:root {
    --tg-theme-bg-color: var(--tg-theme-bg-color, #ffffff);
    --tg-theme-text-color: var(--tg-theme-text-color, #000000);
    --tg-theme-hint-color: var(--tg-theme-hint-color, #999999);
    --tg-theme-link-color: var(--tg-theme-link-color, #2481cc);
    --tg-theme-button-color: var(--tg-theme-button-color, #2481cc);
    --tg-theme-button-text-color: var(--tg-theme-button-text-color, #ffffff);
    --tg-theme-secondary-bg-color: var(--tg-theme-secondary-bg-color, #f3f3f3);

    --brand-color: #3a506b; /* Глубокий сине-серый, как гранит */
    --brand-color-accent: #5bc0de; /* Яркий акцент */
}

* { box-sizing: border-box; }

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
    margin: 0;
    padding: 20px 15px;
    background-color: var(--tg-theme-bg-color);
    color: var(--tg-theme-text-color);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

.screen { width: 100%; }
#loader { text-align: center; padding-top: 50px; }
.spinner {
    border: 4px solid rgba(0, 0, 0, 0.1);
    width: 36px; height: 36px;
    border-radius: 50%;
    border-left-color: var(--brand-color);
    animation: spin 1s ease infinite;
    margin: 0 auto 10px;
}
@keyframes spin { 0% { transform: rotate(0deg); } 100% { transform: rotate(360deg); } }

header, #feedback-section, footer {
    text-align: center;
    margin-bottom: 25px;
}
header h1 {
    font-size: 24px;
    font-weight: 600;
    margin: 0 0 5px 0;
}
header p, #feedback-section p {
    color: var(--tg-theme-hint-color);
    margin: 0;
}
hr {
    border: none;
    border-top: 1px solid var(--tg-theme-secondary-bg-color);
    margin: 30px 0;
}

#product-catalog {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 20px;
}
.product-item {
    background-color: var(--tg-theme-secondary-bg-color);
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 4px 12px rgba(0,0,0,0.05);
    transition: transform 0.2s ease-in-out;
}
.product-item:hover {
    transform: translateY(-5px);
}
.product-item img {
    width: 100%;
    height: 180px;
    object-fit: cover;
    display: block;
}
.product-item .product-info {
    padding: 15px;
}
.product-info h3 {
    margin: 0 0 8px 0;
    font-size: 18px;
    font-weight: 600;
}
.product-info p {
    margin: 0 0 12px 0;
    font-size: 14px;
    color: var(--tg-theme-hint-color);
    line-height: 1.4;
}
.product-info strong {
    font-size: 16px;
    color: var(--brand-color);
}

#feedback-form {
    display: flex;
    flex-direction: column;
    gap: 12px;
    margin-top: 20px;
    max-width: 400px;
    margin-left: auto;
    margin-right: auto;
}
#feedback-form input, #feedback-form textarea {
    width: 100%;
    padding: 12px 15px;
    border-radius: 8px;
    border: 1px solid var(--tg-theme-hint-color);
    background-color: var(--tg-theme-bg-color);
    color: var(--tg-theme-text-color);
    font-size: 16px;
    font-family: inherit;
}
#feedback-form textarea {
    min-height: 120px;
    resize: vertical;
}
#feedback-form input:focus, #feedback-form textarea:focus {
    outline: none;
    border-color: var(--brand-color);
    box-shadow: 0 0 0 2px rgba(58, 80, 107, 0.3);
}

#main-action-button {
    width: 100%;
    padding: 14px;
    border: none;
    border-radius: 8px;
    background-color: var(--tg-theme-button-color, var(--brand-color));
    color: var(--tg-theme-button-text-color, #ffffff);
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: background-color 0.2s;
}
#main-action-button:disabled {
    background-color: var(--tg-theme-hint-color);
    cursor: not-allowed;
}

footer {
    font-size: 14px;
    color: var(--tg-theme-hint-color);
    margin-top: 40px;
}

/* Стиль для кнопки администрирования */
.admin-link {
    display: inline-block;
    margin-bottom: 15px;
    padding: 8px 15px;
    background-color: var(--tg-theme-secondary-bg-color);
    color: var(--tg-theme-link-color);
    border: 1px solid var(--tg-theme-hint-color);
    border-radius: 8px;
    text-decoration: none;
    font-weight: 500;
    transition: background-color 0.2s;
}
.admin-link:hover {
    background-color: var(--tg-theme-bg-color);
}