/* Flat UI panel system: neutral cards, buttons, and classroom layout.
   Replaces the former 3D effect layer. Class names are kept for compatibility. */

/* Cards */
.three-d-card {
    border-radius: 10px;
    border: 1px solid var(--line, #dbe3ea);
    box-shadow: 0 1px 2px rgba(16, 32, 50, .05);
}
.three-d-card:hover { box-shadow: 0 4px 12px rgba(16, 32, 50, .08); }

.three-d-layer { display: none; }

/* Dashboard stat tiles */
.three-d-tile {
    background: var(--paper, #ffffff);
    border: 1px solid var(--line, #dbe3ea);
    border-radius: 10px;
    padding: 22px;
    display: flex;
    flex-direction: column;
    gap: 8px;
    text-decoration: none;
}
.three-d-tile:hover { border-color: #c0cdd8; box-shadow: 0 4px 12px rgba(16, 32, 50, .06); }
.three-d-tile i { font-size: 22px; color: var(--navy, #102b4e); }
.three-d-tile strong { font-size: 32px; }
.three-d-tile span { color: var(--muted, #667085); font-size: 13px; }
a.three-d-tile { text-decoration: none; color: inherit; }

/* Buttons */
.btn--3d { box-shadow: 0 1px 2px rgba(16, 32, 50, .08); }
.btn--3d:active { transform: translateY(1px); box-shadow: none; }

/* Classroom cards */
.classroom-card-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
    gap: 18px;
    margin-top: 16px;
}
.classroom-card {
    position: relative;
    display: block;
    background: var(--paper, #fff);
    border: 1px solid var(--line, #dbe3ea);
    border-radius: 10px;
    overflow: hidden;
    color: inherit;
    transition: box-shadow .2s ease;
}
.classroom-card:hover { box-shadow: 0 6px 18px rgba(16, 32, 50, .1); }
.classroom-card__banner {
    height: 110px;
    background:
        linear-gradient(180deg, rgba(8, 22, 38, .12) 0%, rgba(8, 22, 38, .58) 100%),
        url('../images/hero-pages.png') center / cover no-repeat,
        linear-gradient(135deg, var(--banner, #102b4e), #16345e);
    position: relative;
    overflow: hidden;
}
.classroom-card__body { padding: 18px 20px 22px; }
.classroom-card__body h3 { margin: 6px 0; }
.classroom-card__body small { color: var(--muted, #667085); }

/* Classroom banner */
.classroom-shell { --banner: #102b4e; }
.classroom-banner {
    position: relative;
    padding: 28px clamp(18px, 4vw, 56px);
    color: #fff;
    background: url('../images/hero-pages.png') center / cover no-repeat, linear-gradient(135deg, var(--banner), #16345e);
    overflow: hidden;
    border-bottom: 1px solid rgba(255, 255, 255, .08);
    grid-column: 1 / -1;
}
.classroom-banner__bg {
    position: absolute;
    inset: 0;
    background:
        linear-gradient(100deg, rgba(8, 22, 38, .78) 0%, rgba(16, 43, 78, .42) 100%),
        radial-gradient(circle at 80% 20%, rgba(255, 255, 255, .06), transparent 55%);
    pointer-events: none;
}
.classroom-banner__content { position: relative; z-index: 1; max-width: 720px; }
.classroom-banner__content h1 { margin: 6px 0 12px; font-size: clamp(22px, 3.4vw, 30px); }
.classroom-banner__meta { display: flex; flex-wrap: wrap; gap: 14px; color: rgba(255, 255, 255, .85); font-size: 14px; }
.classroom-banner__actions { position: relative; z-index: 1; display: flex; gap: 8px; flex-wrap: wrap; margin-top: 18px; }
.classroom-code {
    background: rgba(255, 255, 255, .16);
    padding: 4px 10px;
    border-radius: 999px;
    font-weight: 700;
    letter-spacing: 1px;
}
.classroom-code-big {
    font-size: 26px;
    font-weight: 800;
    letter-spacing: 4px;
    background: rgba(255, 255, 255, .16);
    padding: 10px 16px;
    border-radius: 10px;
    display: inline-block;
    font-family: 'SF Mono', 'Cascadia Code', 'Fira Code', monospace;
}

/* Classroom tabs */
.classroom-tabs {
    display: flex;
    gap: 4px;
    padding: 12px clamp(18px, 4vw, 56px);
    background: var(--paper, #fff);
    border-bottom: 1px solid var(--line, #dbe3ea);
    grid-column: 1 / -1;
}
.classroom-tabs a {
    padding: 8px 14px;
    border-radius: 8px;
    color: var(--ink, #102032);
    font-weight: 600;
    transition: background .15s ease;
}
.classroom-tabs a:hover { background: #edf3f7; }
.classroom-tabs a.active { background: var(--navy, #102b4e); color: #fff; }

.classroom-workspace { padding: 22px clamp(18px, 4vw, 56px); grid-column: 1 / -1; }

.classroom-grid {
    display: grid;
    grid-template-columns: minmax(0, 2fr) minmax(0, 1fr);
    gap: 22px;
}
@media (max-width: 900px) {
    .classroom-grid { grid-template-columns: 1fr; }
}

.stream-card {
    background: var(--paper, #fff);
    border: 1px solid var(--line, #dbe3ea);
    border-radius: 10px;
    padding: 18px 20px;
    margin-bottom: 14px;
}
.stream-card header { display: flex; align-items: center; gap: 8px; margin-bottom: 6px; color: var(--muted, #667085); font-size: 13px; }
.stream-card header strong { color: var(--ink, #102032); }
.stream-card header i { font-size: 22px; }

.classroom-aside { display: flex; flex-direction: column; gap: 16px; }
.aside-list { list-style: none; padding: 0; margin: 0; }
.aside-list li { padding: 10px 0; border-bottom: 1px solid var(--line, #dbe3ea); }
.aside-list li:last-child { border-bottom: 0; }
.aside-list a { font-weight: 600; color: var(--ink, #102032); }
.aside-list a:hover { color: var(--navy, #102b4e); }
.aside-list small { display: block; color: var(--muted, #667085); font-size: 12px; margin-top: 2px; }

.classwork-list { display: flex; flex-direction: column; gap: 12px; margin-top: 14px; }
.classwork-card {
    display: flex;
    gap: 14px;
    padding: 18px 20px;
    background: var(--paper, #fff);
    border: 1px solid var(--line, #dbe3ea);
    border-radius: 10px;
    color: inherit;
}
.classwork-card__icon {
    width: 52px; height: 52px; border-radius: 10px;
    display: flex; align-items: center; justify-content: center;
    background: #102b4e;
    color: #fff; font-size: 22px; flex-shrink: 0;
}
.classwork-card__icon--assignment { background: #102b4e; }
.classwork-card__icon--material { background: #102b4e; }
.classwork-card__icon--question { background: #102b4e; }
.classwork-card__body h3 { margin: 0 0 4px; }
.classwork-card__body p { margin: 0; color: var(--muted, #667085); }
.classwork-card__body small { display: block; color: var(--muted, #667085); margin-top: 6px; font-size: 12px; }

.classwork-detail {
    background: var(--paper, #fff);
    border: 1px solid var(--line, #dbe3ea);
    border-radius: 10px;
    padding: 28px;
}
.badge { display: inline-block; padding: 4px 12px; border-radius: 999px; font-size: 12px; font-weight: 700; letter-spacing: .3px; }
.badge--assignment { background: rgba(16, 43, 78, .08); color: #102b4e; }
.badge--material { background: rgba(217, 163, 33, .15); color: #b4831a; }
.badge--question { background: rgba(16, 43, 78, .1); color: #102b4e; }

.file-list { list-style: none; padding: 0; margin: 0; }
.file-list li { padding: 8px 0; display: flex; gap: 8px; align-items: center; }

.rubric-block { border: 1px dashed var(--line, #dbe3ea); border-radius: 10px; padding: 14px; margin-top: 14px; background: #fafbfc; }
.rubric-block legend { padding: 0 8px; font-weight: 700; }
.rubric-rows { display: flex; flex-direction: column; gap: 8px; margin: 8px 0; }
.rubric-row { display: grid; grid-template-columns: 2fr 1fr 2fr auto; gap: 8px; align-items: center; }
.rubric-row input { width: 100%; }

.rubric-table { width: 100%; border-collapse: collapse; margin-top: 8px; }
.rubric-table th, .rubric-table td { padding: 10px 8px; border-bottom: 1px solid var(--line, #dbe3ea); text-align: left; vertical-align: top; }
.rubric-table input { width: 90px; }

.people-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(220px, 1fr)); gap: 12px; }
.person-card {
    background: #fafbfc;
    border: 1px solid var(--line, #dbe3ea);
    border-radius: 10px;
    padding: 16px;
    display: flex; flex-direction: column; gap: 4px;
}
.person-card i { font-size: 28px; color: var(--navy, #102b4e); }

.classwork-toolbar { display: flex; align-items: center; justify-content: space-between; gap: 12px; margin-bottom: 16px; }

.people-layout { max-width: 860px; }
.people-layout h2 { margin: 0 0 8px; }
.people-layout > .people-main > .panel { margin-top: 16px; }

.rubric-total {
    background: var(--paper, #fff);
    border: 1px solid var(--line, #dbe3ea);
    padding: 10px 16px;
    border-radius: 10px;
    font-size: 14px;
}
.rubric-total strong { font-size: 22px; color: var(--navy, #102b4e); }

/* Admin modal */
.admin-modal { position: fixed; inset: 0; z-index: 80; display: flex; align-items: center; justify-content: center; padding: 20px; }
.admin-modal[hidden] { display: none; }
.admin-modal__backdrop { position: absolute; inset: 0; background: rgba(8, 22, 38, .72); }
.admin-modal__panel {
    position: relative;
    width: min(420px, calc(100% - 32px));
    max-height: calc(100vh - 40px);
    overflow-y: auto;
    background: var(--paper, #fff);
    border: 1px solid var(--line, #dbe3ea);
    border-radius: 14px;
    padding: 28px;
    box-shadow: 0 18px 48px rgba(8, 22, 38, .35);
}
.admin-modal__close { position: absolute; top: 14px; right: 14px; background: transparent; border: 0; cursor: pointer; font-size: 18px; color: var(--muted, #667085); }
.admin-modal__hint { font-size: 12px; color: var(--muted, #667085); margin-top: -8px; }
body.is-modal-open { overflow: hidden; }

.secret-card { position: relative; max-width: 480px; margin: 60px auto; padding: 28px; border-radius: 14px; }
.secret-card__inner { position: relative; z-index: 1; }

.workspace__head-actions { display: flex; gap: 8px; flex-wrap: wrap; }

/* Sidebar logout button */
.sidebar-logout { padding: 0; margin: 0; margin-top: auto; }
.sidebar-logout button {
    width: 100%;
    background: transparent;
    border: 0;
    padding: 10px 14px;
    display: flex;
    align-items: center;
    gap: 12px;
    color: rgba(255, 255, 255, .55);
    text-align: left;
    cursor: pointer;
    font: inherit;
    font-size: 14px;
    border-radius: 8px;
    transition: background .15s ease, color .15s ease;
}
.sidebar-logout button:hover { background: rgba(255, 255, 255, .08); color: rgba(255, 255, 255, .85); }

/* Join card visual */
.join-card__inner { display: grid; grid-template-columns: 1fr 220px; gap: 24px; align-items: stretch; }
.join-card__visual { min-height: 200px; background: linear-gradient(160deg, rgba(16, 43, 78, .3) 0%, rgba(8, 22, 38, .62) 100%), url('../images/hero-pages.png') center / cover no-repeat, linear-gradient(135deg, #102b4e, #16345e); border-radius: 12px; }
@media (max-width: 700px) { .join-card__inner { grid-template-columns: 1fr; } .join-card__visual { min-height: 140px; } }

/* Home stats */
.counter-row { display: flex; gap: 32px; flex-wrap: wrap; align-items: baseline; }
.counter-cell { display: flex; flex-direction: column; gap: 2px; padding: 6px 18px 6px 0; }
.counter-cell strong { font-size: clamp(30px, 4vw, 44px); font-weight: 800; color: #d9a321; line-height: 1; white-space: nowrap; }
.counter-cell small { color: rgba(255,255,255,.72); font-size: 13px; letter-spacing: 1px; text-transform: uppercase; }

/* Home CTA band */
.cta-3d {
    position: relative;
    border-radius: 16px;
    padding: clamp(24px, 4vw, 48px);
    background: #102b4e;
    color: #fff;
    overflow: hidden;
    box-shadow: 0 10px 24px rgba(16, 32, 50, .16);
}
.cta-3d::before {
    content: "";
    position: absolute;
    inset: 0;
    background: radial-gradient(circle at 20% 30%, rgba(255, 255, 255, .05), transparent 50%);
    pointer-events: none;
}
.cta-3d > * { position: relative; z-index: 1; }

/* Removed 3D elements (kept as inert for markup compatibility) */
.three-d-canvas, .hero-orb, .scroll-cue, .three-d-visual, .floating-shape,
.three-d-canvas-mount { display: none; }

@media (max-width: 620px) {
    .admin-modal__panel { padding: 22px 18px; }
    .secret-card { margin: 28px auto; padding: 24px 18px; }
}