:root {
  --bg: #f6f7f9;
  --bg-elevated: #ffffff;
  --ink: #101218;
  --ink-soft: #5b6170;
  --ink-faint: #8b919e;
  --line: #e5e7ee;
  --line-strong: #cfd3de;
  --accent: #0d7370;
  --accent-deep: #0a5c5a;
  --accent-soft: #e7f5f4;
  --accent-glow: rgba(13, 115, 112, 0.18);
  --danger: #b42318;
  --danger-soft: #fef3f2;
  --success-soft: #ecf8f6;
  --shadow: 0 1px 2px rgba(16, 18, 24, 0.04), 0 18px 48px rgba(16, 18, 24, 0.07);
  --shadow-tight: 0 1px 2px rgba(16, 18, 24, 0.05), 0 8px 24px rgba(16, 18, 24, 0.06);
  --radius: 20px;
  --font-display: "Sora", sans-serif;
  --font-body: "Instrument Sans", sans-serif;
  --ease: cubic-bezier(0.22, 1, 0.36, 1);
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: var(--font-body);
  color: var(--ink);
  background: var(--bg);
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
  display: flex;
  flex-direction: column;
  position: relative;
  overflow-x: hidden;
}

/* —— Atmosphere —— */
.atmosphere {
  position: fixed;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  overflow: hidden;
  background: linear-gradient(180deg, #fbfbfc 0%, var(--bg) 42%, #f1f3f6 100%);
}

.orb {
  position: absolute;
  border-radius: 50%;
  filter: blur(60px);
  opacity: 0.7;
  animation: drift 18s var(--ease) infinite alternate;
}

.orb-a {
  width: 42vw;
  height: 42vw;
  max-width: 520px;
  max-height: 520px;
  left: -8%;
  top: -12%;
  background: radial-gradient(circle, rgba(13, 115, 112, 0.22), transparent 68%);
}

.orb-b {
  width: 36vw;
  height: 36vw;
  max-width: 440px;
  max-height: 440px;
  right: -6%;
  top: 8%;
  background: radial-gradient(circle, rgba(16, 18, 24, 0.08), transparent 70%);
  animation-delay: -6s;
}

.grid-fade {
  position: absolute;
  inset: 0;
  opacity: 0.4;
  background-image:
    linear-gradient(rgba(16, 18, 24, 0.035) 1px, transparent 1px),
    linear-gradient(90deg, rgba(16, 18, 24, 0.035) 1px, transparent 1px);
  background-size: 48px 48px;
  mask-image: radial-gradient(ellipse 70% 55% at 50% 20%, #000 20%, transparent 75%);
}

.atmosphere::after {
  content: "";
  position: absolute;
  inset: 0;
  opacity: 0.28;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 200 200' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='2' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)' opacity='0.5'/%3E%3C/svg%3E");
  mix-blend-mode: multiply;
}

/* —— Header —— */
.top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1.25rem clamp(1.25rem, 4vw, 3rem) 0.5rem;
  max-width: 980px;
  width: 100%;
  margin: 0 auto;
  animation: rise 0.65s var(--ease) both;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.75rem;
  text-decoration: none;
  color: var(--ink);
}

.brand-mark {
  width: 2.15rem;
  height: 2.15rem;
  border-radius: 9px;
  background: linear-gradient(145deg, #12908c 0%, var(--accent-deep) 100%);
  box-shadow:
    inset 0 0 0 1px rgba(255, 255, 255, 0.2),
    0 6px 16px rgba(13, 115, 112, 0.28);
  display: grid;
  place-items: center;
  flex-shrink: 0;
}

.brand-mark-inner {
  width: 0.95rem;
  height: 1.15rem;
  border: 1.5px solid rgba(255, 255, 255, 0.9);
  border-radius: 2px 2px 3px 3px;
  border-bottom-width: 3px;
  position: relative;
}

.brand-mark-inner::after {
  content: "";
  position: absolute;
  left: 2px;
  right: 2px;
  top: 3px;
  height: 1.5px;
  background: rgba(255, 255, 255, 0.75);
  box-shadow: 0 3px 0 rgba(255, 255, 255, 0.55);
}

.brand-text {
  display: flex;
  flex-direction: column;
  gap: 0.05rem;
}

.brand-name {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.12rem;
  letter-spacing: -0.035em;
  line-height: 1.1;
}

.brand-tag {
  font-size: 0.72rem;
  color: var(--ink-faint);
  letter-spacing: 0.01em;
}

/* —— Hero —— */
.hero {
  flex: 1;
  display: flex;
  flex-direction: column;
  justify-content: center;
  width: 100%;
  max-width: 620px;
  margin: 0 auto;
  padding: 1.75rem clamp(1.25rem, 4vw, 2rem) 2.5rem;
  transition: max-width 0.45s var(--ease);
}

.hero.has-preview {
  max-width: 900px;
  justify-content: flex-start;
}

.hero.has-preview .intro {
  margin-bottom: 1.1rem;
}

.hero.has-preview .headline {
  font-size: clamp(1.55rem, 3.5vw, 1.85rem);
}

.hero.has-preview .lede,
.hero.has-preview .eyebrow {
  display: none;
}

.intro {
  margin-bottom: 1.75rem;
}

.eyebrow {
  margin: 0 0 0.7rem;
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--accent);
  animation: rise 0.7s var(--ease) 0.04s both;
}

.headline {
  margin: 0 0 0.85rem;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: clamp(2.4rem, 6.2vw, 3.4rem);
  line-height: 1.05;
  letter-spacing: -0.045em;
  transition: font-size 0.4s var(--ease);
}

.headline-line {
  display: block;
  animation: rise 0.75s var(--ease) both;
}

.headline-line:nth-child(1) {
  animation-delay: 0.06s;
}

.headline-line:nth-child(2) {
  animation-delay: 0.12s;
}

.accent-line {
  color: var(--accent-deep);
  background: linear-gradient(105deg, var(--accent-deep) 20%, #1a8f8a 90%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.lede {
  margin: 0;
  color: var(--ink-soft);
  font-size: 1.05rem;
  max-width: 34rem;
  animation: rise 0.75s var(--ease) 0.16s both;
}

.lede code {
  font-family: ui-monospace, "SF Mono", Menlo, Consolas, monospace;
  font-size: 0.88em;
  background: rgba(16, 18, 24, 0.05);
  padding: 0.12em 0.38em;
  border-radius: 5px;
  color: var(--ink);
}

/* —— Uploader —— */
.uploader {
  background: var(--bg-elevated);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 0.7rem;
  animation: rise 0.8s var(--ease) 0.2s both;
  position: relative;
}

.drop-surface {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  min-height: 228px;
  padding: 1.75rem 1.25rem;
  border: 1.5px dashed var(--line-strong);
  border-radius: calc(var(--radius) - 7px);
  cursor: pointer;
  overflow: hidden;
  outline: none;
  transition:
    border-color 0.3s var(--ease),
    background 0.3s var(--ease),
    min-height 0.35s var(--ease),
    transform 0.35s var(--ease);
}

.drop-glow {
  position: absolute;
  inset: -40%;
  background: radial-gradient(circle at center, var(--accent-glow), transparent 55%);
  opacity: 0;
  transition: opacity 0.35s var(--ease);
  pointer-events: none;
}

.drop-surface:hover,
.drop-surface:focus-visible {
  border-color: var(--accent);
  background: #f7fbfb;
}

.drop-surface:hover .drop-glow,
.drop-surface:focus-visible .drop-glow {
  opacity: 1;
}

.drop-surface:focus-visible {
  box-shadow: 0 0 0 3px var(--accent-glow);
}

.uploader.is-dragover .drop-surface {
  border-color: var(--accent);
  border-style: solid;
  background: var(--accent-soft);
  transform: scale(1.01);
}

.uploader.is-dragover .drop-glow {
  opacity: 1;
}

.uploader.is-dragover .icon-ring {
  transform: translateY(-4px) scale(1.05);
  animation: bob 1s var(--ease) infinite alternate;
}

.uploader.has-file .drop-surface {
  min-height: 112px;
  border-style: solid;
  border-color: var(--line);
  background: #fafbfc;
  cursor: default;
}

.uploader.is-loading .drop-surface {
  cursor: wait;
  border-style: solid;
  border-color: var(--line);
  background: #fafbfc;
  min-height: 120px;
}

.drop-idle {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.4rem;
  text-align: center;
  position: relative;
  z-index: 1;
}

.uploader.has-file .drop-idle,
.uploader.is-loading .drop-idle {
  display: none;
}

.icon-ring {
  width: 3.4rem;
  height: 3.4rem;
  border-radius: 999px;
  display: grid;
  place-items: center;
  color: var(--accent);
  background: var(--accent-soft);
  margin-bottom: 0.45rem;
  transition: transform 0.4s var(--ease);
  box-shadow: inset 0 0 0 1px rgba(13, 115, 112, 0.08);
}

.drop-surface:hover .icon-ring {
  transform: translateY(-3px);
}

.drop-title {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 1.08rem;
  letter-spacing: -0.02em;
}

.drop-hint {
  margin: 0;
  font-size: 0.875rem;
  color: var(--ink-soft);
}

.drop-hint span {
  font-family: ui-monospace, "SF Mono", Menlo, Consolas, monospace;
  font-size: 0.9em;
}

/* File chip */
.file-chip {
  display: flex;
  align-items: center;
  gap: 0.85rem;
  width: 100%;
  max-width: 420px;
  padding: 0.15rem 0.25rem;
  position: relative;
  z-index: 1;
  animation: rise 0.35s var(--ease) both;
}

.file-icon {
  width: 2.75rem;
  height: 2.75rem;
  border-radius: 12px;
  display: grid;
  place-items: center;
  color: var(--accent-deep);
  background: var(--accent-soft);
  flex-shrink: 0;
}

.file-meta {
  min-width: 0;
  flex: 1;
}

.file-name {
  margin: 0;
  font-weight: 600;
  font-size: 0.95rem;
  letter-spacing: -0.01em;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.file-size {
  margin: 0.1rem 0 0;
  font-size: 0.8rem;
  color: var(--ink-soft);
}

.file-badge {
  flex-shrink: 0;
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--accent-deep);
  background: var(--accent-soft);
  border-radius: 999px;
  padding: 0.3rem 0.65rem;
}

.uploader.is-loading .file-chip {
  display: none;
}

/* Converting */
.converting-panel {
  width: 100%;
  max-width: 360px;
  text-align: center;
  position: relative;
  z-index: 1;
  animation: rise 0.3s var(--ease) both;
}

.progress-track {
  height: 4px;
  border-radius: 999px;
  background: rgba(16, 18, 24, 0.08);
  overflow: hidden;
  margin-bottom: 0.85rem;
}

.progress-bar {
  height: 100%;
  width: 28%;
  border-radius: inherit;
  background: linear-gradient(90deg, var(--accent), #1aa39d);
  animation: progress 1.6s var(--ease) infinite;
}

.converting-label {
  margin: 0;
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--ink-soft);
}

/* Actions */
.actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.55rem;
  padding: 0.9rem 0.45rem 0.25rem;
  animation: rise 0.35s var(--ease) both;
}

.btn {
  appearance: none;
  border: none;
  cursor: pointer;
  font-family: var(--font-body);
  font-weight: 600;
  font-size: 0.9375rem;
  border-radius: 999px;
  padding: 0.72rem 1.2rem;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.45rem;
  text-decoration: none;
  transition:
    background 0.2s var(--ease),
    color 0.2s var(--ease),
    transform 0.2s var(--ease),
    box-shadow 0.2s var(--ease),
    opacity 0.2s var(--ease);
}

.btn:active {
  transform: scale(0.98);
}

.btn:disabled {
  cursor: not-allowed;
  opacity: 0.55;
}

.btn-primary {
  background: var(--ink);
  color: #fff;
  min-width: 10.5rem;
  box-shadow: 0 8px 20px rgba(16, 18, 24, 0.18);
}

.btn-primary:hover:not(:disabled) {
  background: #242833;
  box-shadow: 0 10px 24px rgba(16, 18, 24, 0.22);
}

.btn-primary .btn-arrow {
  transition: transform 0.25s var(--ease);
}

.btn-primary:hover:not(:disabled) .btn-arrow {
  transform: translateX(3px);
}

.btn-ghost {
  background: transparent;
  color: var(--ink-soft);
}

.btn-ghost:hover:not(:disabled) {
  color: var(--ink);
  background: rgba(16, 18, 24, 0.045);
}

.uploader.is-loading .actions {
  opacity: 0.45;
  pointer-events: none;
}

/* Status toast */
.status {
  margin: 0.55rem 0.35rem 0.2rem;
  padding: 0.65rem 0.85rem;
  border-radius: 12px;
  font-size: 0.875rem;
  font-weight: 500;
  animation: rise 0.3s var(--ease) both;
}

.status.is-error {
  color: var(--danger);
  background: var(--danger-soft);
}

.status.is-success {
  color: var(--accent-deep);
  background: var(--success-soft);
}

.status.is-info {
  color: var(--ink-soft);
  background: #f3f4f7;
}

/* —— Preview —— */
.preview {
  margin-top: 1.35rem;
  background: var(--bg-elevated);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  overflow: hidden;
  animation: rise 0.55s var(--ease) both;
}

.preview-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  flex-wrap: wrap;
  padding: 0.95rem 1.15rem;
  border-bottom: 1px solid var(--line);
  background: linear-gradient(180deg, #fcfcfd, #f7f8fa);
}

.preview-meta {
  display: flex;
  align-items: center;
  gap: 0.85rem;
  min-width: 0;
}

.preview-pill {
  flex-shrink: 0;
  font-size: 0.7rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--accent-deep);
  background: var(--accent-soft);
  border-radius: 999px;
  padding: 0.35rem 0.65rem;
}

.preview-title {
  margin: 0;
  font-family: var(--font-display);
  font-size: 0.95rem;
  font-weight: 600;
  letter-spacing: -0.02em;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  max-width: min(42vw, 320px);
}

.preview-sub {
  margin: 0.1rem 0 0;
  font-size: 0.78rem;
  color: var(--ink-faint);
}

.preview-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.45rem;
}

.preview-stage {
  position: relative;
  background:
    radial-gradient(ellipse at top, rgba(13, 115, 112, 0.05), transparent 50%),
    #eaecf1;
  padding: 1rem;
  min-height: 440px;
}

.preview-skeleton {
  position: absolute;
  inset: 1rem;
  z-index: 1;
  background: #fff;
  border-radius: 10px;
  border: 1px solid var(--line);
  padding: 2rem 1.75rem;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  pointer-events: none;
  transition: opacity 0.35s var(--ease);
}

.preview.is-ready .preview-skeleton {
  opacity: 0;
  visibility: hidden;
}

.skel-line,
.skel-block {
  border-radius: 6px;
  background: linear-gradient(90deg, #eef0f4 25%, #f7f8fa 50%, #eef0f4 75%);
  background-size: 200% 100%;
  animation: shimmer 1.4s linear infinite;
}

.skel-line {
  height: 12px;
}

.skel-line.w60 { width: 60%; }
.skel-line.w75 { width: 75%; }
.skel-line.w85 { width: 85%; }
.skel-line.w90 { width: 90%; }
.skel-line.w50 { width: 50%; }

.skel-block {
  height: 120px;
  width: 100%;
  margin: 0.5rem 0;
}

.preview-frame {
  display: block;
  width: 100%;
  height: min(70vh, 780px);
  min-height: 420px;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: #fff;
  box-shadow: var(--shadow-tight);
  opacity: 0;
  transition: opacity 0.4s var(--ease);
}

.preview.is-ready .preview-frame {
  opacity: 1;
}

/* —— Footer —— */
.foot {
  padding: 0.75rem clamp(1.25rem, 4vw, 3rem) 1.75rem;
  text-align: center;
  animation: rise 0.7s var(--ease) 0.28s both;
}

.foot p {
  margin: 0;
  font-size: 0.8rem;
  color: var(--ink-faint);
}

/* —— Motion —— */
@keyframes rise {
  from {
    opacity: 0;
    transform: translateY(14px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes drift {
  from { transform: translate(0, 0) scale(1); }
  to { transform: translate(3%, 4%) scale(1.06); }
}

@keyframes bob {
  from { transform: translateY(-2px); }
  to { transform: translateY(-8px); }
}

@keyframes progress {
  0% { transform: translateX(-120%); width: 35%; }
  50% { width: 45%; }
  100% { transform: translateX(320%); width: 35%; }
}

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

@media (max-width: 600px) {
  .top {
    padding-top: 1rem;
  }

  .drop-surface {
    min-height: 200px;
  }

  .actions {
    flex-direction: column;
  }

  .btn-primary,
  .btn-ghost,
  .preview-actions .btn {
    width: 100%;
  }

  .preview-bar {
    flex-direction: column;
    align-items: stretch;
  }

  .preview-title {
    max-width: 70vw;
  }

  .preview-frame {
    min-height: 340px;
    height: 58vh;
  }

  .preview-stage {
    min-height: 360px;
    padding: 0.65rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation: none !important;
    transition: none !important;
  }

  .preview-frame,
  .preview.is-ready .preview-frame {
    opacity: 1;
  }
}