@layer base, components, utilities;

/* ============================================================
   Layer: base — CSS reset, theme variables, typography
   ============================================================ */

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

  :root {
    --color-accent: #0088cc;
    --color-accent-hover: #006da3;
    --color-accent-light: rgba(0, 136, 204, 0.08);
    --color-accent-ring: rgba(0, 136, 204, 0.4);
    --color-success: #34c759;
    --color-error: #ff3b30;
    --color-warning: #ff9500;

    --color-bg: #ffffff;
    --color-bg-secondary: #f5f5f7;
    --color-bg-tertiary: #e8e8ed;
    --color-text: #1d1d1f;
    --color-text-secondary: #86868b;
    --color-text-tertiary: #aeaeb2;
    --color-border: #d2d2d7;
    --color-border-light: #e5e5ea;

    --color-glass-bg: rgba(255, 255, 255, 0.72);
    --color-glass-border: rgba(0, 0, 0, 0.08);

    --radius-sm: 6px;
    --radius-md: 10px;
    --radius-lg: 16px;
    --radius-full: 9999px;

    --font-sans: -apple-system, BlinkMacSystemFont, "SF Pro Display", "SF Pro Text", "Helvetica Neue", "Segoe UI", system-ui, sans-serif;
    --font-mono: "SF Mono", "Cascadia Code", "Fira Code", "JetBrains Mono", ui-monospace, monospace;

    --shadow-glass: 0 8px 32px rgba(0, 0, 0, 0.06);

    --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
    --ease-in-out: cubic-bezier(0.65, 0, 0.35, 1);

    --transition-fast: 150ms ease;
    --transition-normal: 250ms var(--ease-out);
    --transition-slow: 400ms var(--ease-out);
  }

  [data-theme="dark"] {
    --color-accent: #2aabee;
    --color-accent-hover: #1e9ad9;
    --color-accent-light: rgba(42, 171, 238, 0.12);
    --color-accent-ring: rgba(42, 171, 238, 0.5);

    --color-bg: #1c1c1e;
    --color-bg-secondary: #2c2c2e;
    --color-bg-tertiary: #3a3a3c;
    --color-text: #f5f5f7;
    --color-text-secondary: #98989d;
    --color-text-tertiary: #636366;
    --color-border: #3a3a3c;
    --color-border-light: #2c2c2e;

    --color-glass-bg: rgba(44, 44, 46, 0.72);
    --color-glass-border: rgba(255, 255, 255, 0.08);

    --shadow-glass: 0 8px 32px rgba(0, 0, 0, 0.2);
  }

  html {
    font-family: var(--font-sans);
    font-size: 16px;
    line-height: 1.5;
    color: var(--color-text);
    background-color: var(--color-bg);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
  }

  body {
    min-height: 100dvh;
    display: flex;
    flex-direction: column;
    background-color: var(--color-bg);
    transition: background-color var(--transition-normal), color var(--transition-normal);
  }

  ::selection {
    background-color: var(--color-accent);
    color: #fff;
  }

  :focus-visible {
    outline: 2px solid var(--color-accent);
    outline-offset: 2px;
    border-radius: var(--radius-sm);
  }

  button:focus-visible,
  input:focus-visible,
  select:focus-visible {
    outline: 2px solid var(--color-accent);
    outline-offset: 2px;
  }

  img, video {
    max-width: 100%;
    display: block;
  }

  a {
    color: var(--color-accent);
    text-decoration: none;
  }

  a:hover {
    text-decoration: underline;
  }

  hr {
    border: none;
    border-top: 1px solid var(--color-border-light);
    margin: 0;
  }

  [hidden] {
    display: none !important;
  }
}

/* ============================================================
   Layer: components — reusable UI components
   ============================================================ */

@layer components {
  /* ---- Header ---- */
  .app-header {
    position: sticky;
    top: 0;
    z-index: 100;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 8px 16px;
    background: var(--color-glass-bg);
    backdrop-filter: blur(20px) saturate(180%);
    -webkit-backdrop-filter: blur(20px) saturate(180%);
    border-bottom: 1px solid var(--color-glass-border);
  }

  .header-brand {
    display: flex;
    align-items: center;
    gap: 8px;
  }

  .brand-icon {
    color: var(--color-accent);
    flex-shrink: 0;
  }

  .brand-name {
    font-size: 1rem;
    font-weight: 600;
    color: var(--color-text);
    letter-spacing: -0.01em;
  }

  .header-nav {
    display: flex;
    align-items: center;
    gap: 4px;
  }

  /* ---- Buttons ---- */
  .btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
    padding: 8px 16px;
    font-family: var(--font-sans);
    font-size: 0.875rem;
    font-weight: 500;
    line-height: 1.25;
    color: var(--color-text);
    background: var(--color-bg-secondary);
    border: none;
    border-radius: var(--radius-md);
    cursor: pointer;
    user-select: none;
    white-space: nowrap;
    transition: background var(--transition-fast), color var(--transition-fast), transform var(--transition-fast), opacity var(--transition-fast);
  }

  .btn:hover {
    background: var(--color-bg-tertiary);
  }

  .btn:active {
    transform: scale(0.97);
  }

  .btn:disabled {
    opacity: 0.4;
    cursor: not-allowed;
    transform: none;
  }

  .btn-primary {
    color: #fff;
    background: var(--color-accent);
  }

  .btn-primary:hover {
    background: var(--color-accent-hover);
  }

  .btn-ghost {
    background: transparent;
  }

  .btn-ghost:hover {
    background: var(--color-accent-light);
    color: var(--color-accent);
  }

  .btn-sm {
    padding: 4px 10px;
    font-size: 0.8125rem;
    border-radius: var(--radius-sm);
  }

  .btn-lg {
    padding: 12px 28px;
    font-size: 1rem;
    border-radius: var(--radius-lg);
  }

  .btn-icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 36px;
    height: 36px;
    padding: 0;
    font-family: var(--font-sans);
    color: var(--color-text-secondary);
    background: transparent;
    border: none;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: color var(--transition-fast), background var(--transition-fast);
  }

  .btn-icon:hover {
    color: var(--color-text);
    background: var(--color-bg-secondary);
  }

  .btn-icon:active {
    transform: scale(0.94);
  }

  /* ---- Form inputs ---- */
  .input {
    width: 100%;
    padding: 8px 12px;
    font-family: var(--font-sans);
    font-size: 0.875rem;
    color: var(--color-text);
    background: var(--color-bg);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
    appearance: none;
  }

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

  .input:focus {
    outline: none;
    border-color: var(--color-accent);
    box-shadow: 0 0 0 3px var(--color-accent-ring);
  }

  .input-mono {
    font-family: var(--font-mono);
    font-size: 0.8125rem;
  }

  /* ---- Select ---- */
  .select-lang {
    padding: 4px 8px;
    font-family: var(--font-sans);
    font-size: 0.8125rem;
    font-weight: 500;
    color: var(--color-text-secondary);
    background: transparent;
    border: none;
    border-radius: var(--radius-sm);
    cursor: pointer;
    appearance: none;
    transition: color var(--transition-fast), background var(--transition-fast);
  }

  .select-lang:hover {
    color: var(--color-text);
    background: var(--color-bg-secondary);
  }

  .select-lang:focus:not(:focus-visible) {
    outline: none;
  }

  /* ---- Form layout ---- */
  .form-group {
    display: flex;
    flex-direction: column;
    gap: 4px;
  }

  .form-group label {
    font-size: 0.8125rem;
    font-weight: 600;
    color: var(--color-text);
    letter-spacing: -0.01em;
  }

  .form-hint {
    font-size: 0.75rem;
    color: var(--color-text-secondary);
    line-height: 1.4;
  }

  .form-divider {
    margin: 4px 0;
  }

  .form-actions {
    display: flex;
    justify-content: flex-end;
    gap: 8px;
    margin-top: 8px;
  }

  /* ---- Template help ---- */
  .template-help {
    display: flex;
    flex-wrap: wrap;
    gap: 2px 16px;
    font-size: 0.75rem;
    color: var(--color-text-secondary);
    line-height: 1.6;
  }

  .template-help code {
    font-family: var(--font-mono);
    font-size: 0.6875rem;
    padding: 1px 4px;
    background: var(--color-bg-tertiary);
    border-radius: 3px;
    color: var(--color-accent);
  }

  /* ---- Hero ---- */
  .hero {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 48px 24px;
    text-align: center;
  }

  .hero-content {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 16px;
    max-width: 420px;
  }

  .hero-icon {
    color: var(--color-accent);
    opacity: 0.8;
  }

  .hero-title {
    font-size: 1.75rem;
    font-weight: 700;
    letter-spacing: -0.02em;
    color: var(--color-text);
  }

  .hero-desc {
    font-size: 0.9375rem;
    color: var(--color-text-secondary);
    line-height: 1.6;
  }

  /* ---- Upload zone ---- */
  .upload-section {
    padding: 24px;
    max-width: 640px;
    margin: 0 auto;
    width: 100%;
  }

  .upload-zone {
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 200px;
    padding: 40px 24px;
    border: 2px dashed var(--color-border);
    border-radius: var(--radius-lg);
    cursor: pointer;
    transition: border-color var(--transition-fast), background var(--transition-fast), transform var(--transition-fast);
  }

  .upload-zone:hover,
  .upload-zone:focus-visible {
    border-color: var(--color-accent);
    background: var(--color-accent-light);
  }

  .upload-zone.drag-over {
    border-color: var(--color-accent);
    background: var(--color-accent-light);
    transform: scale(1.01);
  }

  .upload-zone-content {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 8px;
    text-align: center;
    pointer-events: none;
  }

  .upload-icon {
    color: var(--color-text-tertiary);
    transition: color var(--transition-fast);
  }

  .upload-zone:hover .upload-icon,
  .upload-zone.drag-over .upload-icon {
    color: var(--color-accent);
  }

  .upload-text {
    font-size: 0.9375rem;
    font-weight: 500;
    color: var(--color-text);
  }

  .upload-limit {
    font-size: 0.75rem;
    color: var(--color-text-secondary);
  }

  /* ---- Upload progress ---- */
  .upload-progress {
    margin-top: 16px;
    display: flex;
    flex-direction: column;
    gap: 8px;
  }

  .progress-bar {
    width: 100%;
    height: 4px;
    background: var(--color-bg-tertiary);
    border-radius: var(--radius-full);
    overflow: hidden;
  }

  .progress-fill {
    height: 100%;
    width: 0%;
    background: var(--color-accent);
    border-radius: var(--radius-full);
    transition: width 200ms linear;
  }

  .progress-fill.indeterminate {
    width: 40%;
    animation: progressIndeterminate 1.2s var(--ease-in-out) infinite;
  }

  @keyframes progressIndeterminate {
    0%   { transform: translateX(-100%); }
    100% { transform: translateX(350%); }
  }

  .progress-text {
    font-size: 0.75rem;
    color: var(--color-text-secondary);
    text-align: center;
  }

  /* ---- Gallery ---- */
  .gallery-section {
    padding: 0 24px 48px;
    max-width: 1200px;
    margin: 0 auto;
    width: 100%;
  }

  .gallery-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 16px;
  }

  .gallery-title {
    font-size: 1.125rem;
    font-weight: 600;
    color: var(--color-text);
    letter-spacing: -0.01em;
  }

  .gallery-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
    gap: 12px;
  }

  .gallery-empty {
    grid-column: 1 / -1;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 12px;
    padding: 48px 24px;
    color: var(--color-text-tertiary);
    text-align: center;
  }

  .gallery-empty p {
    font-size: 0.875rem;
  }

  /* ---- Gallery card ---- */
  .gallery-card {
    position: relative;
    background: var(--color-bg-secondary);
    border-radius: var(--radius-md);
    overflow: hidden;
    cursor: pointer;
    transition: transform var(--transition-fast), box-shadow var(--transition-fast);
  }

  .gallery-card:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-glass);
  }

  .gallery-card-thumb {
    width: 100%;
    aspect-ratio: 16 / 10;
    object-fit: cover;
    background: var(--color-bg-tertiary);
  }

  .gallery-card-body {
    padding: 10px 12px;
    display: flex;
    flex-direction: column;
    gap: 2px;
  }

  .gallery-card-name {
    font-size: 0.8125rem;
    font-weight: 500;
    color: var(--color-text);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
  }

  .gallery-card-meta {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 8px;
  }

  .gallery-card-date {
    font-size: 0.75rem;
    color: var(--color-text-secondary);
  }

  .gallery-card-actions {
    display: flex;
    gap: 2px;
    opacity: 0;
    transition: opacity var(--transition-fast);
  }

  .gallery-card:hover .gallery-card-actions {
    opacity: 1;
  }

  .gallery-card-actions .btn-icon {
    width: 28px;
    height: 28px;
  }

  /* ---- Dialog ---- */
  .dialog {
    margin: auto;
    padding: 0;
    border: none;
    border-radius: var(--radius-lg);
    background: var(--color-glass-bg);
    backdrop-filter: blur(40px) saturate(180%);
    -webkit-backdrop-filter: blur(40px) saturate(180%);
    box-shadow: var(--shadow-glass);
    color: var(--color-text);
    max-width: 480px;
    width: calc(100vw - 32px);
    max-height: 85dvh;
    overflow: visible;
    transition: opacity var(--transition-normal), transform var(--transition-normal);
  }

  .dialog::backdrop {
    background: rgba(0, 0, 0, 0.3);
    backdrop-filter: blur(4px);
    -webkit-backdrop-filter: blur(4px);
    animation: fadeIn 200ms ease;
  }

  .dialog[open] {
    animation: dialogIn var(--transition-normal) forwards;
  }

  .dialog-panel {
    display: flex;
    flex-direction: column;
    max-height: 85dvh;
  }

  .dialog-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 16px 20px 12px;
    border-bottom: 1px solid var(--color-border-light);
  }

  .dialog-header h2 {
    font-size: 1.0625rem;
    font-weight: 600;
    letter-spacing: -0.01em;
  }

  .dialog-body {
    padding: 16px 20px 20px;
    display: flex;
    flex-direction: column;
    gap: 14px;
    overflow-y: auto;
  }

  .dialog-close {
    flex-shrink: 0;
  }

  /* ---- Preview dialog ---- */
  .dialog-preview {
    max-width: 90vw;
    max-height: 90dvh;
    width: auto;
  }

  .preview-panel {
    max-height: 90dvh;
  }

  .preview-header {
    flex-wrap: wrap;
    gap: 8px;
  }

  .preview-name {
    font-size: 0.875rem;
    font-weight: 500;
    word-break: break-all;
    min-width: 0;
  }

  .preview-header-actions {
    display: flex;
    align-items: center;
    gap: 8px;
    flex-shrink: 0;
  }

  .preview-body {
    padding: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    max-height: 70dvh;
    overflow: auto;
    background: var(--color-bg-tertiary);
    border-bottom-left-radius: var(--radius-lg);
    border-bottom-right-radius: var(--radius-lg);
  }

  .preview-body img,
  .preview-body video {
    max-width: 100%;
    max-height: 70dvh;
    object-fit: contain;
  }

  /* ---- Toast ---- */
  .toast-container {
    position: fixed;
    bottom: 20px;
    right: 20px;
    z-index: 1000;
    display: flex;
    flex-direction: column-reverse;
    gap: 8px;
    pointer-events: none;
  }

  .toast {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 10px 16px;
    font-size: 0.8125rem;
    font-weight: 500;
    color: #fff;
    background: #1d1d1f;
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-glass);
    pointer-events: auto;
    animation: toastIn 300ms var(--ease-out);
    transition: opacity 200ms ease, transform 200ms ease;
  }

  [data-theme="dark"] .toast {
    background: #f5f5f7;
    color: #1d1d1f;
  }

  .toast.toast-success {
    background: var(--color-success);
    color: #fff;
  }

  .toast.toast-error {
    background: var(--color-error);
    color: #fff;
  }

  .toast.removing {
    opacity: 0;
    transform: translateX(20px);
  }

  /* ---- Theme toggle icons ---- */
  [data-theme="light"] .icon-moon { display: none; }
  [data-theme="dark"] .icon-sun { display: none; }
}

/* ============================================================
   Layer: utilities — small helper classes
   ============================================================ */

@layer utilities {
  .sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border-width: 0;
  }

  .text-center { text-align: center; }
  .text-mono { font-family: var(--font-mono); }
}

/* ============================================================
   Animations
   ============================================================ */

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

@keyframes dialogIn {
  from {
    opacity: 0;
    transform: scale(0.96) translateY(8px);
  }
  to {
    opacity: 1;
    transform: scale(1) translateY(0);
  }
}

@keyframes toastIn {
  from {
    opacity: 0;
    transform: translateX(24px);
  }
  to {
    opacity: 1;
    transform: translateX(0);
  }
}

/* ============================================================
   View Transition API
   ============================================================ */

::view-transition-old(root),
::view-transition-new(root) {
  animation-duration: 300ms;
}

::view-transition-old(root) {
  animation: fadeOut 300ms var(--ease-in-out);
}

::view-transition-new(root) {
  animation: fadeIn 300ms var(--ease-in-out);
}

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

/* ============================================================
   Responsive
   ============================================================ */

@media (max-width: 640px) {
  .app-header {
    padding: 6px 12px;
  }

  .brand-name {
    font-size: 0.875rem;
  }

  .hero {
    padding: 32px 16px;
  }

  .hero-title {
    font-size: 1.375rem;
  }

  .hero-desc {
    font-size: 0.875rem;
  }

  .upload-section {
    padding: 16px;
  }

  .upload-zone {
    min-height: 160px;
    padding: 28px 16px;
  }

  .gallery-section {
    padding: 0 12px 32px;
  }

  .gallery-grid {
    grid-template-columns: repeat(auto-fill, minmax(160px, 1fr));
    gap: 8px;
  }

  .dialog {
    width: calc(100vw - 16px);
    max-height: 90dvh;
  }

  .dialog-preview {
    max-width: 100vw;
    max-height: 100dvh;
    border-radius: 0;
  }

  .preview-body {
    max-height: 60dvh;
  }

  .preview-body img,
  .preview-body video {
    max-height: 60dvh;
  }

  .template-help {
    gap: 1px 12px;
  }

  .toast-container {
    bottom: 12px;
    right: 12px;
    left: 12px;
  }

  .toast {
    font-size: 0.8125rem;
    padding: 8px 12px;
  }
}