 0;
    font-size: 21px;
    line-height: 1.2;
}

.topbar-user {
    margin-left: auto;
}

.mobile-menu {
    display: none;
    border: 1px solid var(--border);
    border-radius: 9px;
    background: var(--surface);
    padding: 7px 10px;
    margin-right: 12px;
    cursor: pointer;
}

.content {
    padding: 26px 28px 42px;
    max-width: 1500px;
    margin: 0 auto;
}

.app-notice {
    background: var(--accent-soft);
    color: var(--accent-dark);
    border: 1px solid #d4e0f5;
    border-radius: 11px;
    padding: 11px 14px;
    margin-bottom: 18px;
}

.metric-grid {
    display: grid;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 15px;
    margin-bottom: 20px;
}

.metric-card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 14px;
    padding: 18px;
    display: flex;
    align-items: center;
    gap: 14px;
    box-shadow: var(--shadow);
}

.metric-icon {
    width: 42px;
    height: 42px;
    border-radius: 11px;
    display: grid;
    place-items: center;
    background: var(--accent-soft);
    color: var(--accent);
    font-size: 20px;
}

.metric-card span,
.metric-card small {
    display: block;
}

.metric-card span {
    color: var(--muted);
    font-size: 13px;
}

.metric-card strong {
    display: block;
    font-size: 27px;
    line-height: 1.15;
    margin: 2px 0;
}

.metric-card small {
    color: #9198a5;
    font-size: 11px;
}

.dashboard-grid {
    display: grid;
    grid-template-columns: minmax(0, 1.45fr) minmax(300px, .75fr);
    gap: 20px;
    margin-bottom: 20px;
}

.lower-grid {
    grid-template-columns: minmax(0, 1.15fr) minmax(320px, .85fr);
}

.panel {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 14px;
    padding: 20px;
    box-shadow: var(--shadow);
    min-width: 0;
}

.panel-header {
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    gap: 15px;
    margin-bottom: 20px;
}

.panel-header h2 {
    margin: 0;
    font-size: 16px;
}

.panel-header p {
    margin: 4px 0 0;
    color: var(--muted);
    font-size: 12px;
}

.ghost-button {
    border: 1px solid var(--border);
    background: var(--surface);
    color: var(--accent);
    border-radius: 9px;
    padding: 7px 10px;
    cursor: pointer;
    white-space: nowrap;
}

.progress-list {
    display: grid;
    gap: 20px;
}

.course-progress-top {
    display: flex;
    justify-content: space-between;
    gap: 14px;
    align-items: flex-start;
    margin-bottom: 8px;
}

.course-progress-top strong,
.course-progress-top small {
    display: block;
}

.course-progress-top strong {
    font-size: 14px;
}

.course-progress-top small {
    color: var(--muted);
    margin-top: 3px;
    font-size: 12px;
}

.course-progress-top > span {
    font-weight: 700;
    font-size: 13px;
}

.progress-track {
    height: 10px;
    border-radius: 999px;
    overflow: hidden;
    background: #edf1f7;
}

.progress-track span {
    display: block;
    height: 100%;
    background: var(--accent);
    border-radius: inherit;
}

.class-date {
    width: 72px;
    border-radius: 12px;
    background: var(--accent-soft);
    text-align: center;
    overflow: hidden;
    margin-bottom: 15px;
}

.class-date span {
    display: block;
    background: var(--accent);
    color: #fff;
    font-size: 12px;
    padding: 4px;
    text-transform: uppercase;
}

.class-date strong {
    display: block;
    color: var(--accent-dark);
    font-size: 26px;
    padding: 7px 0 9px;
}

.class-info > small,
.muted-text {
    color: var(--muted);
}

.class-info h3 {
    margin: 4px 0 2px;
    font-size: 18px;
}

.class-info p {
    margin: 3px 0;
    font-size: 13px;
}

.class-meta {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 0;
    border: 1px solid var(--border);
    border-radius: 10px;
    margin: 17px 0;
    overflow: hidden;
}

.class-meta div {
    padding: 9px 10px;
    border-bottom: 1px solid var(--border);
}

.class-meta div:nth-last-child(-n+2) {
    border-bottom: 0;
}

.class-meta div:nth-child(odd) {
    border-right: 1px solid var(--border);
}

.class-meta dt {
    color: var(--muted);
    font-size: 11px;
}

.class-meta dd {
    margin: 2px 0 0;
    font-size: 13px;
    font-weight: 600;
}

.primary-button {
    width: 100%;
    border: 0;
    border-radius: 10px;
    padding: 11px 14px;
    background: var(--accent);
    color: #fff;
    font-weight: 650;
    cursor: pointer;
    text-align: center;
}

.primary-button:hover {
    background: var(--accent-dark);
}

.button-link {
    display: block;
    text-decoration: none;
}

.activity-list {
    margin: -4px 0;
}

.activity-row {
    display: grid;
    grid-template-columns: 34px minmax(0, 1fr);
    gap: 11px;
    padding: 13px 0;
    border-top: 1px solid var(--border);
}

.activity-row:first-child {
    border-top: 0;
}

.activity-row p {
    margin: 1px 0 2px;
    font-size: 13px;
}

.activity-row small {
    color: var(--muted);
    font-size: 11px;
}

.quick-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 10px;
}

.quick-action {
    border: 1px solid var(--border);
    background: var(--surface);
    border-radius: 11px;
    padding: 13px;
    text-align: left;
    cursor: pointer;
    min-height: 105px;
}

.quick-action:hover {
    background: var(--surface-soft);
    border-color: #cfd7e4;
}

.quick-action > span {
    display: block;
    color: var(--accent);
    font-size: 20px;
    margin-bottom: 7px;
}

.quick-action strong,
.quick-action small {
    display: block;
}

.quick-action strong {
    font-size: 13px;
}

.quick-action small {
    color: var(--muted);
    font-size: 11px;
    margin-top: 3px;
}

.empty-state {
    border: 1px dashed #cfd6e0;
    background: var(--surface-soft);
    border-radius: 11px;
    padding: 22px;
    text-align: center;
    color: var(--muted);
}

.empty-state strong {
    color: var(--text);
    font-size: 14px;
}

.empty-state p {
    margin: 5px 0 0;
    font-size: 12px;
}

/* Login y setup */
.login-page {
    min-height: 100vh;
    display: grid;
    place-items: center;
    padding: 24px;
    background:
        radial-gradient(circle at top left, #eef3fb 0, transparent 35%),
        var(--bg);
}

.login-shell {
    width: min(100%, 440px);
}

.login-card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 18px;
    padding: 28px;
    box-shadow: 0 18px 55px rgba(31, 42, 68, .09);
}

.setup-card {
    width: min(100vw - 48px, 560px);
}

.login-brand {
    display: flex;
    align-items: center;
    gap: 11px;
    margin-bottom: 30px;
}

.login-heading {
    margin-bottom: 22px;
}

.login-heading h1 {
    margin: 0 0 4px;
    font-size: 24px;
}

.login-heading p {
    margin: 0;
    color: var(--muted);
    font-size: 13px;
}

.stack-form {
    display: grid;
    gap: 15px;
}

.stack-form label > span {
    display: block;
    font-size: 12px;
    font-weight: 650;
    margin-bottom: 6px;
}

.stack-form input {
    width: 100%;
    border: 1px solid #d7dce5;
    background: #fff;
    color: var(--text);
    border-radius: 9px;
    padding: 11px 12px;
    outline: none;
}

.stack-form input:focus {
    border-color: var(--accent);
    box-shadow: 0 0 0 3px var(--accent-soft);
}

.two-cols {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 12px;
}

.alert {
    border-radius: 9px;
    padding: 10px 12px;
    font-size: 13px;
    margin-bottom: 15px;
}

.alert.error {
    background: var(--danger-soft);
    color: var(--danger);
    border: 1px solid #f1caca;
}

.alert.success {
    background: var(--success-soft);
    color: var(--success);
    border: 1px solid #cce9da;
}

.login-help,
.security-note {
    color: var(--muted);
    font-size: 11px;
    margin: 18px 0 0;
}

.security-note {
    padding: 10px;
    background: #fff8e6;
    border-radius: 8px;
    color: #735b18;
}

@media (max-width: 1100px) {
    .metric-grid {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }

    .dashboard-grid,
    .lower-grid {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 760px) {
    .app-shell {
        display: block;
    }

    .sidebar {
        position: fixed;
        left: -270px;
        width: 245px;
        transition: left .2s ease;
        box-shadow: 12px 0 30px rgba(0, 0, 0, .08);
    }

    .sidebar.open {
        left: 0;
    }

    .mobile-menu {
        display: block;
    }

    .topbar {
        padding: 12px 16px;
    }

    .content {
        padding: 18px 14px 34px;
    }

    .metric-grid {
        grid-template-columns: 1fr 1fr;
        gap: 10px;
    }

    .metric-card {
        align-items: flex-start;
        padding: 14px;
    }

    .metric-icon {
        display: none;
    }

    .metric-card strong {
        font-size: 24px;
    }

    .panel {
        padding: 16px;
    }
}

@media (max-width: 480px) {
    .metric-grid {
        grid-template-columns: 1fr;
    }

    .quick-grid,
    .two-cols {
        grid-template-columns: 1fr;
    }

    .class-meta {
        grid-template-columns: 1fr;
    }

    .class-meta div,
    .class-meta div:nth-child(odd) {
        border-right: 0;
        border-bottom: 1px solid var(--border);
    }

    .class-meta div:last-child {
        border-bottom: 0;
    }

    .login-card {
        padding: 22px 18px;
    }
}

.language-switch {
    display: inline-flex;
    align-items: center;
    gap: 3px;
    padding: 3px;
    margin-left: auto;
    margin-right: 12px;
    border: 1px solid var(--border);
    background: var(--surface-soft);
    border-radius: 9px;
}

.language-switch a {
    min-width: 38px;
    padding: 6px 8px;
    border-radius: 7px;
    text-decoration: none;
    text-align: center;
    color: var(--muted);
    font-size: 12px;
    font-weight: 700;
}

.language-switch a.active {
    background: var(--accent);
    color: #fff;
}

.language-switch a:hover:not(.active) {
    color: var(--text);
    background: var(--surface);
}


/* Courses module */
.page-heading-row,
.course-detail-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    gap: 18px;
    margin-bottom: 20px;
}

.page-heading-row h2,
.course-detail-header h2 {
    margin: 4px 0 4px;
    font-size: 24px;
}

.page-heading-row p,
.course-detail-header p {
    margin: 0;
    color: var(--muted);
    font-size: 13px;
}

.compact-button {
    width: auto;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    text-decoration: none;
    white-space: nowrap;
}

.button-link-inline {
    text-decoration: none;
    display: inline-flex;
    align-items: center;
}

.secondary-button {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    border: 1px solid var(--border);
    background: var(--surface);
    color: var(--text);
    border-radius: 9px;
    padding: 9px 12px;
    text-decoration: none;
    cursor: pointer;
}

.secondary-button:hover {
    background: var(--surface-soft);
}

.course-stat-grid,
.course-detail-metrics {
    display: grid;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 12px;
    margin-bottom: 20px;
}

.mini-stat {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 15px 16px;
}

.mini-stat span,
.mini-stat strong {
    display: block;
}

.mini-stat span {
    color: var(--muted);
    font-size: 12px;
}

.mini-stat strong {
    margin-top: 2px;
    font-size: 22px;
}

.course-filter-panel {
    margin-bottom: 16px;
}

.course-filter-form {
    display: grid;
    grid-template-columns: minmax(220px, 1fr) 210px auto;
    align-items: end;
    gap: 12px;
}

.course-filter-form label > span,
.form-field > span,
.form-grid label > span {
    display: block;
    font-size: 12px;
    font-weight: 650;
    margin-bottom: 6px;
}

.course-filter-form input,
.course-filter-form select,
.course-form input,
.course-form select,
.course-form textarea,
.stack-form select {
    width: 100%;
    border: 1px solid #d7dce5;
    background: #fff;
    color: var(--text);
    border-radius: 9px;
    padding: 10px 11px;
    outline: none;
}

.course-form textarea {
    resize: vertical;
    min-height: 145px;
}

.course-filter-form input:focus,
.course-filter-form select:focus,
.course-form input:focus,
.course-form select:focus,
.course-form textarea:focus,
.stack-form select:focus {
    border-color: var(--accent);
    box-shadow: 0 0 0 3px var(--accent-soft);
}

.filter-actions {
    display: flex;
    gap: 8px;
}

.course-list {
    display: grid;
    gap: 13px;
}

.course-card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 14px;
    padding: 18px;
    display: grid;
    grid-template-columns: minmax(0, 1fr) auto;
    gap: 18px;
    box-shadow: var(--shadow);
}

.course-card-heading {
    display: flex;
    justify-content: space-between;
    gap: 14px;
    align-items: flex-start;
}

.course-card h3 {
    margin: 3px 0 0;
    font-size: 17px;
}

.course-card h3 a {
    text-decoration: none;
}

.course-card h3 a:hover {
    color: var(--accent);
}

.course-code {
    display: inline-block;
    color: var(--accent);
    background: var(--accent-soft);
    border-radius: 6px;
    padding: 3px 7px;
    font-size: 11px;
    font-weight: 750;
    letter-spacing: .05em;
}

.course-description {
    color: var(--muted);
    font-size: 13px;
    margin: 10px 0 14px;
    max-width: 900px;
}

.course-meta-grid {
    display: flex;
    flex-wrap: wrap;
    gap: 9px 22px;
}

.course-meta-grid div {
    min-width: 85px;
}

.course-meta-grid span,
.course-meta-grid strong {
    display: block;
}

.course-meta-grid span {
    color: var(--muted);
    font-size: 10px;
    text-transform: uppercase;
    letter-spacing: .04em;
}

.course-meta-grid strong {
    margin-top: 1px;
    font-size: 13px;
}

.course-card-actions,
.course-detail-actions {
    display: flex;
    gap: 8px;
    align-items: flex-start;
    flex-wrap: wrap;
}

.status-badge {
    display: inline-flex;
    align-items: center;
    border-radius: 999px;
    padding: 4px 8px;
    font-size: 11px;
    font-weight: 700;
    white-space: nowrap;
}

.status-draft {
    background: #f1f3f6;
    color: #626b78;
}

.status-active {
    background: #eef4ff;
    color: #315ca8;
}

.status-published {
    background: var(--success-soft);
    color: var(--success);
}

.status-archived {
    background: #f7f1ea;
    color: #765b3a;
}

.empty-action {
    margin-top: 13px;
}

.back-link {
    display: inline-block;
    color: var(--accent);
    text-decoration: none;
    font-size: 12px;
    margin-bottom: 6px;
}

.course-form {
    display: grid;
    gap: 18px;
}

.form-section {
    display: grid;
    gap: 16px;
}

.section-heading {
    border-bottom: 1px solid var(--border);
    padding-bottom: 10px;
}

.section-heading h3 {
    margin: 0;
    font-size: 15px;
}

.section-heading.with-language {
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.language-chip {
    display: inline-grid;
    place-items: center;
    min-width: 34px;
    height: 28px;
    border-radius: 7px;
    background: var(--accent-soft);
    color: var(--accent);
    font-size: 11px;
    font-weight: 800;
}

.form-grid {
    display: grid;
    gap: 14px;
}

.two-field-grid {
    grid-template-columns: 1fr 1fr;
}

.form-field,
.form-grid label {
    display: block;
}

.form-field > small,
.form-grid label > small {
    display: block;
    margin-top: 5px;
    color: var(--muted);
    font-size: 11px;
}

.field-error {
    display: block;
    margin-top: 5px;
    color: var(--danger);
    font-size: 11px;
    font-style: normal;
}

.bilingual-form-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 18px;
}

.form-actions {
    display: flex;
    justify-content: flex-end;
    gap: 10px;
}

.sticky-form-actions {
    position: sticky;
    bottom: 10px;
    background: rgba(245, 247, 251, .94);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 10px;
    z-index: 6;
    backdrop-filter: blur(8px);
}

.course-detail-subline {
    display: flex;
    align-items: center;
    gap: 10px;
    color: var(--muted);
    font-size: 12px;
    margin-top: 7px;
    flex-wrap: wrap;
}

.course-detail-grid {
    display: grid;
    grid-template-columns: minmax(0, 1.4fr) minmax(280px, .6fr);
    gap: 18px;
    margin-bottom: 20px;
}

.course-long-description {
    font-size: 14px;
    line-height: 1.7;
    white-space: normal;
}

.detail-list {
    margin: 20px 0 0;
    border-top: 1px solid var(--border);
}

.detail-list div {
    display: grid;
    grid-template-columns: 150px 1fr;
    gap: 12px;
    padding: 10px 0;
    border-bottom: 1px solid var(--border);
}

.detail-list dt {
    color: var(--muted);
    font-size: 12px;
}

.detail-list dd {
    margin: 0;
    font-size: 13px;
}

.structure-preview {
    display: grid;
    grid-template-columns: minmax(0, 1fr) auto minmax(0, .6fr) auto minmax(0, .6fr);
    gap: 12px;
    align-items: center;
}

.structure-node {
    border: 1px solid var(--border);
    border-radius: 11px;
    padding: 14px;
    background: var(--surface-soft);
}

.structure-node span,
.structure-node strong {
    display: block;
}

.structure-node span {
    color: var(--muted);
    font-size: 11px;
}

.structure-node strong {
    margin-top: 3px;
    font-size: 14px;
}

.structure-arrow {
    color: var(--accent);
    font-weight: 800;
}

.quick-action-link {
    text-decoration: none;
    color: inherit;
}

@media (max-width: 960px) {
    .course-stat-grid,
    .course-detail-metrics {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }

    .course-filter-form {
        grid-template-columns: 1fr 1fr;
    }

    .filter-actions {
        grid-column: 1 / -1;
    }

    .bilingual-form-grid,
    .course-detail-grid {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 650px) {
    .page-heading-row,
    .course-detail-header {
        display: grid;
    }

    .page-heading-row .primary-button,
    .course-detail-actions .primary-button {
        width: 100%;
    }

    .course-filter-form,
    .two-field-grid {
        grid-template-columns: 1fr;
    }

    .filter-actions {
        grid-column: auto;
    }

    .course-card {
        grid-template-columns: 1fr;
    }

    .course-card-actions {
        border-top: 1px solid var(--border);
        padding-top: 12px;
    }

    .course-card-actions .secondary-button {
        flex: 1;
    }

    .structure-preview {
        grid-template-columns: 1fr;
    }

    .structure-arrow {
        transform: rotate(90deg);
        justify-self: center;
    }
}

@media (max-width: 420px) {
    .course-stat-grid,
    .course-detail-metrics {
        grid-template-columns: 1fr 1fr;
    }

    .course-card-heading {
        display: grid;
    }

    .detail-list div {
        grid-template-columns: 1fr;
        gap: 3px;
    }
}