:root {
  --bg:
    radial-gradient(120% 75% at 50% 12%, rgba(209, 224, 236, 0.86) 0%, rgba(209, 224, 236, 0) 64%),
    linear-gradient(180deg, #d9dced 0%, #d8e1ec 42%, #e5e4f0 100%);
  --text: #111532;
  --muted: #6a6f95;
  --primary: #636bff;
  --primary-dark: #404dff;
  --card-light: rgba(255, 255, 255, 0.75);
  --panel-dark: #080b26;
  font-family: 'Pretendard', 'Inter', system-ui, -apple-system, BlinkMacSystemFont,
    'Segoe UI', sans-serif;
}

* {
  box-sizing: border-box;
}

[hidden] {
  display: none !important;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  min-height: 100vh;
  background: var(--bg);
  color: var(--text);
  padding: clamp(0.75rem, 2vw, 2rem);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
}

img {
  max-width: 100%;
  display: block;
}

a {
  color: inherit;
  text-decoration: none;
}

.split {
  margin: clamp(0.5rem, 2vw, 1.2rem) auto;
  width: min(1040px, 88vw);
  min-height: min(720px, calc(100vh - 220px));
  display: grid;
  grid-template-columns: 3fr 2fr;
  gap: 2rem;
  align-items: stretch;
}

.intro-panel,
.register-panel {
  border-radius: 32px;
  padding: clamp(1.2rem, 3.5vw, 2.4rem);
  height: 100%;
}

.intro-panel {
  background: linear-gradient(150deg, rgba(255, 255, 255, 0.85), rgba(236, 239, 255, 0.95));
  box-shadow: 0 20px 45px rgba(70, 78, 133, 0.18);
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

.intro-panel h1 {
  margin: 0.3rem 0 0.8rem;
  font-size: clamp(1.9rem, 3.8vw, 2.8rem);
}

.lead {
  font-size: 1rem;
  color: #2f3362;
}

.eyebrow {
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--muted);
}

.session-details {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
  gap: 1rem;
  margin: 1.5rem 0 0.5rem;
}

.session-details .label {
  margin: 0;
  font-size: 0.8rem;
  color: #8e92ba;
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

.session-details .value {
  margin: 0.3rem 0 0;
  font-weight: 600;
  font-size: 1.05rem;
}

.agenda-list {
  list-style: none;
  padding: 0;
  margin: 0.8rem 0 0;
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.agenda-list li {
  padding: 0.5rem 1rem;
  border-radius: 999px;
  background: rgba(99, 107, 255, 0.12);
  color: #363c7a;
  font-weight: 600;
}

.copy-error {
  margin: 0 0 1rem;
  padding: 0.65rem 1rem;
  border-radius: 16px;
  background: #fff5d9;
  color: #8a5200;
  font-size: 0.9rem;
  font-weight: 600;
}

.intro-tiles {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 1rem;
}

.intro-tiles article {
  background: var(--card-light);
  border-radius: 24px;
  padding: 1.4rem;
  box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.4);
}

.intro-tiles h3 {
  margin: 0 0 0.6rem;
}

.register-panel {
  background: transparent;
  padding: 0;
  display: flex;
  align-items: stretch;
  justify-content: center;
}

.register-card {
  background: #0d123f;
  border: 1px solid rgba(255, 255, 255, 0.12);
  border-radius: 28px;
  padding: clamp(1.2rem, 3vw, 2.2rem);
  color: #f5f6ff;
  width: min(420px, 100%);
  box-shadow: 0 18px 45px rgba(4, 6, 21, 0.28);
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

.register-card h2 {
  margin: 0.2rem 0 0.6rem;
  font-size: 1.9rem;
}

.card-lead {
  margin: 0 0 1rem;
  color: rgba(255, 255, 255, 0.7);
}

.register-form {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  margin-bottom: 0.5rem;
}

.field {
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
}

label {
  font-weight: 600;
  font-size: 0.9rem;
  color: rgba(255, 255, 255, 0.75);
}

input,
textarea {
  width: 100%;
  border-radius: 14px;
  border: 1px solid rgba(255, 255, 255, 0.15);
  background: rgba(255, 255, 255, 0.06);
  padding: 0.75rem 0.95rem;
  color: #fff;
  font-size: 0.95rem;
  font-family: inherit;
}

textarea {
  resize: vertical;
  min-height: 60px;
}

.primary {
  border: none;
  border-radius: 999px;
  padding: 0.85rem 1.6rem;
  font-weight: 600;
  background: linear-gradient(90deg, var(--primary), var(--primary-dark));
  color: white;
  cursor: pointer;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.primary:hover {
  transform: translateY(-1px);
  box-shadow: 0 15px 35px rgba(74, 85, 255, 0.35);
}

.secondary {
  border: 1px solid rgba(255, 255, 255, 0.25);
  border-radius: 16px;
  padding: 0.85rem 1.5rem;
  background: transparent;
  color: #f1f2ff;
  font-weight: 600;
  cursor: pointer;
  transition: border-color 0.2s ease, color 0.2s ease;
}

.secondary:hover {
  border-color: rgba(255, 255, 255, 0.45);
  color: white;
}

.form-status {
  min-height: 1.2rem;
  color: #9bf3c0;
  margin: 0.3rem 0 0;
}

.progress-card {
  margin-top: 0.3rem;
  padding: 0.7rem 0.8rem;
  border-radius: 16px;
  border: 1px solid rgba(255, 255, 255, 0.14);
  background: rgba(255, 255, 255, 0.06);
}

.progress-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: grid;
  gap: 0.35rem;
}

.progress-item {
  display: grid;
  grid-template-columns: 16px 1fr auto;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.82rem;
  color: rgba(255, 255, 255, 0.74);
}

.progress-icon {
  width: 14px;
  height: 14px;
  border-radius: 999px;
  border: 2px solid rgba(255, 255, 255, 0.35);
  position: relative;
}

.progress-state {
  font-size: 0.75rem;
  color: rgba(255, 255, 255, 0.58);
}

.progress-item.is-active .progress-icon {
  border-color: #8ea4ff;
  border-top-color: transparent;
  animation: progressSpin 0.9s linear infinite;
}

.progress-item.is-active .progress-state {
  color: #c8d5ff;
}

.progress-item.is-success .progress-icon {
  background: rgba(144, 243, 178, 0.22);
  border-color: #90f3b2;
}

.progress-item.is-success .progress-icon::after {
  content: '';
  position: absolute;
  left: 3px;
  top: 0px;
  width: 4px;
  height: 8px;
  border-right: 2px solid #90f3b2;
  border-bottom: 2px solid #90f3b2;
  transform: rotate(45deg);
}

.progress-item.is-success .progress-state {
  color: #90f3b2;
}

.progress-item.is-error .progress-icon {
  background: rgba(255, 146, 146, 0.2);
  border-color: #ff9c9c;
}

.progress-item.is-error .progress-icon::before,
.progress-item.is-error .progress-icon::after {
  content: '';
  position: absolute;
  left: 5px;
  top: 1px;
  width: 2px;
  height: 8px;
  background: #ff9c9c;
}

.progress-item.is-error .progress-icon::before {
  transform: rotate(45deg);
}

.progress-item.is-error .progress-icon::after {
  transform: rotate(-45deg);
}

.progress-item.is-error .progress-state {
  color: #ffbfbf;
}

@keyframes progressSpin {
  from {
    transform: rotate(0deg);
  }
  to {
    transform: rotate(360deg);
  }
}

.form-error {
  margin: 0.2rem 0 0;
  color: #ffbfbf;
  font-size: 0.9rem;
}

.form-status.form-error,
.cancel-status.form-error {
  color: #ffbfbf;
}

.footer {
  text-align: center;
  color: var(--muted);
  margin-top: 0.5rem;
  font-size: 0.9rem;
}

.footer-logos {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 1rem;
  margin-bottom: 0.5rem;
}

.footer-logos img {
  height: 26px;
  width: auto;
  max-width: 140px;
  object-fit: contain;
  flex: 0 0 auto;
  filter: drop-shadow(0 4px 12px rgba(0, 0, 0, 0.2));
}

.footer-link {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.4rem;
  padding: 0.35rem 1rem;
  border-radius: 999px;
  font-size: 0.85rem;
  background: rgba(99, 107, 255, 0.12);
  color: #363c7a;
  font-weight: 600;
}

.footer-actions {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
}

.inline-link {
  display: inline-block;
  margin-top: 0.5rem;
}

.cancel-page {
  width: min(520px, 100%);
  margin: 0 auto;
}

.cancel-panel {
  background: rgba(255, 255, 255, 0.9);
  border-radius: 32px;
  padding: clamp(1.5rem, 4vw, 3rem);
  box-shadow: 0 25px 60px rgba(78, 84, 130, 0.25);
}

.cancel-panel label {
  color: #333a66;
}

.cancel-panel input {
  background: rgba(17, 21, 50, 0.04);
  border: 1px solid rgba(17, 21, 50, 0.08);
  color: #111532;
}

.cancel-panel .primary {
  background: linear-gradient(90deg, var(--primary), var(--primary-dark));
  color: #fff;
}

.cancel-form .primary {
  margin-top: 0.5rem;
}

.cancel-panel h1 {
  margin: 0.3rem 0 0.5rem;
}

.cancel-panel p {
  color: var(--muted);
  margin-bottom: 1.5rem;
}

#cancel-page-status {
  color: var(--text);
  font-weight: 600;
}

.admin-page {
  width: min(960px, 100%);
  margin: 0 auto;
}

.admin-panel {
  background: rgba(255, 255, 255, 0.92);
  border-radius: 32px;
  padding: clamp(1.2rem, 3.6vw, 2.4rem);
  box-shadow: 0 25px 60px rgba(78, 84, 130, 0.25);
}

.admin-panel label {
  color: #333a66;
}

.admin-panel input {
  background: rgba(17, 21, 50, 0.04);
  border: 1px solid rgba(17, 21, 50, 0.08);
  color: #111532;
}

.admin-auth {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 0.7rem;
  align-items: end;
  margin: 1rem 0 1.2rem;
}

.admin-status {
  margin: 0.4rem 0 1rem;
  min-height: 1.2rem;
  color: #303763;
  font-weight: 600;
}

.admin-table-wrap {
  overflow-x: auto;
}

.admin-table {
  width: 100%;
  border-collapse: collapse;
  min-width: 760px;
}

.admin-table th,
.admin-table td {
  text-align: left;
  padding: 0.7rem 0.55rem;
  border-bottom: 1px solid rgba(17, 21, 50, 0.1);
  font-size: 0.9rem;
  color: #23284f;
  vertical-align: top;
}

.admin-table th {
  font-size: 0.8rem;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: #6670a6;
}

.admin-delete {
  border: 1px solid rgba(214, 54, 54, 0.25);
  background: rgba(214, 54, 54, 0.08);
  color: #a83535;
  border-radius: 999px;
  padding: 0.36rem 0.75rem;
  font-size: 0.82rem;
  font-weight: 700;
  line-height: 1;
  white-space: nowrap;
  min-width: 46px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
}

@media (max-width: 900px) {
  body {
    padding: 1rem;
    justify-content: flex-start;
  }

  .split {
    grid-template-columns: 1fr;
    min-height: auto;
  }

  .intro-panel,
  .register-panel {
    padding: 2rem;
    height: auto;
  }
}

.tile-loop {
  position: relative;
  overflow: hidden;
  color: #0f1533;
  background: linear-gradient(145deg, rgba(255, 255, 255, 0.98), rgba(245, 246, 255, 0.95));
  border: 1px solid rgba(116, 124, 201, 0.18);
  box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.7), 0 20px 35px rgba(76, 83, 132, 0.18);
}

.tile-loop::before,
.tile-loop::after {
  content: '';
  position: absolute;
  inset: -30%;
  background: linear-gradient(140deg, rgba(110, 138, 255, 0.25), transparent 60%),
    radial-gradient(circle at 70% 30%, rgba(255, 197, 255, 0.25), transparent 65%);
  opacity: 0.65;
  mix-blend-mode: multiply;
  animation: loopShift 18s linear infinite;
}

.tile-loop::after {
  animation-delay: -9s;
  transform: rotate(30deg);
  opacity: 0.4;
}

.tile-loop h3,
.tile-loop p {
  position: relative;
  color: inherit;
}

@keyframes loopShift {
  0% {
    transform: translate(-12%, -8%) scale(1);
    opacity: 0.4;
  }
  50% {
    transform: translate(10%, 8%) scale(1.05);
    opacity: 0.75;
  }
  100% {
    transform: translate(-10%, 6%) scale(1);
    opacity: 0.4;
  }
}

body[data-page='admin'] {
  justify-content: flex-start;
  align-items: stretch;
  padding: clamp(0.8rem, 2vw, 1.5rem);
}

body[data-page='admin'] .admin-page {
  width: min(1240px, 100%);
  margin: 0 auto;
}

.admin-login-card {
  background: rgba(255, 255, 255, 0.92);
  border-radius: 32px;
  padding: clamp(1.2rem, 3.6vw, 2.4rem);
  box-shadow: 0 25px 60px rgba(78, 84, 130, 0.25);
  max-width: 860px;
  margin: clamp(1rem, 6vh, 3.6rem) auto 0;
}

.admin-login-card label,
.admin-content label {
  color: #333a66;
}

.admin-login-card input,
.admin-content input,
.admin-content select {
  background: #ffffff;
  border: 1px solid rgba(72, 84, 172, 0.3);
  color: #111532;
  box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.9);
}

.admin-login-card input::placeholder,
.admin-content input::placeholder {
  color: #8f97c2;
}

.admin-login-card input:focus,
.admin-content input:focus,
.admin-content select:focus {
  outline: none;
  border-color: rgba(80, 92, 197, 0.8);
  box-shadow: 0 0 0 3px rgba(92, 106, 230, 0.2);
}

.admin-dashboard {
  display: grid;
  grid-template-columns: 220px 1fr;
  gap: 1rem;
  margin-top: 1rem;
  min-height: calc(100vh - 2.8rem);
}

.admin-sidebar {
  background: rgba(13, 18, 63, 0.94);
  border-radius: 24px;
  padding: 1.1rem;
  color: #f2f3ff;
  box-shadow: 0 20px 45px rgba(25, 32, 92, 0.3);
}

.admin-sidebar .eyebrow {
  color: rgba(210, 215, 255, 0.75);
}

.admin-sidebar h2 {
  margin: 0.3rem 0 1rem;
  font-size: 1.3rem;
}

.admin-sidebar-menu {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.sidebar-menu-btn {
  border: 0;
  border-radius: 12px;
  background: rgba(255, 255, 255, 0.08);
  color: #d8ddff;
  padding: 0.68rem 0.75rem;
  text-align: left;
  font-weight: 600;
  cursor: pointer;
}

.sidebar-menu-btn.is-active {
  background: linear-gradient(90deg, #7278ff, #505af5);
  color: #fff;
}

.admin-content {
  background: rgba(255, 255, 255, 0.92);
  border-radius: 24px;
  padding: 1rem;
  box-shadow: 0 25px 60px rgba(78, 84, 130, 0.25);
}

.admin-toolbar {
  display: flex;
  justify-content: space-between;
  gap: 0.8rem;
  align-items: flex-start;
  margin-bottom: 0.9rem;
}

.admin-toolbar h3 {
  margin: 0;
  font-size: 1.25rem;
}

.admin-dashboard-status {
  margin: 0.3rem 0 0;
  color: #303763;
  font-weight: 600;
  min-height: 1.1rem;
}

.admin-toolbar-actions {
  display: flex;
  gap: 0.5rem;
}

.admin-btn-secondary {
  color: #2c356f;
  border-color: rgba(44, 53, 111, 0.24);
}

.admin-view {
  display: none;
}

.admin-view.is-active {
  display: block;
}

.admin-stats-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 0.7rem;
  margin-bottom: 0.8rem;
}

.admin-stats-grid-after-chart {
  margin-top: 0.7rem;
}

.admin-stat-card {
  background: linear-gradient(155deg, #f9faff, #f0f2ff);
  border: 1px solid rgba(77, 88, 176, 0.13);
  border-radius: 16px;
  padding: 0.9rem;
}

.admin-stat-card p {
  margin: 0;
  color: #5d6698;
  font-size: 0.84rem;
}

.admin-stat-card strong {
  display: block;
  margin-top: 0.35rem;
  font-size: 1.7rem;
}

.admin-card {
  background: #fff;
  border: 1px solid rgba(17, 21, 50, 0.09);
  border-radius: 16px;
  padding: 0.9rem;
}

.admin-card h4 {
  margin: 0 0 0.8rem;
  font-size: 1rem;
  color: #202753;
}

.admin-recent-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 0.55rem;
}

.admin-recent-list li {
  border: 1px solid rgba(16, 22, 59, 0.08);
  border-radius: 12px;
  padding: 0.65rem 0.7rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 0.5rem;
}

.admin-recent-list li strong {
  display: block;
  color: #232a55;
}

.admin-recent-list li p {
  margin: 0.18rem 0 0;
  color: #5e6697;
  font-size: 0.88rem;
}

.admin-recent-list li span {
  font-size: 0.8rem;
  color: #7780af;
}

.admin-analytics-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0.7rem;
  margin-bottom: 0.7rem;
}

.mini-chart {
  min-height: 155px;
}

.mini-chart-bar {
  width: 34px;
  display: inline-flex;
  flex-direction: column;
  gap: 0.25rem;
  align-items: center;
  margin-right: 0.32rem;
}

.mini-chart-track {
  height: 112px;
  width: 100%;
  border-radius: 10px;
  background: rgba(95, 106, 255, 0.12);
  display: flex;
  align-items: flex-end;
}

.mini-chart-track span {
  width: 100%;
  border-radius: 10px;
  background: linear-gradient(180deg, #7780ff, #5560f6);
}

.mini-chart-bar strong {
  font-size: 0.8rem;
}

.mini-chart-bar em {
  font-size: 0.74rem;
  color: #6771a4;
  font-style: normal;
}

.line-chart-row {
  display: grid;
  grid-template-columns: minmax(95px, 1fr) 2fr auto;
  gap: 0.5rem;
  align-items: center;
  margin-bottom: 0.5rem;
}

.line-chart-row p {
  margin: 0;
  color: #3a4276;
  font-size: 0.85rem;
  word-break: break-all;
}

.line-chart-row div {
  border-radius: 999px;
  height: 9px;
  background: rgba(95, 106, 255, 0.11);
}

.line-chart-row div span {
  display: block;
  height: 100%;
  border-radius: 999px;
  background: linear-gradient(90deg, #7a83ff, #5d67f8);
}

.line-chart-row strong {
  font-size: 0.8rem;
}

.chart-empty {
  color: #7480ad;
  margin: 0;
}

.status-breakdown {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.status-row {
  display: grid;
  grid-template-columns: 50px 1fr auto;
  gap: 0.5rem;
  align-items: center;
}

.status-row p {
  margin: 0;
  color: #3a4276;
}

.status-row-track {
  height: 10px;
  background: rgba(95, 106, 255, 0.1);
  border-radius: 999px;
  overflow: hidden;
}

.status-row-track span {
  display: block;
  height: 100%;
  border-radius: 999px;
  background: linear-gradient(90deg, #7a83ff, #5d67f8);
}

.status-row strong {
  font-size: 0.82rem;
}

.admin-filters {
  display: grid;
  grid-template-columns: 2fr 140px;
  gap: 0.5rem;
  margin-bottom: 0.8rem;
}

.admin-filters select {
  border-radius: 12px;
  padding: 0.7rem 0.75rem;
  font-family: inherit;
}

.admin-table-wrap {
  overflow-x: auto;
}

.admin-table {
  width: 100%;
  border-collapse: collapse;
  min-width: 760px;
}

.admin-table th,
.admin-table td {
  text-align: left;
  padding: 0.7rem 0.55rem;
  border-bottom: 1px solid rgba(17, 21, 50, 0.1);
  font-size: 0.9rem;
  color: #23284f;
  vertical-align: top;
}

.admin-table th {
  font-size: 0.8rem;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: #6670a6;
}

.admin-delete {
  border: 1px solid rgba(214, 54, 54, 0.25);
  background: rgba(214, 54, 54, 0.08);
  color: #a83535;
  border-radius: 999px;
  padding: 0.36rem 0.75rem;
  font-size: 0.82rem;
  font-weight: 700;
  cursor: pointer;
}

@media (max-width: 1024px) {
  .admin-dashboard {
    grid-template-columns: 1fr;
    min-height: auto;
  }

  .admin-sidebar {
    padding: 0.9rem;
  }

  .admin-sidebar-menu {
    flex-direction: row;
    flex-wrap: wrap;
  }

  .sidebar-menu-btn {
    flex: 1;
    min-width: 100px;
    text-align: center;
  }

  .admin-stats-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .admin-analytics-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 700px) {
  .admin-auth {
    grid-template-columns: 1fr;
  }

  .admin-toolbar {
    flex-direction: column;
  }

  .admin-filters {
    grid-template-columns: 1fr;
  }
}