:root {
    --bg: #eef4f6;
    --bg-soft: #f7fafb;
    --panel: rgba(255, 255, 255, 0.9);
    --panel-strong: #ffffff;
    --line: #dce6ea;
    --line-strong: #c8d6dd;
    --text: #17303d;
    --muted: #637884;
    --primary: #0c8e74;
    --primary-strong: #076452;
    --secondary: #295fda;
    --danger: #b84c4c;
    --soft-green: #dcf5ec;
    --soft-blue: #e7f0ff;
    --soft-amber: #fff2d7;
    --shadow: 0 24px 48px rgba(18, 57, 71, 0.12);
    --radius-xl: 30px;
    --radius-lg: 22px;
    --radius-md: 16px;
    --radius-sm: 12px;
    --font-main: "Source Han Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
}

* {
    box-sizing: border-box;
}

html,
body {
    margin: 0;
    min-height: 100%;
    font-family: var(--font-main);
    color: var(--text);
    background:
        radial-gradient(circle at top left, rgba(41, 95, 218, 0.15), transparent 24%),
        radial-gradient(circle at top right, rgba(12, 142, 116, 0.14), transparent 22%),
        linear-gradient(180deg, #f9fcfd 0%, var(--bg) 100%);
}

body {
    min-height: 100vh;
}

a {
    color: inherit;
    text-decoration: none;
}

button,
input,
select,
textarea {
    font: inherit;
}

code {
    padding: 2px 8px;
    border-radius: 999px;
    background: rgba(41, 95, 218, 0.08);
    color: var(--secondary);
}

.glass-card {
    background: var(--panel);
    border: 1px solid rgba(220, 230, 234, 0.92);
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow);
    backdrop-filter: blur(14px);
}

.flash-stack {
    position: fixed;
    top: 16px;
    right: 16px;
    z-index: 1000;
    display: grid;
    gap: 10px;
}

.flash {
    padding: 12px 18px;
    border-radius: 999px;
    box-shadow: var(--shadow);
    font-size: 14px;
    background: #f5fbff;
    border: 1px solid #dbeaf4;
}

.flash-error {
    background: #fff1f0;
    border-color: #f4d2d0;
    color: #9b3934;
}

.flash-success {
    background: #effcf6;
    border-color: #cfeede;
    color: #1b7f59;
}

.hero-chip,
.section-tag {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 8px 14px;
    border-radius: 999px;
    background: var(--soft-green);
    color: var(--primary-strong);
    font-size: 13px;
    font-weight: 800;
    letter-spacing: 0.04em;
}

.auth-shell {
    min-height: 100vh;
    display: grid;
    grid-template-columns: 1.15fr 0.85fr;
    gap: 24px;
    padding: 28px;
}

.admin-auth-shell {
    grid-template-columns: 1fr 0.78fr;
}

.auth-hero,
.auth-panel {
    padding: 34px;
}

.auth-hero h1,
.topbar h1,
.admin-brand h1 {
    margin: 18px 0 12px;
    font-size: clamp(34px, 3.8vw, 52px);
    line-height: 1.04;
}

.hero-copy,
.subtle-copy,
.card-heading p,
.panel-heading p,
.status-row span,
.info-tile p,
.feature-list,
.student-list-item span,
.student-list-item em,
.simple-table th,
.toggle-row p {
    color: var(--muted);
}

.hero-grid {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 14px;
    margin-top: 24px;
}

.info-tile,
.student-card,
.focus-card,
.metric-card,
.status-card,
.content-block,
.table-card,
.section-box,
.log-entry,
.empty-state {
    background: linear-gradient(180deg, #ffffff 0%, #f8fbfc 100%);
    border: 1px solid #e1eaee;
    border-radius: var(--radius-lg);
}

.info-tile,
.status-card,
.empty-state {
    padding: 20px;
}

.info-tile span,
.info-tile strong {
    display: block;
}

.info-tile strong {
    margin: 8px 0;
    font-size: 20px;
}

.info-tile.accent {
    background: linear-gradient(180deg, #f3f7ff 0%, #ffffff 100%);
}

.feature-list {
    margin: 24px 0 0;
    padding-left: 18px;
    line-height: 1.9;
}

.panel-heading,
.card-heading {
    margin-bottom: 18px;
}

.panel-heading h2,
.card-heading h2,
.focus-card h3 {
    margin: 12px 0 8px;
    font-size: 30px;
}

.stack-form {
    display: grid;
    gap: 16px;
}

.field {
    display: grid;
    gap: 8px;
}

.field span,
.toggle-row strong {
    font-size: 14px;
    font-weight: 800;
}

.field input,
.field select,
.field textarea,
.inline-input-row select,
.inline-input-row input {
    width: 100%;
    border: 1px solid var(--line-strong);
    border-radius: var(--radius-md);
    padding: 13px 15px;
    background: #ffffff;
    color: var(--text);
    outline: none;
    transition: border-color 0.18s ease, box-shadow 0.18s ease;
}

.field textarea {
    resize: vertical;
    min-height: 120px;
}

.field input:focus,
.field select:focus,
.field textarea:focus,
.inline-input-row input:focus,
.inline-input-row select:focus {
    border-color: rgba(41, 95, 218, 0.5);
    box-shadow: 0 0 0 4px rgba(41, 95, 218, 0.12);
}

.primary-btn,
.ghost-btn,
.ghost-mini,
.button-like {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    border: none;
    border-radius: 999px;
    cursor: pointer;
    transition: transform 0.16s ease, box-shadow 0.16s ease, opacity 0.16s ease;
}

.primary-btn,
.ghost-btn,
.button-like {
    padding: 14px 22px;
    font-weight: 800;
}

.primary-btn {
    background: linear-gradient(135deg, var(--primary), #11a384);
    color: #ffffff;
    box-shadow: 0 16px 28px rgba(12, 142, 116, 0.24);
}

.ghost-btn,
.ghost-mini {
    background: var(--panel-strong);
    color: var(--text);
    border: 1px solid var(--line);
}

.ghost-mini {
    padding: 8px 12px;
    font-size: 13px;
    font-weight: 700;
}

.ghost-mini.danger {
    color: var(--danger);
}

.outline-link,
.button-like {
    border: 1px dashed var(--line-strong);
    color: var(--secondary);
    padding: 12px 18px;
    border-radius: 999px;
    font-weight: 700;
    background: rgba(255, 255, 255, 0.72);
}

.primary-btn:hover,
.ghost-btn:hover,
.ghost-mini:hover,
.outline-link:hover,
.button-like:hover,
.student-list-item:hover,
.nav-link:hover {
    transform: translateY(-1px);
}

.full-width {
    width: 100%;
}

.table-card {
    overflow: hidden;
}

.table-title {
    padding: 16px 18px;
    font-weight: 800;
    background: linear-gradient(90deg, var(--soft-green), rgba(255, 255, 255, 0.55));
}

.simple-table {
    width: 100%;
    border-collapse: collapse;
}

.simple-table th,
.simple-table td {
    padding: 14px 16px;
    text-align: left;
    border-top: 1px solid #edf2f4;
    vertical-align: top;
}

.simple-table th {
    font-size: 13px;
    font-weight: 800;
    letter-spacing: 0.03em;
    background: #fbfcfd;
}

.app-shell,
.admin-shell {
    min-height: 100vh;
    padding: 18px;
}

.topbar,
.admin-topbar {
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    gap: 18px;
    padding: 24px 28px;
    margin-bottom: 18px;
}

.workspace-grid {
    display: grid;
    grid-template-columns: 360px minmax(0, 1fr);
    gap: 18px;
    align-items: start;
}

.sidebar-panel {
    position: sticky;
    top: 18px;
    padding: 20px;
}

.student-card {
    padding: 22px;
}

.student-card h2,
.admin-brand h1 {
    font-size: 30px;
}

.meta-pills {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin: 18px 0;
}

.meta-pills span {
    padding: 8px 12px;
    border-radius: 999px;
    background: var(--soft-blue);
    color: var(--secondary);
    font-weight: 700;
    font-size: 13px;
}

.metric-grid {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 12px;
    margin: 16px 0;
}

.metric-card {
    padding: 16px;
}

.metric-card span {
    display: block;
    margin-bottom: 8px;
    color: var(--muted);
    font-size: 13px;
}

.metric-card strong {
    font-size: 24px;
}

.metric-card.wide {
    grid-column: 1 / -1;
}

.focus-card {
    padding: 20px;
}

.content-stack,
.ai-layout {
    display: grid;
    gap: 18px;
}

.content-panel,
.list-panel,
.form-panel {
    padding: 24px;
}

.content-block,
.preformatted {
    white-space: pre-wrap;
    line-height: 1.8;
}

.content-block {
    padding: 22px;
}

.chat-log,
.log-stack {
    display: grid;
    gap: 14px;
    margin: 18px 0;
}

.bubble,
.log-entry {
    padding: 16px 18px;
    border-radius: var(--radius-lg);
    border: 1px solid #dde7eb;
    background: #ffffff;
}

.bubble-user,
.log-entry-user {
    background: var(--soft-blue);
}

.bubble-assistant,
.log-entry-assistant {
    background: var(--soft-green);
}

.bubble-meta {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
    margin-bottom: 10px;
    font-size: 13px;
}

.admin-shell {
    display: grid;
    grid-template-columns: 300px minmax(0, 1fr);
    gap: 18px;
}

.admin-sidebar {
    position: sticky;
    top: 18px;
    align-self: start;
    padding: 22px;
}

.admin-brand p {
    margin: 12px 0 0;
    color: var(--muted);
}

.admin-nav {
    display: grid;
    gap: 10px;
    margin: 22px 0;
}

.nav-link {
    padding: 14px 16px;
    border-radius: var(--radius-md);
    background: rgba(255, 255, 255, 0.7);
    border: 1px solid var(--line);
    font-weight: 700;
}

.nav-link.active {
    background: linear-gradient(135deg, rgba(12, 142, 116, 0.14), rgba(41, 95, 218, 0.12));
    border-color: rgba(41, 95, 218, 0.2);
    color: var(--primary-strong);
}

.status-card {
    display: grid;
    gap: 12px;
    margin: 18px 0;
}

.status-row {
    display: flex;
    justify-content: space-between;
    gap: 12px;
}

.status-column {
    flex-direction: column;
}

.admin-main {
    min-width: 0;
}

.summary-strip {
    display: grid;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 14px;
    width: 100%;
}

.summary-strip article {
    padding: 14px 16px;
    border-radius: var(--radius-md);
    background: #ffffff;
    border: 1px solid #e3eaee;
}

.summary-strip span {
    display: block;
    color: var(--muted);
    font-size: 13px;
    margin-bottom: 8px;
}

.summary-strip strong {
    font-size: 28px;
}

.admin-content-grid {
    display: grid;
    grid-template-columns: 320px minmax(0, 1fr);
    gap: 18px;
}

.student-list {
    display: grid;
    gap: 10px;
    max-height: calc(100vh - 320px);
    overflow: auto;
    padding-right: 4px;
}

.student-list-item {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
    padding: 14px 16px;
    border-radius: var(--radius-md);
    background: #ffffff;
    border: 1px solid var(--line);
}

.student-list-item strong,
.student-list-item span,
.student-list-item em {
    display: block;
}

.student-list-item strong {
    margin-bottom: 4px;
}

.student-list-item.active {
    background: linear-gradient(135deg, rgba(12, 142, 116, 0.14), rgba(41, 95, 218, 0.12));
    border-color: rgba(12, 142, 116, 0.3);
}

.form-grid-two {
    grid-template-columns: repeat(2, minmax(0, 1fr));
}

.field-wide {
    grid-column: 1 / -1;
}

.form-actions,
.inline-form,
.table-actions,
.inline-input-row,
.wrap-actions {
    display: flex;
    gap: 12px;
}

.inline-form,
.wrap-actions {
    flex-wrap: wrap;
    align-items: end;
}

.inline-input-row {
    align-items: stretch;
}

.inline-input-row select {
    width: 46%;
}

.inline-input-row input {
    width: 54%;
}

.section-box {
    padding: 18px;
    margin-bottom: 18px;
}

.muted-box {
    background: linear-gradient(180deg, #f8fbff 0%, #ffffff 100%);
}

.status-banner {
    margin-top: 16px;
    padding: 14px 16px;
    border-radius: var(--radius-md);
    background: var(--soft-blue);
    color: var(--secondary);
    font-weight: 700;
}

.status-banner.is-error {
    background: #fff0ef;
    color: var(--danger);
}

.toggle-row {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 16px;
    padding: 18px;
    border-radius: var(--radius-lg);
    background: linear-gradient(180deg, #ffffff 0%, #f8fbfc 100%);
    border: 1px solid #e1eaee;
}

.toggle-row input[type="checkbox"] {
    width: 22px;
    height: 22px;
    accent-color: var(--primary);
}

.button-like {
    border-style: dashed;
}

.empty-state {
    display: grid;
    place-items: center;
    min-height: 240px;
    text-align: center;
}

.empty-state h2 {
    margin-bottom: 10px;
}

@media (max-width: 1280px) {
    .auth-shell,
    .admin-shell,
    .workspace-grid,
    .admin-content-grid {
        grid-template-columns: 1fr;
    }

    .sidebar-panel,
    .admin-sidebar {
        position: static;
    }

    .summary-strip {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }

    .student-list {
        max-height: none;
    }
}

@media (max-width: 860px) {
    .auth-shell,
    .app-shell,
    .admin-shell {
        padding: 14px;
    }

    .auth-hero,
    .auth-panel,
    .topbar,
    .admin-topbar,
    .sidebar-panel,
    .admin-sidebar,
    .content-panel,
    .list-panel,
    .form-panel {
        padding: 18px;
    }

    .hero-grid,
    .metric-grid,
    .summary-strip,
    .form-grid-two {
        grid-template-columns: 1fr;
    }

    .topbar,
    .admin-topbar,
    .toggle-row {
        flex-direction: column;
        align-items: stretch;
    }

    .inline-input-row,
    .form-actions,
    .inline-form,
    .table-actions {
        flex-direction: column;
    }

    .inline-input-row select,
    .inline-input-row input {
        width: 100%;
    }
}