font-size: 20px;
  margin-bottom: 8px;
}
.dash-section-title {
  font-size: 18px;
  margin-bottom: 16px;
}
.dash-shortcuts {
  display: grid;
  gap: 14px;
  grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
}
.dash-shortcut {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 12px;
  box-shadow: 0 4px 12px rgba(17, 31, 48, 0.03);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 12px;
  padding: 20px 16px;
  text-align: center;
  color: var(--ink);
  font-weight: 650;
  font-size: 14px;
  transition: all 0.2s ease;
}
.dash-shortcut:hover {
  border-color: rgba(25, 115, 94, 0.4);
  box-shadow: 0 8px 20px rgba(25, 115, 94, 0.08);
  transform: translateY(-2px);
  color: var(--accent-strong);
}
.dash-shortcut-icon {
  width: 48px;
  height: 48px;
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 24px;
}
.studies-dashboard {
  display: grid;
  gap: 18px;
}
.studies-dashboard-header {
  align-items: flex-start;
}
.studies-dashboard-header p {
  margin: 0;
}
.studies-dashboard-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  justify-content: flex-end;
}
.studies-calendar-layout {
  align-items: start;
  display: grid;
  gap: 18px;
  grid-template-columns: minmax(240px, 320px) minmax(0, 1fr);
}
.studies-recent {
  box-shadow: none;
}
.recent-activity-list {
  display: grid;
  gap: 10px;
}
.recent-activity-item {
  background: var(--panel-soft);
  border-bottom: 1px solid var(--line);
  padding-bottom: 8px;
}
.recent-activity-item strong {
  color: var(--ink);
}
.recent-activity-item span,
.recent-activity-item small {
  color: var(--muted);
}
.calendar-panel {
  box-shadow: none;
}
.calendar-toolbar {
  align-items: center;
  display: grid;
  gap: 12px;
  grid-template-columns: auto 1fr auto;
  margin-bottom: 18px;
}
.calendar-toolbar h2 {
  margin: 0;
  text-align: center;
}
.study-calendar {
  display: grid;
  grid-template-columns: repeat(7, minmax(0, 1fr));
  overflow: hidden;
}
.calendar-weekday {
  background: transparent;
  color: var(--ink);
  font-size: 14px;
  font-weight: 800;
  padding: 0 0 8px;
  text-align: left;
}
.calendar-day {
  align-items: start;
  background: #f3f4f6 !important;
  border: 0 !important;
  border-right: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  border-radius: 0 !important;
  color: #64748b;
  cursor: pointer;
  display: flex;
  flex-direction: column;
  gap: 4px;
  justify-content: flex-start;
  min-height: 150px;
  min-width: 0;
  padding: 0 !important;
  position: relative;
  text-align: left;
  transition: background-color 0.2s;
}
.study-calendar .calendar-day {
  border-right: 1px solid var(--line) !important;
  border-bottom: 1px solid var(--line) !important;
  color: #64748b !important;
}
.calendar-day:hover {
  background: #f8fafc !important;
}
.calendar-day:nth-child(7n) {
  border-right: 0;
}
.calendar-day:disabled {
  opacity: 1;
}
.calendar-day.is-muted {
  background: transparent !important;
  color: #94a3b8 !important;
}
.calendar-day.is-today {
  box-shadow: inset 0 -4px 0 var(--accent) !important;
}
.calendar-day.is-today .calendar-day-number {
  background-color: var(--accent);
  color: white !important;
  border-radius: 50%;
  width: 26px;
  height: 26px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  top: 6px;
  left: 6px;
}
.calendar-day.has-activities {
  background: #eef6f3 !important;
  box-shadow: inset 0 0 0 1px rgba(25, 115, 94, 0.16);
  cursor: pointer;
}
.calendar-day.has-activities:hover {
  background: #e5f1ec !important;
}
.calendar-day-number {
  color: inherit !important;
  font-size: 13px;
  font-weight: 800;
  position: absolute;
  top: 12px;
  left: 12px;
}
.calendar-day-summary,
.calendar-day-time {
  align-self: flex-end;
  color: var(--ink);
  display: inline-flex;
  gap: 5px;
  justify-content: flex-end;
  font-size: 13px;
  font-weight: 700;
  margin-right: 12px;
  text-align: right;
}
.calendar-day-summary {
  margin-top: 52px;
}
.calendar-footer {
  display: flex;
  justify-content: center;
  margin-top: 16px;
}
.day-activity-summary {
  align-items: center;
  background: var(--panel-soft);
  border: 1px solid var(--line);
  border-radius: 8px;
  display: flex;
  justify-content: space-between;
  margin-bottom: 12px;
  padding: 12px;
}
.day-activity-list {
  display: grid;
  gap: 10px;
}
.day-activity-item {
  align-items: center;
  border: 1px solid var(--line);
  border-radius: 8px;
  color: inherit;
  display: flex;
  gap: 12px;
  justify-content: space-between;
  padding: 12px;
  text-decoration: none;
}
.day-activity-item:hover {
  color: inherit;
  border-color: rgba(25, 115, 94, 0.3);
  box-shadow: 0 0 0 1px rgba(25, 115, 94, 0.08);
}
.day-activity-item div {
  display: grid;
  gap: 4px;
}
.day-activity-item span,
.day-activity-item small {
  color: var(--muted);
}
.materia-color-preview {
  background: var(--materia-color);
  border: 1px solid rgba(15, 23, 42, 0.12);
  border-radius: 999px;
  display: inline-block;
  height: 16px;
  margin-right: 8px;
  vertical-align: -3px;
  width: 16px;
}
.study-color-field {
  align-items: center;
  display: flex;
  gap: 12px;
}
.study-time-page {
  display: grid;
  gap: 18px;
}
.study-time-header {
  align-items: center;
  display: flex;
  gap: 16px;
  justify-content: space-between;
}
.study-time-header h1,
.study-time-navigation h2 {
  margin: 0;
}
.study-time-header p {
  color: var(--muted);
  margin: 6px 0 0;
}
.study-time-filters {
  display: grid;
  gap: 18px;
}
.study-time-chart-tabs {
  align-items: end;
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}
.study-time-chart-tab {
  align-items: center;
  background: #f1f5f9;
  border: 1px solid transparent;
  border-radius: 8px 8px 0 0;
  color: #334155;
  display: inline-flex;
  font-weight: 800;
  gap: 8px;
  padding: 12px 18px;
  text-decoration: none;
  text-transform: uppercase;
}
.study-time-chart-tab.is-active {
  background: #fff;
  border-color: rgba(15, 23, 42, 0.08);
  box-shadow: 0 -4px 16px rgba(15, 23, 42, 0.06);
}
.study-time-mode {
  display: flex;
  flex-wrap: wrap;
  gap: 28px;
}
.study-time-radio {
  align-items: flex-start;
  display: inline-flex;
  gap: 8px;
  max-width: 280px;
}
.study-time-radio input {
  margin-top: 4px;
}
.study-time-radio strong,
.study-time-radio small {
  display: block;
}
.study-time-radio small {
  color: var(--muted);
  font-size: 12px;
}
.study-time-content-filter {
  max-width: 360px;
}
.study-time-periods {
  display: grid;
  gap: 8px;
  grid-template-columns: repeat(6, minmax(92px, 1fr));
}
.study-time-periods .btn {
  font-weight: 700;
}
.study-time-custom {
  align-items: end;
  display: grid;
  gap: 12px;
  grid-template-columns: repeat(2, minmax(180px, 1fr)) auto;
}
.study-time-panel {
  display: grid;
  gap: 24px;
}
.study-time-navigation {
  align-items: center;
  display: grid;
  grid-template-columns: 64px 1fr 64px;
  text-align: center;
}
.study-time-arrow {
  align-items: center;
  background: #f8fafc;
  border: 1px solid rgba(15, 23, 42, 0.08);
  border-radius: 999px;
  box-shadow: 0 10px 22px rgba(15, 23, 42, 0.12);
  color: #475569;
  display: inline-flex;
  font-size: 44px;
  height: 56px;
  justify-content: center;
  line-height: 1;
  text-decoration: none;
  width: 56px;
}
.study-time-chart-layout {
  align-items: center;
  display: grid;
  gap: 34px;
  grid-template-columns: minmax(280px, 1.1fr) minmax(280px, 0.9fr);
}
.study-time-chart-wrap {
  display: grid;
  justify-items: center;
}
.study-time-pie,
.study-time-empty-state {
  aspect-ratio: 1;
  border-radius: 50%;
  width: min(430px, 100%);
}
.study-time-pie {
  background: conic-gradient(var(--study-time-pie));
  box-shadow: 0 12px 24px rgba(15, 23, 42, 0.22);
}
.study-time-bars {
  display: grid;
  gap: 12px;
  grid-template-columns: 54px minmax(0, 1fr);
  width: 100%;
}
.study-time-axis {
  color: #64748b;
  display: flex;
  flex-direction: column;
  font-size: 12px;
  font-weight: 700;
  height: 340px;
  justify-content: space-between;
  text-align: right;
}
.study-time-bars-plot {
  align-items: end;
  border-bottom: 1px solid rgba(15, 23, 42, 0.16);
  display: flex;
  gap: clamp(6px, 1.1vw, 14px);
  min-height: 340px;
  overflow-x: auto;
  padding: 0 8px;
}
.study-time-bar-column {
  align-items: center;
  display: grid;
  gap: 8px;
  min-width: 34px;
}
.study-time-bar-stack {
  align-items: end;
  display: flex;
  flex-direction: column-reverse;
  height: 300px;
  justify-content: flex-start;
  width: clamp(22px, 3vw, 42px);
}
.study-time-bar-segment {
  background: var(--study-time-color);
  display: block;
  min-height: 2px;
  width: 100%;
  height: var(--study-time-height);
}
.study-time-bar-segment:first-child {
  border-radius: 0 0 3px 3px;
}
.study-time-bar-segment:last-child {
  border-radius: 3px 3px 0 0;
}
.study-time-bar-label {
  color: #64748b;
  font-size: 11px;
  font-weight: 700;
  min-height: 28px;
  text-align: center;
  white-space: nowrap;
}
.study-time-empty-state {
  align-items: center;
  background: #f1f5f9;
  color: var(--muted);
  display: flex;
  flex-direction: column;
  gap: 16px;
  font-weight: 700;
  justify-content: center;
  padding: 36px;
  text-align: center;
}
.study-time-empty-state strong {
  color: #334155;
  font-size: clamp(18px, 2vw, 24px);
  max-width: 300px;
}
.study-time-summary {
  display: grid;
  gap: 10px;
}
.study-time-total {
  color: #334155;
  font-size: clamp(34px, 5vw, 54px);
  line-height: 1;
}
.study-time-summary > span {
  color: #475569;
}
.study-time-legend {
  display: grid;
  list-style: none;
  margin: 18px 0 0;
  padding: 0;
}
.study-time-legend li {
  align-items: center;
  border-bottom: 1px solid rgba(15, 23, 42, 0.1);
  display: grid;
  gap: 10px;
  grid-template-columns: 16px minmax(0, 1fr) auto;
  padding: 11px 0;
}
.study-time-dot {
  background: var(--study-time-color);
  border-radius: 999px;
  height: 14px;
  width: 14px;
}
.study-time-name {
  overflow-wrap: anywhere;
}
.study-time-legend strong {
  color: #475569;
  white-space: nowrap;
}
.app-body:has(.study-bottom-bar) .app-main:not(.app-main-clock) {
  padding-bottom: 96px;
}
.study-bottom-bar {
  align-items: center;
  background: rgba(15, 23, 42, 0.85);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: 100px;
  bottom: 24px;
  box-shadow: 0 10px 40px -10px rgba(0, 0, 0, 0.3);
  color: #fff;
  display: flex;
  gap: 8px;
  left: 50%;
  transform: translateX(-50%);
  min-height: 54px;
  padding: 10px 20px;
  position: fixed;
  width: max-content;
  max-width: 95%;
  z-index: 40;
  transition: all 0.3s ease;
}
.study-bottom-inner {
  align-items: center;
  display: flex;
  flex-wrap: nowrap;
  justify-content: center;
  gap: 16px;
  margin: 0 auto;
  min-width: 0;
  overflow-x: auto;
  -ms-overflow-style: none;  /* IE and Edge */
  scrollbar-width: none;  /* Firefox */
}
.study-bottom-inner::-webkit-scrollbar {
  display: none; /* Chrome, Safari and Opera */
}
.study-bottom-minimize {
  align-items: center;
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid transparent;
  border-radius: 50%;
  color: rgba(255, 255, 255, 0.7);
  cursor: pointer;
  display: inline-flex;
  flex: 0 0 auto;
  height: 30px;
  justify-content: center;
  min-height: 30px;
  padding: 0;
  transition: all 0.2s ease;
  width: 30px;
}
.study-bottom-minimize:hover {
  background: rgba(255, 255, 255, 0.16);
  color: #fff;
}
.study-fab {
  align-items: center;
  background: rgba(15, 23, 42, 0.85);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: 50%;
  bottom: 24px;
  box-shadow: 0 10px 40px -10px rgba(0, 0, 0, 0.3);
  color: #fff;
  cursor: pointer;
  display: none;
  flex-direction: column;
  gap: 0;
  height: 56px;
  justify-content: center;
  line-height: 1;
  position: fixed;
  right: 24px;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
  width: 56px;
  z-index: 41;
}
.study-fab:hover {
  transform: scale(1.06);
}
.study-fab-icon {
  font-size: 20px;
}
.study-fab-time {
  font-family: 'JetBrains Mono', 'Courier New', monospace;
  font-size: 10px;
  font-variant-numeric: tabular-nums;
  font-weight: 700;
  letter-spacing: 0.3px;
  margin-top: 2px;
}
.study-fab .study-fab-icon {
  font-size: 24px;
}
.study-fab:has(.study-fab-time) .study-fab-icon {
  font-size: 18px;
}
.study-fab-pulse {
  background: #10b981;
  border-radius: 50%;
  box-shadow: 0 0 0 0 rgba(16, 185, 129, 0.6);
  height: 9px;
  position: absolute;
  right: 9px;
  top: 9px;
  width: 9px;
  animation: studyFabPulse 1.8s infinite;
}
.study-fab-pulse-paused {
  animation: none;
  background: #f59e0b;
  box-shadow: none;
}
@keyframes studyFabPulse {
  0% { box-shadow: 0 0 0 0 rgba(16, 185, 129, 0.6); }
  70% { box-shadow: 0 0 0 8px rgba(16, 185, 129, 0); }
  100% { box-shadow: 0 0 0 0 rgba(16, 185, 129, 0); }
}
body.study-minimized .study-bottom-bar {
  display: none;
}
body.study-minimized .study-fab {
  display: inline-flex;
}
.app-body.study-minimized:has(.study-bottom-bar) .app-main:not(.app-main-clock) {
  padding-bottom: 24px;
}
.study-bottom-bar select {
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.15);
  border-radius: 100px;
  color: #f8fafc;
  font-size: 14px;
  font-weight: 500;
  min-height: 36px;
  padding: 4px 34px 4px 16px;
  outline: none;
  transition: all 0.2s;
  cursor: pointer;
  max-width: 180px;
  text-overflow: ellipsis;
  white-space: nowrap;
}
.study-bottom-bar select:hover,
.study-bottom-bar select:focus {
  border-color: rgba(255, 255, 255, 0.3);
  background: rgba(255, 255, 255, 0.1);
}
.study-bottom-bar select option {
  background: #1e293b;
  color: #fff;
}
.study-bottom-button {
  align-items: center;
  background: rgba(255, 255, 255, 0.1);
  border: 1px solid transparent;
  border-radius: 100px;
  color: #fff;
  cursor: pointer;
  display: inline-flex;
  font-size: 14px;
  font-weight: 600;
  justify-content: center;
  min-height: 36px;
  padding: 6px 18px;
  text-decoration: none;
  white-space: nowrap;
  transition: all 0.2s ease;
}
.study-bottom-button:hover {
  background: rgba(255, 255, 255, 0.2);
  color: #fff;
}
.study-bottom-button-primary {
  background: #10b981;
  color: #fff;
}
.study-bottom-button-primary:hover {
  background: #059669;
}
.study-bottom-message {
  color: #94a3b8;
  font-weight: 500;
  font-size: 14px;
}
.study-bottom-subject {
  color: #f8fafc;
  font-size: 15px;
  font-weight: 700;
  display: inline-flex;
  align-items: baseline;
  gap: 6px;
  overflow: hidden;
  white-space: nowrap;
  max-width: 300px;
  text-decoration: none;
  transition: opacity 0.2s ease;
}
a.study-bottom-subject:hover {
  color: #f8fafc;
  opacity: 0.8;
}
.study-bottom-subject-name,
.study-bottom-content-name {
  min-width: 0;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}
.study-bottom-subject-name {
  flex: 0 1 auto;
}
.study-bottom-content-name {
  color: rgba(248, 250, 252, 0.55);
  flex: 1 1 auto;
  font-size: 13px;
  font-weight: 400;
}
.study-bottom-timer {
  color: #fff;
  font-family: 'JetBrains Mono', 'Courier New', monospace;
  font-size: 18px;
  font-variant-numeric: tabular-nums;
  font-weight: 700;
  min-width: 86px;
  text-align: center;
  letter-spacing: 0.5px;
}
.study-bottom-timer-label {
  font-size: 11px;
  font-weight: 500;
  opacity: 0.5;
  margin: 0 3px 0 1px;
  letter-spacing: 0;
}
.study-bottom-inline {
  display: inline-flex;
  margin: 0;
}
.study-bottom-icon {
  display: none;
}

.activity-fieldset {
  border: 0;
  margin: 0;
  padding: 0;
}

.activity-rating {
  align-items: center;
  display: inline-flex !important;
  flex-direction: row !important;
  flex-wrap: wrap;
  gap: 4px 10px;
  justify-content: flex-start;
}

.activity-rating button.activity-rating-star {
  background: transparent !important;
  border: 0 !important;
  border-radius: 0 !important;
  box-shadow: none !important;
  color: #cbd5e1 !important;
  cursor: pointer;
  display: inline-flex;
  font-size: 26px;
  font-weight: 400;
  height: 30px;
  justify-content: center;
  line-height: 1;
  min-height: 0;
  min-width: 0;
  padding: 0 1px !important;
  width: 28px;
}

.activity-rating .btn.activity-rating-star:focus,
.activity-rating .btn.activity-rating-star:active {
  background: transparent !important;
  border: 0 !important;
  box-shadow: none !important;
  outline: 0;
}

.activity-rating button.activity-rating-star.is-active,
.activity-rating button.activity-rating-star:hover {
  color: #f59e0b !important;
}

textarea.activity-notes {
  min-height: 38px;
  resize: vertical;
}
.session-panel {
  display: grid;
  gap: 14px;
}
.session-panel .study-real-end {
  align-items: end;
  display: grid;
  gap: 12px;
  grid-template-columns: minmax(220px, 320px) auto;
}
.session-timer {
  color: var(--ink);
  font-size: clamp(48px, 10vw, 92px);
  font-variant-numeric: tabular-nums;
  font-weight: 850;
  letter-spacing: 0;
  line-height: 1;
}
.study-clock-screen {
  background:
    linear-gradient(rgba(255, 255, 255, 0.035) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.035) 1px, transparent 1px),
    radial-gradient(circle at 50% 18%, rgba(16, 185, 129, 0.1), transparent 28rem),
    #111315;
  background-size: 48px 48px, 48px 48px, auto, auto;
  color: #f8fafc;
  min-height: 100vh;
  overflow: hidden;
  padding: clamp(24px, 5vw, 56px);
  position: relative;
  width: 100%;
}
.study-clock-screen.has-custom-clock-bg {
  background:
    linear-gradient(rgba(8, 14, 20, 0.62), rgba(8, 14, 20, 0.62)),
    var(--clock-bg-image) center / cover no-repeat;
}
.study-clock-shell {
  align-items: center;
  display: grid;
  gap: clamp(22px, 4vw, 38px);
  justify-items: center;
  position: absolute;
  top: 40%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: 100%;
  padding: 0 clamp(24px, 5vw, 56px);
  max-width: calc(1180px + clamp(24px, 5vw, 56px) * 2);
}
.study-clock-date {
  color: rgba(248, 250, 252, 0.54);
  font-size: clamp(15px, 2vw, 19px);
  font-weight: 600;
  text-align: center;
}
.study-clock-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 32px;
  width: min(860px, 100%);
  justify-content: flex-start;
}
.study-clock-meta div {
  text-align: left;
}
.study-clock-meta span {
  color: rgba(248, 250, 252, 0.4);
  display: flex;
  justify-content: flex-start;
  align-items: center;
  gap: 6px;
  font-size: 10px;
  font-weight: 700;
  letter-spacing: 0.08em;
  margin-bottom: 4px;
  text-transform: uppercase;
}
.study-clock-meta strong {
  color: #54c2a2;
  display: block;
  font-size: 15px;
  font-weight: 600;
  opacity: 0.85;
  overflow-wrap: anywhere;
}
.flip-clock {
  align-items: center;
  display: flex;
  gap: clamp(8px, 1.6vw, 18px);
  justify-content: center;
  width: 100%;
}
.flip-unit {
  display: flex;
  gap: clamp(6px, 1vw, 12px);
}
.flip-card {
  aspect-ratio: 0.72;
  border-radius: 8px;
  box-shadow: 0 18px 38px rgba(0, 0, 0, 0.34);
  display: inline-block;
  min-width: clamp(68px, 13vw, 190px);
  position: relative;
  perspective: 600px;
  overflow: visible;
  background: transparent;
  border: none;
}
.flip-panel {
  position: absolute;
  left: 0;
  right: 0;
  width: 100%;
  height: 50%;
  overflow: hidden;
  backface-visibility: hidden;
}
.flip-panel-top {
  top: 0;
  border-top-left-radius: 8px;
  border-top-right-radius: 8px;
  background: linear-gradient(180deg, #2c2c30 0%, #1e1e22 100%);
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-bottom: 1px solid rgba(0, 0, 0, 0.78);
  box-shadow: inset 0 -1px 0 rgba(255, 255, 255, 0.035);
}
.flip-panel-bottom {
  bottom: 0;
  border-bottom-left-radius: 8px;
  border-bottom-right-radius: 8px;
  background: linear-gradient(180deg, #1c1c1f 0%, #111113 100%);
  border: 1px solid rgba(255, 255, 255, 0.03);
  border-top: 1px solid rgba(0, 0, 0, 0.88);
  box-shadow:
    inset 0 1px 0 rgba(255, 255, 255, 0.035),
    inset 0 -2px 8px rgba(0, 0, 0, 0.6);
}
.flip-card-number {
  position: absolute;
  left: 0;
  right: 0;
  width: 100%;
  height: 200%;
  display: flex;
  justify-content: center;
  align-items: center;
  font-family: "Arial Black", Impact, Inter, system-ui, sans-serif;
  font-size: clamp(74px, 14vw, 210px);
  font-variant-numeric: tabular-nums;
  font-weight: 900;
  color: #fff;
  line-height: 1;
  text-shadow: 0 2px 4px rgba(0, 0, 0, 0.5), 0 1px 0 rgba(16, 185, 129, 0.15);
}
.flip-panel-top .flip-card-number {
  top: 0;
}
.flip-panel-bottom .flip-card-number {
  bottom: 0;
}
.flip-card-animated {
  position: absolute;
  left: 0;
  top: 0;
  width: 100%;
  height: 50%;
  transform-origin: bottom center;
  transform-style: preserve-3d;
  z-index: 3;
  transform: rotateX(0deg);
  pointer-events: none;
}
.flip-card.is-flipping .flip-card-animated {
  animation: flipCardAnim 0.55s cubic-bezier(0.25, 1, 0.5, 1) forwards;
}
.flip-card.is-resetting .flip-card-animated {
  visibility: hidden;
}
.flip-animated-front,
.flip-animated-back {
  position: absolute;
  left: 0;
  top: 0;
  width: 100%;
  height: 100%;
  overflow: hidden;
  backface-visibility: hidden;
}
.flip-animated-front {
  background: linear-gradient(180deg, #2c2c30 0%, #1e1e22 100%);
  border-top-left-radius: 8px;
  border-top-right-radius: 8px;
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-bottom: 1px solid rgba(0, 0, 0, 0.78);
  box-shadow: inset 0 -1px 0 rgba(255, 255, 255, 0.035);
}
.flip-animated-back {
  background: linear-gradient(180deg, #1c1c1f 0%, #111113 100%);
  border-bottom-left-radius: 8px;
  border-bottom-right-radius: 8px;
  border: 1px solid rgba(255, 255, 255, 0.03);
  border-top: 1px solid rgba(0, 0, 0, 0.88);
  box-shadow:
    inset 0 1px 0 rgba(255, 255, 255, 0.035),
    inset 0 -2px 8px rgba(0, 0, 0, 0.6);
  transform: rotateX(180deg);
}
.flip-animated-front .flip-card-number {
  top: 0;
}
.flip-animated-back .flip-card-number {
  bottom: 0;
}
.flip-separator {
  color: rgba(255, 255, 255, 0.42);
  font-family: Inter, system-ui, sans-serif;
  font-size: clamp(36px, 6vw, 90px);
  font-weight: 300;
  line-height: 1;
  transform: translateY(-8%);
}
.study-clock-actions,
.study-clock-empty {
  align-items: center;
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  justify-content: center;
}
.study-clock-empty p {
  color: rgba(248, 250, 252, 0.7);
  margin: 0;
  width: 100%;
  text-align: center;
}
.study-clock-start {
  align-items: end;
  display: grid;
  gap: 14px;
  grid-template-columns: minmax(220px, 1fr) minmax(220px, 1fr) auto;
  width: min(860px, 100%);
  margin-top: clamp(40px, 10vh, 120px);
}
.study-clock-start label {
  color: rgba(248, 250, 252, 0.82);
}
.study-clock-start select {
  background: rgba(255, 255, 255, 0.94);
}
@keyframes flipCardAnim {
  0% { transform: rotateX(0deg); }
  100% { transform: rotateX(-180deg); }
}