*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    background: #f5f5f5;
    color: #1a1a1a;
    line-height: 1.6;
    min-height: 100dvh;
}

main {
    max-width: 540px;
    margin: 0 auto;
    padding: 2rem 1rem;
}

.card {
    background: #fff;
    border-radius: 12px;
    padding: 2rem;
    box-shadow: 0 1px 3px rgba(0,0,0,0.1);
}

h1 {
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: 0.25rem;
}

.speakers {
    color: #666;
    margin-bottom: 2rem;
    font-size: 0.95rem;
}

fieldset.rating-group {
    border: none;
    margin-bottom: 1.5rem;
}

fieldset.rating-group legend {
    font-weight: 600;
    font-size: 0.95rem;
    margin-bottom: 0.5rem;
    display: block;
}

.rating-buttons {
    display: flex;
    gap: 0;
}

.rating-buttons input[type="radio"] {
    position: absolute;
    opacity: 0;
    width: 0;
    height: 0;
}

.rating-buttons label {
    flex: 1;
    text-align: center;
    padding: 0.6rem 0;
    cursor: pointer;
    border: 1px solid #ddd;
    background: #fafafa;
    font-weight: 500;
    font-size: 0.95rem;
    transition: background 0.15s, color 0.15s, border-color 0.15s;
    user-select: none;
}

.rating-buttons label:first-of-type {
    border-radius: 8px 0 0 8px;
}

.rating-buttons label:last-of-type {
    border-radius: 0 8px 8px 0;
}

.rating-buttons label:not(:first-of-type) {
    border-left: none;
}

.rating-buttons input[type="radio"]:checked + label {
    background: #2563eb;
    color: #fff;
    border-color: #2563eb;
}

.rating-buttons input[type="radio"]:checked + label + label {
    border-left-color: #2563eb;
}

.comment-group {
    margin-bottom: 1.5rem;
}

.comment-group label {
    display: block;
    font-weight: 600;
    font-size: 0.95rem;
    margin-bottom: 0.5rem;
}

.comment-group textarea {
    width: 100%;
    border: 1px solid #ddd;
    border-radius: 8px;
    padding: 0.75rem;
    font-family: inherit;
    font-size: 0.95rem;
    resize: vertical;
    line-height: 1.5;
}

.comment-group textarea:focus {
    outline: none;
    border-color: #2563eb;
    box-shadow: 0 0 0 3px rgba(37,99,235,0.1);
}

button[type="submit"] {
    width: 100%;
    padding: 0.85rem;
    background: #2563eb;
    color: #fff;
    border: none;
    border-radius: 8px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: background 0.15s;
}

button[type="submit"]:hover {
    background: #1d4ed8;
}

button[type="submit"]:disabled {
    background: #93b4f5;
    cursor: not-allowed;
}

.error-message {
    color: #dc2626;
    font-size: 0.9rem;
    margin-top: 1rem;
    text-align: center;
    min-height: 0;
}

.error-message:empty {
    display: none;
}

.thank-you {
    text-align: center;
    padding: 3rem 2rem;
}

.thank-you .checkmark {
    width: 64px;
    height: 64px;
    background: #22c55e;
    color: #fff;
    border-radius: 50%;
    font-size: 2rem;
    font-weight: 700;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 1rem;
}

.thank-you h1 {
    margin-bottom: 0.5rem;
}

.thank-you p {
    color: #666;
}

/* Landing page */

.landing {
    max-width: 960px;
}

.landing-header {
    margin-bottom: 2rem;
}

.landing-header h1 {
    font-size: 2rem;
    margin-bottom: 0.25rem;
}

.landing-header p {
    color: #666;
    font-size: 1rem;
}

.channel-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 1.5rem;
}

.channel-card {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-decoration: none;
    color: inherit;
    padding: 1.5rem;
    transition: box-shadow 0.2s, transform 0.2s;
}

.channel-card:hover {
    box-shadow: 0 4px 12px rgba(0,0,0,0.15);
    transform: translateY(-2px);
}

.channel-card img {
    border-radius: 8px;
    margin-bottom: 1rem;
}

.channel-info {
    text-align: center;
    width: 100%;
}

.channel-info h2 {
    font-size: 1.1rem;
    font-weight: 600;
    margin-bottom: 0.25rem;
}

.channel-info .speakers {
    margin-bottom: 0;
    font-size: 0.9rem;
}

.empty-state {
    text-align: center;
    padding: 3rem 2rem;
    color: #666;
}