:root {
  color-scheme: light;
  --bg: #f4f7f5;
  --surface: #ffffff;
  --surface-soft: #eef4f1;
  --clay: #f7faf6;
  --clay-shadow: rgba(81, 108, 96, 0.20);
  --clay-highlight: rgba(255, 255, 255, 0.92);
  --liquid: #dcefe8;
  --liquid-deep: #c8e3d8;
  --ink: #17201c;
  --muted: #64746c;
  --line: #d8e3dd;
  --primary: #146b5c;
  --primary-strong: #0d5146;
  --accent: #b88a2c;
  --danger: #a23131;
  --shadow: 0 24px 70px rgba(21, 45, 36, 0.14);
}

* {
  box-sizing: border-box;
}

[hidden] {
  display: none !important;
}

body {
  margin: 0;
  min-height: 100dvh;
  background:
    radial-gradient(120% 80% at 14% 12%, rgba(208, 229, 221, 0.72), transparent 42%),
    radial-gradient(90% 70% at 88% 82%, rgba(226, 207, 166, 0.42), transparent 38%),
    var(--bg);
  color: var(--ink);
  font-family: Inter, "Microsoft YaHei", "PingFang SC", system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  letter-spacing: 0;
}

button,
select,
input {
  font: inherit;
}

.app-shell {
  width: min(1120px, calc(100% - 32px));
  min-height: 100dvh;
  margin: 0 auto;
  display: grid;
  place-items: center;
  padding: 32px 0;
}

.converter-panel {
  position: relative;
  overflow: hidden;
  width: 100%;
  display: grid;
  grid-template-columns: minmax(260px, 0.82fr) minmax(320px, 1.18fr);
  gap: 28px;
  align-items: stretch;
  background:
    linear-gradient(145deg, rgba(255, 255, 255, 0.92), rgba(246, 250, 247, 0.86)),
    var(--clay);
  border: 1px solid rgba(216, 227, 221, 0.9);
  border-radius: 8px;
  box-shadow:
    16px 18px 42px var(--clay-shadow),
    -12px -12px 28px var(--clay-highlight),
    inset 0 1px 0 rgba(255, 255, 255, 0.82);
  padding: 28px;
}

.converter-panel > *:not(.liquid-ribbon):not(.deckle-edge) {
  position: relative;
  z-index: 2;
}

.liquid-ribbon {
  position: absolute;
  z-index: 1;
  pointer-events: none;
  background:
    linear-gradient(135deg, rgba(255, 255, 255, 0.72), transparent 38%),
    linear-gradient(145deg, var(--liquid), var(--liquid-deep));
  filter: drop-shadow(0 14px 18px rgba(33, 86, 72, 0.12));
  opacity: 0.86;
}

.liquid-ribbon-top {
  width: 360px;
  height: 138px;
  top: -50px;
  right: 20%;
  clip-path: path("M5,72 C42,8 111,14 155,39 C196,62 218,5 283,17 C346,29 369,89 338,120 C301,156 239,129 196,130 C142,132 95,162 45,132 C5,109 -10,93 5,72 Z");
}

.liquid-ribbon-bottom {
  width: 310px;
  height: 126px;
  right: -72px;
  bottom: -38px;
  background:
    linear-gradient(135deg, rgba(255, 255, 255, 0.62), transparent 42%),
    linear-gradient(145deg, #f1ddaa, #d4efdf);
  clip-path: path("M8,55 C29,7 94,0 135,26 C174,51 210,15 253,30 C301,47 322,97 286,120 C246,147 211,105 166,113 C111,124 76,144 31,111 C7,93 -4,75 8,55 Z");
}

.deckle-edge {
  position: absolute;
  z-index: 1;
  pointer-events: none;
  opacity: 0.58;
  background:
    radial-gradient(circle at 50% 7px, rgba(20, 107, 92, 0.16) 0 2px, transparent 3px) 0 0 / 12px 15px repeat-y,
    linear-gradient(180deg, rgba(20, 107, 92, 0.04), rgba(184, 138, 44, 0.04));
  filter: blur(0.2px);
}

.deckle-edge-left {
  width: 18px;
  inset: 22px auto 22px 0;
}

.deckle-edge-right {
  width: 18px;
  inset: 22px 0 22px auto;
  transform: scaleX(-1);
}

.panel-copy {
  display: flex;
  flex-direction: column;
  justify-content: center;
  min-height: 460px;
  padding: 8px;
}

.eyebrow {
  margin: 0 0 16px;
  color: var(--primary);
  font-size: 13px;
  font-weight: 700;
  text-transform: uppercase;
}

h1 {
  margin: 0;
  max-width: 100%;
  font-size: clamp(40px, 5.8vw, 64px);
  line-height: 0.98;
  letter-spacing: 0;
}

.intro {
  max-width: 420px;
  margin: 24px 0 0;
  color: var(--muted);
  font-size: 17px;
  line-height: 1.75;
}

.converter-form {
  display: flex;
  flex-direction: column;
  gap: 18px;
  background:
    linear-gradient(145deg, rgba(255, 255, 255, 0.96), rgba(239, 247, 243, 0.92));
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 18px;
  box-shadow:
    10px 12px 24px rgba(81, 108, 96, 0.13),
    -8px -8px 20px rgba(255, 255, 255, 0.95),
    inset 0 1px 0 rgba(255, 255, 255, 0.9);
}

.drop-zone {
  position: relative;
  overflow: hidden;
  min-height: 270px;
  border: 1px solid rgba(147, 171, 159, 0.58);
  border-radius: 8px;
  background:
    radial-gradient(circle at 84% 78%, rgba(202, 230, 219, 0.62), transparent 24%),
    linear-gradient(145deg, rgba(255, 255, 255, 0.86), rgba(231, 244, 238, 0.86)),
    var(--surface-soft);
  display: grid;
  place-items: center;
  align-content: center;
  gap: 12px;
  padding: 28px;
  text-align: center;
  cursor: pointer;
  box-shadow:
    0 10px 28px rgba(49, 89, 75, 0.08),
    inset 8px 8px 20px rgba(73, 103, 91, 0.08),
    inset -10px -10px 24px rgba(255, 255, 255, 0.86);
  transition: border-color 180ms ease, box-shadow 180ms ease, filter 180ms ease, transform 180ms ease;
}

.drop-zone::before {
  content: "";
  position: absolute;
  inset: 14px;
  z-index: -1;
  border: 1px dashed rgba(99, 133, 118, 0.52);
  border-radius: 8px;
  box-shadow:
    0 0 0 0 rgba(20, 107, 92, 0),
    inset 0 0 0 1px rgba(255, 255, 255, 0.42);
  transition: border-color 180ms ease, box-shadow 180ms ease;
}

.drop-zone::after {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -1;
  background:
    linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.72), transparent);
  opacity: 0;
  transform: translateX(-72%);
  transition: opacity 180ms ease, transform 560ms ease;
}

.drop-zone:hover,
.drop-zone.is-dragging {
  border-color: rgba(20, 107, 92, 0.68);
  filter: saturate(1.04);
  transform: translateY(-1px);
  box-shadow:
    0 0 0 4px rgba(20, 107, 92, 0.10),
    0 0 30px rgba(20, 107, 92, 0.28),
    0 18px 38px rgba(49, 89, 75, 0.12),
    inset 0 0 34px rgba(20, 107, 92, 0.10),
    inset -10px -10px 24px rgba(255, 255, 255, 0.88);
}

.drop-zone:hover::before,
.drop-zone.is-dragging::before {
  border-color: rgba(20, 107, 92, 0.68);
  box-shadow:
    0 0 18px rgba(20, 107, 92, 0.24),
    inset 0 0 18px rgba(20, 107, 92, 0.08);
}

.drop-zone:hover::after,
.drop-zone.is-dragging::after {
  opacity: 0.9;
  transform: translateX(72%);
}

.drop-zone:focus-within {
  outline: 3px solid rgba(20, 107, 92, 0.22);
  outline-offset: 3px;
}

.drop-zone input {
  position: absolute;
  inline-size: 1px;
  block-size: 1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
}

.upload-icon,
.download-button {
  display: inline-grid;
  place-items: center;
}

.upload-icon {
  width: 64px;
  height: 64px;
  border-radius: 8px;
  color: var(--primary);
  background: linear-gradient(145deg, #ffffff, #e8f1ed);
  border: 1px solid var(--line);
  box-shadow:
    6px 7px 14px rgba(74, 100, 88, 0.16),
    -5px -5px 12px rgba(255, 255, 255, 0.92),
    inset 0 1px 0 rgba(255, 255, 255, 0.9);
}

svg {
  width: 26px;
  height: 26px;
  fill: none;
  stroke: currentColor;
  stroke-width: 2;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.drop-title {
  font-size: 22px;
  font-weight: 750;
}

.drop-hint {
  max-width: 430px;
  color: var(--muted);
  font-size: 15px;
  line-height: 1.6;
}

.file-info,
.download-area,
.controls {
  display: grid;
  gap: 14px;
}

.file-info {
  grid-template-columns: 1fr 140px;
  padding: 14px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fbfcfb;
}

.pdf-tools {
  display: grid;
  gap: 14px;
  padding: 14px;
  border: 1px solid rgba(20, 107, 92, 0.16);
  border-radius: 8px;
  background: linear-gradient(145deg, rgba(255, 255, 255, 0.78), rgba(230, 243, 237, 0.74));
}

.pdf-toolbar {
  display: grid;
  grid-template-columns: minmax(150px, 1fr) 128px;
  gap: 12px;
  align-items: end;
}

.page-field {
  display: grid;
  gap: 7px;
  color: var(--muted);
  font-size: 13px;
  font-weight: 700;
}

.page-field select {
  min-height: 44px;
  border: 1px solid #b7c8bf;
  border-radius: 8px;
  background: linear-gradient(145deg, #ffffff, #f2f7f4);
  color: var(--ink);
  padding: 0 12px;
}

.secondary-button {
  min-height: 44px;
  border: 1px solid rgba(20, 107, 92, 0.35);
  border-radius: 999px;
  color: var(--primary-strong);
  background: linear-gradient(145deg, #ffffff, #edf7f2);
  cursor: pointer;
  font-weight: 800;
  box-shadow:
    5px 6px 13px rgba(81, 108, 96, 0.12),
    inset 0 1px 0 rgba(255, 255, 255, 0.9);
  transition: transform 180ms ease, box-shadow 180ms ease, border-color 180ms ease;
}

.secondary-button:hover {
  transform: translateY(-1px);
  border-color: rgba(20, 107, 92, 0.66);
  box-shadow:
    0 0 0 4px rgba(20, 107, 92, 0.08),
    0 10px 22px rgba(20, 107, 92, 0.16);
}

.pdf-preview {
  max-height: 360px;
  overflow: auto;
  border: 1px solid rgba(147, 171, 159, 0.48);
  border-radius: 8px;
  background: #f8fbf9;
  padding: 12px;
}

.pdf-preview canvas {
  display: block;
  width: 100%;
  height: auto;
  background: #fff;
  border-radius: 6px;
  box-shadow: 0 10px 26px rgba(33, 64, 52, 0.12);
}

.label {
  display: block;
  margin-bottom: 4px;
  color: var(--muted);
  font-size: 12px;
  font-weight: 700;
}

strong {
  display: block;
  overflow-wrap: anywhere;
}

.controls {
  grid-template-columns: 1fr 136px;
  align-items: end;
}

.format-field {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  color: var(--muted);
  font-size: 13px;
  font-weight: 700;
  margin: 0;
  padding: 0;
  border: 0;
}

.format-field legend {
  flex-basis: 100%;
  margin: 0 0 -2px;
  padding: 0;
  color: var(--muted);
}

.format-picker {
  --_clr-primary: #6a7b72;
  --_clr-hover: var(--primary);
  --_clr-checked: var(--primary-strong);
}

.format-picker > div {
  --_clr-current: var(--_clr-primary);
  position: relative;
  display: flex;
  align-items: center;
  gap: 7px;
  min-height: 48px;
  padding: 6px 8px;
  border: 1px solid color-mix(in srgb, var(--_clr-current) 38%, white);
  border-radius: 8px;
  background: linear-gradient(145deg, #ffffff, #eef6f1);
  box-shadow:
    5px 6px 12px rgba(81, 108, 96, 0.12),
    -4px -4px 10px rgba(255, 255, 255, 0.9),
    inset 0 1px 0 rgba(255, 255, 255, 0.9);
  transition: border-color 150ms ease-in-out, transform 150ms ease-in-out, box-shadow 150ms ease-in-out;
}

.format-picker input[type="radio"] {
  appearance: none;
  outline: none;
  width: 22px;
  height: 22px;
  aspect-ratio: 1;
  margin: 0;
  padding: 3px;
  border: 1px solid var(--_clr-current);
  border-radius: 6px;
  background: transparent;
  display: grid;
  place-content: center;
  cursor: pointer;
}

.format-picker input[type="radio"]::after {
  content: "\2714";
  opacity: 0;
  color: var(--_clr-checked);
  font-size: 14px;
  line-height: 1;
  transition: opacity 150ms ease-in-out;
}

.format-picker label {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  cursor: pointer;
  color: var(--_clr-current);
  transition: color 150ms ease-in-out;
}

.format-picker > div:hover,
.format-picker label:hover,
.format-picker input[type="radio"]:focus-visible + label,
.format-picker input[type="radio"]:hover + label {
  --_clr-current: var(--_clr-hover);
  transform: translateY(-1px);
}

.format-picker input[type="radio"]:focus-visible {
  outline: 3px solid rgba(20, 107, 92, 0.28);
  outline-offset: 3px;
}

.format-picker input[type="radio"]:hover::after,
.format-picker input[type="radio"]:focus-visible::after {
  opacity: 0.45;
  color: var(--_clr-hover);
}

.format-picker > div:has(input[type="radio"]:checked) {
  --_clr-current: var(--_clr-checked);
  border-color: rgba(13, 81, 70, 0.5);
  background:
    linear-gradient(145deg, rgba(255, 255, 255, 0.96), rgba(214, 239, 228, 0.96));
  box-shadow:
    inset 5px 5px 12px rgba(20, 107, 92, 0.10),
    inset -5px -5px 12px rgba(255, 255, 255, 0.86);
}

.format-picker input[type="radio"]:checked + label {
  color: var(--_clr-checked);
}

.format-picker input[type="radio"]:checked::after {
  opacity: 1;
}

.primary-button {
  position: relative;
  isolation: isolate;
  overflow: hidden;
  min-height: 56px;
  border: 0;
  border-radius: 999px;
  color: #fff;
  background: linear-gradient(180deg, #38a58e 0%, #167865 45%, #0d5146 100%);
  cursor: pointer;
  font-size: 18px;
  font-weight: 700;
  letter-spacing: 0;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  place-items: center;
  padding: 0 28px;
  transition: transform 260ms ease, box-shadow 260ms ease, opacity 180ms ease;
  box-shadow:
    0 0 0 6px rgba(20, 107, 92, 0.12),
    0 12px 30px rgba(20, 107, 92, 0.30),
    inset 0 2px 10px rgba(255, 255, 255, 0.24);
}

.primary-button::before {
  content: "";
  position: absolute;
  inset: 2px;
  z-index: 1;
  border-radius: inherit;
  background: linear-gradient(
    180deg,
    rgba(255, 255, 255, 0.30),
    rgba(255, 255, 255, 0.10) 46%,
    rgba(255, 255, 255, 0)
  );
  pointer-events: none;
}

.primary-button::after {
  content: "";
  position: absolute;
  inset: 0;
  z-index: 2;
  border-radius: inherit;
  background-image:
    radial-gradient(circle at bottom center, rgba(255, 255, 255, 0.38) 0%, rgba(255, 255, 255, 0.16) 18%, rgba(255, 255, 255, 0.05) 36%, transparent 66%),
    radial-gradient(rgba(255, 255, 255, 0.13) 0.8px, transparent 0.8px),
    radial-gradient(rgba(0, 0, 0, 0.08) 0.7px, transparent 0.7px);
  background-size: 100% 100%, 4px 4px, 5px 5px;
  background-position: center, 0 0, 1px 3px;
  opacity: 0.52;
  mix-blend-mode: overlay;
  pointer-events: none;
}

.primary-button .button-label,
.primary-button .spinner {
  position: relative;
  z-index: 3;
}

.primary-button:hover:not(:disabled) {
  transform: translateY(-2px) scale(1.02);
  box-shadow:
    0 0 0 10px rgba(20, 107, 92, 0.16),
    0 16px 40px rgba(20, 107, 92, 0.38),
    inset 0 2px 10px rgba(255, 255, 255, 0.30);
}

.primary-button:active:not(:disabled) {
  transform: scale(0.98);
}

.primary-button:disabled {
  cursor: not-allowed;
  opacity: 0.52;
  box-shadow:
    0 0 0 4px rgba(100, 116, 108, 0.08),
    0 8px 18px rgba(100, 116, 108, 0.14),
    inset 0 2px 8px rgba(255, 255, 255, 0.18);
}

.primary-button.is-loading .button-label {
  display: none;
}

.spinner {
  display: none;
  width: 20px;
  height: 20px;
  border: 3px solid rgba(255, 255, 255, 0.45);
  border-top-color: #fff;
  border-radius: 999px;
  animation: spin 850ms linear infinite;
}

.primary-button.is-loading .spinner {
  display: block;
}

.status-text {
  min-height: 24px;
  margin: 0;
  color: var(--muted);
  line-height: 1.5;
}

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

.download-area {
  grid-template-columns: 54px 1fr;
  align-items: center;
  padding: 14px;
  border: 1px solid rgba(20, 107, 92, 0.26);
  border-radius: 8px;
  background:
    linear-gradient(145deg, rgba(255, 255, 255, 0.68), rgba(218, 242, 232, 0.94));
  box-shadow:
    inset 6px 6px 14px rgba(20, 107, 92, 0.08),
    inset -6px -6px 14px rgba(255, 255, 255, 0.82);
}

.download-button {
  width: 48px;
  height: 48px;
  border: 0;
  border-radius: 8px;
  color: #fff;
  background: linear-gradient(145deg, #d09b30, var(--accent));
  cursor: pointer;
  transition: transform 180ms ease, background-color 180ms ease;
  box-shadow:
    6px 7px 14px rgba(137, 96, 18, 0.22),
    inset 0 1px 0 rgba(255, 255, 255, 0.26);
}

.download-button:hover {
  background: #9b7021;
  transform: translateY(-1px);
}

.download-button:focus-visible,
.primary-button:focus-visible {
  outline: 3px solid rgba(20, 107, 92, 0.28);
  outline-offset: 3px;
}

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

@media (max-width: 820px) {
  .app-shell {
    width: min(100% - 20px, 680px);
    padding: 18px 0;
  }

  .converter-panel {
    grid-template-columns: 1fr;
    padding: 16px;
  }

  .liquid-ribbon-top {
    width: 220px;
    height: 96px;
    top: -42px;
    right: -18px;
  }

  .liquid-ribbon-bottom {
    width: 210px;
    height: 90px;
    right: -74px;
    bottom: -28px;
  }

  .panel-copy {
    min-height: auto;
    padding: 4px;
  }

  h1 {
    max-width: 100%;
    font-size: 42px;
  }

  .intro {
    font-size: 16px;
  }

  .file-info,
  .controls,
  .pdf-toolbar {
    grid-template-columns: 1fr;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 1ms !important;
    scroll-behavior: auto !important;
    transition-duration: 1ms !important;
  }
}