/* ==========================================================================
   School Management System - design system (tokens, base, components)
   ========================================================================== */
:root{
  --bg:#f5f7fb; --surface:#ffffff; --surface-2:#f0f3f9; --border:#e3e8f1; --border-strong:#cfd7e6;
  --text:#0f1b3d; --text-2:#46547a; --muted:#7482a3;
  --primary:#3b4fe0; --primary-600:#2f41c8; --primary-700:#2635a6; --primary-50:#eef0ff; --primary-100:#dfe3ff;
  --cyan:#0ea5c6; --emerald:#10a56e; --violet:#7c4ddb; --amber:#f0a30a; --rose:#e5484d;
  --cyan-50:#e4f7fb; --emerald-50:#e3f6ee; --violet-50:#f0eafd; --amber-50:#fdf3dc; --rose-50:#fdeaea;
  --grad-primary:linear-gradient(135deg,#4a5cf0 0%,#3445d6 55%,#2a37b8 100%);
  --grad-hero:linear-gradient(135deg,#1e2a78 0%,#3b4fe0 55%,#4b8bf5 100%);
  --shadow-xs:0 1px 2px rgba(15,27,61,.06);
  --shadow-sm:0 2px 6px rgba(15,27,61,.06),0 1px 2px rgba(15,27,61,.04);
  --shadow-md:0 8px 24px rgba(15,27,61,.08),0 2px 6px rgba(15,27,61,.04);
  --shadow-lg:0 18px 48px rgba(31,45,120,.16),0 4px 12px rgba(15,27,61,.06);
  --radius-sm:8px; --radius:12px; --radius-lg:18px; --radius-xl:24px;
  --font:"Inter","Segoe UI",system-ui,-apple-system,"Helvetica Neue",Arial,sans-serif;
  --sidebar-w:264px; --topbar-h:68px; --ease:cubic-bezier(.22,.8,.3,1);
}
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth}
body{margin:0;font-family:var(--font);font-size:15px;line-height:1.55;color:var(--text);background:var(--bg);-webkit-font-smoothing:antialiased;overflow-x:hidden}
img,svg{max-width:100%}
img{display:block;height:auto}
a{color:var(--primary);text-decoration:none}
a:hover{color:var(--primary-700)}
h1,h2,h3,h4{line-height:1.25;margin:0 0 .5em;color:var(--text);letter-spacing:-.01em}
h1{font-size:1.75rem;font-weight:750}h2{font-size:1.3rem;font-weight:700}h3{font-size:1.05rem;font-weight:650}
p{margin:0 0 1em}
.muted{color:var(--muted)}.text-2{color:var(--text-2)}.small{font-size:.85rem}.xs{font-size:.78rem}
.right{text-align:right}.center{text-align:center}.nowrap{white-space:nowrap}
.sr-only{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap}
.icon{flex:none;vertical-align:middle}
.center-screen{min-height:100vh;display:grid;place-items:center;padding:1rem}
:focus-visible{outline:3px solid rgba(59,79,224,.35);outline-offset:2px;border-radius:6px}
::selection{background:var(--primary-100)}

/* ---------- Buttons ---------- */
.btn{--h:42px;display:inline-flex;align-items:center;justify-content:center;gap:.5rem;min-height:var(--h);padding:0 1.15rem;border:1.5px solid transparent;border-radius:var(--radius);
  font:600 .9rem/1 var(--font);letter-spacing:.005em;cursor:pointer;text-decoration:none;white-space:nowrap;position:relative;user-select:none;
  transition:transform .15s var(--ease),box-shadow .2s var(--ease),background .2s,border-color .2s,color .2s,filter .2s;-webkit-tap-highlight-color:transparent}
.btn:active:not(:disabled):not(.is-loading){transform:translateY(1px) scale(.985)}
.btn-primary{color:#fff;background:var(--grad-primary);box-shadow:0 6px 16px rgba(52,69,214,.32),inset 0 1px 0 rgba(255,255,255,.18)}
.btn-primary:hover{color:#fff;box-shadow:0 10px 22px rgba(52,69,214,.4),inset 0 1px 0 rgba(255,255,255,.2);transform:translateY(-1px);filter:brightness(1.04)}
.btn-secondary{color:var(--primary-700);background:var(--primary-50);border-color:var(--primary-100)}
.btn-secondary:hover{background:var(--primary-100);color:var(--primary-700)}
.btn-outline{color:var(--text);background:var(--surface);border-color:var(--border-strong)}
.btn-outline:hover{border-color:var(--primary);color:var(--primary);background:var(--primary-50)}
.btn-ghost{color:var(--text-2);background:transparent}
.btn-ghost:hover{background:var(--surface-2);color:var(--text)}
.btn-danger{color:#fff;background:linear-gradient(135deg,#ee5a5f,#d63a40);box-shadow:0 6px 16px rgba(214,58,64,.28)}
.btn-danger:hover{color:#fff;transform:translateY(-1px);box-shadow:0 10px 22px rgba(214,58,64,.36)}
.btn-danger-soft{color:#c4282e;background:var(--rose-50);border-color:#f8d0d2}
.btn-danger-soft:hover{background:#fbd9db;color:#a81f25}
.btn-success{color:#fff;background:linear-gradient(135deg,#19b87c,#0e8f5f);box-shadow:0 6px 16px rgba(16,165,110,.28)}
.btn-success:hover{color:#fff;transform:translateY(-1px)}
.btn-sm{--h:34px;padding:0 .85rem;font-size:.82rem;border-radius:10px}
.btn-lg{--h:50px;padding:0 1.6rem;font-size:1rem;border-radius:14px}
.btn-block{width:100%}
.btn-pill{border-radius:999px}
.btn-icon{--h:38px;width:38px;padding:0;color:var(--text-2);background:transparent;border-radius:10px}
.btn-icon:hover{background:var(--surface-2);color:var(--primary)}
.btn-icon.btn-sm{width:32px;--h:32px}
.btn:disabled,.btn.is-disabled{opacity:.55;cursor:not-allowed;box-shadow:none;transform:none;filter:grayscale(.2)}
.btn.is-loading{color:transparent!important;pointer-events:none}
.btn.is-loading::after{content:"";position:absolute;width:18px;height:18px;border-radius:50%;border:2.5px solid rgba(255,255,255,.45);border-top-color:#fff;animation:spin .7s linear infinite}
.btn-outline.is-loading::after,.btn-secondary.is-loading::after,.btn-ghost.is-loading::after,.btn-icon.is-loading::after{border-color:rgba(59,79,224,.25);border-top-color:var(--primary)}
@keyframes spin{to{transform:rotate(360deg)}}
.btn-group{display:flex;flex-wrap:wrap;gap:.6rem;align-items:center}

/* ---------- Cards, badges ---------- */
.card{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius-lg);box-shadow:var(--shadow-sm)}
.card-pad{padding:1.25rem}
.card-head{display:flex;align-items:center;justify-content:space-between;gap:1rem;padding:1rem 1.25rem;border-bottom:1px solid var(--border)}
.card-head h2,.card-head h3{margin:0}
.card-body{padding:1.25rem}
.card-hover{transition:transform .25s var(--ease),box-shadow .25s var(--ease)}
.card-hover:hover{transform:translateY(-3px);box-shadow:var(--shadow-md)}
.badge{display:inline-flex;align-items:center;gap:.3rem;padding:.2rem .6rem;border-radius:999px;font-size:.74rem;font-weight:650;line-height:1.4;background:var(--surface-2);color:var(--text-2)}
.badge-primary{background:var(--primary-50);color:var(--primary-700)}
.badge-success{background:var(--emerald-50);color:#0b7a50}
.badge-warning{background:var(--amber-50);color:#9a6700}
.badge-danger{background:var(--rose-50);color:#b3282d}
.badge-info{background:var(--cyan-50);color:#0a7c96}
.badge-violet{background:var(--violet-50);color:#5b34b3}
.icon-badge{display:inline-grid;place-items:center;width:44px;height:44px;border-radius:13px;flex:none}
.tone-primary{background:var(--primary-50);color:var(--primary)}.tone-cyan{background:var(--cyan-50);color:var(--cyan)}
.tone-emerald{background:var(--emerald-50);color:var(--emerald)}.tone-violet{background:var(--violet-50);color:var(--violet)}
.tone-amber{background:var(--amber-50);color:#d98e00}.tone-rose{background:var(--rose-50);color:var(--rose)}.tone-slate{background:var(--surface-2);color:var(--text-2)}
.avatar{width:40px;height:40px;border-radius:50%;object-fit:cover;background:var(--primary-100);color:var(--primary-700);display:inline-grid;place-items:center;font-weight:700;font-size:.85rem;flex:none}

/* ---------- Forms ---------- */
.form-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(220px,1fr));gap:1rem 1.1rem}
.form-grid .span-2{grid-column:span 2}.form-grid .span-all{grid-column:1/-1}
.field{display:flex;flex-direction:column;gap:.35rem;min-width:0}
.field label,.label{font-size:.82rem;font-weight:650;color:var(--text-2)}
.field .req{color:var(--rose)}
.input,.select,.textarea{width:100%;min-height:44px;padding:.65rem .9rem;font:500 .93rem/1.3 var(--font);color:var(--text);background:var(--surface);border:1.5px solid var(--border-strong);border-radius:var(--radius);transition:border-color .2s,box-shadow .2s,background .2s}
.textarea{min-height:96px;resize:vertical;line-height:1.5}
.input::placeholder,.textarea::placeholder{color:#a3aec6}
.input:hover,.select:hover,.textarea:hover{border-color:#b6c1d9}
.input:focus,.select:focus,.textarea:focus{outline:none;border-color:var(--primary);box-shadow:0 0 0 4px rgba(59,79,224,.14)}
.input[aria-invalid="true"],.is-invalid{border-color:var(--rose)}
.select{appearance:none;background-image:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='16' height='16' viewBox='0 0 24 24' fill='none' stroke='%237482a3' stroke-width='2.2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='m6 9.5 6 6 6-6'/%3E%3C/svg%3E");background-repeat:no-repeat;background-position:right .8rem center;padding-right:2.4rem}
.field-error{color:#c4282e;font-size:.8rem;font-weight:550}
.field-hint{color:var(--muted);font-size:.78rem}
.input-icon{position:relative}.input-icon>.icon{position:absolute;left:.85rem;top:50%;transform:translateY(-50%);color:var(--muted);pointer-events:none}
.input-icon .input{padding-left:2.6rem}
.input-icon .toggle-pass{position:absolute;right:.35rem;top:50%;transform:translateY(-50%)}
.check{display:inline-flex;align-items:center;gap:.5rem;font-weight:550;cursor:pointer}
.check input{width:18px;height:18px;accent-color:var(--primary)}
.filter-bar{display:flex;flex-wrap:wrap;gap:.7rem;align-items:flex-end;padding:1rem 1.25rem;border-bottom:1px solid var(--border)}
.filter-bar .field{min-width:150px;flex:1 1 150px}.filter-bar .field.grow{flex:2 1 240px}

/* ---------- Alerts / toasts ---------- */
.alert{display:flex;gap:.7rem;align-items:flex-start;padding:.85rem 1rem;border-radius:var(--radius);border:1px solid;font-size:.9rem;margin-bottom:1rem}
.alert-success{background:var(--emerald-50);border-color:#b9e8d3;color:#0b6e48}
.alert-error{background:var(--rose-50);border-color:#f6c9cb;color:#a3232a}
.alert-warning{background:var(--amber-50);border-color:#f3dba2;color:#7d5600}
.alert-info{background:var(--cyan-50);border-color:#b7e4ee;color:#0a6a80}
.toast-wrap{position:fixed;right:1rem;bottom:1rem;z-index:3000;display:flex;flex-direction:column;gap:.6rem;max-width:min(92vw,380px)}
.toast{display:flex;gap:.7rem;align-items:flex-start;padding:.85rem 1rem;background:var(--text);color:#fff;border-radius:var(--radius);box-shadow:var(--shadow-lg);font-size:.9rem;animation:toastIn .35s var(--ease)}
.toast.success{background:#0c6e49}.toast.error{background:#b3282d}
.toast.out{opacity:0;transform:translateY(8px);transition:.3s}
@keyframes toastIn{from{opacity:0;transform:translateY(12px) scale(.97)}to{opacity:1;transform:none}}

/* ---------- Tables ---------- */
.table-wrap{width:100%;overflow-x:auto;-webkit-overflow-scrolling:touch}
table.table{width:100%;border-collapse:collapse;font-size:.9rem}
.table th{padding:.75rem 1rem;text-align:left;font-size:.74rem;font-weight:700;letter-spacing:.05em;text-transform:uppercase;color:var(--muted);background:var(--surface-2);border-bottom:1px solid var(--border);white-space:nowrap}
.table td{padding:.8rem 1rem;border-bottom:1px solid var(--border);vertical-align:middle}
.table tbody tr{transition:background .15s}
.table tbody tr:hover{background:#f8f9fe}
.table tbody tr:last-child td{border-bottom:0}
.table .actions{display:flex;gap:.25rem;justify-content:flex-end}
.table .cell-user{display:flex;align-items:center;gap:.7rem;min-width:0}
.table .cell-user strong{display:block;font-weight:650}
.empty{padding:2.5rem 1rem;text-align:center;color:var(--muted)}
.empty .icon{opacity:.5;margin-bottom:.5rem}

/* ---------- Pagination ---------- */
.pagination{display:flex;gap:.35rem;flex-wrap:wrap;align-items:center;justify-content:center;padding:1rem}
.page-link{min-width:36px;height:36px;padding:0 .6rem;display:inline-grid;place-items:center;border-radius:10px;font-weight:650;font-size:.85rem;color:var(--text-2);background:var(--surface);border:1px solid var(--border);transition:.15s}
a.page-link:hover{border-color:var(--primary);color:var(--primary);background:var(--primary-50)}
.page-link.is-active{background:var(--grad-primary);color:#fff;border-color:transparent;box-shadow:0 4px 10px rgba(52,69,214,.3)}
.page-link.is-disabled{opacity:.45}.page-gap{color:var(--muted);padding:0 .2rem}

/* ---------- Modal ---------- */
.modal{position:fixed;inset:0;z-index:2000;display:none;align-items:center;justify-content:center;padding:1rem}
.modal.is-open{display:flex}
.modal-backdrop{position:absolute;inset:0;background:rgba(15,27,61,.5);backdrop-filter:blur(3px);animation:fade .2s}
.modal-dialog{position:relative;width:min(640px,100%);max-height:calc(100vh - 2rem);display:flex;flex-direction:column;background:var(--surface);border-radius:var(--radius-xl);box-shadow:var(--shadow-lg);animation:pop .3s var(--ease)}
.modal-dialog.wide{width:min(860px,100%)}
.modal-head{display:flex;align-items:center;justify-content:space-between;padding:1.1rem 1.4rem;border-bottom:1px solid var(--border)}
.modal-head h2{margin:0;font-size:1.15rem}
.modal-body{padding:1.4rem;overflow-y:auto}
.modal-foot{display:flex;justify-content:flex-end;gap:.6rem;padding:1rem 1.4rem;border-top:1px solid var(--border);flex-wrap:wrap}
@keyframes fade{from{opacity:0}to{opacity:1}}
@keyframes pop{from{opacity:0;transform:translateY(14px) scale(.97)}to{opacity:1;transform:none}}

/* ---------- Dropdown ---------- */
.dropdown{position:relative}
.dropdown-menu{position:absolute;right:0;top:calc(100% + 8px);min-width:220px;background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);box-shadow:var(--shadow-md);padding:.4rem;opacity:0;visibility:hidden;transform:translateY(-6px);transition:.18s var(--ease);z-index:900}
.dropdown.is-open .dropdown-menu{opacity:1;visibility:visible;transform:none}
.dropdown-item{display:flex;align-items:center;gap:.65rem;width:100%;padding:.6rem .75rem;border:0;background:none;border-radius:9px;font:600 .88rem var(--font);color:var(--text-2);cursor:pointer;text-align:left}
.dropdown-item:hover{background:var(--surface-2);color:var(--text)}

/* ---------- Skeleton ---------- */
.skeleton{position:relative;overflow:hidden;background:var(--surface-2);border-radius:8px;min-height:1em}
.skeleton::after{content:"";position:absolute;inset:0;background:linear-gradient(90deg,transparent,rgba(255,255,255,.7),transparent);transform:translateX(-100%);animation:shimmer 1.3s infinite}
@keyframes shimmer{to{transform:translateX(100%)}}

/* ---------- Entrance + motion ---------- */
.reveal{animation:rise .55s var(--ease) both}
@keyframes rise{from{opacity:0;transform:translateY(14px)}to{opacity:1;transform:none}}
.stagger>*{animation:rise .55s var(--ease) both}
.stagger>*:nth-child(2){animation-delay:.05s}.stagger>*:nth-child(3){animation-delay:.1s}.stagger>*:nth-child(4){animation-delay:.15s}
.stagger>*:nth-child(5){animation-delay:.2s}.stagger>*:nth-child(6){animation-delay:.25s}
@media (prefers-reduced-motion:reduce){*,*::before,*::after{animation-duration:.001ms!important;animation-iteration-count:1!important;transition-duration:.001ms!important;scroll-behavior:auto!important}}

/* ---------- Utilities ---------- */
.flex{display:flex}.items-center{align-items:center}.between{justify-content:space-between}.wrap{flex-wrap:wrap}.gap-1{gap:.5rem}.gap-2{gap:1rem}.grow{flex:1}
.mt-1{margin-top:.5rem}.mt-2{margin-top:1rem}.mt-3{margin-top:1.5rem}.mb-0{margin-bottom:0}.mb-1{margin-bottom:.5rem}.mb-2{margin-bottom:1rem}.mb-3{margin-bottom:1.5rem}
.hidden{display:none!important}
.progress{height:8px;border-radius:99px;background:var(--surface-2);overflow:hidden}.progress>span{display:block;height:100%;border-radius:99px;background:var(--grad-primary)}
.progress.ok>span{background:linear-gradient(90deg,#19b87c,#0e8f5f)}.progress.warn>span{background:linear-gradient(90deg,#f6b73c,#e39500)}.progress.bad>span{background:linear-gradient(90deg,#ee5a5f,#d63a40)}