:root {
  --bg: #121317;
  --panel: #1c1e26;
  --text: #eaeaf0;
  --faded: rgba(234, 234, 240, 0.32);
  --accent: #4f8cff;
  --pivot: #ff4747;
  --border: #2c2f3a;
}

* {
  box-sizing: border-box;
}

html, body {
  height: 100%;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

.topbar {
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 14px 24px;
  background: var(--panel);
  border-bottom: 1px solid var(--border);
}

.topbar h1 {
  font-size: 18px;
  margin: 0;
  margin-right: auto;
  font-weight: 600;
  letter-spacing: 0.5px;
}

.file-btn {
  position: relative;
  background: var(--accent);
  color: #fff;
  padding: 9px 18px;
  border-radius: 6px;
  cursor: pointer;
  font-size: 14px;
  font-weight: 500;
  overflow: hidden;
}

.file-btn input[type="file"] {
  position: absolute;
  inset: 0;
  opacity: 0;
  cursor: pointer;
}

.file-status {
  font-size: 13px;
  color: var(--faded);
  min-width: 160px;
}

.reader {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 40px;
  padding: 24px;
}

.word-row {
  display: flex;
  align-items: baseline;
  justify-content: center;
  width: 100%;
  max-width: 1100px;
}

.prev-word,
.next-word {
  width: 26vw;
  max-width: 320px;
  font-size: clamp(18px, 2.4vw, 30px);
  color: var(--faded);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.prev-word {
  text-align: right;
  padding-right: 18px;
}

.next-word {
  text-align: left;
  padding-left: 18px;
}

.current-box {
  width: min(90vw, 600px);
  flex-shrink: 0;
  border-left: 1px solid var(--border);
  border-right: 1px solid var(--border);
  padding: 10px 0 10px 24px;
  text-align: left;
}

.current-word {
  font-size: clamp(32px, 5.5vw, 64px);
  font-weight: 600;
  white-space: nowrap;
}

.current-word .pivot {
  color: var(--pivot);
}

.progress-wrap {
  width: min(90vw, 700px);
}

.progress-wrap input[type="range"] {
  width: 100%;
  accent-color: var(--accent);
}

.progress-info {
  display: flex;
  justify-content: space-between;
  font-size: 13px;
  color: var(--faded);
  margin-top: 6px;
}

.controls {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 20px;
  padding: 18px 24px 28px;
  background: var(--panel);
  border-top: 1px solid var(--border);
  flex-wrap: wrap;
}

.controls button {
  background: #2a2d38;
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: 8px;
  font-size: 20px;
  width: 48px;
  height: 44px;
  cursor: pointer;
  transition: background 0.15s;
}

.controls button:hover:not(:disabled) {
  background: var(--accent);
}

.controls button:disabled {
  opacity: 0.4;
  cursor: not-allowed;
}

.wpm-control {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 13px;
  color: var(--faded);
}

.wpm-control label {
  white-space: nowrap;
}

.wpm-control input[type="number"] {
  width: 70px;
  background: #2a2d38;
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 6px 8px;
  font-size: 14px;
}

.wpm-control input[type="range"] {
  width: 140px;
  accent-color: var(--accent);
}

@media (max-width: 640px) {
  .prev-word, .next-word {
    display: none;
  }
  .current-box {
    border: none;
    padding-left: 0;
    text-align: center;
  }
  .current-word {
    white-space: normal;
  }
}