:root {
  --bg: #f3f5f7;
  --surface: #ffffff;
  --text: #1f2933;
  --muted: #6b7a8c;
  --accent: #0d6e6e;
  --border: #d8e0e7;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  background: radial-gradient(circle at top right, #e0f2f1, var(--bg));
  color: var(--text);
  font-family: "Segoe UI", Tahoma, sans-serif;
}

.app-shell {
  max-width: 1100px;
  margin: 0 auto;
  padding: 24px;
}

header {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
}

h1 {
  margin: 0;
}

.tabs {
  display: inline-flex;
  gap: 8px;
}

.tab {
  border: 1px solid var(--border);
  background: var(--surface);
  color: var(--text);
  border-radius: 8px;
  padding: 10px 14px;
  cursor: pointer;
}

.tab.active {
  border-color: var(--accent);
  color: #fff;
  background: var(--accent);
}

main {
  margin-top: 20px;
}

.panel {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 16px;
}

.video-layout {
  display: grid;
  gap: 18px;
  grid-template-columns: 1.6fr 1fr;
}

#player {
  width: 100%;
  background: #000;
  border-radius: 10px;
  max-height: 70vh;
}

#current-title {
  margin: 12px 0 0;
  font-size: 1.1rem;
}

.list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.list button,
.list a {
  width: 100%;
  text-align: left;
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 10px 12px;
  background: #fbfcfd;
  color: var(--text);
  text-decoration: none;
  display: block;
}

.list button.active {
  border-color: var(--accent);
  background: #e6f4f4;
}

.muted {
  color: var(--muted);
}

@media (max-width: 860px) {
  .video-layout {
    grid-template-columns: 1fr;
  }
}

.downloader {
  margin-top: 16px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 16px;
}

.downloader form {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.downloader input {
  flex: 1 1 200px;
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 10px 12px;
}

.downloader button {
  border: 1px solid var(--accent);
  background: var(--accent);
  color: #fff;
  border-radius: 8px;
  padding: 10px 16px;
  cursor: pointer;
}