/* ClassHub — Campus Editorial
   Direction: warm paper, ink, vermilion accent, restrained borders.
   Keeps existing Bootstrap/Jinja class hooks and light/dark theme support. */
:root{
 --ch-indigo:#c94f32; --ch-fuchsia:#a33d29;
 --ch-grad:linear-gradient(135deg,#d96543,#bd452d);
 --ch-grad-soft:linear-gradient(135deg,rgba(217,101,67,.10),rgba(227,211,185,.22));
 --ch-mesh:radial-gradient(700px 420px at 100% 0%,rgba(217,101,67,.07),transparent 60%);
 --ch-bg:#f5f2ec; --ch-surface:rgba(255,255,255,.8); --ch-surface-solid:#fffdf9;
 --ch-text:#252923; --ch-muted:#73766e; --ch-line:#e4e0d7;
 --ch-shadow:0 8px 24px -18px rgba(37,41,35,.25); --ch-radius:16px; --ch-radius-sm:10px;
 --bs-body-font-family:"DM Sans",system-ui,-apple-system,"Segoe UI",sans-serif;
 --bs-body-bg:var(--ch-bg);--bs-body-color:var(--ch-text);--bs-secondary-color:var(--ch-muted);
 --bs-border-color:var(--ch-line);--bs-link-color:var(--ch-indigo);--bs-link-hover-color:var(--ch-fuchsia);
 --bs-card-bg:var(--ch-surface-solid);--bs-card-border-color:var(--ch-line);
}
[data-bs-theme="dark"]{
 --ch-bg:#171a17;--ch-mesh:radial-gradient(700px 420px at 100% 0%,rgba(217,101,67,.10),transparent 60%);
 --ch-surface:rgba(35,39,34,.9);--ch-surface-solid:#222620;--ch-text:#f0eee7;--ch-muted:#a5a99e;
 --ch-line:#3a3e35;--ch-shadow:0 10px 28px -18px #000;--bs-body-bg:var(--ch-bg);--bs-body-color:var(--ch-text);
 --bs-secondary-color:var(--ch-muted);--bs-border-color:var(--ch-line);--bs-link-color:#f08b6e;
 --bs-link-hover-color:#ffb49d;--bs-card-bg:var(--ch-surface-solid);--bs-card-border-color:var(--ch-line);
}
*{box-sizing:border-box}
html{scroll-behavior:smooth;scroll-padding-top:6rem}
body{font-family:var(--bs-body-font-family);color:var(--ch-text);background:var(--ch-bg);background-image:var(--ch-mesh);background-attachment:fixed;-webkit-font-smoothing:antialiased;line-height:1.6}
::selection{background:rgba(217,101,67,.2)}
h1,h2,h3,h4,h5,h6{font-family:Manrope,"DM Sans",sans-serif;font-weight:800;letter-spacing:-.045em}
a{color:var(--bs-link-color);text-underline-offset:3px}
a:hover{color:var(--bs-link-hover-color)}
:focus-visible{outline:3px solid #e48b70;outline-offset:3px;border-radius:5px}
.skip-link{position:absolute;left:-999px;top:0;z-index:2000;padding:.5rem 1rem;background:var(--ch-surface-solid);color:var(--ch-text)}
.skip-link:focus{left:0}
main.container{max-width:1200px}
main>*{animation:rise .38s ease both}
@keyframes rise{from{opacity:0;transform:translateY(7px)}to{opacity:1;transform:none}}
/* Navigation */
.app-header{position:sticky;top:0;z-index:1030;padding:.7rem 0 0;background:linear-gradient(var(--ch-bg) 75%,transparent)}
.app-nav{background:var(--ch-surface-solid);border:1px solid var(--ch-line);border-radius:14px;box-shadow:0 5px 18px -15px rgba(20,20,20,.35);padding:.55rem .8rem}
.brand{display:inline-flex;align-items:center;gap:.7rem;font-family:Manrope,sans-serif;font-weight:800;font-size:1.12rem;letter-spacing:-.05em;color:var(--ch-text);text-decoration:none;line-height:1.05}
.brand:hover{color:var(--ch-text)}
.brand-mark{display:grid;place-items:center;width:40px;height:40px;border-radius:11px;background:#282d26;color:#fff;font-size:1.15rem;letter-spacing:-.08em}
.brand-mark span{color:#f18b6c}
.brand small{display:block;margin-top:4px;font:700 .55rem "DM Sans",sans-serif;letter-spacing:.13em;color:var(--ch-muted)}
.navbar-toggler{border:1px solid var(--ch-line);border-radius:9px;padding:.45rem .6rem;color:var(--ch-text)}
.navbar-toggler:focus{box-shadow:0 0 0 3px rgba(217,101,67,.15)}
.navbar-toggler-icon{background-image:none!important;width:1.2rem;height:1.2rem;background-color:currentColor;-webkit-mask:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24'%3E%3Cpath d='M3 6h18M3 12h18M3 18h18' fill='none' stroke='%23000' stroke-width='2.4' stroke-linecap='round'/%3E%3C/svg%3E") center/contain no-repeat;mask:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24'%3E%3Cpath d='M3 6h18M3 12h18M3 18h18' fill='none' stroke='%23000' stroke-width='2.4' stroke-linecap='round'/%3E%3C/svg%3E") center/contain no-repeat}
.app-nav .navbar-nav{gap:.1rem;padding:.25rem 0}
.app-nav .nav-link{color:var(--ch-muted);font-weight:700;font-size:.9rem;border-radius:8px;padding:.55rem .75rem;transition:background .18s,color .18s}
.app-nav .nav-link:hover{color:var(--ch-text);background:var(--ch-bg)}
.app-nav .nav-link.active{color:var(--ch-text)!important;background:#f2e4dc;box-shadow:inset 0 -2px #d96543}
[data-bs-theme="dark"] .app-nav .nav-link.active{background:#3b2b25;color:#ffb49d!important}
.nav-tools{display:flex;flex-direction:column;gap:.55rem;padding:.5rem 0}
.search-form{width:100%}
.search-form .form-control{border-radius:9px;padding-left:.85rem;background:var(--ch-bg);border:1px solid var(--ch-line)}
.btn-theme{width:38px;height:38px;padding:0;border-radius:10px;display:inline-grid;place-items:center;background:var(--ch-bg);border:1px solid var(--ch-line);color:var(--ch-text)}.btn-theme .ico{width:19px;height:19px}.btn-theme .ico-sun{display:none}[data-bs-theme=dark] .btn-theme .ico-sun{display:block}[data-bs-theme=dark] .btn-theme .ico-moon{display:none}
@media(min-width:992px){.nav-tools{flex-direction:row;align-items:center;padding:0}.search-form{width:190px}}
/* Editorial home hero */
.hero{position:relative;isolation:isolate;overflow:hidden;padding:clamp(1.6rem,5vw,4.4rem);border-radius:18px;background:#252d25;color:#fff;box-shadow:none;border:1px solid rgba(255,255,255,.06)}
.hero:before{content:"";position:absolute;z-index:-1;width:360px;height:360px;right:-120px;top:-155px;border:1px solid rgba(255,255,255,.14);border-radius:50%;box-shadow:0 0 0 35px rgba(255,255,255,.025),0 0 0 75px rgba(255,255,255,.02)}
.hero:after{content:"";position:absolute;z-index:-1;width:190px;height:190px;right:8%;bottom:-145px;border-radius:50%;background:#d96543;filter:blur(1px);opacity:.85}
.hero-kicker{display:flex;align-items:center;flex-wrap:wrap;gap:.65rem;color:#c6c9bf;font-size:.7rem;font-weight:800;letter-spacing:.14em;margin-bottom:1.8rem}
.hero-kicker-dot{width:7px;height:7px;border-radius:50%;background:#ee8b6d}
.hero-date{padding-left:.7rem;border-left:1px solid #697067;letter-spacing:.02em;font-weight:600}
.hero-title{color:#fff;font-size:clamp(2.3rem,6vw,4.5rem);font-weight:800;line-height:1.02;letter-spacing:-.065em;max-width:760px}
.hero-accent{color:#f18b6c}
.hero-lead{color:#d3d7ce;font-size:1.02rem;max-width:34rem;line-height:1.8}
.hero .btn-light{background:#f5f2ec;border-color:#f5f2ec;color:#282d26}
.hero .btn-outline-light{border-color:#747c71;color:#fff}
.hero .btn-outline-light:hover{background:#fff;color:#252d25}
.hl{background:linear-gradient(transparent 58%,rgba(241,139,108,.4) 0);padding:0 .1em}
.chip{display:inline-flex;align-items:center;gap:.4rem;padding:.35rem .85rem;border-radius:6px;background:rgba(255,255,255,.1);border:1px solid rgba(255,255,255,.18);color:#fff;font-weight:700;font-size:.85rem}
/* Quick links */
.tile{display:flex;flex-direction:column;align-items:flex-start;gap:.75rem;height:100%;padding:1rem .8rem;border-radius:12px;background:var(--ch-surface-solid);border:1px solid var(--ch-line);box-shadow:none;color:var(--ch-text);font-weight:700;font-size:.85rem;text-align:left;text-decoration:none;transition:transform .18s,border-color .18s,background .18s}
.tile:hover{color:var(--ch-text);transform:translateY(-2px);border-color:#d96543;background:var(--ch-surface-solid)}
.tile-ico{display:grid;place-items:center;width:40px;height:40px;border-radius:10px;background:var(--ch-bg);color:var(--ch-indigo)}.tile-ico .ico{width:21px;height:21px}
@media(min-width:768px){.tile{flex-direction:row;align-items:center;gap:.65rem;font-size:.92rem;padding:.9rem}}
/* Content cards */
.card,.stat-card,.assign-card,.file-card{border:1px solid var(--ch-line);border-radius:14px;background:var(--ch-surface-solid);box-shadow:none;overflow:hidden}
.card-header{background:transparent;border-bottom:1px solid var(--ch-line);padding:1.05rem 1.2rem;font-weight:800;letter-spacing:-.02em}
.card-body{padding:1.25rem}
.card-lift{transition:transform .18s,border-color .18s}
.card-lift:hover{transform:translateY(-2px);border-color:#d96543;box-shadow:none}
.list-group{--bs-list-group-bg:transparent;--bs-list-group-border-color:var(--ch-line);--bs-list-group-color:var(--ch-text)}
.list-group-item{padding:1rem 1.2rem;background:transparent}
.list-group-item.bg-light{background:var(--ch-bg)!important}
.today-card{border:1px solid #d96543;background:var(--ch-surface-solid)}
.stat-card{display:flex;flex-direction:column;gap:.35rem;height:100%;padding:1.2rem}
.stat-ico{display:grid;place-items:center;width:38px;height:38px;border-radius:10px;background:var(--ch-bg);color:var(--ch-indigo);margin-bottom:.25rem}.stat-ico .ico{width:20px;height:20px}
.stat-num{font-family:Manrope,sans-serif;font-size:2.65rem;font-weight:800;line-height:1;letter-spacing:-.07em;color:var(--ch-indigo)}
.stat-label{font-weight:800}
.stat-link{margin-top:auto;padding-top:.65rem;font-weight:800;text-decoration:none}
.assign-card{position:relative;margin-bottom:1rem;padding:1.15rem 1.25rem 1.15rem 1.5rem}
.assign-card:before{content:"";position:absolute;left:0;top:0;bottom:0;width:4px;background:#d96543}
.assign-card.is-done{opacity:.7}.assign-card.is-done:before{background:#9ca397}
.file-card{display:flex;flex-direction:column;justify-content:space-between;height:100%;padding:1.15rem}
.eyebrow{font-size:.7rem;font-weight:800;text-transform:uppercase;letter-spacing:.12em;color:var(--ch-muted)}
.file-chip{display:inline-grid;place-items:center;flex-shrink:0;min-width:3.4rem;padding:.35rem .5rem;border-radius:7px;color:#fff;font-size:.72rem;font-weight:800;letter-spacing:.05em;text-transform:uppercase}
.file-pdf{background:#bd4934}.file-doc,.file-docx{background:#456f9e}.file-ppt,.file-pptx{background:#bd653c}.file-xls,.file-xlsx{background:#4e7b59}.file-zip{background:#75668b}.file-png,.file-jpg,.file-jpeg{background:#a64c73}.file-other{background:#73766e}
.meta-pill{display:inline-flex;align-items:center;gap:.3rem;margin:0 .35rem .35rem 0;padding:.25rem .6rem;border-radius:6px;background:var(--ch-bg);color:var(--ch-text);font-size:.78rem;font-weight:700}
/* Buttons */
.btn{border-radius:9px;font-weight:700;padding:.58rem 1rem;transition:transform .15s,box-shadow .18s,background .18s}
.btn:active{transform:scale(.98)}.btn-sm{padding:.4rem .75rem;font-size:.84rem}
.btn-navy{background:#c94f32;border:1px solid #c94f32;color:#fff;box-shadow:none}
.btn-navy:hover,.btn-navy:focus{background:#ad4028;border-color:#ad4028;color:#fff;transform:translateY(-1px)}
.btn-outline-navy{color:var(--ch-indigo);border:1px solid rgba(201,79,50,.45);background:transparent}
.btn-outline-navy:hover{background:var(--ch-indigo);border-color:var(--ch-indigo);color:#fff}
[data-bs-theme="dark"] .btn-outline-navy{color:#f08b6e;border-color:rgba(240,139,110,.45)}
.btn-outline-secondary{border:1px solid var(--ch-line);color:var(--ch-muted);background:transparent}
.btn-outline-secondary:hover{background:var(--ch-bg);color:var(--ch-text);border-color:var(--ch-line)}
.btn-light{color:#252923}
/* Forms, alerts, badges */
.form-label{font-weight:700;font-size:.9rem;margin-bottom:.4rem}
.form-control,.form-select{border-radius:9px;border:1px solid var(--ch-line);background:var(--ch-surface-solid);color:var(--ch-text);padding:.7rem .9rem}
.form-control-sm{padding:.45rem .75rem}
.form-control:focus,.form-select:focus{border-color:#d96543;box-shadow:0 0 0 3px rgba(217,101,67,.13);background:var(--ch-surface-solid);color:var(--ch-text)}
.form-text{color:var(--ch-muted)}.form-check-input:checked{background-color:var(--ch-indigo);border-color:var(--ch-indigo)}
.form-check-input:focus{box-shadow:0 0 0 3px rgba(217,101,67,.15)}.is-invalid{border-color:#dc3545!important}.invalid-feedback{font-weight:600}
.filter-bar{padding:.75rem;border-radius:12px;background:var(--ch-surface-solid);border:1px solid var(--ch-line);box-shadow:none}
.alert{border:1px solid transparent;border-radius:10px;font-weight:600;box-shadow:none}
.alert-info{background:rgba(14,165,233,.1);color:#075985}.alert-warning{background:rgba(245,158,11,.12);color:#92400e}.alert-danger{background:rgba(244,63,94,.1);color:#9f1239}.alert-success{background:rgba(16,185,129,.1);color:#065f46}
[data-bs-theme="dark"] .alert-info{color:#bae6fd}[data-bs-theme="dark"] .alert-warning{color:#fde68a}[data-bs-theme="dark"] .alert-danger{color:#fecdd3}[data-bs-theme="dark"] .alert-success{color:#a7f3d0}
.badge{border-radius:6px;padding:.45em .7em;font-weight:800;letter-spacing:.01em}
.pill-dot{display:inline-block;width:7px;height:7px;border-radius:50%;background:currentColor;margin-right:.4rem;vertical-align:middle}
.is-urgent .pill-dot{animation:pulse 1.6s ease-out infinite}@keyframes pulse{0%{box-shadow:0 0 0 0 rgba(244,63,94,.5)}70%,100%{box-shadow:0 0 0 7px rgba(244,63,94,0)}}
.tag-hot{display:inline-block;padding:.3rem .6rem;border-radius:5px;background:#c94f32;color:#fff;font-weight:800;font-size:.7rem;letter-spacing:.05em;text-transform:uppercase}
/* Tables and admin tabs */
.table-responsive{padding:.25rem .5rem;border-radius:12px;background:var(--ch-surface-solid);border:1px solid var(--ch-line);box-shadow:none}
.table{--bs-table-bg:transparent;--bs-table-color:var(--ch-text);--bs-table-border-color:var(--ch-line);margin-bottom:0}
.table>:not(caption)>*>*{padding:.85rem .75rem}
.table thead th{font-size:.7rem;text-transform:uppercase;letter-spacing:.1em;color:var(--ch-muted);font-weight:800;border-bottom-width:1px}
.table tbody tr:hover>*{background:rgba(217,101,67,.05)}
.admin-tabs{display:flex;gap:.25rem;overflow-x:auto;padding:.3rem;margin-bottom:1.5rem;background:var(--ch-surface-solid);border:1px solid var(--ch-line);border-radius:12px;scrollbar-width:none}
.admin-tabs::-webkit-scrollbar{display:none}
.admin-tab{flex:0 0 auto;padding:.55rem .85rem;border-radius:8px;white-space:nowrap;color:var(--ch-muted);font-weight:700;font-size:.9rem;text-decoration:none;transition:background .18s,color .18s}
.admin-tab:hover{color:var(--ch-text);background:var(--ch-bg)}
.admin-tab.active{background:#282d26;color:#fff;box-shadow:none}
[data-bs-theme="dark"] .admin-tab.active{background:#d96543;color:#fff}
.stat-card .stat-link{color:var(--ch-indigo)}
.pagination .page-link{border:1px solid var(--ch-line);border-radius:8px!important;margin:0 .2rem .4rem;min-width:2.5rem;text-align:center;background:var(--ch-surface-solid);color:var(--ch-text);font-weight:700;box-shadow:none}
.pagination .page-link:hover{background:var(--ch-bg);color:var(--ch-text)}
.pagination .page-item.active .page-link{background:var(--ch-indigo);border-color:var(--ch-indigo);color:#fff}
.pagination .page-item.disabled .page-link{opacity:.5}
/* Page headings, login, footer */
.page-head{margin-bottom:1.5rem}.page-title{font-size:clamp(1.7rem,3.2vw,2.35rem);letter-spacing:-.055em;margin:0 0 .25rem}.page-sub{color:var(--ch-muted);margin:0;font-size:.98rem}
.section-title{display:flex;align-items:center;gap:.5rem;font-size:1.15rem;margin:2.25rem 0 1rem}
.ink{color:var(--ch-text);text-decoration:none}.ink:hover{color:var(--ch-fuchsia)}.pre-line{white-space:pre-line}.min-w-0{min-width:0}.text-navy{color:var(--bs-link-color)!important}.border-navy{border-color:var(--ch-indigo)!important}.bg-navy{background:var(--ch-indigo)!important}
.empty-state{text-align:center;padding:2.5rem 1rem;border-radius:12px;border:1px dashed var(--ch-line);color:var(--ch-muted);font-weight:700;background:var(--ch-surface)}
details summary{cursor:pointer;font-weight:700;color:var(--ch-muted)}
.login-card{max-width:440px;margin:0 auto;padding:2rem;border-radius:16px;background:var(--ch-surface-solid);border:1px solid var(--ch-line);box-shadow:var(--ch-shadow)}
.login-ico{display:grid;place-items:center;width:4.2rem;height:4.2rem;margin:0 auto;border-radius:14px;background:#282d26;color:white}.login-ico .ico{width:30px;height:30px;stroke-width:1.6}
.big-code{font-size:clamp(4.5rem,16vw,7.5rem);font-weight:800;line-height:1;letter-spacing:-.07em;color:var(--ch-indigo)}
.site-footer{margin-top:auto;padding:2rem 0;color:var(--ch-muted);font-size:.85rem;border-top:1px solid var(--ch-line)}
.site-footer a{color:inherit;font-weight:800;text-decoration:none}.site-footer a:hover{color:var(--ch-fuchsia)}
@media(max-width:575px){main.container{padding-top:1.25rem!important}.hero{padding:1.5rem;border-radius:14px}.hero-kicker{margin-bottom:1.3rem}.hero-title{font-size:2.45rem}.card-header{padding:.9rem 1rem}.list-group-item{padding:.85rem 1rem}}
@media(prefers-reduced-motion:reduce){*,*::before,*::after{animation:none!important;transition:none!important;scroll-behavior:auto!important}}

/* Ikon SVG (sprite static/images/icons.svg) */
.ico{width:1.1em;height:1.1em;flex-shrink:0;vertical-align:-.2em;fill:none;stroke:currentColor;stroke-width:1.75;stroke-linecap:round;stroke-linejoin:round}
.ico-sm{width:.95em;height:.95em;vertical-align:-.15em}
.btn .ico{margin-right:.35rem;vertical-align:-.18em}.btn .ico-end{margin:0 0 0 .3rem}
.page-title .ico{width:.8em;height:.8em;margin-right:.4rem;color:var(--ch-indigo);vertical-align:-.05em}
.section-title .ico{width:1.05em;height:1.05em;color:var(--ch-indigo)}
.card-header .ico{margin-right:.4rem;color:var(--ch-indigo)}
.meta-pill .ico,.small .ico,.text-muted .ico{width:1em;height:1em;vertical-align:-.17em;margin-right:.2rem;opacity:.75}
.tag-hot .ico{width:.95em;height:.95em;margin-right:.2rem;vertical-align:-.15em}
.stat-link .ico,.small.fw-bold .ico{width:.95em;height:.95em;margin-left:.2rem;vertical-align:-.15em}
.empty-state .ico{display:block;width:34px;height:34px;margin:0 auto .6rem;opacity:.55}
.admin-tab .ico{width:1em;height:1em;margin-right:.2rem;vertical-align:-.17em}