/* ── Reset & Custom Properties ─────────────────────────────────────────── */
*,
*::before,
*::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  /* Typography */
  --font: "DM Mono", ui-monospace, "Cascadia Code", monospace;
  --font-display: "Playfair Display", Georgia, serif;

  /* Shared palette */
  --accent-1: #d4922a;
  --accent-2: #f0b84a;
  --accent-gradient: linear-gradient(135deg, var(--accent-1), var(--accent-2));
  --green-1: #22c55e;
  --green-2: #10b981;
  --red: #ef4444;

  /* Transition */
  --speed: 0.3s;

  /* Ring */
  --ring-circumference: 553; /* 2π × 88 */
}

/* ── Dark theme (default) ─────────────────────────────────────────────── */
[data-theme="dark"] {
  --bg-body: #0e0c0a;
  --bg-card: #201c17;
  --bg-card-hover: #26201a;
  --bg-input: #1a1612;
  --bg-dropzone: #181410;
  --border: rgba(255,255,255,0.07);
  --border-hover: rgba(212,146,42,0.5);
  --text-primary: #ede0cc;
  --text-secondary: #9a8a78;
  --text-tertiary: #7a6e60;
  --shadow-card: 0 4px 32px rgba(0, 0, 0, 0.5), 0 0 0 1px var(--border);
  --shadow-card-hover: 0 8px 48px rgba(212, 146, 42, 0.1), 0 0 0 1px var(--border-hover);
  --progress-track: #2a221a;
  --ring-bg: #2a221a;
  --glow-accent: rgba(212, 146, 42, 0.12);
}

/* ── Light theme ──────────────────────────────────────────────────────── */
[data-theme="light"] {
  --bg-body: #f5f0e8;
  --bg-card: #faf6ef;
  --bg-card-hover: #fff;
  --bg-input: #ede5d6;
  --bg-dropzone: #f2ece0;
  --border: rgba(0,0,0,0.08);
  --border-hover: rgba(184,112,32,0.45);
  --text-primary: #2a1f0e;
  --text-secondary: #6a5a48;
  --text-tertiary: #8a7a68;
  --shadow-card: 0 4px 24px rgba(0, 0, 0, 0.06), 0 0 0 1px var(--border);
  --shadow-card-hover: 0 8px 48px rgba(184, 112, 32, 0.1), 0 0 0 1px var(--border-hover);
  --progress-track: #e0d8cc;
  --ring-bg: #e0d8cc;
  --glow-accent: rgba(184, 112, 32, 0.07);
}

/* ── Base ──────────────────────────────────────────────────────────────── */
html {
  font-size: 16px;
  scroll-behavior: smooth;
}

body {
  font-family: var(--font);
  background: var(--bg-body);
  color: var(--text-primary);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  transition: background var(--speed), color var(--speed);
  -webkit-font-smoothing: antialiased;
  position: relative;
}

/* Noise texture overlay */
body::before {
  content: '';
  position: fixed;
  inset: 0;
  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='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)' opacity='0.04'/%3E%3C/svg%3E");
  background-size: 200px 200px;
  pointer-events: none;
  z-index: 1000;
  opacity: 0.5;
}

/* Warm center glow */
body::after {
  content: '';
  position: fixed;
  inset: 0;
  background: radial-gradient(ellipse 70% 60% at 50% 45%, rgba(180, 100, 20, 0.06) 0%, transparent 70%);
  pointer-events: none;
  z-index: 0;
}

/* ── Theme Toggle ─────────────────────────────────────────────────────── */
.theme-toggle {
  position: fixed;
  top: 1.25rem;
  right: 1.25rem;
  z-index: 100;
  width: 44px;
  height: 44px;
  border: 1px solid var(--border);
  border-radius: 12px;
  background: var(--bg-card);
  color: var(--text-secondary);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all var(--speed);
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
}

.theme-toggle:hover {
  border-color: var(--accent-1);
  color: var(--accent-1);
  transform: scale(1.05);
  box-shadow: 0 4px 16px rgba(212, 146, 42, 0.2);
}

.theme-icon {
  width: 20px;
  height: 20px;
}

.hidden {
  display: none !important;
}

/* ── Layout ───────────────────────────────────────────────────────────── */
.container {
  flex: 1;
  width: 100%;
  max-width: 560px;
  margin: 0 auto;
  padding: 2rem 1.25rem 4rem;
  position: relative;
  z-index: 1;
}

/* ── Hero ──────────────────────────────────────────────────────────────── */
.hero {
  text-align: center;
  margin-bottom: 2.5rem;
}

.logo-mark {
  width: 64px;
  height: 64px;
  margin: 0 auto 1.25rem;
  animation: spin-slow 20s linear infinite;
}

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

.hero-title {
  font-family: var(--font-display);
  font-size: 2rem;
  font-weight: 700;
  letter-spacing: 0.02em;
  line-height: 1.2;
}

.accent {
  background: var(--accent-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-sub {
  margin-top: 0.5rem;
  font-size: 1rem;
  color: var(--text-secondary);
  font-weight: 400;
}

/* ── Cards ─────────────────────────────────────────────────────────────── */
.card {
  background: var(--bg-card);
  border-radius: 20px;
  padding: 2rem;
  box-shadow: var(--shadow-card);
  transition: all var(--speed);
  animation: card-in 0.5s ease-out;
}

@keyframes card-in {
  from {
    opacity: 0;
    transform: translateY(20px) scale(0.97);
  }
  to {
    opacity: 1;
    transform: translateY(0) scale(1);
  }
}

/* ── Drop Zone ─────────────────────────────────────────────────────────── */
.drop-zone {
  border: 2px dashed var(--border);
  border-radius: 16px;
  padding: 3rem 2rem;
  text-align: center;
  cursor: pointer;
  transition: all var(--speed);
  background: var(--bg-dropzone);
  position: relative;
  overflow: hidden;
}

.drop-zone::before {
  content: "";
  position: absolute;
  inset: 0;
  background: var(--accent-gradient);
  opacity: 0;
  transition: opacity var(--speed);
  border-radius: inherit;
}

.drop-zone:hover,
.drop-zone.drag-over {
  border-color: var(--accent-1);
  background: var(--bg-card-hover);
}

.drop-zone:hover::before,
.drop-zone.drag-over::before {
  opacity: 0.04;
}

.drop-zone-content {
  position: relative;
  z-index: 1;
}

.upload-icon {
  width: 48px;
  height: 48px;
  color: var(--text-tertiary);
  margin-bottom: 1rem;
  transition: color var(--speed), transform var(--speed);
}

.drop-zone:hover .upload-icon {
  color: var(--accent-1);
  transform: translateY(-4px);
}

.drop-label {
  font-size: 1.05rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 0.35rem;
}

.drop-hint {
  font-size: 0.85rem;
  color: var(--text-tertiary);
}

/* ── File Info ──────────────────────────────────────────────────────────── */
.file-info {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin-top: 1.25rem;
  padding: 0.85rem 1rem;
  border-radius: 12px;
  background: var(--bg-input);
  border: 1px solid var(--border);
  animation: fade-in 0.3s ease;
}

@keyframes fade-in {
  from { opacity: 0; transform: translateY(8px); }
  to { opacity: 1; transform: translateY(0); }
}

.file-info-icon {
  flex-shrink: 0;
  width: 36px;
  height: 36px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 10px;
  background: var(--accent-gradient);
  color: #fff;
}

.file-info-icon svg {
  width: 18px;
  height: 18px;
}

.file-info-details {
  flex: 1;
  min-width: 0;
  display: flex;
  flex-direction: column;
}

.file-name {
  font-size: 0.9rem;
  font-weight: 600;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.file-size {
  font-size: 0.78rem;
  color: var(--text-tertiary);
}

.file-remove {
  flex-shrink: 0;
  width: 28px;
  height: 28px;
  border: none;
  background: transparent;
  color: var(--text-tertiary);
  font-size: 1.2rem;
  cursor: pointer;
  border-radius: 8px;
  transition: all var(--speed);
  display: flex;
  align-items: center;
  justify-content: center;
}

.file-remove:hover {
  background: rgba(239, 68, 68, 0.1);
  color: var(--red);
}

/* ── Settings ──────────────────────────────────────────────────────────── */
.settings-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
  margin-top: 1.5rem;
}

.setting label {
  display: block;
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--text-secondary);
  margin-bottom: 0.4rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.optional {
  font-weight: 400;
  text-transform: none;
  letter-spacing: 0;
  color: var(--text-tertiary);
}

.setting input {
  width: 100%;
  padding: 0.65rem 0.85rem;
  border: 1px solid var(--border);
  border-radius: 10px;
  background: var(--bg-input);
  color: var(--text-primary);
  font-size: 0.95rem;
  font-family: var(--font);
  transition: all var(--speed);
  outline: none;
}

.setting input:focus {
  border-color: var(--accent-1);
  box-shadow: 0 0 0 3px var(--glow-accent);
}

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

/* ── Buttons ───────────────────────────────────────────────────────────── */
.btn-primary {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  width: 100%;
  margin-top: 1.5rem;
  padding: 0.9rem 1.5rem;
  font-size: 1rem;
  font-weight: 700;
  font-family: var(--font);
  border: none;
  border-radius: 14px;
  background: var(--accent-gradient);
  color: #fff;
  cursor: pointer;
  transition: all var(--speed);
  position: relative;
  overflow: hidden;
  text-decoration: none;
}

.btn-primary::before {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(255,255,255,0.15), transparent);
  opacity: 0;
  transition: opacity var(--speed);
}

.btn-primary:hover:not(:disabled)::before {
  opacity: 1;
}

.btn-primary:hover:not(:disabled) {
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(212, 146, 42, 0.35);
}

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

.btn-primary:disabled {
  opacity: 0.4;
  cursor: not-allowed;
}

.btn-arrow {
  width: 20px;
  height: 20px;
  transition: transform var(--speed);
}

.btn-primary:hover:not(:disabled) .btn-arrow {
  transform: translateX(4px);
}

.btn-secondary {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.8rem 1.5rem;
  font-size: 0.95rem;
  font-weight: 600;
  font-family: var(--font);
  border: 1px solid var(--border);
  border-radius: 14px;
  background: var(--bg-card);
  color: var(--text-primary);
  cursor: pointer;
  transition: all var(--speed);
}

.btn-secondary:hover {
  border-color: var(--accent-1);
  background: var(--bg-card-hover);
  transform: translateY(-1px);
}

/* ── Stage Tracker ─────────────────────────────────────────────────────── */
.stage-tracker {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0;
  margin-bottom: 2rem;
}

.stage-pill {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.5rem 1rem;
  border-radius: 100px;
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--text-tertiary);
  background: var(--bg-input);
  border: 1px solid var(--border);
  transition: all 0.5s ease;
}

.stage-pill.active {
  color: #0e0c0a;
  background: var(--accent-gradient);
  border-color: transparent;
  box-shadow: 0 4px 16px rgba(212, 146, 42, 0.3);
}

.stage-pill.done {
  color: var(--green-1);
  border-color: var(--green-1);
  background: rgba(34, 197, 94, 0.08);
}

.stage-num {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 22px;
  height: 22px;
  border-radius: 50%;
  font-size: 0.72rem;
  font-weight: 700;
  background: rgba(255, 255, 255, 0.15);
}

.stage-pill:not(.active) .stage-num {
  background: var(--bg-body);
}

.stage-pill.done .stage-num {
  background: rgba(34, 197, 94, 0.15);
}

.stage-connector {
  width: 24px;
  height: 2px;
  background: var(--border);
  transition: background 0.5s ease;
}

.stage-connector.active {
  background: var(--accent-gradient);
}

/* ── Circular Progress Ring ────────────────────────────────────────────── */
.progress-ring-wrapper {
  position: relative;
  width: 180px;
  height: 180px;
  margin: 0 auto 1.5rem;
}

.progress-ring {
  width: 100%;
  height: 100%;
  transform: rotate(-90deg);
}

.progress-ring-bg {
  fill: none;
  stroke: var(--ring-bg);
  stroke-width: 8;
}

.progress-ring-fill {
  fill: none;
  stroke: url(#grad);
  stroke-width: 8;
  stroke-linecap: round;
  stroke-dasharray: var(--ring-circumference);
  stroke-dashoffset: var(--ring-circumference);
  transition: stroke-dashoffset 0.4s ease;
  filter: drop-shadow(0 0 8px rgba(212, 146, 42, 0.4));
}

.progress-ring-text {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
}

.progress-percent {
  font-size: 2.8rem;
  font-weight: 800;
  letter-spacing: -0.03em;
  background: var(--accent-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.progress-percent-sign {
  font-size: 1.4rem;
  font-weight: 700;
  color: var(--text-tertiary);
  margin-top: 0.3rem;
}

/* ── Progress Bar ──────────────────────────────────────────────────────── */
.progress-bar-wrapper {
  margin-bottom: 1.5rem;
}

.progress-bar-track {
  width: 100%;
  height: 6px;
  border-radius: 100px;
  background: var(--progress-track);
  overflow: hidden;
  position: relative;
}

.progress-bar-fill {
  height: 100%;
  width: 0%;
  border-radius: 100px;
  background: var(--accent-gradient);
  transition: width 0.4s ease;
  position: relative;
}

.progress-bar-fill::after {
  content: "";
  position: absolute;
  right: 0;
  top: -2px;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--accent-2);
  box-shadow: 0 0 12px rgba(240, 184, 74, 0.6);
  opacity: 0;
  transition: opacity 0.3s;
}

.progress-bar-fill:not([style*="width: 0%"])::after,
.progress-bar-fill:not([style*="width:0%"])::after {
  opacity: 1;
}

/* ── Progress Detail ───────────────────────────────────────────────────── */
.progress-detail {
  text-align: center;
  font-size: 0.88rem;
  color: var(--text-secondary);
  min-height: 1.4em;
}

.overall-progress {
  text-align: center;
  margin-top: 0.75rem;
}

.overall-text {
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--text-tertiary);
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

/* ── Done Card ─────────────────────────────────────────────────────────── */
.done-card {
  text-align: center;
}

.done-icon-container {
  margin-bottom: 1.25rem;
  animation: pop-in 0.5s cubic-bezier(0.34, 1.56, 0.64, 1);
}

@keyframes pop-in {
  from {
    opacity: 0;
    transform: scale(0.5);
  }
  to {
    opacity: 1;
    transform: scale(1);
  }
}

.done-check {
  width: 72px;
  height: 72px;
}

.done-title {
  font-size: 1.4rem;
  font-weight: 700;
  margin-bottom: 0.35rem;
}

.done-sub {
  font-size: 0.92rem;
  color: var(--text-secondary);
  margin-bottom: 1.5rem;
}

.done-actions {
  display: flex;
  gap: 0.75rem;
}

.done-actions .btn-primary,
.done-actions .btn-secondary {
  flex: 1;
  height: 3.2rem;
  padding: 0 1.5rem;
  margin: 0;
}


/* ── Error Card ────────────────────────────────────────────────────────── */
.error-card {
  text-align: center;
  display: flex;
  flex-direction: column;
  align-items: center;
}

.error-icon-container {
  margin-bottom: 1.25rem;
  animation: shake 0.5s ease;
}

@keyframes shake {
  0%, 100% { transform: translateX(0); }
  20% { transform: translateX(-8px); }
  40% { transform: translateX(8px); }
  60% { transform: translateX(-6px); }
  80% { transform: translateX(4px); }
}

.error-title {
  font-size: 1.3rem;
  font-weight: 700;
  color: var(--red);
  margin-bottom: 0.5rem;
}

.error-detail {
  font-size: 0.9rem;
  color: var(--text-secondary);
  margin-bottom: 1.5rem;
  word-break: break-word;
}

/* ── API Overlay ───────────────────────────────────────────────────────── */
.api-overlay {
  position: fixed;
  inset: 0;
  z-index: 1001;
  background: var(--bg-body);
  display: flex;
  align-items: center;
  justify-content: center;
  transition: opacity 0.4s ease;
}

.api-overlay.fade-out {
  opacity: 0;
  pointer-events: none;
}

.api-overlay-content {
  text-align: center;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1.25rem;
}

.api-spinner {
  width: 40px;
  height: 40px;
  border: 3px solid var(--border);
  border-top-color: var(--accent-1);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}

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

.api-status-text {
  font-size: 0.95rem;
  color: var(--text-secondary);
  font-weight: 500;
}

.api-status-text.error {
  color: var(--red);
}

/* ── Transfer Progress (Upload / Download) ─────────────────────────────── */
.transfer-progress {
  margin-bottom: 1.5rem;
  animation: fade-in 0.3s ease;
}

.transfer-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 0.65rem;
}

.transfer-label {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--text-primary);
}

.transfer-icon {
  width: 18px;
  height: 18px;
  color: var(--accent-1);
  flex-shrink: 0;
}

.transfer-stats {
  font-size: 0.8rem;
  font-weight: 500;
  color: var(--text-tertiary);
  font-variant-numeric: tabular-nums;
}

.transfer-bar-track {
  width: 100%;
  height: 8px;
  border-radius: 100px;
  background: var(--progress-track);
  overflow: hidden;
  position: relative;
}

.transfer-bar-fill {
  height: 100%;
  width: 0%;
  border-radius: 100px;
  transition: width 0.3s ease;
  position: relative;
}

.transfer-bar-fill.upload-fill {
  background: linear-gradient(90deg, #d4922a, #f0b84a, #d4922a);
  background-size: 200% 100%;
  animation: shimmer-bar 2s ease-in-out infinite;
}

.transfer-bar-fill.download-fill {
  background: linear-gradient(90deg, #22c55e, #4ade80, #10b981);
  background-size: 200% 100%;
  animation: shimmer-bar 2s ease-in-out infinite;
}

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

.transfer-bar-fill::after {
  content: "";
  position: absolute;
  right: 0;
  top: -1px;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  opacity: 0;
  transition: opacity 0.3s;
}

.transfer-bar-fill.upload-fill::after {
  background: var(--accent-2);
  box-shadow: 0 0 10px rgba(240, 184, 74, 0.6);
}

.transfer-bar-fill.download-fill::after {
  background: var(--green-1);
  box-shadow: 0 0 10px rgba(34, 197, 94, 0.6);
}

.transfer-bar-fill:not([style*="width: 0%"])::after,
.transfer-bar-fill:not([style*="width:0%"])::after {
  opacity: 1;
}

.transfer-sub {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-top: 0.5rem;
  font-size: 0.78rem;
  font-weight: 600;
  color: var(--text-secondary);
  font-variant-numeric: tabular-nums;
}

.transfer-speed {
  color: var(--text-tertiary);
  font-weight: 500;
}

.transfer-progress.complete .transfer-bar-fill {
  animation: none;
}

.transfer-progress.complete .transfer-bar-fill.upload-fill {
  background: var(--accent-gradient);
}

.transfer-progress.complete .transfer-bar-fill.download-fill {
  background: linear-gradient(135deg, #22c55e, #10b981);
}

/* ── Responsive ────────────────────────────────────────────────────────── */
@media (max-width: 480px) {
  .container {
    padding: 1.5rem 1rem 3rem;
  }
  .hero-title {
    font-size: 1.6rem;
  }
  .card {
    padding: 1.5rem;
    border-radius: 16px;
  }
  .settings-grid {
    grid-template-columns: 1fr;
  }
  .stage-pill {
    padding: 0.4rem 0.65rem;
    font-size: 0.72rem;
  }
  .stage-label {
    display: none;
  }
  .done-actions {
    flex-direction: column;
  }
}

/* ── Particle / Glow accents ───────────────────────────────────────────── */
.upload-card {
  position: relative;
}

.upload-card::after {
  content: "";
  position: absolute;
  top: -1px;
  left: 20%;
  right: 20%;
  height: 2px;
  background: var(--accent-gradient);
  border-radius: 100px;
  opacity: 0;
  transition: opacity var(--speed);
}

.upload-card:hover::after {
  opacity: 0.6;
}

/* Processing glow */
.progress-card {
  position: relative;
}

.progress-card::before {
  content: "";
  position: absolute;
  inset: -1px;
  border-radius: 20px;
  background: var(--accent-gradient);
  z-index: -1;
  opacity: 0.15;
  animation: pulse-glow 2s ease-in-out infinite;
}

@keyframes pulse-glow {
  0%, 100% { opacity: 0.1; }
  50% { opacity: 0.2; }
}