:root {
    --color-bg: #fafaf9;
    --color-surface: #ffffff;
    --color-text: #171717;
    --color-text-secondary: #737373;
    --color-accent: #171717;
    --color-border: #e5e5e5;
    --color-error: #dc2626;
    --color-success: #16a34a;

    /* System Font Stacks - Sans Serif */
    --font-sans-apple: -apple-system, BlinkMacSystemFont, 'SF Pro Display', 'SF Pro Text', sans-serif;
    --font-sans-windows: 'Segoe UI', 'Segoe UI Variable', sans-serif;
    --font-sans-android: 'Roboto', sans-serif;
    --font-sans-linux: 'Ubuntu', 'Cantarell', 'Noto Sans', sans-serif;
    --font-sans-fallback: 'Helvetica Neue', 'Arial', sans-serif;

    /* System Font Stacks - Monospace */
    --font-mono-apple: ui-monospace, 'SF Mono', 'Menlo', 'Monaco', monospace;
    --font-mono-windows: 'Cascadia Code', 'Cascadia Mono', 'Consolas', monospace;
    --font-mono-android: 'Roboto Mono', monospace;
    --font-mono-linux: 'Ubuntu Mono', 'Liberation Mono', 'Noto Mono', monospace;
    --font-mono-fallback: 'Courier New', 'Courier', monospace;

    /* Unified Font Stacks (Cross-Platform) */
    --font-sans: -apple-system, BlinkMacSystemFont, 'Segoe UI Variable', 'Segoe UI', 'Roboto', 'Oxygen', 'Ubuntu', 'Cantarell', 'Fira Sans', 'Droid Sans', 'Helvetica Neue', 'Helvetica', 'Arial', sans-serif;
    --font-mono: ui-monospace, 'SF Mono', 'Cascadia Code', 'Cascadia Mono', 'Segoe UI Mono', 'Roboto Mono', 'Ubuntu Mono', 'Menlo', 'Monaco', 'Consolas', 'Liberation Mono', 'Courier New', monospace;

    /* Font Weights */
    --font-weight-normal: 400;
    --font-weight-medium: 500;
    --font-weight-semibold: 600;
    --font-weight-bold: 700;

    /* Font Features for Monospace */
    --font-mono-features: 'calt' 1, 'liga' 1, 'zero' 1, 'ss01' 1;

    --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
    --ease-in-out: cubic-bezier(0.87, 0, 0.13, 1);
}

@media (prefers-color-scheme: dark) {
    :root {
        --color-bg: #0a0a0a;
        --color-surface: #171717;
        --color-text: #fafaf9;
        --color-text-secondary: #a3a3a3;
        --color-accent: #fafaf9;
        --color-border: #2a2a2a;
        --color-error: #f87171;
        --color-success: #4ade80;
    }
}

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

/* 全局禁用文本选择 */
* {
    -webkit-user-select: none;
    -moz-user-select: none;
    user-select: none;
}

/* 允许输入框文本选择 */
input[type="text"],
textarea,
.input-field {
    -webkit-user-select: text;
    -moz-user-select: text;
    user-select: text;
}

/* 自定义文本选择颜色 - 浅色模式 */
::selection {
    background-color: rgba(23, 23, 23, 0.15);
    color: var(--color-text);
}

::-moz-selection {
    background-color: rgba(23, 23, 23, 0.15);
    color: var(--color-text);
}

/* 自定义文本选择颜色 - 深色模式 */
@media (prefers-color-scheme: dark) {
    ::selection {
        background-color: rgba(250, 250, 249, 0.2);
        color: var(--color-text);
    }

    ::-moz-selection {
        background-color: rgba(250, 250, 249, 0.2);
        color: var(--color-text);
    }
}

html {
    font-size: 16px;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    text-rendering: optimizeLegibility;
}

body {
    font-family: var(--font-sans);
    background: var(--color-bg);
    color: var(--color-text);
    line-height: 1.6;
    overflow-x: hidden;
    transition: background-color 0.3s var(--ease-out), color 0.3s var(--ease-out);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.main {
    flex: 1;
}

/* Font Feature Settings for Monospace */
.tagline,
.input-field,
.content-meta,
.photo-number,
.toast,
.footer {
    font-feature-settings: var(--font-mono-features);
    font-variant-numeric: slashed-zero tabular-nums;
}

/* Grain Texture */
.grain {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    pointer-events: none;
    opacity: 0.03;
    z-index: 9999;
    background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 400 400' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='noiseFilter'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='2.5' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23noiseFilter)'/%3E%3C/svg%3E");
}

@media (prefers-color-scheme: dark) {
    .grain {
        opacity: 0.015;
    }
}

/* Container */
.container {
    max-width: 640px;
    margin: 0 auto;
    padding: 0 1.5rem;
    transition: transform 0.6s var(--ease-out), opacity 0.6s var(--ease-out);
}

body::before {
    content: '';
    flex: 1;
    transition: flex 0.6s var(--ease-out);
}

/* 解析完成后，移除上方的弹性空间 */
body.content-loaded::before {
    flex: 0;
}

.header {
    flex-shrink: 0;
}

.main {
    flex-shrink: 0;
}

/* 移动端特定布局重置 */
@media (max-width: 640px) {
    .container {
        width: 100%;
        transition: transform 0.6s var(--ease-out);
    }

    .footer {
        margin-top: auto;
    }
}

/* Header */
.header {
    padding: 4rem 0 3rem;
    animation: fadeSlideDown 0.8s var(--ease-out);
}

.header-content {
    text-align: center;
}

.logo {
    font-size: 1.5rem;
    font-weight: 500;
    letter-spacing: -0.03em;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.75rem;
    margin-bottom: 0.75rem;
}

.logo-text {
    font-weight: 700;
}

.logo-icon {
    width: 32px;
    height: 32px;
    fill: currentColor;
}

.tagline {
    font-size: 0.8125rem;
    color: var(--color-text-secondary);
    font-family: var(--font-mono);
    letter-spacing: 0.05em;
    text-transform: uppercase;
    opacity: 0.8;
}

/* Input Section */
.input-section {
    margin-bottom: 3rem;
    animation: fadeSlideUp 0.8s var(--ease-out) 0.1s backwards;
}

.input-wrapper {
    position: relative;
    display: flex;
    gap: 0.5rem;
    margin-bottom: 0.75rem;
    align-items: stretch;
}

.input-field {
    flex: 1;
    padding: 1rem 1.25rem;
    font-size: 1rem;
    font-family: var(--font-mono);
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    color: var(--color-text);
    transition: border-color 0.3s var(--ease-out), box-shadow 0.3s var(--ease-out), background-color 0.3s var(--ease-out);
    outline: none;
    -webkit-appearance: none;
    border-radius: 0;
    position: relative;
    z-index: 1;
}

.input-field:focus {
    border-color: var(--color-accent);
    box-shadow: 0 0 0 1px var(--color-accent);
}

.input-field:hover:not(:focus) {
    border-color: var(--color-text-secondary);
}

.input-field::placeholder {
    color: var(--color-text-secondary);
}

.btn-fetch {
    padding: 1rem 2rem;
    font-size: 0.875rem;
    font-weight: 600;
    font-family: var(--font-sans);
    background: var(--color-accent);
    color: var(--color-bg);
    border: 1px solid var(--color-accent);
    cursor: pointer;
    transition: all 0.3s var(--ease-out);
    position: relative;
    overflow: hidden;
    letter-spacing: 0.02em;
    -webkit-appearance: none;
    border-radius: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    width: 120px;
}

.btn-fetch:hover:not(:disabled) {
    box-shadow: 0 4px 12px rgba(23, 23, 23, 0.15);
    transform: translateY(-1px);
}

@media (prefers-color-scheme: dark) {
    .btn-fetch:hover:not(:disabled) {
        box-shadow: 0 4px 12px rgba(250, 250, 249, 0.1);
    }
}

.btn-fetch:active:not(:disabled) {
    transform: translateY(0);
}

.btn-fetch:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

.btn-loader {
    display: none;
    width: 14px;
    height: 14px;
    border: 2px solid var(--color-bg);
    border-top-color: transparent;
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
}

.btn-fetch.loading .btn-text {
    display: none;
}

.btn-fetch.loading .btn-loader {
    display: block;
}

.input-field.error {
    border-color: var(--color-error);
    box-shadow: 0 0 0 1px var(--color-error);
    animation: shake 0.4s var(--ease-out);
}

.input-field.error:hover {
    border-color: var(--color-error);
}

@keyframes shake {
    0%, 100% { transform: translateX(0); }
    20% { transform: translateX(-4px); }
    40% { transform: translateX(4px); }
    60% { transform: translateX(-4px); }
    80% { transform: translateX(4px); }
}

/* Result Section */
.result-section {
    display: none;
    animation: fadeSlideUp 0.6s var(--ease-out);
}

.result-section.active {
    display: block;
}

/* Content Card */
.content-card {
    padding: 2rem 0;
    border-top: 1px solid var(--color-border);
    border-bottom: 1px solid var(--color-border);
    margin-bottom: 2rem;
    transition: border-color 0.3s var(--ease-out);
}

.content-header {
    margin-bottom: 1rem;
}

.content-meta {
    display: flex;
    gap: 1rem;
    font-size: 0.75rem;
    font-family: var(--font-mono);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.meta-type {
    color: var(--color-text);
    font-weight: 600;
}

.meta-author {
    color: var(--color-text-secondary);
}

.content-title {
    font-size: 1.5rem;
    font-weight: 500;
    letter-spacing: -0.02em;
    line-height: 1.3;
}

/* Action Grid */
.action-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1rem;
    margin-bottom: 3rem;
    display: none;
}

.action-grid.active {
    display: grid;
}

.action-card {
    aspect-ratio: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    cursor: pointer;
    transition: all 0.3s var(--ease-out);
    text-decoration: none;
    color: inherit;
    position: relative;
    overflow: hidden;
    -webkit-tap-highlight-color: transparent;
}

.action-card::before {
    content: '';
    position: absolute;
    inset: 0;
    background: var(--color-accent);
    transform: translateY(100%);
    transition: transform 0.4s var(--ease-out);
}

.action-card:hover::before,
.action-card:active::before {
    transform: translateY(0);
}

.action-card:hover {
    border-color: var(--color-accent);
}

.action-card:hover .action-icon,
.action-card:hover .action-label,
.action-card:active .action-icon,
.action-card:active .action-label {
    color: var(--color-bg);
}

.action-icon {
    font-size: 1.5rem;
    margin-bottom: 0.5rem;
    position: relative;
    z-index: 1;
    transition: color 0.3s var(--ease-out);
}

.action-label {
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    position: relative;
    z-index: 1;
    transition: color 0.3s var(--ease-out);
}

.action-card.copied .action-label {
    color: var(--color-success);
}

.action-card.copied .action-icon {
    animation: copySuccess 0.6s var(--ease-out);
}

@keyframes copySuccess {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.2); }
}

/* Photo Section */
.photo-section {
    display: none;
    margin-bottom: 3rem;
}

.photo-section.active {
    display: block;
}

.photo-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(180px, 1fr));
    gap: 1rem;
}

.photo-item {
    position: relative;
    aspect-ratio: 1;
    overflow: hidden;
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    cursor: pointer;
    transition: all 0.3s var(--ease-out);
    -webkit-tap-highlight-color: transparent;
}

/* 图片加载占位符 */
.photo-item::before {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(
        90deg,
        var(--color-surface) 0%,
        var(--color-border) 50%,
        var(--color-surface) 100%
    );
    background-size: 200% 100%;
    animation: shimmer 1.5s infinite;
    opacity: 1;
    transition: opacity 0.3s var(--ease-out);
}

.photo-item.loaded::before {
    opacity: 0;
}

@keyframes shimmer {
    0% { background-position: -200% 0; }
    100% { background-position: 200% 0; }
}

.photo-item:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.1);
}

@media (prefers-color-scheme: dark) {
    .photo-item:hover {
        box-shadow: 0 8px 24px rgba(255, 255, 255, 0.05);
    }
}

.photo-item img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
    transition: transform 0.3s var(--ease-out), opacity 0.3s var(--ease-out);
    opacity: 0;
}

.photo-item img.loaded {
    opacity: 1;
}

.photo-item:hover img {
    transform: scale(1.05);
}

/* 图片加载失败状态 */
.photo-item.error::after {
    content: 'Failed to load';
    position: absolute;
    inset: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--color-surface);
    color: var(--color-text-secondary);
    font-size: 0.75rem;
    font-family: var(--font-mono);
}

/* Info Section */
.info-section {
    padding: 3rem 0;
    border-top: 1px solid var(--color-border);
    animation: fadeSlideUp 0.8s var(--ease-out) 0.2s backwards;
    transition: border-color 0.3s var(--ease-out);
}

.info-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
}

.info-item {
    text-align: center;
}

.info-number {
    font-size: 0.75rem;
    font-family: var(--font-mono);
    color: var(--color-text-secondary);
    margin-bottom: 0.5rem;
    font-weight: 600;
}

.info-text {
    font-size: 0.875rem;
    color: var(--color-text);
}

/* Footer */
.footer {
    padding: 3rem 0;
    text-align: center;
    font-size: 0.75rem;
    color: var(--color-text-secondary);
    font-family: var(--font-mono);
    animation: fadeSlideUp 0.8s var(--ease-out) 0.3s backwards;
}

.footer p {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.75rem;
}

.footer p::before {
    content: '·';
    position: absolute;
    left: 50%;
    transform: translateX(-50%);
    opacity: 0.3;
}

.footer-link {
    color: var(--color-text);
    text-decoration: none;
    transition: color 0.3s var(--ease-out);
    position: relative;
}

.footer-link:hover {
    color: var(--color-accent);
}

.footer-link::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    right: 0;
    height: 1px;
    background: var(--color-accent);
    transform: scaleX(0);
    transition: transform 0.3s var(--ease-out);
}

.footer-link:hover::after {
    transform: scaleX(1);
}

.modal {
    position: fixed;
    inset: 0;
    z-index: 1000;
    display: none;
    align-items: center;
    justify-content: center;
    padding: 2rem;
}

.modal.active {
    display: flex;
}

.modal-backdrop {
    position: absolute;
    inset: 0;
    background: rgba(250, 250, 249, 0.95);
    backdrop-filter: blur(8px);
    animation: fadeIn 0.3s var(--ease-out);
}

@media (prefers-color-scheme: dark) {
    .modal-backdrop {
        background: rgba(10, 10, 10, 0.95);
    }
}

.modal-container {
    position: relative;
    width: fit-content;
    height: fit-content;
    max-width: calc(100vw - 4rem);
    max-height: calc(100vh - 4rem);
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    animation: modalSlideUp 0.4s var(--ease-out);
    display: flex;
    align-items: center;
    justify-content: center;
}

.modal-close {
    position: absolute;
    top: -1.25rem;
    right: -1.25rem;
    width: 2.5rem;
    height: 2.5rem;
    background: var(--color-accent);
    color: var(--color-bg);
    border: none;
    cursor: pointer;
    font-size: 1.5rem;
    line-height: 1;
    transition: all 0.3s var(--ease-out);
    z-index: 10;
    display: flex;
    align-items: center;
    justify-content: center;
    -webkit-appearance: none;
    border-radius: 50%;
}

.modal-close:hover {
    background: var(--color-text-secondary);
}

.modal-close:active {
    transform: scale(0.95);
}

.modal-content {
    position: relative;
    max-width: 100%;
    max-height: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 3.5rem 3rem;
}

.modal-content video,
.modal-content img {
    max-width: calc(100vw - 10rem);
    max-height: calc(100vh - 10rem);
    width: auto;
    height: auto;
    object-fit: contain;
    display: block;
}

/* Toast */
.toast {
    position: fixed;
    bottom: 2.5rem;
    left: 50%;
    transform: translateX(-50%) translateY(20px);
    padding: 0.75rem 1.25rem;
    background: rgba(23, 23, 23, 0.9);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    color: white;
    font-size: 0.8125rem;
    font-family: var(--font-mono);
    border: 1px solid rgba(255, 255, 255, 0.1);
    z-index: 2000;
    opacity: 0;
    visibility: hidden;
    transition: all 0.4s var(--ease-out);
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.2);
    display: flex;
    align-items: center;
    gap: 0.625rem;
    pointer-events: none;
    border-radius: 0;
    white-space: nowrap;
}

.toast::before {
    content: '✅';
    font-size: 0.875rem;
    display: flex;
    align-items: center;
    justify-content: center;
}

@media (prefers-color-scheme: dark) {
    .toast {
        background: rgba(250, 250, 249, 0.9);
        color: #0a0a0a;
        border-color: rgba(0, 0, 0, 0.1);
    }
}

.toast.active {
    transform: translateX(-50%) translateY(0);
    opacity: 1;
    visibility: visible;
}

.toast.error {
    background: rgba(220, 38, 38, 0.9);
    border-color: rgba(220, 38, 38, 0.2);
    color: white;
}

.toast.error::before {
    content: '⚠️';
}

/* Animations */
@keyframes fadeSlideDown {
    from {
        opacity: 0;
        transform: translateY(-20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes fadeSlideUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

@keyframes modalSlideUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

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

@keyframes shake {
    0%, 100% { transform: translateX(0); }
    25% { transform: translateX(-4px); }
    75% { transform: translateX(4px); }
}

/* Responsive */
@media (max-width: 640px) {
    .header {
        padding: 3rem 0 2rem;
    }

    .logo {
        font-size: 1.25rem;
    }

    .logo-icon {
        width: 28px;
        height: 28px;
    }

    .tagline {
        font-size: 0.75rem;
        letter-spacing: 0.08em;
    }

    .input-wrapper {
        flex-direction: column;
    }

    .btn-fetch {
        width: 100%;
    }

    .content-title {
        font-size: 1.25rem;
    }

    .action-grid {
        gap: 0.75rem;
    }

    .info-grid {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }

    .photo-grid {
        grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
        gap: 0.75rem;
    }

    /* 移动端模态框优化 */
    .modal {
        padding: 1rem;
    }

    .modal-container {
        max-width: calc(100vw - 2rem);
        max-height: calc(100vh - 2rem);
    }

    .modal-content {
        padding: 3rem 0.5rem;
    }

    .modal-content video,
    .modal-content img {
        max-width: calc(100vw - 5rem);
        max-height: calc(100vh - 8rem);
    }

    .modal-close {
        top: auto;
        right: auto;
        bottom: -1.25rem;
        left: 50%;
        transform: translateX(-50%);
        width: 2.5rem;
        height: 2.5rem;
        font-size: 1.5rem;
    }

    .modal-close:active {
        transform: translateX(-50%) scale(0.95);
    }

    /* 移动端优化间距 */
    .container {
        padding: 0 1rem;
    }

    .input-section {
        margin-bottom: 2rem;
    }

    .content-card {
        padding: 1.5rem 0;
        margin-bottom: 1.5rem;
    }

    .footer {
        padding: 2rem 0;
    }
}

@media (max-width: 480px) {
    .action-grid {
        grid-template-columns: 1fr;
    }

    .action-card {
        aspect-ratio: auto;
        padding: 1.5rem;
    }

    .photo-grid {
        grid-template-columns: repeat(auto-fill, minmax(120px, 1fr));
    }
}


/* Smooth scrolling */
html {
    scroll-behavior: smooth;
}

/* Focus visible for accessibility */
*:focus-visible {
    outline: 2px solid var(--color-accent);
    outline-offset: 2px;
}

/* Remove outline for input field focus */
.input-field:focus-visible {
    outline: none;
}

/* Font Utility Classes */
.font-sans {
    font-family: var(--font-sans) !important;
}

.font-mono {
    font-family: var(--font-mono) !important;
}

/* Platform-Specific Font Classes */
.font-apple {
    font-family: var(--font-sans-apple) !important;
}

.font-windows {
    font-family: var(--font-sans-windows) !important;
}

.font-android {
    font-family: var(--font-sans-android) !important;
}

.font-linux {
    font-family: var(--font-sans-linux) !important;
}

/* Monospace Platform-Specific */
.font-mono-apple {
    font-family: var(--font-mono-apple) !important;
}

.font-mono-windows {
    font-family: var(--font-mono-windows) !important;
}

.font-mono-android {
    font-family: var(--font-mono-android) !important;
}

.font-mono-linux {
    font-family: var(--font-mono-linux) !important;
}

/* Font Weight Utilities */
.font-normal {
    font-weight: var(--font-weight-normal);
}

.font-medium {
    font-weight: var(--font-weight-medium);
}

.font-semibold {
    font-weight: var(--font-weight-semibold);
}

.font-bold {
    font-weight: var(--font-weight-bold);
}

/* Additional Monospace Features */
.mono-features {
    font-feature-settings: var(--font-mono-features);
    font-variant-numeric: slashed-zero tabular-nums;
}

/* Tabular Numbers for Better Alignment */
.tabular-nums {
    font-variant-numeric: tabular-nums;
}

/* Platform-Specific Font Rendering Optimizations */
@supports (-webkit-appearance: none) {
    /* macOS/iOS specific rendering */
    body {
        -webkit-font-smoothing: antialiased;
        -moz-osx-font-smoothing: grayscale;
    }
}

@supports (-ms-ime-align: auto) {
    /* Windows specific rendering */
    body {
        font-smoothing: antialiased;
        text-rendering: optimizeLegibility;
    }
}