:root {
  --bg: #11141d;
  --panel: #1a1f2b;
  --panel-strong: #202636;
  --panel-active: #262f44;
  --border: #343b4e;
  --border-strong: #57617c;
  --text: #f2f4fb;
  --muted: #adb5ca;
  --accent: #8f7cff;
  --accent-strong: #a999ff;
  --danger: #ff7b7b;
  --button: #1782c3;
  --button-strong: #2f97d7;
  --shadow: rgba(0, 0, 0, 0.34);
  --shell-width: 100%;
  --page-gutter: 0.55rem;
  --radius: 1rem;
  --radius-small: 0.8rem;
}

html {
  font-size: 36px;
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
}

* {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  min-height: 100%;
}

body {
  min-width: 320px;
  background: linear-gradient(180deg, #11141d 0%, #141926 100%);
  color: var(--text);
  font-family: "Segoe UI", "Trebuchet MS", sans-serif;
  font-size: 1.16rem;
  line-height: 1.4;
  padding-bottom: 10.5rem;
  overflow-x: hidden;
}

a {
  color: inherit;
}

p,
h1,
h2,
h3 {
  margin: 0;
}

ul {
  list-style: none;
  margin: 0;
  padding: 0;
}

button,
input,
audio {
  font: inherit;
}

button,
input,
#drop-zone,
#chapters-list li,
.book-card {
  border-radius: var(--radius);
}

input,
button {
  width: 100%;
  min-height: 6.2rem;
  border: 1px solid var(--border);
}

input {
  padding: 0 1.3rem;
  background: var(--panel-strong);
  color: var(--text);
  font-size: 1.62rem;
  font-weight: 600;
  outline: none;
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.02);
}

input::placeholder {
  color: #8f97aa;
  font-size: 1.62rem;
  font-weight: 500;
}

input:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 0.16rem rgba(143, 124, 255, 0.22);
}

button {
  padding: 1.1rem 1.2rem;
  background: var(--button);
  color: #f8fbff;
  font-weight: 700;
  font-size: 1.45rem;
  letter-spacing: 0.01em;
  cursor: pointer;
  box-shadow: 0 0.35rem 1rem rgba(23, 130, 195, 0.18);
}

button:active {
  transform: translateY(1px);
}

.danger-button {
  background: transparent;
  border-color: #6a4a56;
  color: #ffd6de;
  box-shadow: none;
}

.app-shell {
  width: 100%;
  max-width: none;
  margin: 0 auto;
}

.app-nav {
  position: sticky;
  top: 0;
  z-index: 20;
  display: grid;
  gap: 0.35rem;
  padding: 0.45rem var(--page-gutter);
  background: rgba(17, 20, 29, 0.96);
  border-bottom: 1px solid rgba(87, 97, 124, 0.26);
  backdrop-filter: blur(14px);
}

.app-nav ul {
  display: grid;
  gap: 0.7rem;
}

.app-nav li {
  width: 100%;
}

.nav-title,
.app-nav strong {
  display: inline-flex;
  align-items: center;
  min-height: 2.2rem;
  color: var(--accent-strong);
  font-size: 2.15rem;
  font-weight: 800;
  letter-spacing: -0.02em;
  text-decoration: none;
}

.back-link {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 6.2rem;
  width: 100%;
  padding: 1rem 1.1rem;
  border: 1px solid var(--border);
  background: rgba(255, 255, 255, 0.02);
  color: var(--accent-strong);
  font-weight: 700;
  font-size: 1.45rem;
  text-decoration: none;
}

.app-main {
  padding: 0.3rem var(--page-gutter) 1.35rem;
}

h1,
h2,
h3 {
  line-height: 1.04;
  letter-spacing: -0.04em;
}

h2 {
  font-size: 5rem;
  margin-bottom: 0.25rem;
}

hgroup {
  display: grid;
  gap: 0.22rem;
  margin-bottom: 0.65rem;
}

hgroup p,
.empty-state,
.chapter-num,
#drop-zone,
#now-playing,
body.login-page p,
.error {
  color: var(--muted);
}

body.login-page {
  display: block;
}

body.login-page main {
  width: 100%;
  max-width: none;
  padding: 0.45rem;
}

body.login-page article {
  display: grid;
  gap: 0.7rem;
  width: 100%;
  padding: 1.15rem;
  background: rgba(26, 31, 43, 0.92);
  border: 1px solid var(--border);
  border-radius: 1rem;
  box-shadow: 0 1rem 2.4rem var(--shadow);
}

body.login-page hgroup {
  text-align: center;
}

body.login-page h1 {
  max-width: 100%;
  font-size: 3.85rem;
  line-height: 0.98;
  overflow-wrap: anywhere;
  word-break: break-word;
}

body.login-page hgroup p {
  font-size: 1.72rem;
  line-height: 1.14;
}

.error {
  min-height: 1.4em;
  color: #ffacba;
}

#add-book-form {
  display: grid;
  gap: 1rem;
  margin-bottom: 0.95rem;
}

#books-grid {
  display: grid;
  gap: 1rem;
}

.empty-state {
  padding: 0.35rem 0;
  font-size: 1.28rem;
}

.book-card {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 1rem;
  align-items: start;
  padding: 1.3rem;
  background: linear-gradient(180deg, rgba(32, 38, 54, 0.95) 0%, rgba(26, 31, 43, 0.98) 100%);
  border: 1px solid var(--border);
  box-shadow: 0 0.65rem 1.5rem rgba(0, 0, 0, 0.2);
}

.book-icon {
  font-size: 2.25rem;
  line-height: 1;
}

.book-card h3 {
  align-self: center;
  font-size: 1.8rem;
  word-break: break-word;
}

.book-card button {
  grid-column: 1 / -1;
  margin-top: 0.2rem;
}

#drop-zone {
  display: grid;
  place-items: center;
  min-height: 11rem;
  margin-bottom: 0.75rem;
  padding: 1.25rem;
  background:
    linear-gradient(180deg, rgba(38, 47, 68, 0.35) 0%, rgba(26, 31, 43, 0.75) 100%),
    repeating-linear-gradient(-45deg, rgba(255, 255, 255, 0.025) 0, rgba(255, 255, 255, 0.025) 0.45rem, transparent 0.45rem, transparent 0.9rem);
  border: 2px dashed var(--border-strong);
  text-align: center;
  font-size: 1.65rem;
}

#drop-zone.drag-active,
#drop-zone.uploading {
  color: #efeaff;
  border-color: var(--accent-strong);
  background:
    linear-gradient(180deg, rgba(143, 124, 255, 0.22) 0%, rgba(38, 47, 68, 0.78) 100%),
    repeating-linear-gradient(-45deg, rgba(255, 255, 255, 0.04) 0, rgba(255, 255, 255, 0.04) 0.45rem, transparent 0.45rem, transparent 0.9rem);
}

#chapters-list {
  display: grid;
  gap: 0.45rem;
}

#chapters-list li {
  display: grid;
  grid-template-columns: 3.4rem 1fr;
  gap: 0.8rem;
  align-items: start;
  min-height: 6.8rem;
  padding: 1.15rem 0.95rem;
  background: rgba(26, 31, 43, 0.94);
  border: 1px solid var(--border);
  box-shadow: 0 0.35rem 1rem rgba(0, 0, 0, 0.14);
}

#chapters-list li:active,
#chapters-list li.active {
  background: var(--panel-active);
  border-color: var(--accent-strong);
}

.chapter-num {
  padding-top: 0.08rem;
  font-size: 1.28rem;
  text-align: right;
}

.chapter-name {
  font-size: 1.9rem;
  line-height: 1.08;
  word-break: break-word;
}

#player-bar {
  position: fixed;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 30;
  padding: 0.6rem var(--page-gutter) calc(1rem + env(safe-area-inset-bottom));
  background: rgba(17, 20, 29, 0.97);
  border-top: 1px solid rgba(143, 124, 255, 0.35);
  backdrop-filter: blur(16px);
}

.player-shell {
  display: grid;
  gap: 0.55rem;
}

#now-playing {
  font-size: 1.28rem;
  font-weight: 700;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

#player {
  width: 100%;
  min-height: 4.5rem;
}

body.login-page p,
.error,
hgroup p {
  font-size: 1.28rem;
}