/* ===== Base ===== */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { font-size: 15px; }
body { font-family: 'Segoe UI', system-ui, sans-serif; background: #f0f2f5; color: #1e293b; line-height: 1.5; }
a { color: #2563eb; text-decoration: none; }
a:hover { text-decoration: underline; }
.container { max-width: 1200px; margin: 0 auto; padding: 0 1.5rem; }
.hflex { display: flex; align-items: center; gap: .75rem; flex-wrap: wrap; }

/* ===== Header ===== */
.app-header { background: #0f172a; color: #fff; padding: .85rem 0; position: sticky; top: 0; z-index: 100; box-shadow: 0 2px 8px rgba(0,0,0,.3); }
.logo { font-size: 1.15rem; font-weight: 700; letter-spacing: -.5px; }
.header-nav { display: flex; gap: .5rem; align-items: center; margin-left: auto; }
.header-nav a { color: #cbd5e1; padding: .3rem .75rem; border-radius: 5px; font-size: .9rem; transition: all .2s; }
.header-nav a:hover, .header-nav a.active { color: #fff; background: rgba(255,255,255,.1); text-decoration: none; }
.btn-nav.logout { color: #fca5a5 !important; }
.btn-nav.logout:hover { background: rgba(239,68,68,.2) !important; }

/* ===== Main Content ===== */
.main-content { padding: 2rem 0 3rem; min-height: calc(100vh - 130px); }
.page-hero { margin-bottom: 2rem; }
.page-hero h1 { font-size: 1.8rem; font-weight: 700; color: #0f172a; }
.page-hero p { color: #64748b; margin-top: .25rem; }

/* ===== Cards ===== */
.calc-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(280px, 1fr)); gap: 1.25rem; }
.calc-card { background: #fff; border-radius: 12px; padding: 1.5rem; box-shadow: 0 1px 4px rgba(0,0,0,.08); cursor: pointer; transition: transform .15s, box-shadow .15s; border: 1px solid #e2e8f0; }
.calc-card:hover { transform: translateY(-3px); box-shadow: 0 6px 20px rgba(0,0,0,.1); border-color: #2563eb; }
.calc-card-icon { font-size: 2rem; margin-bottom: .75rem; }
.calc-card h3 { font-size: 1.1rem; font-weight: 600; margin-bottom: .4rem; }
.calc-card p { color: #64748b; font-size: .9rem; margin-bottom: 1rem; min-height: 2.5rem; }
.empty-state { text-align: center; padding: 3rem; color: #64748b; background: #fff; border-radius: 12px; border: 2px dashed #e2e8f0; }

/* ===== Buttons ===== */
.btn { display: inline-flex; align-items: center; gap: .35rem; padding: .45rem 1rem; border-radius: 6px; border: none; cursor: pointer; font-size: .875rem; font-weight: 500; transition: all .15s; white-space: nowrap; }
.btn-primary { background: #2563eb; color: #fff; }
.btn-primary:hover { background: #1d4ed8; }
.btn-secondary { background: #64748b; color: #fff; }
.btn-secondary:hover { background: #475569; }
.btn-outline { background: transparent; border: 1.5px solid #d1d5db; color: #374151; }
.btn-outline:hover { border-color: #2563eb; color: #2563eb; background: #eff6ff; }
.btn-danger { background: #ef4444; color: #fff; }
.btn-danger:hover { background: #dc2626; }
.btn-text { background: none; border: none; color: #2563eb; padding: .25rem .5rem; }
.btn-text:hover { background: #eff6ff; }
.btn-sm { padding: .25rem .65rem; font-size: .8rem; }
.btn-block { width: 100%; justify-content: center; }
.btn-icon { padding: .25rem .5rem; font-size: 1rem; background: transparent; border: none; cursor: pointer; color: #64748b; border-radius: 4px; }
.btn-icon:hover { background: #f1f5f9; color: #1e293b; }
.btn-icon.danger:hover { color: #ef4444; background: #fef2f2; }

/* ===== Forms ===== */
label { display: block; font-size: .85rem; font-weight: 500; color: #374151; margin-bottom: .25rem; margin-top: .75rem; }
label:first-child { margin-top: 0; }
.form-control { width: 100%; padding: .45rem .7rem; border: 1.5px solid #d1d5db; border-radius: 6px; font-size: .875rem; background: #fff; transition: border-color .15s; }
.form-control:focus { outline: none; border-color: #2563eb; box-shadow: 0 0 0 3px rgba(37,99,235,.1); }
.form-control:read-only, .form-control[readonly] { background: #f8fafc; color: #64748b; }
textarea.form-control { resize: vertical; }
select.form-control { cursor: pointer; }
.form-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 1rem; }
.hint { font-size: .78rem; color: #94a3b8; margin-top: .2rem; }
.hint code { background: #f1f5f9; padding: .1rem .3rem; border-radius: 3px; font-family: monospace; }

/* ===== Alerts ===== */
.alert { padding: .65rem 1rem; border-radius: 6px; font-size: .875rem; margin-bottom: .75rem; }
.alert-error { background: #fef2f2; color: #dc2626; border: 1px solid #fecaca; }
.alert-success { background: #f0fdf4; color: #16a34a; border: 1px solid #bbf7d0; }
.alert-info { background: #eff6ff; color: #1d4ed8; border: 1px solid #bfdbfe; }

/* ===== Modals ===== */
.modal-overlay { position: fixed; inset: 0; background: rgba(0,0,0,.5); z-index: 1000; display: flex; align-items: center; justify-content: center; padding: 1rem; backdrop-filter: blur(2px); }
.modal { background: #fff; border-radius: 12px; width: 100%; max-width: 560px; max-height: 90vh; overflow-y: auto; box-shadow: 0 20px 60px rgba(0,0,0,.2); }
.modal-large { max-width: 760px; }
.modal-header { padding: 1.25rem 1.5rem; border-bottom: 1px solid #e2e8f0; display: flex; align-items: center; justify-content: space-between; position: sticky; top: 0; background: #fff; z-index: 1; }
.modal-header h3 { font-size: 1.05rem; font-weight: 600; }
.modal-close { background: none; border: none; font-size: 1.4rem; cursor: pointer; color: #94a3b8; line-height: 1; padding: .1rem .4rem; border-radius: 4px; }
.modal-close:hover { color: #1e293b; background: #f1f5f9; }
.modal-body { padding: 1.25rem 1.5rem; }
.modal-footer { padding: 1rem 1.5rem; border-top: 1px solid #e2e8f0; display: flex; gap: .5rem; justify-content: flex-end; }

/* ===== Footer ===== */
.app-footer { background: #0f172a; color: #64748b; text-align: center; padding: 1rem; font-size: .85rem; }

/* ===== Login ===== */
.login-screen { min-height: 100vh; background: linear-gradient(135deg, #0f172a 0%, #1e3a5f 100%); display: flex; align-items: center; justify-content: center; }
.login-card { background: #fff; border-radius: 16px; padding: 2.5rem; width: 100%; max-width: 360px; box-shadow: 0 25px 50px rgba(0,0,0,.3); }
.login-logo { font-size: 3rem; text-align: center; margin-bottom: .5rem; }
.login-card h2 { text-align: center; font-size: 1.5rem; font-weight: 700; }
.login-card > p { text-align: center; color: #64748b; margin-bottom: 1.5rem; }
.login-card .form-control { margin-bottom: .75rem; padding: .6rem .9rem; }
.login-card .btn { padding: .65rem 1rem; font-size: .95rem; }

/* ===== Admin Layout ===== */
.admin-layout { display: flex; min-height: calc(100vh - 60px); }
.admin-sidebar { width: 220px; min-width: 220px; background: #fff; border-right: 1px solid #e2e8f0; padding: 1.25rem 0; }
.sidebar-nav { display: flex; flex-direction: column; }
.sidebar-link { display: flex; align-items: center; gap: .6rem; padding: .65rem 1.25rem; color: #475569; font-size: .9rem; border-left: 3px solid transparent; transition: all .15s; }
.sidebar-link:hover { background: #f8fafc; color: #1e293b; text-decoration: none; }
.sidebar-link.active { background: #eff6ff; color: #2563eb; border-left-color: #2563eb; font-weight: 500; }
.sidebar-icon { font-size: 1rem; }
.admin-main { flex: 1; padding: 1.75rem 2rem; background: #f0f2f5; overflow-y: auto; }
.tab-header { margin-bottom: 1.5rem; justify-content: space-between; align-items: center; }
.tab-header h2 { font-size: 1.4rem; font-weight: 700; color: #0f172a; }

/* ===== Calc Admin List ===== */
.calc-admin-list { display: flex; flex-direction: column; gap: .75rem; }
.calc-admin-card { background: #fff; border-radius: 10px; padding: 1.25rem 1.5rem; display: flex; align-items: center; justify-content: space-between; box-shadow: 0 1px 3px rgba(0,0,0,.06); border: 1px solid #e2e8f0; }
.calc-admin-card h3 { font-size: 1rem; font-weight: 600; margin-bottom: .15rem; }
.calc-admin-card p { color: #64748b; font-size: .85rem; }
.calc-admin-actions { display: flex; gap: .4rem; }

/* ===== Builder ===== */
.builder-header { margin-bottom: 1.5rem; justify-content: space-between; align-items: flex-start; }
.builder-header h2 { font-size: 1.25rem; font-weight: 700; margin-top: .25rem; }
.section-list { display: flex; flex-direction: column; gap: .75rem; }
.section-card { background: #fff; border-radius: 10px; border: 1px solid #e2e8f0; overflow: hidden; box-shadow: 0 1px 3px rgba(0,0,0,.05); }
.section-card-header { padding: .9rem 1.25rem; display: flex; align-items: center; gap: .75rem; cursor: pointer; user-select: none; }
.section-card-header:hover { background: #f8fafc; }
.section-drag-handle { color: #94a3b8; cursor: grab; font-size: 1.1rem; }
.section-order-badge { background: #e0e7ff; color: #4338ca; font-size: .75rem; font-weight: 600; padding: .15rem .45rem; border-radius: 999px; }
.section-type-badge { background: #f1f5f9; color: #475569; font-size: .75rem; padding: .15rem .45rem; border-radius: 999px; border: 1px solid #e2e8f0; }
.section-card-title { flex: 1; font-weight: 600; font-size: .95rem; }
.section-card-actions { display: flex; gap: .3rem; }
.section-card-body { border-top: 1px solid #e2e8f0; padding: 1rem 1.25rem; display: none; }
.section-card-body.open { display: block; }
.col-list { display: flex; flex-direction: column; gap: .4rem; }
.col-item { background: #f8fafc; border: 1px solid #e2e8f0; border-radius: 6px; padding: .5rem .9rem; display: flex; align-items: center; gap: .75rem; }
.col-type-badge { font-size: .72rem; background: #dbeafe; color: #1d4ed8; padding: .1rem .4rem; border-radius: 3px; font-weight: 500; white-space: nowrap; }
.col-id { font-family: monospace; font-size: .8rem; color: #64748b; }

/* ===== Dropdown Master List ===== */
.master-list { display: flex; flex-direction: column; gap: .75rem; }
.master-card { background: #fff; border-radius: 10px; border: 1px solid #e2e8f0; overflow: hidden; }
.master-card-header { padding: .9rem 1.25rem; display: flex; align-items: center; justify-content: space-between; cursor: pointer; }
.master-card-header:hover { background: #f8fafc; }
.master-card-title { font-weight: 600; }
.master-card-body { border-top: 1px solid #e2e8f0; padding: 1rem 1.25rem; display: none; }
.master-card-body.open { display: block; }
.item-list { margin-bottom: .75rem; }
.item-row { display: flex; align-items: center; gap: .5rem; padding: .35rem .5rem; border-radius: 5px; }
.item-row:hover { background: #f8fafc; }
.item-key { font-family: monospace; font-size: .82rem; color: #64748b; min-width: 60px; }
.item-label { flex: 1; font-size: .88rem; }
.item-value { font-size: .82rem; color: #0369a1; background: #e0f2fe; padding: .1rem .4rem; border-radius: 3px; min-width: 50px; text-align: right; }
.child-items { margin-left: 1.5rem; margin-top: .25rem; border-left: 2px solid #e0e7ff; padding-left: .75rem; }

/* ===== Columns Editor ===== */
.columns-editor { display: flex; flex-direction: column; gap: .5rem; }
.col-editor-row { background: #f8fafc; border: 1px solid #e2e8f0; border-radius: 8px; padding: .65rem .9rem; display: flex; align-items: center; gap: .75rem; cursor: default; transition: opacity .15s, box-shadow .15s; }
.col-editor-info { flex: 1; }
.col-editor-info strong { font-size: .88rem; }
.col-editor-info span { font-size: .78rem; color: #64748b; margin-left: .4rem; }
.col-drag-handle { color: #94a3b8; cursor: grab; font-size: 1.1rem; line-height: 1; padding: 0 .1rem; flex-shrink: 0; user-select: none; }
.col-drag-handle:active { cursor: grabbing; }
.col-editor-row.dragging { opacity: .4; box-shadow: none; }
.col-editor-row.drag-over-top { border-top: 2px solid #6366f1; }
.col-editor-row.drag-over-bottom { border-bottom: 2px solid #6366f1; }

/* ===== Settings ===== */
.settings-card { background: #fff; border-radius: 10px; padding: 1.5rem; border: 1px solid #e2e8f0; max-width: 500px; }
.settings-card h3 { font-size: 1rem; font-weight: 600; margin-bottom: 1rem; }

/* ===== Calculation View ===== */
.calc-actions { display: flex; gap: .5rem; }
.calc-section { background: #fff; border-radius: 12px; border: 1px solid #e2e8f0; margin-bottom: 1.5rem; overflow: hidden; box-shadow: 0 1px 4px rgba(0,0,0,.05); }
.section-header { padding: .85rem 1.5rem; background: #0f172a; color: #fff; display: flex; align-items: center; gap: .75rem; }
.section-header h3 { font-size: 1rem; font-weight: 600; }
.section-order { background: rgba(255,255,255,.15); font-size: .75rem; padding: .15rem .45rem; border-radius: 999px; }
.section-body { padding: 1.25rem 1.5rem; overflow-x: auto; }

/* ===== Tables ===== */
.calc-table { width: 100%; border-collapse: collapse; font-size: .875rem; }
.calc-table th { background: #f8fafc; padding: .6rem .75rem; text-align: left; font-weight: 600; color: #374151; border-bottom: 2px solid #e2e8f0; white-space: nowrap; }
.calc-table td { padding: .45rem .75rem; border-bottom: 1px solid #f1f5f9; vertical-align: middle; }
.calc-table tr:last-child td { border-bottom: none; }
.calc-table tr:hover td { background: #fafafa; }
.calc-table .locked-cell { background: #f8fafc; color: #64748b; font-weight: 500; text-align: right; padding-right: 1rem; }
.locked-wrap { display: flex; align-items: center; gap: .35rem; }
.locked-wrap .locked-cell { flex: 1; display: block; padding: .3rem .6rem; border-radius: 4px; }
.locked-wrap input.number-input { flex: 1; }
.lock-btn { background: #f1f5f9; border: 1px solid #e2e8f0; cursor: pointer; padding: .25rem .45rem; border-radius: 4px; font-size: .9rem; line-height: 1; color: #475569; transition: all .15s; }
.lock-btn:hover { background: #e0e7ff; border-color: #6366f1; color: #4338ca; }
.lock-btn.unlocked { background: #fef3c7; border-color: #fde68a; color: #92400e; }
.lock-btn.unlocked:hover { background: #fde68a; }
.calc-table .formula-cell { background: #eff6ff; color: #1d4ed8; font-weight: 500; text-align: right; }
.calc-table .number-input { width: 100px; text-align: right; }
.calc-table select.form-control, .calc-table input.form-control { padding: .3rem .5rem; font-size: .84rem; }
.calc-table .others-input { margin-top: .25rem; font-size: .82rem; padding: .25rem .5rem; border: 1.5px solid #93c5fd; border-radius: 4px; width: 100%; }

/* Summary Row */
.summary-section { margin-top: 1rem; padding-top: 1rem; border-top: 2px solid #e2e8f0; }
.summary-row-display { display: flex; justify-content: flex-end; gap: 2rem; flex-wrap: wrap; }
.summary-item { text-align: right; }
.summary-item .s-label { font-size: .78rem; color: #64748b; text-transform: uppercase; letter-spacing: .5px; }
.summary-item .s-value { font-size: 1.25rem; font-weight: 700; color: #0f172a; }
.s-value-wrap { display: flex; align-items: center; justify-content: flex-end; gap: .4rem; }

/* Copy Value Button */
.copy-val-btn { background: none; border: none; cursor: pointer; font-size: .85rem; padding: .15rem .3rem; border-radius: 4px; line-height: 1; transition: all .15s; opacity: 0; color: #94a3b8; }
.summary-item:hover .copy-val-btn { opacity: 1; }
.copy-val-btn:hover { color: #2563eb; background: #eff6ff; }
.copy-val-btn.copied { color: #16a34a !important; opacity: 1 !important; }
.copy-val-btn--card { position: absolute; top: .6rem; right: .6rem; color: rgba(255,255,255,.5); opacity: 1; font-size: .9rem; }
.formula-result-card:hover .copy-val-btn--card { color: rgba(255,255,255,.85); }
.copy-val-btn--card:hover { background: rgba(255,255,255,.2) !important; color: #fff !important; }
.copy-val-btn--card.copied { color: #86efac !important; }

/* Formula Display Section */
.formula-display-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(220px, 1fr)); gap: 1rem; }
.formula-result-card { background: linear-gradient(135deg, #1e40af 0%, #0369a1 100%); color: #fff; border-radius: 10px; padding: 1.25rem; position: relative; }
.formula-result-card .f-label { font-size: .82rem; opacity: .85; margin-bottom: .35rem; }
.formula-result-card .f-value { font-size: 2rem; font-weight: 700; }
.formula-result-card .f-desc { font-size: .75rem; opacity: .7; margin-top: .35rem; }

/* Calc Ref Section */
.calc-ref-notice { background: #fefce8; border: 1px solid #fde047; border-radius: 8px; padding: .75rem 1rem; display: flex; align-items: center; gap: .75rem; font-size: .875rem; color: #713f12; margin-bottom: .75rem; }

/* Add Row Button */
.add-row-area { margin-top: .75rem; }
.remove-row-btn { background: none; border: none; cursor: pointer; color: #94a3b8; font-size: 1rem; padding: .2rem .4rem; border-radius: 4px; }
.remove-row-btn:hover { color: #ef4444; background: #fef2f2; }

.visibility-badge { display: inline-flex; align-items: center; padding: .1rem .45rem; border-radius: 999px; background: #dcfce7; color: #166534; font-size: .7rem; font-weight: 700; text-transform: uppercase; letter-spacing: .02em; }
.visibility-badge.hidden { background: #fee2e2; color: #991b1b; }
.visibility-checkbox { display: inline-flex; align-items: center; gap: .45rem; margin: .75rem 0 1rem; color: #475569; font-weight: 500; }

/* ===== Loading ===== */
.loading-state { text-align: center; padding: 2rem; color: #94a3b8; }
.loading-state::before { content: '⟳'; display: block; font-size: 2rem; animation: spin 1s linear infinite; margin-bottom: .5rem; }
@keyframes spin { to { transform: rotate(360deg); } }

/* ===== Saved Results ===== */
.result-item { display: flex; align-items: center; justify-content: space-between; padding: .65rem .75rem; border-bottom: 1px solid #f1f5f9; }
.result-item:last-child { border-bottom: none; }
.result-item .r-name { font-weight: 500; font-size: .9rem; }
.result-item .r-date { font-size: .78rem; color: #94a3b8; }
.result-item .r-actions { display: flex; gap: .3rem; }

/* ===== Responsive ===== */
@media (max-width: 768px) {
  .admin-layout { flex-direction: column; }
  .admin-sidebar { width: 100%; min-width: 0; border-right: none; border-bottom: 1px solid #e2e8f0; padding: .5rem 0; }
  .sidebar-nav { flex-direction: row; overflow-x: auto; }
  .sidebar-link { border-left: none; border-bottom: 3px solid transparent; padding: .5rem .9rem; white-space: nowrap; }
  .sidebar-link.active { border-bottom-color: #2563eb; }
  .admin-main { padding: 1rem; }
  .form-grid { grid-template-columns: 1fr; }
  .page-hero.hflex { flex-direction: column; align-items: flex-start; }
}