:root {
    --primary: #1f6feb;
    --secondary: #555;
    --danger: #d93025;
    --success: #107c41;
    --warning: #b08900;
    --tag-level: #1f6feb;
    --tag-discipline: #7c3aed;
    --tag-type: #16a34a;
    --tag-theme: #f97316;
    --bg: #f5f7fb;
    --text: #1d1d1f;
    --radius: 8px;
}

* {
    box-sizing: border-box;
}

body {
    margin: 0;
    font-family: 'Segoe UI', Roboto, sans-serif;
    background: var(--bg);
    color: var(--text);
}

a {
    color: var(--primary);
    text-decoration: none;
}

a:hover {
    text-decoration: underline;
}

.container {
    width: min(1100px, 92vw);
    margin: 0 auto;
    padding: 1.5rem 0;
}

.site-header {
    background: #fff;
    border-bottom: 1px solid #e4e6ef;
}

.site-header .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1rem;
}

.logo a {
    font-weight: 700;
    font-size: 1.4rem;
}

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

.nav-home {
    margin-left: auto;
}

.nav-user {
    font-size: 0.9rem;
    color: var(--secondary);
}

main.container {
    padding-bottom: 3rem;
}

.site-footer {
    background: #14161a;
    color: #fff;
    text-align: center;
    padding: 1.5rem 0;
}

.btn {
    display: inline-block;
    border: none;
    padding: 0.6rem 1.2rem;
    border-radius: var(--radius);
    cursor: pointer;
    font-weight: 600;
    text-decoration: none;
}

.btn-primary {
    background: var(--primary);
    color: #fff;
}

.btn-secondary {
    background: #fff;
    color: var(--primary);
    border: 1px solid var(--primary);
}

.btn-danger {
    background: var(--danger);
    color: #fff;
}

.alert {
    padding: 0.8rem 1rem;
    border-radius: var(--radius);
    margin-bottom: 1rem;
}

.alert-success {
    background: rgba(16, 124, 65, 0.12);
    color: var(--success);
}

.alert-danger {
    background: rgba(217, 48, 37, 0.12);
    color: var(--danger);
}

.page-header h2 {
    margin-bottom: 0.2rem;
}

.page-header p {
    margin-top: 0;
    color: var(--secondary);
}

.filter-form {
    background: #fff;
    padding: 1rem;
    border-radius: var(--radius);
    box-shadow: 0 5px 20px rgba(15, 23, 42, 0.08);
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.filter-form .grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
    gap: 1rem;
}

.filter-form label {
    font-size: 0.9rem;
    display: flex;
    flex-direction: column;
    gap: 0.3rem;
    color: var(--secondary);
}

.filter-form select,
.filter-form input[type="search"],
.form input[type="text"],
.form input[type="password"],
.form input[type="url"],
.form input[type="file"],
.form textarea,
.form select {
    padding: 0.6rem;
    border-radius: var(--radius);
    border: 1px solid #d0d5e4;
    font-size: 1rem;
}

.filter-form .actions {
    display: flex;
    flex-wrap: wrap;
    gap: 0.8rem;
    align-items: center;
}

.checkbox-inline {
    display: flex;
    align-items: center;
    gap: 0.4rem;
    font-size: 0.9rem;
    color: var(--secondary);
}

.cards {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 1.5rem;
    margin-top: 1.5rem;
}

.card,
.resource-detail,
.form,
.table-card,
.admin-form .form,
.admin-list table {
    background: #fff;
    border-radius: var(--radius);
    padding: 1rem;
    box-shadow: 0 5px 20px rgba(15, 23, 42, 0.06);
}

.resource-layout {
    display: grid;
    grid-template-columns: minmax(240px, 320px) minmax(0, 1fr);
    gap: 2rem;
    align-items: flex-start;
}

.resource-info header {
    margin-bottom: 1.5rem;
}

.resource-info section + section {
    margin-top: 1.5rem;
}

.resource-main {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.resource-viewer {
    margin-top: 1.5rem;
}

.resource-viewer-frame {
    position: relative;
    width: 100%;
    aspect-ratio: 2 / 3;
    min-height: 360px;
    max-height: min(85vh, 960px);
    border: 1px solid #d0d5e4;
    border-radius: var(--radius);
    background: #f8fafc;
    overflow: hidden;
    box-shadow: 0 5px 20px rgba(15, 23, 42, 0.06);
}

@supports not (aspect-ratio: 1 / 1) {
    .resource-viewer-frame::before {
        content: "";
        display: block;
        padding-top: 150%;
    }

    .resource-viewer-frame > * {
        position: absolute;
        inset: 0;
    }
}

.resource-viewer-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1rem;
    margin-bottom: 1rem;
}

.resource-viewer-content {
    display: flex;
    flex-direction: column;
    gap: 1rem;
    position: relative;
}

.resource-viewer-empty {
    min-height: 200px;
    display: flex;
    flex-direction: column;
    justify-content: center;
    gap: 1rem;
}

.resource-viewer-content:fullscreen {
    background: #000;
    padding: 1rem;
    justify-content: center;
}

.resource-viewer-content:fullscreen iframe,
.resource-viewer-content:fullscreen video,
.resource-viewer-content:fullscreen img,
.resource-viewer-content:fullscreen embed,
.resource-viewer-content:fullscreen object {
    width: 100%;
    height: 100%;
    max-height: 100%;
    object-fit: contain;
}

.resource-viewer-content:fullscreen .resource-viewer-frame {
    height: 100%;
}

.resource-viewer-frame iframe,
.resource-viewer-frame embed,
.resource-viewer-frame object {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
    border: 0;
    background: transparent;
}

.resource-viewer iframe,
.resource-viewer embed {
    width: 100%;
    height: 100%;
    min-height: 100%;
}

.resource-viewer-media {
    display: flex;
    justify-content: center;
}

.resource-viewer-media img,
.resource-viewer-media video {
    max-width: 100%;
    border-radius: var(--radius);
    box-shadow: 0 4px 16px rgba(15, 23, 42, 0.08);
}

.resource-viewer-media video {
    width: 100%;
}

.resource-viewer-media audio {
    width: 100%;
    margin-top: 0.5rem;
}

.resource-viewer-fallback {
    margin-top: 0.75rem;
    text-align: center;
}

.resource-viewer-fallback a {
    color: var(--primary);
    font-weight: 600;
}

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

    .resource-viewer-header {
        flex-direction: column;
        align-items: flex-start;
        gap: 0.75rem;
    }

    .viewer-fullscreen-button,
    .resource-viewer-header .btn {
        width: 100%;
    }
}

.card-private {
    border: 1px solid rgba(176, 137, 0, 0.4);
}

.card h3 {
    margin-top: 0;
}

.card p {
    margin-bottom: 0.6rem;
}

.tag-list {
    display: flex;
    flex-wrap: wrap;
    gap: 0.4rem;
    margin-bottom: 0.6rem;
}

.meta {
    font-size: 0.85rem;
    color: var(--secondary);
}

.badge {
    display: inline-block;
    padding: 0.2rem 0.6rem;
    border-radius: var(--radius);
    font-size: 0.75rem;
    font-weight: 600;
}

.badge-success {
    background: rgba(16, 124, 65, 0.15);
    color: var(--success);
}

.badge-warning {
    background: rgba(176, 137, 0, 0.2);
    color: var(--warning);
}

.badge-level {
    background: rgba(31, 111, 235, 0.15);
    color: var(--tag-level);
}

.badge-discipline {
    background: rgba(124, 58, 237, 0.15);
    color: var(--tag-discipline);
}

.badge-type {
    background: rgba(22, 163, 74, 0.15);
    color: var(--tag-type);
}

.badge-theme {
    background: rgba(249, 115, 22, 0.15);
    color: var(--tag-theme);
}

.form {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.form .grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 1rem;
}

.form textarea {
    resize: vertical;
}

.admin-list table {
    width: 100%;
    border-collapse: collapse;
    margin-top: 1rem;
}

.admin-list th,
.admin-list td {
    text-align: left;
    padding: 0.6rem;
    border-bottom: 1px solid #e4e6ef;
}

.admin-list tr:last-child td {
    border-bottom: none;
}

.auth-form {
    max-width: 420px;
    margin: 0 auto;
}

.help {
    font-size: 0.85rem;
    color: var(--secondary);
}

@media (max-width: 600px) {
    .main-nav {
        flex-direction: column;
        align-items: flex-start;
    }

    .filter-form .actions {
        flex-direction: column;
        align-items: stretch;
    }

    .btn,
    .filter-form .actions .btn,
    .filter-form .actions a {
        width: 100%;
        text-align: center;
    }
}