/* Course Platform — design system
   Two skins in one sheet:
     .admin  merchant side, Shopify-admin adjacent (neutral, dense, calm)
     .learn  student side, brandable via --brand set per shop
*/

:root {
    --bg:        #f6f6f7;
    --surface:   #ffffff;
    --surface-2: #fafbfb;
    --border:    #e1e3e5;
    --border-2:  #c9cccf;
    --text:      #202223;
    --text-2:    #6d7175;
    --text-3:    #8c9196;
    --accent:    #2c6ecb;
    --accent-dk: #1f5199;
    --success:   #008060;
    --success-bg:#e3f1df;
    --warn:      #b98900;
    --warn-bg:   #fff5ea;
    --danger:    #d72c0d;
    --danger-bg: #fef1f0;
    --brand:     #4b3f72;
    --radius:    10px;
    --radius-sm: 7px;
    --shadow:    0 1px 0 rgba(22,29,37,.05), 0 1px 3px rgba(22,29,37,.08);
    --shadow-lg: 0 4px 16px rgba(22,29,37,.12);
    --mono: ui-monospace, SFMono-Regular, "SF Mono", Menlo, monospace;
}

* { box-sizing: border-box; }

body {
    margin: 0;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Inter, Roboto, sans-serif;
    font-size: 14px;
    line-height: 1.5;
    color: var(--text);
    background: var(--bg);
    -webkit-font-smoothing: antialiased;
}

a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }
h1, h2, h3, h4 { margin: 0; font-weight: 650; letter-spacing: -.01em; }
h1 { font-size: 20px; }
h2 { font-size: 16px; }
h3 { font-size: 14px; }
p  { margin: 0 0 10px; }

/* ---------------------------------------------------------------- chrome */

.topbar {
    background: #1a1a1a;
    color: #fff;
    padding: 0 20px;
    height: 52px;
    display: flex;
    align-items: center;
    gap: 22px;
    position: sticky;
    top: 0;
    z-index: 50;
}
.topbar .logo {
    font-weight: 700;
    font-size: 15px;
    color: #fff;
    letter-spacing: -.02em;
    display: flex;
    align-items: center;
    gap: 8px;
}
.topbar .logo .dot {
    width: 18px; height: 18px; border-radius: 5px;
    background: linear-gradient(135deg, #7b61ff, #4b3f72);
    display: inline-block;
}
.topbar nav { display: flex; gap: 4px; margin-left: 10px; }
.topbar nav a {
    color: #c9cccf; padding: 6px 11px; border-radius: 7px; font-weight: 500;
}
.topbar nav a:hover { background: #2e2e2e; color: #fff; text-decoration: none; }
.topbar nav a.on { background: #383838; color: #fff; }
.topbar .spacer { flex: 1; }
.topbar .shopname { color: #8c9196; font-size: 13px; }
.topbar .view-store {
    border: 1px solid #4a4a4a; padding: 5px 12px; border-radius: 7px;
    color: #e3e3e3; font-size: 13px;
}
.topbar .view-store:hover { background: #2e2e2e; text-decoration: none; }

.wrap { max-width: 1080px; margin: 0 auto; padding: 22px 20px 80px; }
.wrap.narrow { max-width: 760px; }
.wrap.wide { max-width: 1240px; }

.pagehead {
    display: flex; align-items: flex-start; gap: 14px;
    margin-bottom: 18px; flex-wrap: wrap;
}
.pagehead .grow { flex: 1; min-width: 220px; }
.pagehead .sub { color: var(--text-2); font-size: 13px; margin-top: 3px; }
.backlink { color: var(--text-2); font-size: 13px; display: inline-block; margin-bottom: 8px; }

/* ---------------------------------------------------------------- cards */

.card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    margin-bottom: 16px;
}
.card > .card-head {
    padding: 13px 16px;
    border-bottom: 1px solid var(--border);
    display: flex; align-items: center; gap: 10px;
}
.card > .card-head .grow { flex: 1; }
.card > .card-body { padding: 16px; }
.card > .card-body.tight { padding: 0; }

.grid { display: grid; gap: 16px; }
.grid.c2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid.c3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid.c4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }
.grid.side { grid-template-columns: minmax(0,1fr) 320px; align-items: start; }

@media (max-width: 900px) {
    .grid.c3, .grid.c4, .grid.side { grid-template-columns: minmax(0, 1fr); }
}
@media (max-width: 640px) {
    .grid.c2 { grid-template-columns: minmax(0, 1fr); }
    .wrap { padding: 16px 14px 60px; }
}

/* ---------------------------------------------------------------- stats */

.stat {
    background: var(--surface); border: 1px solid var(--border);
    border-radius: var(--radius); padding: 14px 16px; box-shadow: var(--shadow);
}
.stat .n { font-size: 26px; font-weight: 700; letter-spacing: -.02em; }
.stat .l { color: var(--text-2); font-size: 12px; text-transform: uppercase;
           letter-spacing: .04em; font-weight: 600; margin-top: 2px; }

/* ---------------------------------------------------------------- buttons */

.btn {
    display: inline-flex; align-items: center; justify-content: center; gap: 6px;
    padding: 7px 14px; border-radius: var(--radius-sm);
    border: 1px solid var(--border-2);
    background: linear-gradient(180deg, #fff, #f6f6f7);
    color: var(--text); font-size: 13px; font-weight: 600; cursor: pointer;
    font-family: inherit; line-height: 1.4;
}
.btn:hover { background: #f1f2f3; text-decoration: none; }
.btn.primary {
    background: linear-gradient(180deg, #2c6ecb, #1f5199);
    border-color: #1f5199; color: #fff;
}
.btn.primary:hover { background: #1f5199; }
.btn.dark {
    background: linear-gradient(180deg, #3a3a3a, #1a1a1a);
    border-color: #1a1a1a; color: #fff;
}
.btn.danger { color: var(--danger); border-color: #e0b3ac; background: #fff; }
.btn.danger:hover { background: var(--danger-bg); }
.btn.sm { padding: 4px 9px; font-size: 12px; }
.btn.block { width: 100%; }
.btn:disabled { opacity: .5; cursor: not-allowed; }

.btn-row { display: flex; gap: 8px; flex-wrap: wrap; align-items: center; }

/* ---------------------------------------------------------------- forms */

label.f { display: block; margin-bottom: 12px; }
label.f > span.lbl {
    display: block; font-weight: 600; font-size: 13px; margin-bottom: 4px;
}
label.f > span.hint { display: block; color: var(--text-3); font-size: 12px; margin-top: 3px; }

input[type=text], input[type=number], input[type=email], input[type=url],
input[type=color], select, textarea {
    width: 100%; padding: 7px 10px; font-size: 13px; font-family: inherit;
    border: 1px solid var(--border-2); border-radius: var(--radius-sm);
    background: #fff; color: var(--text);
}
input:focus, select:focus, textarea:focus {
    outline: 2px solid var(--accent); outline-offset: -1px; border-color: var(--accent);
}
textarea { min-height: 90px; resize: vertical; line-height: 1.55; }
textarea.tall { min-height: 200px; }
input[type=color] { height: 34px; padding: 3px; }

.check { display: flex; align-items: flex-start; gap: 8px; margin-bottom: 10px; }
.check input { margin-top: 2px; }
.check .lbl { font-weight: 600; font-size: 13px; }
.check .hint { color: var(--text-3); font-size: 12px; }

.inline-form { display: flex; gap: 8px; flex-wrap: wrap; align-items: flex-end; }
.inline-form > * { flex: 0 0 auto; }
.inline-form .grow { flex: 1 1 180px; }

fieldset { border: 0; padding: 0; margin: 0 0 18px; }
fieldset legend {
    font-weight: 700; font-size: 12px; text-transform: uppercase;
    letter-spacing: .05em; color: var(--text-2); padding: 0 0 8px;
}

/* ---------------------------------------------------------------- tables */

table.t { width: 100%; border-collapse: collapse; font-size: 13px; }
table.t th {
    text-align: left; font-size: 11px; text-transform: uppercase; letter-spacing: .05em;
    color: var(--text-2); padding: 9px 16px; border-bottom: 1px solid var(--border);
    background: var(--surface-2);
}
table.t td { padding: 11px 16px; border-bottom: 1px solid var(--border); vertical-align: middle; }
table.t tr:last-child td { border-bottom: 0; }
table.t tr:hover td { background: var(--surface-2); }

/* ---------------------------------------------------------------- badges */

.badge {
    display: inline-block; padding: 2px 8px; border-radius: 20px;
    font-size: 11px; font-weight: 650; letter-spacing: .01em;
    background: #e4e5e7; color: #3d3f42;
}
.badge.green  { background: var(--success-bg); color: #0b6b53; }
.badge.yellow { background: var(--warn-bg);    color: #8a6116; }
.badge.red    { background: var(--danger-bg);  color: #a3200b; }
.badge.blue   { background: #e0f0ff;           color: #1f5199; }
.badge.purple { background: #efe8ff;           color: #4b3f72; }

.kind {
    display: inline-flex; align-items: center; justify-content: center;
    width: 26px; height: 26px; border-radius: 7px; flex: 0 0 auto;
    font-size: 13px; background: #eef0f2;
}
.kind.video    { background: #e0f0ff; }
.kind.text     { background: #eceef0; }
.kind.pdf      { background: #fdeceb; }
.kind.quiz     { background: #efe8ff; }
.kind.audio    { background: #e3f1df; }
.kind.download { background: #fff5ea; }

/* ---------------------------------------------------------------- builder */

.builder { display: grid; gap: 14px; }

.module {
    background: var(--surface); border: 1px solid var(--border);
    border-radius: var(--radius); box-shadow: var(--shadow); overflow: hidden;
}
.module.dragging { opacity: .45; }
.module-head {
    display: flex; align-items: center; gap: 10px;
    padding: 11px 14px; background: var(--surface-2);
    border-bottom: 1px solid var(--border);
}
.module-head .grip { cursor: grab; color: var(--text-3); font-size: 15px; line-height: 1; }
.module-head .mtitle { font-weight: 650; font-size: 14px; flex: 1; }
.module-head .meta { color: var(--text-3); font-size: 12px; }

.lesson-list { list-style: none; margin: 0; padding: 6px; min-height: 12px; }
.lesson-list.drop-hover { background: #eef4fc; }
.lesson-row {
    display: flex; align-items: center; gap: 10px;
    padding: 8px 10px; border-radius: var(--radius-sm);
    background: #fff; border: 1px solid transparent;
}
.lesson-row:hover { background: var(--surface-2); border-color: var(--border); }
.lesson-row.dragging { opacity: .4; }
.lesson-row .grip { cursor: grab; color: var(--text-3); font-size: 14px; line-height: 1; }
.lesson-row .name { flex: 1; font-weight: 500; color: var(--text); min-width: 0; }
.lesson-row .name a { color: inherit; }
.lesson-row .name .sub { color: var(--text-3); font-size: 12px; font-weight: 400; }
.lesson-row .tags { display: flex; gap: 5px; flex-wrap: wrap; }

.module-foot {
    padding: 8px 12px 12px; display: flex; gap: 6px; flex-wrap: wrap;
    border-top: 1px dashed var(--border);
}
.addbtn {
    border: 1px dashed var(--border-2); background: #fff; color: var(--text-2);
    padding: 5px 10px; border-radius: var(--radius-sm); font-size: 12px;
    font-weight: 600; cursor: pointer; font-family: inherit;
}
.addbtn:hover { border-color: var(--accent); color: var(--accent); background: #f7fbff; }

.empty {
    text-align: center; padding: 40px 20px; color: var(--text-2);
}
.empty .big { font-size: 32px; margin-bottom: 8px; }
.empty h3 { margin-bottom: 5px; color: var(--text); }

/* ---------------------------------------------------------------- tabs */

.tabs { display: flex; gap: 2px; border-bottom: 1px solid var(--border); margin-bottom: 18px; }
.tabs a {
    padding: 9px 14px; color: var(--text-2); font-weight: 600; font-size: 13px;
    border-bottom: 2px solid transparent; margin-bottom: -1px;
}
.tabs a:hover { color: var(--text); text-decoration: none; }
.tabs a.on { color: var(--accent); border-bottom-color: var(--accent); }

/* ---------------------------------------------------------------- progress */

.bar { height: 6px; background: #e4e5e7; border-radius: 20px; overflow: hidden; }
.bar > i { display: block; height: 100%; background: var(--success); border-radius: 20px; }
.bar.brand > i { background: var(--brand); }
.bar.lg { height: 9px; }

/* ---------------------------------------------------------------- notices */

.notice {
    padding: 11px 14px; border-radius: var(--radius-sm); font-size: 13px;
    border: 1px solid; margin-bottom: 14px;
}
.notice.info  { background: #eef4fc; border-color: #b9d5f5; color: #1f4c85; }
.notice.warn  { background: var(--warn-bg); border-color: #f0d399; color: #7a5610; }
.notice.good  { background: var(--success-bg); border-color: #a7d8bf; color: #0b6b53; }
.notice.bad   { background: var(--danger-bg); border-color: #f0b8b0; color: #96200c; }

code, pre { font-family: var(--mono); font-size: 12px; }
pre {
    background: #1a1a1a; color: #e3e3e3; padding: 12px 14px;
    border-radius: var(--radius-sm); overflow-x: auto;
}
code.inline { background: #eceef0; padding: 1px 5px; border-radius: 4px; color: #3d3f42; }

/* ================================================================ STUDENT */

body.learn { background: #fbfbfc; }

.learn-bar {
    background: var(--brand); color: #fff; padding: 0 22px; height: 58px;
    display: flex; align-items: center; gap: 18px; position: sticky; top: 0; z-index: 40;
}
.learn-bar .brandname { font-weight: 700; font-size: 16px; color: #fff; letter-spacing: -.01em; }
.learn-bar .spacer { flex: 1; }
.learn-bar a { color: rgba(255,255,255,.85); font-weight: 500; }
.learn-bar a:hover { color: #fff; text-decoration: none; }
.learn-bar select {
    width: auto; background: rgba(255,255,255,.14); border-color: rgba(255,255,255,.3);
    color: #fff; font-size: 12px; padding: 5px 8px;
}
.learn-bar select option { color: #202223; }

.hero {
    background: linear-gradient(135deg, var(--brand), #2b2340);
    color: #fff; padding: 40px 22px;
}
.hero .inner { max-width: 1080px; margin: 0 auto; }
.hero h1 { font-size: 30px; letter-spacing: -.02em; margin-bottom: 6px; }
.hero p { color: rgba(255,255,255,.82); max-width: 620px; font-size: 15px; }

.course-grid { display: grid; gap: 18px; grid-template-columns: repeat(auto-fill, minmax(270px, 1fr)); }
.course-card {
    background: #fff; border: 1px solid var(--border); border-radius: 12px;
    overflow: hidden; box-shadow: var(--shadow); display: flex; flex-direction: column;
}
.course-card:hover { box-shadow: var(--shadow-lg); }
.course-card .cover {
    height: 128px; background: linear-gradient(135deg, var(--brand), #6b5b95);
    display: flex; align-items: center; justify-content: center;
    color: rgba(255,255,255,.9); font-size: 34px;
}
.course-card .cover img { width: 100%; height: 100%; object-fit: cover; }
.course-card .body { padding: 14px 15px; flex: 1; display: flex; flex-direction: column; gap: 7px; }
.course-card .body h3 { font-size: 15px; }
.course-card .body .desc { color: var(--text-2); font-size: 13px; flex: 1; }
.course-card .body .foot { display: flex; align-items: center; gap: 8px; }

.lesson-nav { list-style: none; margin: 0; padding: 0; }
.lesson-nav .mod {
    font-size: 11px; text-transform: uppercase; letter-spacing: .05em; font-weight: 700;
    color: var(--text-3); padding: 14px 14px 6px;
}
.lesson-nav a, .lesson-nav .locked {
    display: flex; align-items: center; gap: 9px; padding: 8px 14px;
    color: var(--text); border-left: 3px solid transparent; font-size: 13px;
}
.lesson-nav a:hover { background: var(--surface-2); text-decoration: none; }
.lesson-nav a.on { background: #f2effa; border-left-color: var(--brand); font-weight: 600; }
.lesson-nav .locked { color: var(--text-3); }
.lesson-nav .tick { width: 16px; flex: 0 0 auto; text-align: center; font-size: 12px; }
.lesson-nav .tick.done { color: var(--success); }

.player {
    background: #000; border-radius: 10px; overflow: hidden; margin-bottom: 18px;
    aspect-ratio: 16 / 9; display: flex; align-items: center; justify-content: center;
}
.player iframe, .player video { width: 100%; height: 100%; border: 0; display: block; }
.player .ph { color: #8c9196; font-size: 13px; text-align: center; padding: 20px; }

.prose { font-size: 15px; line-height: 1.7; color: #2f3133; }
.prose p { margin: 0 0 14px; }

.quiz-q {
    border: 1px solid var(--border); border-radius: var(--radius-sm);
    padding: 14px; margin-bottom: 12px; background: #fff;
}
.quiz-q .p { font-weight: 600; margin-bottom: 9px; }
.quiz-opt {
    display: flex; align-items: flex-start; gap: 9px; padding: 7px 9px;
    border-radius: 6px; cursor: pointer;
}
.quiz-opt:hover { background: var(--surface-2); }

.cert {
    background: #fff; border: 10px double var(--brand); border-radius: 6px;
    padding: 48px 40px; text-align: center; max-width: 720px; margin: 0 auto;
}
.cert .k { font-size: 11px; letter-spacing: .28em; text-transform: uppercase; color: var(--text-2); }
.cert h1 { font-size: 30px; margin: 14px 0 6px; color: var(--brand); }
.cert .who { font-size: 24px; font-weight: 600; margin: 22px 0 6px; }
.cert .serial { font-family: var(--mono); font-size: 11px; color: var(--text-3); margin-top: 26px; }

.post {
    border: 1px solid var(--border); border-radius: var(--radius-sm);
    padding: 13px 15px; margin-bottom: 11px; background: #fff;
}
.post .who { font-weight: 650; font-size: 13px; }
.post .when { color: var(--text-3); font-size: 12px; }
.post .body { margin-top: 6px; font-size: 14px; }
.post .replies { margin: 11px 0 0 18px; padding-left: 13px; border-left: 2px solid var(--border); }

@media (max-width: 900px) {
    .learn-shell { grid-template-columns: minmax(0, 1fr) !important; }
    .learn-side { order: 2; }
}