/* ─────────────────────────────────────────────────────────
   FiiO DAC Control — Offline  |  style.css  v3
   ───────────────────────────────────────────────────────── */

:root {
  --bg:        #0e0e10;
  --bg2:       #18181c;
  --bg3:       #22222a;
  --border:    #2e2e3a;
  --accent:    #e8423a;
  --accent2:   #ff6b5e;
  --text:      #e8e8f0;
  --text-dim:  #7878a0;
  --text-xdim: #44445a;
  --green:     #3ddc84;
  --yellow:    #ffd060;
  --radius:    10px;
  --radius-sm: 6px;
  --shadow:    0 4px 24px rgba(0,0,0,.45);
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { font-size: 14px; }
body {
  background: var(--bg);
  color: var(--text);
  font-family: 'Segoe UI', system-ui, sans-serif;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

button:focus-visible,
input:focus-visible,
select:focus-visible {
  outline: 2px solid var(--accent2);
  outline-offset: 2px;
}

/* ── HEADER ── */
header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 14px 28px;
  background: var(--bg2);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 100;
  gap: 12px;
}
.header-left { display: flex; align-items: center; gap: 10px; flex-shrink: 0; }
.logo-mark   { font-size: 22px; color: var(--accent); }
.app-title   { font-size: 16px; font-weight: 700; letter-spacing: .5px; }
.app-sub     {
  font-size: 11px; color: var(--text-dim);
  background: var(--bg3); padding: 2px 8px;
  border-radius: 20px; border: 1px solid var(--border);
}
.header-right { display: flex; align-items: center; gap: 10px; }
.device-name {
  font-size: 12px; color: var(--text-dim);
  background: var(--bg3); padding: 4px 12px;
  border-radius: 20px; border: 1px solid var(--border);
  max-width: 200px; overflow: hidden; text-overflow: ellipsis; white-space: nowrap;
}

/* Feature D: queue depth badge */
.queue-badge {
  font-size: 11px; color: var(--yellow);
  background: rgba(255, 208, 96, 0.12);
  border: 1px solid rgba(255, 208, 96, 0.3);
  padding: 2px 10px; border-radius: 20px;
  animation: pulse 1.5s ease-in-out infinite;
}
@keyframes pulse { 0%,100%{opacity:1} 50%{opacity:.55} }

/* ── STATUS BAR ── */
.status-bar {
  padding: 7px 28px; font-size: 12px;
  border-bottom: 1px solid var(--border);
  transition: background .3s;
}
.status-idle    { background: var(--bg2); color: var(--text-dim); }
.status-ok      { background: #0d2a1a;   color: var(--green); }
.status-error   { background: #2a0d0d;   color: #ff6b6b; }
.status-working { background: #1a1a2a;   color: var(--yellow); }

/* ── BUTTONS ── */
.btn {
  padding: 7px 16px; border: none; border-radius: var(--radius-sm);
  cursor: pointer; font-size: 13px; font-weight: 600;
  transition: opacity .15s, transform .1s; white-space: nowrap;
}
.btn:active:not(:disabled) { transform: scale(.96); }
.btn:disabled { opacity: .35; cursor: not-allowed; }
.btn-primary   { background: var(--accent); color: #fff; }
.btn-primary:hover:not(:disabled)   { background: var(--accent2); }
.btn-danger    { background: #3a1a1a; color: #ff6b6b; border: 1px solid #5a2a2a; }
.btn-danger:hover:not(:disabled)    { background: #4a2020; }
.btn-secondary { background: var(--bg3); color: var(--text); border: 1px solid var(--border); }
.btn-secondary:hover:not(:disabled) { background: #2a2a36; }
.btn-ghost     { background: transparent; color: var(--text-dim); border: 1px solid var(--border); }
.btn-ghost:hover:not(:disabled)     { color: var(--text); border-color: #4a4a60; }
.btn-sm        { padding: 3px 10px; font-size: 11px; }

/* ── CONNECTION MODE + REMOTE BACKEND ── */
.conn-mode {
  display: flex; gap: 4px;
  background: var(--bg3); border: 1px solid var(--border);
  border-radius: var(--radius-sm); padding: 2px;
}
.conn-mode-btn {
  border: none; background: transparent; color: var(--text-dim);
  font-size: 11px; font-weight: 600; padding: 3px 10px;
  border-radius: calc(var(--radius-sm) - 2px);
  cursor: pointer; white-space: nowrap;
}
.conn-mode-btn:hover { color: var(--text); }
.conn-mode-btn.active { background: var(--accent); color: #fff; }

.remote-config {
  display: flex; align-items: center; gap: 8px; flex-wrap: wrap;
  padding: 8px 28px; background: var(--bg2);
  border-bottom: 1px solid var(--border); font-size: 12px;
}
.remote-config-label { color: var(--text-dim); white-space: nowrap; }
.remote-url {
  width: 220px; padding: 5px 10px; font-size: 12px;
  background: var(--bg3); color: var(--text);
  border: 1px solid var(--border); border-radius: var(--radius-sm);
}
.remote-device-list {
  min-width: 220px; padding: 5px 10px; font-size: 12px;
  background: var(--bg3); color: var(--text);
  border: 1px solid var(--border); border-radius: var(--radius-sm);
}
.remote-status { color: var(--text-dim); font-size: 12px; }

@media (max-width: 720px) {
  .header-right { flex-wrap: wrap; }
  .remote-url, .remote-device-list { width: 160px; min-width: 160px; }
}

/* ── TOGGLE ── */
.toggle-group { display: flex; gap: 4px; }
.toggle-btn {
  padding: 5px 18px; border-radius: var(--radius-sm);
  border: 1px solid var(--border); background: var(--bg3);
  color: var(--text-dim); cursor: pointer; font-size: 12px; font-weight: 700;
  transition: all .15s;
}
.toggle-btn.active { background: var(--accent); color: #fff; border-color: var(--accent); }
.toggle-btn:disabled { opacity: .35; cursor: not-allowed; }

/* ── KEYBOARD SHORTCUT HINT (Feature J) ── */
.shortcut-hint {
  font-size: 11px; color: var(--text-xdim);
  margin-top: 14px; padding-top: 12px;
  border-top: 1px solid var(--border);
}
kbd {
  display: inline-block;
  background: var(--bg3); border: 1px solid var(--border);
  border-radius: 3px; padding: 1px 5px;
  font-family: monospace; font-size: 10px;
  color: var(--text-dim);
}

/* ── LAYOUT ── */
.main {
  display: flex; flex-direction: column; gap: 18px;
  padding: 24px 28px; max-width: 1100px; width: 100%; margin: 0 auto;
}

/* ── CARDS ── */
.card {
  background: var(--bg2); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 20px 24px; box-shadow: var(--shadow);
}
.card-title {
  font-size: 11px; font-weight: 700; text-transform: uppercase;
  letter-spacing: 1.5px; color: var(--text-dim); margin-bottom: 16px;
}

/* ── VISUALIZER CANVAS ── */
.visualizer-card { padding-bottom: 12px; }
.eq-canvas {
  display: block; width: 100%; height: 300px;
  border-radius: var(--radius-sm);
  background: #09090c; border: 1px solid var(--border);
}

/* ── GLOBAL CONTROLS ── */
.control-row { display: flex; align-items: center; gap: 16px; margin-bottom: 16px; }
.control-row:last-child { margin-bottom: 0; }
.control-label {
  min-width: 140px; font-size: 13px; color: var(--text);
  display: flex; align-items: center; gap: 8px;
}
.value-badge {
  background: var(--bg3); border: 1px solid var(--border);
  padding: 2px 8px; border-radius: 20px;
  font-size: 11px; color: var(--accent2); font-weight: 700;
  min-width: 62px; text-align: center;
}
.btn-row { gap: 10px; flex-wrap: wrap; }

/* ── SLIDERS ── */
input[type=range] {
  -webkit-appearance: none; appearance: none;
  height: 4px; border-radius: 2px; background: var(--bg3); outline: none; cursor: pointer;
}
input[type=range]::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 16px; height: 16px; border-radius: 50%;
  background: var(--accent); cursor: pointer;
  border: 2px solid var(--bg2); transition: transform .15s;
}
input[type=range]::-webkit-slider-thumb:hover { transform: scale(1.2); }
input[type=range]:disabled { opacity: .3; cursor: not-allowed; }
.slider-wide { flex: 1; }

/* ── BUILT-IN PRESETS ── */
.builtin-presets { display: flex; flex-wrap: wrap; gap: 8px; }
.builtin-btn {
  padding: 6px 18px; border-radius: 20px;
  border: 1px solid var(--border); background: var(--bg3);
  color: var(--text-dim); cursor: pointer; font-size: 12px; font-weight: 600;
  transition: all .15s;
}
.builtin-btn:hover  { border-color: var(--accent); color: var(--text); }
.builtin-btn.active { background: var(--accent); color: #fff; border-color: var(--accent); }

/* ── EQ BANDS ── */
.eq-bands {
  display: flex; gap: 8px; align-items: flex-end;
  overflow-x: auto; padding-bottom: 8px;
  scrollbar-color: var(--border) transparent;
}

/* Feature H: gain tint transition */
.eq-band {
  display: flex; flex-direction: column; align-items: center;
  flex: 1; min-width: 72px;
  background: var(--bg3); border: 1px solid var(--border);
  border-radius: var(--radius-sm); padding: 10px 6px 8px; gap: 6px;
  transition: border-color .2s, background .3s;
}
.eq-band:hover   { border-color: #4a4a60; }
.eq-band.changed { border-color: var(--accent); }

.band-freq {
  font-size: 11px; font-weight: 700; color: var(--text-dim); text-align: center;
  /* Fix B: transitions when label updates */
  transition: color .2s;
}
.band-slider-wrap {
  position: relative; height: 140px;
  display: flex; align-items: center; justify-content: center;
}
input.vslider {
  writing-mode: vertical-lr; direction: rtl;
  width: 4px; height: 130px; cursor: pointer; background: var(--bg);
}
input.vslider::-webkit-slider-thumb { width: 14px; height: 14px; }
.zero-line {
  position: absolute; left: 0; right: 0; top: 50%;
  height: 1px; background: var(--border); pointer-events: none;
}
.band-gain-val {
  font-size: 12px; font-weight: 700; color: var(--accent2);
  min-height: 18px; text-align: center;
}
.band-controls { display: flex; flex-direction: column; gap: 4px; width: 100%; }
.band-controls label {
  font-size: 9px; color: var(--text-xdim);
  text-transform: uppercase; letter-spacing: .8px;
}
.band-controls select,
.band-controls input[type=number] {
  width: 100%; background: var(--bg); border: 1px solid var(--border);
  color: var(--text); border-radius: 4px; padding: 2px 4px;
  font-size: 11px; outline: none;
}
.band-controls select:focus,
.band-controls input[type=number]:focus { border-color: var(--accent); }
.band-send-btn {
  width: 100%; padding: 4px 0; font-size: 11px; border-radius: 4px;
  border: 1px solid var(--border); background: var(--bg); color: var(--text-dim);
  cursor: pointer; transition: all .15s;
}
.band-send-btn:hover:not(:disabled) { background: var(--accent); color: #fff; border-color: var(--accent); }
.band-send-btn:disabled { opacity: .3; cursor: not-allowed; }

/* ── LOCAL PRESETS ── */
.presets-header  { display: flex; justify-content: space-between; align-items: center; }
.preset-actions  { display: flex; gap: 6px; }
.preset-row      { display: flex; gap: 8px; margin-bottom: 12px; }
.preset-input {
  flex: 1; background: var(--bg3); border: 1px solid var(--border);
  color: var(--text); border-radius: var(--radius-sm);
  padding: 7px 12px; font-size: 13px; outline: none;
}
.preset-input:focus { border-color: var(--accent); }
.preset-list { display: flex; flex-wrap: wrap; gap: 8px; min-height: 36px; }
.preset-chip {
  display: flex; align-items: center; gap: 6px;
  background: var(--bg3); border: 1px solid var(--border);
  border-radius: var(--radius-sm); padding: 6px 6px 6px 14px;
  cursor: pointer; transition: border-color .15s;
}
.preset-chip:hover { border-color: var(--accent); }
.chip-info { display: flex; flex-direction: column; gap: 1px; }
.preset-chip-name { font-size: 12px; color: var(--text); }
.chip-date        { font-size: 10px; color: var(--text-xdim); }
.preset-chip-del {
  background: none; border: none; color: var(--text-dim);
  cursor: pointer; font-size: 14px; line-height: 1; padding: 0 4px;
  border-radius: 50%; transition: color .15s;
}
.preset-chip-del:hover { color: #ff6b6b; }

/* ── USB LOG ── */
.log-header { display: flex; justify-content: space-between; align-items: center; }
.log-box {
  background: #09090c; border: 1px solid var(--border);
  border-radius: var(--radius-sm); padding: 10px 14px;
  font-family: 'Consolas', 'Fira Code', monospace; font-size: 11px;
  height: 160px; overflow-y: auto; color: var(--text-dim);
}
.log-entry      { padding: 1px 0; }
.log-entry.tx   { color: #5fbfff; }
.log-entry.rx   { color: var(--green); }
.log-entry.err  { color: #ff6b6b; }
.log-entry.warn { color: var(--yellow); }
.log-entry.inf  { color: var(--text-dim); }
.log-ts         { color: var(--text-xdim); margin-right: 6px; }

/* ── TOAST NOTIFICATIONS (Feature G) ── */
#toast-root {
  position: fixed; bottom: 24px; right: 24px;
  display: flex; flex-direction: column; gap: 10px;
  z-index: 9999; pointer-events: none;
}
.toast {
  padding: 10px 18px; border-radius: var(--radius-sm);
  font-size: 13px; font-weight: 500;
  border: 1px solid var(--border);
  background: var(--bg2);
  box-shadow: 0 4px 20px rgba(0,0,0,.6);
  opacity: 0;
  transform: translateY(10px);
  transition: opacity .22s ease, transform .22s ease;
  pointer-events: auto;
}
.toast-show { opacity: 1; transform: translateY(0); }
.toast-ok    { border-color: var(--green);  color: var(--green); }
.toast-info  { border-color: var(--border); color: var(--text);  }
.toast-warn  { border-color: var(--yellow); color: var(--yellow); }
.toast-error { border-color: #ff6b6b;       color: #ff6b6b; }

@media (max-width: 820px) {
  header,
  .control-row,
  .presets-header,
  .log-header {
    flex-wrap: wrap;
  }

  header {
    padding: 12px 16px;
  }

  .status-bar,
  .main {
    padding-left: 16px;
    padding-right: 16px;
  }

  .main {
    padding-top: 16px;
    padding-bottom: 16px;
  }

  .control-label {
    min-width: 0;
    width: 100%;
    justify-content: space-between;
  }

  .slider-wide {
    width: 100%;
  }

  .preset-row {
    flex-direction: column;
  }

  .preset-row .btn {
    width: 100%;
  }

  .preset-actions {
    width: 100%;
    flex-wrap: wrap;
  }

  .eq-band {
    min-width: 88px;
  }
}