/* === GCOJ Style — Flat, sharp corners (graphcity_blog style) === */

/* HarmonyOS Sans SC — self-hosted (same as graphcity_blog) */
@font-face {
    font-family: 'HarmonyOS Sans SC';
    src: url('HarmonyOS_Sans_SC_Regular.woff2') format('woff2'),
         url('HarmonyOS_Sans_SC_Regular.ttf') format('truetype');
    font-weight: 400;
    font-display: swap;
    font-style: normal;
}
@font-face {
    font-family: 'HarmonyOS Sans SC';
    src: url('HarmonyOS_Sans_SC_Black.woff2') format('woff2'),
         url('HarmonyOS_Sans_SC_Black.ttf') format('truetype');
    font-weight: 900;
    font-display: swap;
    font-style: normal;
}

:root {
    --primary: #6366f1;
    --primary-dark: #4f46e5;
    --bg: #f8f8f8;
    --card-bg: #ffffff;
    --text: #1e293b;
    --text-secondary: #64748b;
    --border: #e2e8f0;
    --code-bg: #f6f8fa;
    --code-text: #24292e;
    --accent: #818cf8;
    --danger: #ef4444;
    --success: #22c55e;
    --warning: #f59e0b;
    --shadow: 0 1px 3px rgba(0,0,0,.08);
}

/* Reset */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
body {
    font-family: 'HarmonyOS Sans SC', -apple-system, BlinkMacSystemFont, 'Segoe UI', system-ui, sans-serif;
    background: var(--bg);
    color: var(--text);
    line-height: 1.6;
    min-height: 100vh;
}
a { color: var(--primary); text-decoration: none; }
a:hover { text-decoration: underline; }
code, pre { font-family: 'JetBrains Mono', 'Fira Code', monospace; }

/* Navbar */
.navbar {
    display: flex; justify-content: space-between; align-items: center;
    padding: 0 24px; height: 56px;
    background: var(--card-bg); border-bottom: 1px solid var(--border);
    box-shadow: var(--shadow); position: sticky; top: 0; z-index: 100;
}
.nav-left, .nav-right { display: flex; align-items: center; gap: 16px; }
.brand { font-size: 1.25rem; font-weight: 900; color: var(--primary); }
.nav-link { color: var(--text-secondary); font-size: .9rem; padding: 4px 8px; transition: color .15s; }
.nav-link:hover { color: var(--primary); text-decoration: none; }
.admin-link { color: var(--danger) !important; }
.nav-user { font-weight: 600; color: var(--text); }
.nav-role { font-size: .75rem; background: var(--accent); color: #fff; padding: 2px 8px; text-transform: uppercase; }

/* Messages */
.messages { padding: 8px 24px 0; }
.message { padding: 10px 16px; margin-bottom: 8px; font-size: .9rem; border-left: 4px solid; }
.message-success { background: #dcfce7; color: #166534; border-color: var(--success); }
.message-error { background: #fef2f2; color: #991b1b; border-color: var(--danger); }
.message-warning { background: #fffbeb; color: #92400e; border-color: var(--warning); }

/* Main */
.main-content { max-width: 1100px; margin: 0 auto; padding: 24px; }
h2 { font-size: 1.5rem; margin-bottom: 24px; color: var(--text); border-left: 4px solid var(--primary); padding-left: 16px; font-weight: 900; }
.problem-header {
    display: flex; align-items: center; gap: 0;
    margin-bottom: 24px; padding: 16px 0;
    border-bottom: 1px solid var(--border);
}
.prob-id-lg {
    font-family: 'HarmonyOS Sans SC', -apple-system, BlinkMacSystemFont, sans-serif;
    font-weight: 900; font-size: 2.5rem; color: var(--primary);
    min-width: 60px; text-align: center; line-height: 1;
}
.prob-divider-lg {
    width: 2px; height: 48px; background: var(--accent); opacity: 0.6;
    margin: 0 24px; flex-shrink: 0;
}
.prob-title-group { display: flex; flex-direction: column; }
.prob-title-lg { font-size: 1.4rem; font-weight: 900; }
h3 { font-size: 1.15rem; margin: 12px 0 8px; }

/* Auth */
.auth-container { max-width: 400px; margin: 60px auto; background: var(--card-bg); padding: 32px; border: 1px solid var(--border); box-shadow: var(--shadow); }
.auth-container h2 { border-left: 4px solid var(--primary); padding-left: 16px; margin-bottom: 24px; }
.auth-form { display: flex; flex-direction: column; gap: 12px; }
.auth-form label { font-weight: 600; font-size: .9rem; }
.auth-form input, .auth-form select, .auth-form textarea {
    font-family: inherit;
    padding: 10px 12px; border: 1px solid var(--border); font-size: .95rem;
    background: var(--bg); color: var(--text); transition: border-color .15s;
}
.auth-form input:focus, .auth-form select:focus, .auth-form textarea:focus {
    outline: none; border-color: var(--primary); box-shadow: 0 0 0 3px rgba(99,102,241,.15);
}
.auth-switch { text-align: center; margin-top: 16px; font-size: .9rem; color: var(--text-secondary); }

/* Buttons */
.btn {
    font-family: inherit;
    display: inline-block; padding: 10px 20px; border: 1px solid var(--border);
    background: var(--card-bg); color: var(--text); font-size: .9rem;
    cursor: pointer; text-align: center; transition: all .15s;
}
.btn:hover { background: var(--bg); text-decoration: none; }
.btn-primary { background: var(--primary); color: #fff; border-color: var(--primary); }
.btn-primary:hover { background: var(--primary-dark); }
.btn-danger { background: var(--danger); color: #fff; border-color: var(--danger); }
.btn-danger:hover { background: #dc2626; border-color: #dc2626; }
.btn-sm { padding: 4px 12px; font-size: .8rem; }

/* Problem grid */
.problem-grid { display: flex; flex-direction: column; gap: 1px; background: var(--border); border: 1px solid var(--border); }
.problem-card {
    display: flex; align-items: center; gap: 0; padding: 16px 20px;
    background: var(--card-bg); border-left: 4px solid transparent;
    transition: border-color .15s, background .15s;
}
.problem-card:hover { border-left-color: var(--primary); background: #f8fafc; text-decoration: none; }
.prob-id {
    font-family: 'HarmonyOS Sans SC', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    font-weight: 900; font-size: 1.1rem; color: var(--primary);
    min-width: 48px; text-align: center;
}
.prob-divider {
    width: 2px; height: 28px; background: var(--accent); margin: 0 20px; flex-shrink: 0;
    opacity: 0.6;
}
.prob-title { font-weight: 600; flex: 1; color: var(--text); }
.tag { font-family: inherit; background: var(--bg); color: var(--text-secondary); padding: 2px 8px; font-size: .75rem; border: 1px solid var(--border); }

/* Problem detail — graphcity_blog article-page style */
.detail-header { margin-bottom: 32px; }
.detail-header-body { border-left: 4px solid var(--primary); padding-left: 24px; }
.detail-header h1 { font-size: 96px; color: var(--primary); font-weight: 900; line-height: 1; margin: -0.06em 0 16px; text-wrap: balance; }
.detail-meta { display: flex; gap: 24px; font-size: .95rem; color: var(--text); margin-top: 0; font-weight: 700; }
.detail-tags { display: flex; gap: 6px; margin-top: 10px; flex-wrap: wrap; }
.detail-tags .tag { font-family: inherit; background: var(--bg); color: var(--text-secondary); padding: 3px 10px; font-size: .8rem; border: 1px solid var(--border); }

.detail-layout { display: flex; gap: 32px; align-items: flex-start; }
.detail-layout article { flex: 1; min-width: 0; background: var(--card-bg); padding: 32px 40px; }
.detail-sidebar { position: sticky; top: 72px; width: 260px; flex-shrink: 0; }

.submit-card { background: var(--card-bg); border: 1px solid var(--border); padding: 24px; }
.submit-card h3 { font-size: 16px; font-weight: 900; color: var(--text); margin-bottom: 16px; border-left: 3px solid var(--primary); padding-left: 10px; }
.submit-card label { display: block; font-weight: 600; font-size: .85rem; margin: 12px 0 4px; color: var(--text-secondary); }
.submit-card select {
    width: 100%; padding: 10px 12px; border: 1px solid var(--border);
    font-size: .9rem; background: var(--bg); color: var(--text);
    font-family: inherit; cursor: pointer;
    transition: border-color .15s;
}
.submit-card select:focus { outline: none; border-color: var(--primary); }
.submit-card input[type=file] {
    width: 100%; padding: 8px; border: 1px dashed var(--border);
    font-size: .85rem; background: var(--bg); color: var(--text-secondary);
    font-family: inherit; cursor: pointer;
}
.submit-card input[type=file]::file-selector-button {
    font-family: inherit; font-size: .8rem; padding: 6px 14px;
    margin-right: 10px; border: none;
    background: var(--primary); color: #fff; cursor: pointer;
    transition: background .15s;
}
.submit-card input[type=file]::file-selector-button:hover {
    background: var(--primary-dark);
}
.submit-card textarea {
    width: 100%; padding: 12px; border: 1px solid var(--border);
    font-size: 13px; background: var(--code-bg); color: var(--code-text);
    font-family: 'JetBrains Mono', 'Fira Code', monospace;
    resize: vertical; min-height: 180px; line-height: 1.5;
    transition: border-color .15s;
}
.submit-card textarea:focus { outline: none; border-color: var(--primary); }
.submit-card textarea::placeholder { color: #959da5; }
.submit-btn { width: 100%; margin-top: 16px; padding: 12px; font-size: .95rem; font-weight: 700; }

.article-body { font-size: 16px; }
.article-body h2 { margin-top: 32px; margin-bottom: 12px; border: none !important; font-size: 24px; color: #444; font-weight: 700; padding-left: 0 !important; }
.article-body h3 { margin-top: 24px; font-size: 20px; }
.article-body p { margin: 12px 0; }
.article-body ul, .article-body ol { margin: 8px 0 8px 24px; }
.article-body li { margin: 4px 0; }
.article-body pre { margin: 12px 0; }
.article-body code { font-family: 'JetBrains Mono', monospace; font-size: 14px; }
.article-body :not(pre) > code { background: #f0f0f0; padding: 2px 6px; color: #c0392b; }
.article-body .highlight { border-radius: 0; }
.article-body .highlight pre { padding: 20px 24px; }
.article-body table { width: 100%; border-collapse: collapse; margin: 16px 0; }
.article-body th { background: var(--primary); color: #fff; padding: 10px 14px; text-align: left; }
.article-body td { padding: 8px 14px; border-bottom: 1px solid #e0e0e0; }
.article-body blockquote { border-left: 4px solid var(--primary); padding: 8px 16px; margin: 16px 0; background: #f5f7fa; color: #555; }
.article-body img { max-width: 100%; }

/* Submissions */
.submission-table { width: 100%; border-collapse: collapse; margin: 12px 0; }
.submission-table th, .submission-table td {
    padding: 10px 12px; text-align: left; border-bottom: 1px solid var(--border);
}
.submission-table th { font-size: .85rem; color: var(--text-secondary); font-weight: 600; }
.submission-table tbody tr:hover { background: var(--bg); }

/* Result page */
.result-banner { padding: 16px 20px; font-size: 1.1rem; font-weight: 600; margin: 12px 0; border-left: 6px solid; }
.result-ac { background: #dcfce7; color: #166534; border-color: var(--success); }
.result-partial, .result-partial-wa { background: #fef2f2; color: #991b1b; border-color: var(--danger); }
.result-partial-tle, .result-partial-mle { background: #eff6ff; color: #1e40af; border-color: #3b82f6; }
.result-partial-re { background: #f5f3ff; color: #6b21a8; border-color: #7c3aed; }
.result-partial-ce { background: #fefce8; color: #854d0e; border-color: #eab308; }
.result-fail { background: #fef2f2; color: #991b1b; border-color: var(--danger); }
.result-actions { display: flex; gap: 12px; margin-top: 16px; }

.tc-grid {
    display: grid;
    grid-template-columns: repeat(8, 1fr);
    gap: 10px;
    margin: 12px 0;
    max-width: 100%;
}
.tc-card {
    background: var(--card-bg); border: 1px solid var(--border);
    padding: 10px 8px; text-align: center;
    display: flex; flex-direction: column; justify-content: center; gap: 6px;
    aspect-ratio: 1;
    min-width: 0;
}
.tc-num { font-size: .75rem; color: var(--text-secondary); }
.tc-result { font-size: 1.8rem; font-weight: 900; }
.tc-result .badge { font-size: inherit; }
.tc-stats { display: flex; flex-direction: column; gap: 2px; font-size: .75rem; color: var(--text-secondary); }
.tc-ac { border-left: 3px solid var(--success); }
.tc-wa { border-left: 3px solid var(--danger); }
.tc-tle, .tc-mle { border-left: 3px solid #3b82f6; }
.tc-re { border-left: 3px solid #7c3aed; }
.tc-ce { border-left: 3px solid #eab308; }
.sub-meta-row {
    display: flex; justify-content: space-between; align-items: center;
    margin: 8px 0 20px; color: var(--text-secondary); font-size: .95rem;
}
.polling-msg { text-align: center; padding: 40px; }
.polling-msg .hint { color: var(--text-secondary); font-size: .85rem; margin-top: 8px; }

/* Badges */
.badge { font-size: .8rem; font-weight: 700; padding: 2px 10px; text-transform: uppercase; }
.badge-ac, .badge-accepted, .badge-success { background: #dcfce7; color: #166534; }
.badge-wa, .badge-wrong_answer { background: #fef2f2; color: #991b1b; }
.badge-tle, .badge-time_limit_exceeded, .badge-mle, .badge-memory_limit_exceeded { background: #dbeafe; color: #1e40af; }
.badge-re, .badge-runtime_error { background: #f3e8ff; color: #6b21a8; }
.badge-ce, .badge-compile_error { background: #fef9c3; color: #854d0e; }
.badge-pending { background: #f1f5f9; color: #475569; }
.badge-admin { background: #fef2f2; color: #991b1b; }
.badge-user { background: #f0fdf4; color: #166534; }
.badge-banned { background: #f1f5f9; color: #9ca3af; text-decoration: line-through; }

/* Difficulty */
.difficulty { font-size: .8rem; padding: 2px 8px; }
.difficulty-beginner { background: #f0fdf4; color: #166534; }
.difficulty-easy { background: #dcfce7; color: #16a34a; }
.difficulty-medium { background: #fef9c3; color: #a16207; }
.difficulty-hard { background: #fef2f2; color: #dc2626; }
.difficulty-expert { background: #f3e8ff; color: #7c3aed; }

/* Admin */
.admin-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(280px, 1fr)); gap: 16px; }
.admin-card { background: var(--card-bg); border: 1px solid var(--border); padding: 20px; box-shadow: var(--shadow); }
.admin-card h3 { margin-bottom: 8px; }
.admin-card p { font-size: .9rem; color: var(--text-secondary); margin-bottom: 12px; }
.filter-form { display: flex; gap: 8px; margin-bottom: 16px; }
.filter-form input { padding: 8px 10px; border: 1px solid var(--border); font-size: .9rem; background: var(--bg); }
.empty { text-align: center; color: var(--text-secondary); padding: 40px; }
.export-json { background: var(--code-bg); color: var(--code-text); padding: 16px; overflow-x: auto; font-size: .8rem; max-height: 600px; overflow-y: auto; }

/* Footer */
.footer { text-align: center; padding: 24px; color: var(--text-secondary); font-size: .85rem; border-top: 1px solid var(--border); margin-top: 40px; }
.theme-dots { display: flex; justify-content: center; gap: 8px; margin-bottom: 12px; }
.dot { width: 20px; height: 20px; cursor: pointer; border: 2px solid transparent; transition: border-color .15s, transform .1s; }
.dot:hover { border-color: var(--text); transform: scale(1.15); }

/* Markdown body */
.markdown-body { line-height: 1.8; }
.markdown-body h1 { font-size: 1.4rem; margin: 16px 0 8px; border-left: 4px solid var(--primary); padding-left: 12px; }
.markdown-body h2 { font-size: 1.25rem; margin: 14px 0 6px; border-left: 3px solid var(--accent); padding-left: 10px; }
.markdown-body h3 { font-size: 1.1rem; margin: 12px 0 4px; }
.markdown-body p { margin: 8px 0; }
.markdown-body ul, .markdown-body ol { margin: 8px 0; padding-left: 24px; }
.markdown-body li { margin: 4px 0; }
.markdown-body table { border-collapse: collapse; width: 100%; margin: 12px 0; }
.markdown-body th, .markdown-body td { border: 1px solid var(--border); padding: 8px 12px; text-align: left; }
.markdown-body th { background: var(--bg); font-weight: 600; }
.markdown-body blockquote { border-left: 4px solid var(--accent); margin: 12px 0; padding: 4px 16px; color: var(--text-secondary); background: var(--bg); }
.markdown-body hr { border: none; border-top: 1px solid var(--border); margin: 16px 0; }
.markdown-body img { max-width: 100%; }

/* Codehilite (GitHub light style) */
.highlight { background: #f6f8fa; color: #24292e; padding: 12px 16px; overflow-x: auto; font-size: .85rem; line-height: 1.5; margin: 8px 0; border: 1px solid var(--border); }
.highlight pre { margin: 0; font-family: 'JetBrains Mono', 'Fira Code', monospace; }
.highlight .hll { background-color: #fffbdd; }
.highlight .c { color: #6a737d; } /* Comment */
.highlight .k { color: #d73a49; } /* Keyword */
.highlight .o { color: #d73a49; } /* Operator */
.highlight .s { color: #032f62; } /* String */
.highlight .n { color: #24292e; } /* Name */
.highlight .p { color: #24292e; } /* Punctuation */
.highlight .m { color: #005cc5; } /* Number */
.highlight .mi { color: #005cc5; }
.highlight .mf { color: #005cc5; }
.highlight .nb { color: #005cc5; } /* Builtin */
.highlight .nc { color: #6f42c1; } /* Class */
.highlight .nf { color: #6f42c1; } /* Function */
.highlight .kd { color: #d73a49; } /* Keyword.Def */
.highlight .kt { color: #d73a49; } /* Keyword.Type */
.highlight .bp { color: #005cc5; } /* Builtin.Pseudo */
.highlight .cm { color: #6a737d; } /* Comment.Multiline */
.highlight .cp { color: #6a737d; } /* Comment.Preproc */
.highlight .c1 { color: #6a737d; } /* Comment.Single */
.highlight .kc { color: #d73a49; } /* Keyword.Constant */
.highlight .kn { color: #d73a49; } /* Keyword.Namespace */
.highlight .kp { color: #d73a49; } /* Keyword.Pseudo */
.highlight .kr { color: #d73a49; } /* Keyword.Reserved */
.highlight .nt { color: #22863a; } /* Name.Tag */
.highlight .nv { color: #e36209; } /* Name.Variable */
.highlight .vc { color: #e36209; } /* Variable.Class */
.highlight .vg { color: #e36209; } /* Variable.Global */
.highlight .vi { color: #e36209; } /* Variable.Instance */

code { background: var(--bg); padding: 1px 6px; font-size: .9em; border: 1px solid var(--border); }
pre code { background: none; padding: 0; border: none; }

pre { position: relative; }
.copy-btn {
    position: absolute; top: 0; right: 0;
    font-size: 12px; padding: 5px 12px;
    color: #586069; background: transparent;
    border: none; cursor: pointer; opacity: 0; transition: opacity .2s;
    font-family: 'HarmonyOS Sans SC', -apple-system, sans-serif;
}
pre:hover .copy-btn { opacity: 1; }
.copy-btn:hover { background: rgba(0,0,0,.08); color: #24292e; }

input[type=file]::file-selector-button {
    font-family: 'HarmonyOS Sans SC', -apple-system, sans-serif;
    font-size: .85rem; padding: 6px 14px; margin-right: 10px;
    border: 1px solid var(--border); background: var(--bg);
    color: var(--text); cursor: pointer;
}
input[type=file]::file-selector-button:hover { border-color: var(--primary); color: var(--primary); }

/* Button font consistency */
button, input[type=submit], .btn {
    font-family: 'HarmonyOS Sans SC', -apple-system, sans-serif;
}

/* Pagination */
.pagination {
    margin-top: 32px;
    margin-bottom: 48px;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 4px;
}
.pagination a,
.pagination span {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-width: 34px;
    height: 34px;
    padding: 0 6px;
    border-radius: 0;
    text-decoration: none;
    font-size: 14px;
    color: var(--text-secondary);
    transition: all 0.15s;
}
.pagination a:hover {
    background: var(--bg);
    color: var(--primary);
    text-decoration: none;
}
.pagination .disabled {
    color: #ccc;
}
.pagination .current-page {
    background: var(--primary);
    color: #fff;
    font-weight: 900;
}
.page-jump {
    display: inline-flex;
    align-items: center;
    margin-left: 12px;
}
.page-jump input {
    width: 48px;
    height: 34px;
    border: 1px solid var(--border);
    text-align: center;
    font-family: inherit;
    font-size: 14px;
    color: var(--text);
    background: var(--card-bg);
}
.page-jump input:focus {
    outline: none;
    border-color: var(--primary);
}
.page-jump button {
    height: 34px;
    padding: 0 12px;
    border: 1px solid var(--primary);
    background: var(--primary);
    color: #fff;
    font-family: inherit;
    font-size: 13px;
    font-weight: 900;
    cursor: pointer;
    margin-left: 4px;
    transition: background 0.15s;
}
.page-jump button:hover {
    background: var(--primary-dark);
    border-color: var(--primary-dark);
}

/* Responsive */
@media (max-width: 768px) {
    .detail-header h1 { font-size: 36px; }
    .detail-header-body { border-left-width: 4px; padding-left: 16px; }
    .detail-layout { flex-direction: column; }
    .detail-sidebar { position: static; width: 100%; }
    .detail-layout article { padding: 20px; }
    .admin-grid { grid-template-columns: 1fr; }
    .navbar { padding: 0 12px; }
    .nav-left, .nav-right { gap: 8px; }
}