/* ─────────────────────────────────────────
   CSS Variables & Reset
───────────────────────────────────────── */
:root {
  --bg:          #f5f4f0;
  --surface:     #ffffff;
  --border:      #e2e0da;
  --border-dark: #c8c5bc;

  --navy:        #1a2740;
  --navy-mid:    #2e3f5c;
  --navy-light:  #4a6080;

  --amber:       #e8a020;
  --amber-light: #fdf3e0;
  --amber-dark:  #b87a10;

  --green:       #2d7a4f;
  --green-light: #e8f5ee;
  --red:         #c0392b;
  --red-light:   #fdecea;

  --text-primary:   #1a2740;
  --text-secondary: #5a6a80;
  --text-muted:     #9aacbf;

  --radius-sm: 6px;
  --radius:    12px;
  --radius-lg: 18px;

  --shadow-sm: 0 1px 4px rgba(26,39,64,0.07);
  --shadow:    0 4px 16px rgba(26,39,64,0.10);
  --shadow-lg: 0 8px 32px rgba(26,39,64,0.14);

  --font-body:    'Noto Sans KR', sans-serif;
  --font-display: 'Playfair Display', Georgia, serif;
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html { font-size: 15px; }

body {
  font-family: var(--font-body);
  background: var(--bg);
  color: var(--text-primary);
  line-height: 1.6;
  min-height: 100vh;
}

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

/* ─────────────────────────────────────────
   BG Grid Pattern
───────────────────────────────────────── */
.bg-grid {
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 0;
  background-image:
    linear-gradient(rgba(26,39,64,0.03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(26,39,64,0.03) 1px, transparent 1px);
  background-size: 40px 40px;
}

/* ─────────────────────────────────────────
   Header
───────────────────────────────────────── */
.main-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(26,39,64,0.96);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid rgba(255,255,255,0.08);
}

.header-inner {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 28px;
  height: 64px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.logo { display: flex; align-items: center; gap: 12px; }

.logo-mark {
  width: 36px; height: 36px;
  background: var(--amber);
  border-radius: var(--radius-sm);
  display: flex; align-items: center; justify-content: center;
  font-family: var(--font-display);
  font-size: 18px;
  font-weight: 700;
  color: var(--navy);
  flex-shrink: 0;
}

.logo-title {
  font-size: 0.95rem;
  font-weight: 700;
  color: #fff;
  letter-spacing: -0.02em;
  display: block;
}

.logo-sub {
  font-size: 0.68rem;
  color: rgba(255,255,255,0.45);
  letter-spacing: 0.05em;
  display: block;
  margin-top: -1px;
}

.header-date {
  font-size: 0.8rem;
  color: rgba(255,255,255,0.5);
  letter-spacing: 0.01em;
}

.header-right { display: flex; align-items: center; gap: 16px; }

.btn-back {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 7px 14px;
  border-radius: var(--radius-sm);
  background: rgba(255,255,255,0.08);
  color: rgba(255,255,255,0.7);
  font-size: 0.8rem;
  font-family: var(--font-body);
  border: none;
  cursor: pointer;
  transition: background 0.2s, color 0.2s;
}
.btn-back:hover { background: rgba(255,255,255,0.14); color: #fff; }

/* ─────────────────────────────────────────
   Landing Page
───────────────────────────────────────── */
.landing-body { background: var(--bg); }

.landing-main {
  position: relative;
  z-index: 1;
  max-width: 1100px;
  margin: 0 auto;
  padding: 60px 28px 80px;
}

/* Hero */
.hero { margin-bottom: 64px; }

.hero-eyebrow {
  font-size: 0.75rem;
  font-weight: 500;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--amber);
  margin-bottom: 12px;
}

.hero-title {
  font-family: var(--font-display);
  font-size: clamp(2.4rem, 5vw, 3.6rem);
  font-weight: 700;
  line-height: 1.15;
  color: var(--navy);
  letter-spacing: -0.03em;
  margin-bottom: 16px;
}

.hero-desc {
  font-size: 1rem;
  color: var(--text-secondary);
  font-weight: 300;
}

/* Features */
.section-label {
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--text-muted);
  margin-bottom: 20px;
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 20px;
}

.feature-card {
  position: relative;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 28px;
  display: flex;
  flex-direction: column;
  gap: 20px;
  overflow: hidden;
  transition: transform 0.2s, box-shadow 0.2s, border-color 0.2s;
  cursor: pointer;
}

.feature-card:not(.disabled):hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-lg);
  border-color: var(--amber);
}

.feature-card.disabled {
  cursor: default;
  opacity: 0.55;
}

.card-accent {
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--amber), var(--amber-dark));
  border-radius: var(--radius-lg) var(--radius-lg) 0 0;
}

.card-header { display: flex; align-items: flex-start; justify-content: space-between; }

.card-icon-wrap {
  width: 52px; height: 52px;
  background: var(--amber-light);
  border-radius: var(--radius);
  display: flex; align-items: center; justify-content: center;
  color: var(--amber-dark);
}

.card-icon-wrap.muted { background: #f0f0f0; color: #aaa; }

.card-status {
  font-size: 0.68rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  padding: 3px 10px;
  border-radius: 20px;
}

.card-status.active { background: var(--green-light); color: var(--green); }
.card-status.coming { background: #f0f0f0; color: #999; }

.card-title {
  font-size: 1.05rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: 6px;
}
.card-title.muted { color: #aaa; }

.card-desc { font-size: 0.85rem; color: var(--text-secondary); line-height: 1.6; }
.card-desc.muted { color: #bbb; }

.card-footer { margin-top: auto; }

.card-link {
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--navy);
}

.card-link .arrow {
  display: inline-block;
  transition: transform 0.2s;
}
.feature-card:hover .arrow { transform: translateX(4px); }

/* Footer */
.main-footer {
  position: relative; z-index: 1;
  text-align: center;
  padding: 24px;
  font-size: 0.75rem;
  color: var(--text-muted);
  border-top: 1px solid var(--border);
}

/* ─────────────────────────────────────────
   Settlement Page
───────────────────────────────────────── */
.settlement-body { background: var(--bg); }

.settlement-main {
  position: relative; z-index: 1;
  max-width: 900px;
  margin: 0 auto;
  padding: 40px 28px 80px;
}

/* Page Title */
.page-title-bar { margin-bottom: 36px; }
.page-eyebrow {
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--amber);
  margin-bottom: 6px;
}
.page-title {
  font-family: var(--font-display);
  font-size: 1.9rem;
  font-weight: 700;
  letter-spacing: -0.03em;
  color: var(--navy);
}

/* Settings Panel */
.settings-panel {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  margin-bottom: 28px;
  overflow: hidden;
}

.settings-toggle {
  width: 100%;
  padding: 16px 20px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: none;
  border: none;
  cursor: pointer;
  font-family: var(--font-body);
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text-secondary);
  transition: background 0.15s;
}
.settings-toggle:hover { background: var(--bg); }

.settings-toggle-icon { transition: transform 0.2s; }
.settings-toggle.open .settings-toggle-icon { transform: rotate(180deg); }

.settings-body {
  padding: 20px;
  border-top: 1px solid var(--border);
  display: none;
}
.settings-body.open { display: block; }

.settings-hint {
  font-size: 0.8rem;
  color: var(--text-muted);
  margin-bottom: 12px;
  line-height: 1.5;
}

.settings-hint a { color: var(--amber-dark); text-decoration: underline; }

.input-group { display: flex; gap: 10px; }

.input-full {
  flex: 1;
  padding: 10px 14px;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  font-family: var(--font-body);
  font-size: 0.85rem;
  color: var(--text-primary);
  background: var(--bg);
  transition: border-color 0.15s;
}
.input-full:focus { outline: none; border-color: var(--amber); }

.conn-status {
  display: flex;
  align-items: center;
  gap: 6px;
  margin-top: 10px;
  font-size: 0.78rem;
}

.conn-dot {
  width: 7px; height: 7px;
  border-radius: 50%;
  background: #ccc;
}
.conn-dot.connected { background: var(--green); }
.conn-dot.error { background: var(--red); }

/* Search Bar */
.search-bar {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  margin-bottom: 24px;
  display: flex;
  gap: 12px;
  align-items: flex-end;
}

.form-field { flex: 1; }
.form-label {
  display: block;
  font-size: 0.78rem;
  font-weight: 600;
  color: var(--text-secondary);
  letter-spacing: 0.04em;
  margin-bottom: 7px;
}

.input-main {
  width: 100%;
  padding: 12px 16px;
  border: 1.5px solid var(--border);
  border-radius: var(--radius-sm);
  font-family: var(--font-body);
  font-size: 1rem;
  color: var(--text-primary);
  background: var(--bg);
  transition: border-color 0.15s, box-shadow 0.15s;
}
.input-main:focus {
  outline: none;
  border-color: var(--amber);
  box-shadow: 0 0 0 3px rgba(232,160,32,0.15);
}

/* Buttons */
.btn {
  padding: 12px 22px;
  border: none;
  border-radius: var(--radius-sm);
  font-family: var(--font-body);
  font-size: 0.9rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.15s;
  white-space: nowrap;
}

.btn-primary {
  background: var(--navy);
  color: #fff;
}
.btn-primary:hover { background: var(--navy-mid); }
.btn-primary:disabled { background: #ccc; cursor: not-allowed; }

.btn-amber {
  background: var(--amber);
  color: var(--navy);
}
.btn-amber:hover { background: var(--amber-dark); color: #fff; }

.btn-outline {
  background: transparent;
  color: var(--navy);
  border: 1.5px solid var(--border-dark);
}
.btn-outline:hover { border-color: var(--navy); background: var(--bg); }

.btn-sm { padding: 7px 14px; font-size: 0.8rem; }
.btn-icon { display: flex; align-items: center; gap: 6px; }

/* Student Info Card */
.student-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px 24px;
  margin-bottom: 24px;
  display: none;
}

.student-card.visible { display: block; }

.student-card-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 16px;
}

.student-card-title {
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-muted);
}

.student-info-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(130px, 1fr));
  gap: 12px;
}

.info-item { }

.info-label {
  font-size: 0.7rem;
  font-weight: 600;
  color: var(--text-muted);
  letter-spacing: 0.05em;
  margin-bottom: 3px;
}

.info-value {
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--navy);
}

.info-value.empty { color: var(--text-muted); font-weight: 400; font-style: italic; }

/* Textbook Table Section */
.section-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  margin-bottom: 24px;
  overflow: hidden;
  display: none;
}

.section-card.visible { display: block; }

.section-card-header {
  padding: 18px 24px;
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: #fafaf8;
}

.section-card-title {
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--navy);
  display: flex;
  align-items: center;
  gap: 8px;
}

.count-badge {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 22px;
  height: 22px;
  padding: 0 7px;
  background: var(--navy);
  color: #fff;
  border-radius: 20px;
  font-size: 0.72rem;
  font-weight: 700;
}

/* Table */
.table-wrap { overflow-x: auto; }

.data-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.85rem;
}

.data-table th {
  padding: 10px 14px;
  text-align: left;
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--text-muted);
  background: #fafaf8;
  border-bottom: 1px solid var(--border);
  white-space: nowrap;
}

.data-table td {
  padding: 12px 14px;
  border-bottom: 1px solid var(--border);
  vertical-align: middle;
}

.data-table tr:last-child td { border-bottom: none; }

.data-table tr.flagged { background: var(--red-light); }
.data-table tr.row-unchecked { opacity: 0.4; background: #f8f8f6; }

.flag-checkbox {
  width: 16px; height: 16px;
  cursor: pointer;
  accent-color: var(--red);
}

.price-cell { font-weight: 600; color: var(--navy); }
.date-cell { color: var(--text-secondary); font-size: 0.8rem; }
.code-cell { color: var(--text-muted); font-family: monospace; font-size: 0.8rem; }

.note-input {
  width: 100%;
  padding: 5px 8px;
  border: 1px solid var(--border);
  border-radius: 4px;
  font-family: var(--font-body);
  font-size: 0.8rem;
  background: transparent;
  color: var(--text-secondary);
  min-width: 120px;
}
.note-input:focus { outline: none; border-color: var(--amber); }

/* Empty / Loading States */
.table-placeholder {
  padding: 48px 24px;
  text-align: center;
  color: var(--text-muted);
}

.table-placeholder .placeholder-icon { font-size: 2.5rem; margin-bottom: 10px; }
.table-placeholder p { font-size: 0.85rem; }

.spinner {
  width: 28px; height: 28px;
  border: 3px solid var(--border);
  border-top-color: var(--navy);
  border-radius: 50%;
  animation: spin 0.7s linear infinite;
  margin: 0 auto 12px;
}
@keyframes spin { to { transform: rotate(360deg); } }

/* Summary Section */
.summary-section {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  margin-bottom: 24px;
  display: none;
}

.summary-section.visible { display: block; }

.summary-title {
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-muted);
  margin-bottom: 20px;
}

.summary-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
  margin-bottom: 20px;
}

.summary-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 10px 0;
  border-bottom: 1px solid var(--border);
}

.summary-row:last-child { border-bottom: none; }

.summary-label {
  font-size: 0.85rem;
  color: var(--text-secondary);
}

.summary-value {
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--navy);
}

.summary-value.red { color: var(--red); }
.summary-value.green { color: var(--green); }

/* Refund Input Area */
.refund-area {
  background: var(--amber-light);
  border: 1px solid #f0d080;
  border-radius: var(--radius-sm);
  padding: 16px 20px;
}

.refund-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}

.refund-label {
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--navy);
  white-space: nowrap;
}

.refund-inputs { display: flex; gap: 8px; align-items: center; }

.input-money {
  width: 150px;
  padding: 9px 12px;
  border: 1.5px solid #e0c060;
  border-radius: var(--radius-sm);
  font-family: var(--font-body);
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--navy);
  background: #fff;
  text-align: right;
}
.input-money:focus { outline: none; border-color: var(--amber); }

.total-box {
  margin-top: 16px;
  padding: 16px 20px;
  background: var(--navy);
  border-radius: var(--radius-sm);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.total-label { font-size: 0.9rem; font-weight: 600; color: rgba(255,255,255,0.7); }
.total-value { font-size: 1.3rem; font-weight: 700; color: #fff; }

/* Action Bar */
.action-bar {
  display: flex;
  gap: 12px;
  justify-content: flex-end;
  flex-wrap: wrap;
  display: none;
}

.action-bar.visible { display: flex; }

/* Messages */
.toast {
  position: fixed;
  bottom: 28px;
  left: 50%;
  transform: translateX(-50%) translateY(10px);
  background: var(--navy);
  color: #fff;
  padding: 12px 22px;
  border-radius: var(--radius);
  font-size: 0.85rem;
  opacity: 0;
  transition: opacity 0.3s, transform 0.3s;
  z-index: 999;
  pointer-events: none;
  white-space: nowrap;
}

.toast.show {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}

/* ─────────────────────────────────────────
   Print Styles
───────────────────────────────────────── */
@media print {
  * { -webkit-print-color-adjust: exact !important; print-color-adjust: exact !important; }

  .bg-grid,
  .main-header,
  .settings-panel,
  .search-bar,
  .action-bar,
  .flag-checkbox,
  .note-input,
  .refund-inputs,
  .btn,
  .toast { display: none !important; }

  .settlement-main { padding: 0; max-width: 100%; }

  .student-card,
  .section-card,
  .summary-section { display: block !important; box-shadow: none !important; border: 1px solid #ccc !important; }

  .print-header {
    display: block !important;
    margin-bottom: 20px;
  }

  .data-table th, .data-table td { padding: 7px 10px; font-size: 0.8rem; }

  .note-print { font-size: 0.78rem; color: #666; }

  body { background: #fff; }
}

/* Print-only header */
.print-header {
  display: none;
}

/* Responsive */
@media (max-width: 640px) {
  .search-bar { flex-direction: column; }
  .summary-grid { grid-template-columns: 1fr; }
  .refund-row { flex-direction: column; align-items: flex-start; }
}