/* ===========================================================
   通用组件：按钮、卡片、Chip、加载动画
   =========================================================== */

/* ---------- Button ---------- */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    height: 2.5rem;
    padding: 0 1.5rem;
    border-radius: 6.25rem;
    border: 1px solid transparent;
    font-size: var(--md-sys-typescale-label-large-size);
    font-weight: 500;
    cursor: pointer;
    transition: background-color var(--transition-duration) var(--transition-timing), box-shadow var(--transition-duration) var(--transition-timing), transform var(--transition-duration) var(--transition-timing);
    user-select: none;
    -webkit-tap-highlight-color: transparent;
}
.btn:hover {
    box-shadow: 0 1px 3px 1px rgba(0,0,0,0.15);
}
.btn:active {
    transform: scale(0.98);
}
.btn--filled {
    background-color: var(--md-sys-color-primary);
    color: var(--md-sys-color-on-primary);
}
.btn--filled:hover { background-color: color-mix(in srgb, var(--md-sys-color-primary), white 8%); }
.btn--tonal {
    background-color: var(--md-sys-color-secondary-container);
    color: var(--md-sys-color-on-secondary-container);
}
.btn--tonal:hover { background-color: color-mix(in srgb, var(--md-sys-color-secondary-container), white 8%); }
.btn--text {
    height: auto;
    padding: 0.5rem 0.75rem;
    color: var(--md-sys-color-on-surface-variant);
    background-color: transparent;
}
.btn--text:hover { background-color: color-mix(in srgb, var(--md-sys-color-on-surface), transparent 88%); box-shadow: none; }
.btn--icon {
    width: 2.5rem;
    height: 2.5rem;
    padding: 0;
    font-size: 1.5rem;
    color: var(--md-sys-color-on-surface-variant);
    background-color: transparent;
}
.btn--icon:hover { background-color: color-mix(in srgb, var(--md-sys-color-on-surface), transparent 88%); box-shadow: none; }

.btn--tonal .material-symbols-outlined,
.btn--filled .material-symbols-outlined {
    flex-shrink: 0;
}

/* ---------- Card ---------- */
.card {
    border-radius: 1.5rem;
    padding: 1.5rem;
    transition: background-color var(--transition-duration) var(--transition-timing), border-color var(--transition-duration) var(--transition-timing), transform var(--transition-duration) var(--transition-timing);
}
.card--filled {
    background-color: var(--md-sys-color-surface-container-high);
}
.card--outlined {
    background-color: transparent;
    border: 1px solid var(--md-sys-color-outline);
}
.card--outlined:hover {
    background-color: var(--md-sys-color-surface-container);
    transform: translateY(-4px);
}
.card--error {
    background-color: var(--md-sys-color-error-container);
    color: var(--md-sys-color-on-error-container);
}
.card-title-icon {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    margin-bottom: 1rem;
}
.card-subtitle {
    color: var(--md-sys-color-on-surface-variant);
}

/* ---------- Chip ---------- */
.chips-group {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 0.75rem;
}
.chip {
    display: inline-flex;
    align-items: center;
    gap: 0.375rem;
    height: 2rem;
    padding: 0 0.75rem;
    border-radius: 2rem;
    font-size: var(--md-sys-typescale-label-large-size);
    background-color: var(--md-sys-color-secondary-container);
    color: var(--md-sys-color-on-secondary-container);
}
.chip--small {
    height: 1.5rem;
    padding: 0.125rem 0.5rem;
    font-size: 0.75rem;
    background-color: var(--md-sys-color-primary-container);
    color: var(--md-sys-color-on-primary-container);
}

/* ---------- Loader ---------- */
.loader {
    width: 48px;
    height: 48px;
    border-radius: 50%;
    display: inline-block;
    border: 4px solid var(--md-sys-color-surface-variant);
    border-top: 4px solid var(--md-sys-color-primary);
    animation: spin 1s linear infinite;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

/* ---------- Contributors List ---------- */
.contributors-list {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 0.75rem;
}

@media (min-width: 640px) {
    .contributors-list {
        grid-template-columns: repeat(3, 1fr);
    }
}

@media (min-width: 768px) {
    .contributors-list {
        grid-template-columns: repeat(4, 1fr);
    }
}

@media (min-width: 1024px) {
    .contributors-list {
        grid-template-columns: repeat(5, 1fr);
    }
}

.contributor-card {
    background-color: var(--md-sys-color-surface-container);
    border-radius: 0.75rem;
    transition: background-color var(--transition-duration) var(--transition-timing), transform var(--transition-duration) var(--transition-timing);
}

.contributor-card:hover {
    background-color: var(--md-sys-color-surface-container-high);
    transform: translateY(-2px);
}

.contributor-card a {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 0.75rem;
    text-decoration: none;
    color: inherit;
}

.contributor-card img {
    width: 48px;
    height: 48px;
    border-radius: 50%;
    flex-shrink: 0;
}

.contributor-info {
    display: flex;
    flex-direction: column;
    gap: 0.25rem;
    min-width: 0;
}

.contributor-name {
    font-size: var(--md-sys-typescale-label-large-size);
    font-weight: 500;
    color: var(--md-sys-color-on-surface);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.contributor-roles {
    display: flex;
    flex-wrap: wrap;
    gap: 0.25rem;
    color: var(--md-sys-color-on-surface-variant);
    font-size: 0.75rem;
}

.contributor-roles i {
    opacity: 0.7;
    transition: opacity var(--transition-duration) var(--transition-timing);
}

.contributor-card:hover .contributor-roles i {
    opacity: 1;
}