/* VPCARS Education — базовые стили */
:root {
    --color-bg: #f4f6f9;
    --color-surface: #fff;
    --color-text: #1a1d26;
    --color-muted: #6b7280;
    --color-primary: #2563eb;
    --color-primary-hover: #1d4ed8;
    --color-danger: #dc2626;
    --color-border: #e5e7eb;
    --radius: 8px;
    --shadow: 0 1px 3px rgba(0, 0, 0, 0.08);
    --font: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}

* {
    box-sizing: border-box;
}

body {
    margin: 0;
    font-family: var(--font);
    font-size: 16px;
    line-height: 1.5;
    color: var(--color-text);
    background: var(--color-bg);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.container {
    width: 100%;
    max-width: 960px;
    margin: 0 auto;
    padding: 0 1rem;
}

.site-header {
    background: var(--color-surface);
    border-bottom: 1px solid var(--color-border);
    box-shadow: var(--shadow);
}

.header-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0.75rem 1rem;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.logo {
    font-weight: 700;
    color: var(--color-primary);
    text-decoration: none;
}

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

.main-nav a {
    color: var(--color-text);
    text-decoration: none;
    font-size: 0.95rem;
}

.main-nav a:hover {
    color: var(--color-primary);
}

.main-content {
    flex: 1;
    padding: 1.5rem 1rem 2rem;
}

.site-footer {
    background: var(--color-surface);
    border-top: 1px solid var(--color-border);
    padding: 1rem;
    text-align: center;
    font-size: 0.875rem;
    color: var(--color-muted);
}

h1 {
    font-size: 1.5rem;
    margin: 0 0 1rem;
}

h2 {
    font-size: 1.15rem;
    margin: 0 0 0.75rem;
}

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

.empty-state {
    color: var(--color-muted);
    padding: 2rem;
    text-align: center;
    background: var(--color-surface);
    border-radius: var(--radius);
}

/* Формы */
.form label {
    display: block;
    margin-bottom: 1rem;
    font-size: 0.9rem;
}

.form input[type="text"],
.form input[type="password"],
.form input[type="email"],
.form input[type="number"],
.form input[type="datetime-local"],
.form select,
.form textarea {
    display: block;
    width: 100%;
    margin-top: 0.35rem;
    padding: 0.5rem 0.65rem;
    border: 1px solid var(--color-border);
    border-radius: var(--radius);
    font: inherit;
}

.form-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: 0 1rem;
}

.form-grid .full-width {
    grid-column: 1 / -1;
}

.checkbox-label {
    display: flex !important;
    align-items: center;
    gap: 0.5rem;
}

.checkbox-label input {
    width: auto;
    margin: 0;
}

.btn {
    display: inline-block;
    padding: 0.5rem 1rem;
    border: none;
    border-radius: var(--radius);
    font: inherit;
    cursor: pointer;
    text-decoration: none;
    text-align: center;
}

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

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

.btn-secondary {
    background: var(--color-border);
    color: var(--color-text);
}

.btn-link {
    background: none;
    border: none;
    color: var(--color-primary);
    cursor: pointer;
    padding: 0;
    font: inherit;
    text-decoration: underline;
}

.btn-link.danger {
    color: var(--color-danger);
}

.alert {
    padding: 0.75rem 1rem;
    border-radius: var(--radius);
    margin-bottom: 1rem;
}

.alert-success {
    background: #d1fae5;
    color: #065f46;
}

.alert-error {
    background: #fee2e2;
    color: #991b1b;
}

.alert-info {
    background: #dbeafe;
    color: #1e40af;
}

.alert-info a {
    color: #1d4ed8;
    font-weight: 600;
}

.admin-banner {
    margin-bottom: 1.25rem;
}

.nav-admin {
    font-weight: 600;
    color: var(--color-primary) !important;
}

.action-cards {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
    gap: 1rem;
    margin-bottom: 2rem;
}

.action-card {
    display: flex;
    flex-direction: column;
    gap: 0.35rem;
    padding: 1.25rem;
    background: var(--color-surface);
    border: 2px solid var(--color-primary);
    border-radius: var(--radius);
    text-decoration: none;
    color: inherit;
    box-shadow: var(--shadow);
    transition: transform 0.15s, box-shadow 0.15s;
}

.action-card:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(37, 99, 235, 0.2);
}

.action-card strong {
    font-size: 1.05rem;
    color: var(--color-primary);
}

.action-card span:last-child {
    font-size: 0.85rem;
    color: var(--color-muted);
}

.action-icon {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--color-primary);
    line-height: 1;
}

.auth-card {
    max-width: 400px;
    margin: 2rem auto;
    padding: 2rem;
    background: var(--color-surface);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
}

/* Список уроков */
.lesson-list {
    list-style: none;
    padding: 0;
    margin: 0;
    display: grid;
    gap: 1rem;
}

.lesson-card {
    background: var(--color-surface);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
}

.lesson-card a {
    display: block;
    padding: 1.25rem;
    text-decoration: none;
    color: inherit;
}

.lesson-card h2 {
    margin: 0 0 0.5rem;
    font-size: 1.1rem;
    color: var(--color-primary);
}

.lesson-card p {
    margin: 0;
    color: var(--color-muted);
    font-size: 0.9rem;
}

.back-link {
    margin-bottom: 1rem;
}

.lesson-description {
    margin-bottom: 1.5rem;
    padding: 1rem;
    background: var(--color-surface);
    border-radius: var(--radius);
}

.media-block {
    background: var(--color-surface);
    padding: 1rem;
    border-radius: var(--radius);
    margin-bottom: 1rem;
    box-shadow: var(--shadow);
}

.media-block h3 {
    margin: 0 0 0.25rem;
    font-size: 1rem;
}

.media-meta {
    font-size: 0.85rem;
    color: var(--color-muted);
    margin: 0 0 0.75rem;
}

.edu-player {
    width: 100%;
    max-height: 480px;
    background: #000;
    border-radius: 4px;
}

/* Админка */
.admin-layout .main-content {
    max-width: 1100px;
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
    gap: 1rem;
    margin-bottom: 2rem;
}

.stat-card {
    background: var(--color-surface);
    padding: 1.25rem;
    border-radius: var(--radius);
    text-align: center;
    box-shadow: var(--shadow);
}

.stat-num {
    display: block;
    font-size: 2rem;
    font-weight: 700;
    color: var(--color-primary);
}

.admin-links {
    list-style: none;
    padding: 0;
}

.admin-links li {
    margin-bottom: 0.5rem;
}

.admin-links a {
    color: var(--color-primary);
}

.admin-section {
    background: var(--color-surface);
    padding: 1.25rem;
    border-radius: var(--radius);
    margin-bottom: 1.5rem;
    box-shadow: var(--shadow);
}

.data-table {
    width: 100%;
    border-collapse: collapse;
    font-size: 0.9rem;
}

.data-table th,
.data-table td {
    padding: 0.5rem 0.65rem;
    border-bottom: 1px solid var(--color-border);
    text-align: left;
    vertical-align: top;
}

.data-table th {
    background: var(--color-bg);
    font-weight: 600;
}

.actions {
    white-space: nowrap;
}

.actions a {
    margin-right: 0.5rem;
    color: var(--color-primary);
}

.inline-form {
    display: inline;
}

.input-narrow {
    width: 4rem;
}

.row-expired {
    opacity: 0.6;
}

.drop-zone {
    border: 2px dashed var(--color-border);
    border-radius: var(--radius);
    padding: 2rem;
    text-align: center;
    margin-bottom: 1rem;
    transition: border-color 0.2s, background 0.2s;
}

.drop-zone.dragover {
    border-color: var(--color-primary);
    background: #eff6ff;
}

.drop-zone input[type="file"] {
    margin-top: 0.5rem;
}

/* Защита контента (UX) */
.protected-content {
    user-select: none;
    -webkit-user-select: none;
}

@media (max-width: 640px) {
    .data-table {
        font-size: 0.8rem;
    }

    .header-inner {
        flex-direction: column;
        align-items: flex-start;
    }
}