:root {
    --md-primary: #6750A4;
    --md-on-primary: #FFFFFF;
    --md-primary-container: #EADDFF;
    --md-on-primary-container: #21005D;
    --md-secondary: #625B71;
    --md-secondary-container: #E8DEF8;
    --md-surface: #FFFBFE;
    --md-surface-variant: #E7E0EC;
    --md-on-surface: #1C1B1F;
    --md-on-surface-variant: #49454F;
    --md-outline: #79747E;
    --md-outline-variant: #CAC4D0;
    --md-error: #B3261E;
    --md-shadow: rgba(0, 0, 0, 0.15);

    --app-bar-height: 64px;
    --search-bar-height: 56px;
}

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

body {
    font-family: 'Roboto', sans-serif;
    background-color: var(--md-surface);
    color: var(--md-on-surface);
    line-height: 1.5;
}

.hidden {
    display: none !important;
}

/* Screens */
.screen {
    min-height: 100vh;
}

/* Sign In Screen */
.sign-in-container {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    min-height: 100vh;
    padding: 24px;
    text-align: center;
}

.app-logo {
    width: 120px;
    height: 120px;
    margin-bottom: 24px;
}

.sign-in-container h1 {
    font-size: 32px;
    font-weight: 500;
    margin-bottom: 8px;
    color: var(--md-on-surface);
}

.sign-in-container p {
    color: var(--md-on-surface-variant);
    margin-bottom: 32px;
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 12px;
    padding: 12px 24px;
    border: none;
    border-radius: 100px;
    font-family: inherit;
    font-size: 14px;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s ease;
}

.btn-primary {
    background: var(--md-surface);
    color: var(--md-on-surface);
    box-shadow: 0 1px 3px var(--md-shadow), 0 1px 2px var(--md-shadow);
}

.btn-primary:hover {
    box-shadow: 0 4px 8px var(--md-shadow), 0 2px 4px var(--md-shadow);
}

.google-icon {
    flex-shrink: 0;
}

.icon-btn {
    width: 48px;
    height: 48px;
    border: none;
    background: transparent;
    border-radius: 50%;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    color: inherit;
    transition: background-color 0.2s;
}

.icon-btn:hover {
    background: var(--md-surface-variant);
}

/* App Bar */
.app-bar {
    height: var(--app-bar-height);
    padding: 0 8px 0 16px;
    display: flex;
    align-items: center;
    gap: 8px;
    background: var(--md-surface);
    position: sticky;
    top: 0;
    z-index: 100;
}

.app-bar h1 {
    flex: 1;
    font-size: 22px;
    font-weight: 500;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.app-bar-actions {
    display: flex;
    align-items: center;
}

/* Search Bar */
.search-container {
    margin: 0 16px 8px;
    padding: 0 16px;
    height: var(--search-bar-height);
    background: var(--md-surface-variant);
    border-radius: 28px;
    display: flex;
    align-items: center;
    gap: 12px;
}

.search-container .material-icons {
    color: var(--md-on-surface-variant);
}

.search-container input {
    flex: 1;
    border: none;
    background: transparent;
    font-size: 16px;
    font-family: inherit;
    color: var(--md-on-surface);
    outline: none;
}

.search-container input::placeholder {
    color: var(--md-on-surface-variant);
}

/* Filter Chips */
.filter-chips {
    display: flex;
    gap: 8px;
    padding: 8px 16px;
    overflow-x: auto;
    scrollbar-width: none;
}

.filter-chips::-webkit-scrollbar {
    display: none;
}

.chip {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 6px 16px;
    background: var(--md-surface);
    border: 1px solid var(--md-outline);
    border-radius: 8px;
    font-size: 14px;
    color: var(--md-on-surface-variant);
    cursor: pointer;
    white-space: nowrap;
    transition: all 0.2s;
}

.chip:hover {
    background: var(--md-surface-variant);
}

.chip.active {
    background: var(--md-secondary-container);
    border-color: transparent;
    color: var(--md-on-surface);
}

.chip .material-icons {
    font-size: 18px;
}

/* Loading State */
.loading {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 64px 24px;
    color: var(--md-on-surface-variant);
}

.spinner {
    width: 48px;
    height: 48px;
    border: 4px solid var(--md-surface-variant);
    border-top-color: var(--md-primary);
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin-bottom: 16px;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

/* Empty State */
.empty-state {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 64px 24px;
    color: var(--md-on-surface-variant);
    text-align: center;
}

.empty-state .material-icons {
    font-size: 64px;
    margin-bottom: 16px;
    opacity: 0.5;
}

/* Recipe Grid */
.recipe-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: 12px;
    padding: 12px;
}

/* Recipe Card */
.recipe-card {
    background: var(--md-surface);
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 1px 3px var(--md-shadow);
    cursor: pointer;
    transition: box-shadow 0.2s, transform 0.2s;
}

.recipe-card:hover {
    box-shadow: 0 4px 12px var(--md-shadow);
    transform: translateY(-2px);
}

.recipe-card-image {
    width: 100%;
    height: 120px;
    object-fit: cover;
    background: var(--md-surface-variant);
}

.recipe-card-image.placeholder {
    display: flex;
    align-items: center;
    justify-content: center;
}

.recipe-card-image.placeholder .material-icons {
    font-size: 48px;
    color: var(--md-outline);
}

.recipe-card-content {
    padding: 16px;
}

.recipe-card-title {
    font-size: 16px;
    font-weight: 500;
    margin-bottom: 4px;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.recipe-card-meta {
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: 12px;
    color: var(--md-on-surface-variant);
    margin-bottom: 8px;
}

.recipe-card-meta span {
    display: flex;
    align-items: center;
    gap: 4px;
}

.recipe-card-meta .material-icons {
    font-size: 16px;
}

.recipe-card-category {
    display: inline-block;
    padding: 4px 8px;
    background: var(--md-primary-container);
    color: var(--md-on-primary-container);
    border-radius: 4px;
    font-size: 12px;
}

.recipe-card-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 4px;
    margin-top: 8px;
}

.recipe-card-tag {
    font-size: 11px;
    color: var(--md-on-surface-variant);
    background: var(--md-surface-variant);
    padding: 2px 8px;
    border-radius: 4px;
}

.recipe-card-favorite {
    color: var(--md-error);
}

/* Detail Screen */
#detail-screen .app-bar {
    background: transparent;
    position: absolute;
    width: 100%;
}

#detail-screen .app-bar h1 {
    color: white;
    text-shadow: 0 1px 3px rgba(0,0,0,0.5);
}

#detail-screen .app-bar .icon-btn {
    color: white;
}

#detail-screen .app-bar .icon-btn:hover {
    background: rgba(255,255,255,0.2);
}

.detail-content {
    padding-bottom: 32px;
}

.detail-hero {
    width: 100%;
    height: 280px;
    object-fit: cover;
    background: var(--md-surface-variant);
}

.detail-hero.placeholder {
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--md-primary-container);
}

.detail-hero.placeholder .material-icons {
    font-size: 80px;
    color: var(--md-on-primary-container);
    opacity: 0.5;
}

.detail-body {
    padding: 24px 16px;
    max-width: 800px;
    margin: 0 auto;
}

.detail-header {
    margin-bottom: 24px;
}

.detail-header h2 {
    font-size: 24px;
    font-weight: 500;
    margin-bottom: 8px;
}

.detail-header-meta {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 16px;
    color: var(--md-on-surface-variant);
    font-size: 14px;
}

.detail-header-meta span {
    display: flex;
    align-items: center;
    gap: 4px;
}

.detail-header-meta .material-icons {
    font-size: 20px;
}

.detail-category {
    display: inline-block;
    padding: 6px 12px;
    background: var(--md-primary-container);
    color: var(--md-on-primary-container);
    border-radius: 8px;
    font-size: 14px;
    margin-top: 12px;
}

.detail-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    margin-top: 12px;
}

.detail-tag {
    padding: 4px 12px;
    background: var(--md-surface-variant);
    color: var(--md-on-surface-variant);
    border-radius: 16px;
    font-size: 13px;
}

.detail-description {
    color: var(--md-on-surface-variant);
    margin-bottom: 24px;
    font-size: 15px;
}

.detail-section {
    margin-bottom: 24px;
}

.detail-section h3 {
    font-size: 18px;
    font-weight: 500;
    margin-bottom: 12px;
    display: flex;
    align-items: center;
    gap: 8px;
}

.detail-section h3 .material-icons {
    color: var(--md-primary);
}

.detail-section-content {
    background: var(--md-surface-variant);
    border-radius: 12px;
    padding: 16px;
    white-space: pre-wrap;
    font-size: 15px;
    line-height: 1.7;
}

.detail-source {
    margin-top: 24px;
}

.detail-source a {
    color: var(--md-primary);
    text-decoration: none;
    display: flex;
    align-items: center;
    gap: 8px;
}

.detail-source a:hover {
    text-decoration: underline;
}

/* Responsive */
@media (max-width: 600px) {
    .recipe-grid {
        grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
    }

    .detail-hero {
        height: 220px;
    }

    .detail-body {
        padding: 16px;
    }
}

/* Dark mode support */
@media (prefers-color-scheme: dark) {
    :root {
        --md-primary: #D0BCFF;
        --md-on-primary: #381E72;
        --md-primary-container: #4F378B;
        --md-on-primary-container: #EADDFF;
        --md-secondary: #CCC2DC;
        --md-secondary-container: #4A4458;
        --md-surface: #1C1B1F;
        --md-surface-variant: #49454F;
        --md-on-surface: #E6E1E5;
        --md-on-surface-variant: #CAC4D0;
        --md-outline: #938F99;
        --md-outline-variant: #49454F;
        --md-error: #F2B8B5;
        --md-shadow: rgba(0, 0, 0, 0.3);
    }

    #detail-screen .app-bar h1 {
        text-shadow: none;
    }
}