:root {
    --primary-color: #1a73e8;
    --background-color: #f8f9fa;
    --card-background: #ffffff;
    --text-color: #333333;
}

body {
    margin: 0;
    padding: 0;
    font-family: 'Helvetica Neue', Arial, sans-serif;
    background-color: var(--background-color);
}

header {
    background-color: white;
    padding: 0;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

.filter-buttons {
    text-align: center;
    margin: 30px 0;
    padding: 20px 0;
    background-color: white;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

.search-container {
    max-width: 600px;
    margin: 20px auto;
}

#searchInput {
    width: 100%;
    padding: 12px;
    border: 1px solid #ddd;
    border-radius: 8px;
    font-size: 16px;
}

.filter-buttons {
    text-align: center;
    margin: 20px 0;
}

.filter-btn {
    padding: 8px 16px;
    margin: 0 8px;
    border: none;
    border-radius: 20px;
    background-color: var(--primary-color);
    color: white;
    cursor: pointer;
    transition: background-color 0.3s;
}

.cource-gallery-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(400px, 2fr));
    gap: 24px;
    padding: 24px;
}

.thumbnail-poster img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.gallery-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 24px;
    padding: 24px;
}

.course-card {
    background-color: var(--card-background);
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 2px 8px rgba(0,0,0,0.1);
    transition: transform 0.3s;
}

.course-card:hover {
    transform: translateY(-4px);
}

.thumbnail img {
    width: 100%;
    height: 200px;
    object-fit: cover;
}

.course-info {
    padding: 16px;
}

.course-index-info {
    padding: 16px;
    display: flex;
    justify-content: center;
    align-items: center;
}


.tags {
    margin-top: 12px;
}

.tag {
    display: inline-block;
    padding: 4px 8px;
    margin-right: 8px;
    background-color: #e8f0fe;
    color: var(--primary-color);
    border-radius: 16px;
    font-size: 12px;
}


/* 講座ページのスタイル */
.course-container {
    max-width: 800px;
    margin: 40px auto;
    padding: 20px;
}

.course-header {
    text-align: center;
    margin-bottom: 40px;
}

.course-title {
    font-size: 2.5em;
    color: var(--primary-color);
    margin-bottom: 10px;
}

.course-subtitle {
    font-size: 1.2em;
    color: #666;
    margin-bottom: 20px;
}

.course-meta {
    display: flex;
    justify-content: center;
    gap: 20px;
    color: #666;
    margin-bottom: 30px;
}

.video-container {
    position: relative;
    padding-bottom: 56.25%;
    height: 0;
    overflow: hidden;
    margin-bottom: 30px;
    border-radius: 12px;
    box-shadow: 0 4px 12px rgba(0,0,0,0.1);
}

.video-container iframe {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    border: none;
}

.back-button {
    display: inline-block;
    padding: 10px 20px;
    background-color: var(--primary-color);
    color: white;
    text-decoration: none;
    border-radius: 20px;
    margin-bottom: 20px;
    transition: background-color 0.3s;
}

.back-button:hover {
    background-color: #1557b0;
}

.content-center {
    display: flex;
    flex-direction: column;
    align-items: center;
    margin: 10px 0;
}

.thumbnail {
    width: 100%;
    max-width: 640px;
    height: auto;
    border-radius: 10px;
    margin-bottom: 20px;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
}

/* カスタムダウンロードボタン */
.custom-button {
    display: inline-block;
    padding: 15px 30px;
    background: linear-gradient(135deg, #6e8efb, #4a6cf7);
    color: white;
    text-decoration: none;
    border-radius: 50px;
    font-weight: 600;
    box-shadow: 0 4px 15px rgba(74, 108, 247, 0.2);
    transition: all 0.3s ease;
    margin: 5px 0;
    font-size: 16px;
    text-align: center;
}

.custom-button:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(74, 108, 247, 0.4);
    background: linear-gradient(135deg, #4a6cf7, #6e8efb);
}

.custom-button i {
    margin-right: 8px;
}

.header-content {
    display: flex;
    align-items: flex-start;
    padding: 20px;
}

.header-icon {
    width: 100%;
    height: 64px;
    object-fit: contain;
    margin-left: 10px;
}

.google-form h2 {
    text-align: center;
    margin: 20px 0;
}

.google-form p {
    text-align: center;
    margin: 15px 0;
}

.google-form iframe {
    margin: 0 auto;
    width: 100%;
    height: 1620px;
}

.wrapper{
    min-height: 100vh;
    position: relative;/*←相対位置*/
}

.footer-content {
    width: 100%;
    background-color: #111111;
    color: #fff;
    text-align: center;
    padding: 10px 0;

    position: absolute;/*←絶対位置*/
    bottom: 0; /*下に固定*/
}


.help-link {
    margin: 10px 0;
    text-align: center;
}

.help-link a {
    color: #666;
    text-decoration: none;
    font-size: 0.9em;
    transition: color 0.3s ease;
    display: inline-flex;
    align-items: center;
    gap: 5px;
}

.help-link a:hover {
    color: #007bff;
}

.help-link i {
    font-size: 1.1em;
}