:root{font-family:system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;background:#0e1829;color:#eef4ff;color-scheme:dark}
*{box-sizing:border-box}body{margin:0}header{border-bottom:1px solid #273a53;padding:16px 22px;background:#111f34;display:flex;justify-content:space-between;align-items:center;flex-wrap:wrap;gap:8px}header a{font-weight:700;font-size:18px;color:#edf4ff;text-decoration:none}
main{max-width:1000px;margin:auto;padding:26px 16px 70px}h1{font-size:26px;margin:8px 0 20px}h2{font-size:19px}h3{font-size:16px}p{color:#c5d4e8;line-height:1.55}.panel{background:#15253c;border:1px solid #2c4260;border-radius:14px;padding:20px;margin:16px 0}.narrow{max-width:470px;margin:30px auto}.grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(240px,1fr));gap:12px}.tile{display:block;text-decoration:none;background:#1a304b;border:1px solid #314765;padding:22px;border-radius:12px;color:#ecf4ff}.tile:hover{border-color:#79b9ff}label{display:block;color:#d7e6f5;margin:11px 0 5px;font-size:14px}input,select{width:100%;padding:11px;background:#0e1d31;border:1px solid #3b5778;border-radius:8px;color:#fff;font-size:15px}input[type=checkbox]{width:auto}button,.btn{display:inline-block;border:none;cursor:pointer;background:#4d9ff4;color:#09213e;font-weight:750;padding:11px 15px;border-radius:9px;text-decoration:none;margin-top:10px}button:hover,.btn:hover{background:#8bc6ff}.muted,small{color:#9eb4d0;font-size:13px}.row{display:flex;flex-wrap:wrap;gap:10px;align-items:center}.row>*{flex:1}.row button{flex:0 0 auto}table{width:100%;border-collapse:collapse;font-size:14px}td,th{padding:11px 8px;text-align:left;border-bottom:1px solid #2f4360;vertical-align:middle}td form{display:inline-block}td button{margin:3px 1px;padding:6px 10px}.danger{background:#b43e4b;color:white}.ok{color:#92ecb0}.bad{color:#ffb8b8}.scroll{overflow:auto}video{width:100%;max-height:75vh;border-radius:12px;background:black}a{color:#91c5ff}.hint{background:#132d3f;border-left:3px solid #6d9fcd;padding:11px 15px;border-radius:6px}.outline{border:1px solid #5e7a9e;background:transparent;color:#d3e7ff}
.player-shell{position:relative;background:#05070c;border-radius:14px;overflow:hidden;min-height:170px}
.player-shell video{display:block;width:100%;max-height:82vh;aspect-ratio:16/9;border-radius:0}
.player-shell:fullscreen{display:flex;justify-content:center;align-items:center;flex-direction:column}
.player-shell:fullscreen video{width:100%;height:100%;max-height:100%;object-fit:contain}
.watermark{position:absolute;z-index:5;pointer-events:none;user-select:none;left:7%;top:10%;opacity:.32;color:white;text-shadow:0 1px 3px black;font-weight:700;font-size:clamp(17px,3vw,37px);white-space:nowrap;transition:left 3s linear,top 3s linear}
.fullscreen{position:absolute;bottom:56px;right:14px;z-index:6;background:#173b64;color:white;opacity:.87;padding:8px;font-size:13px}
.panel hr{border:0;border-top:1px solid #344b66;margin:22px 0}
small{line-height:1.5}
.buttonline{display:flex;align-items:center;gap:5px;flex-wrap:wrap}
.buttonline form{display:inline-block}
.checkrow{display:inline-flex;align-items:center;gap:7px;padding:6px 12px;margin:2px;border:1px solid #405573;border-radius:8px}
.checkrow input{width:auto}
.player-shell .player-controls{position:relative;z-index:10;display:flex;align-items:center;gap:8px;background:#101c31;padding:7px 10px}
.player-shell .player-controls button{margin:0;padding:8px 10px;white-space:nowrap}
.player-shell .player-controls input[type=range]{flex:1;min-width:20px;margin:0;padding:0;height:20px}
.player-shell .player-controls span{white-space:nowrap;font-size:12px}
.player-shell.pseudo-full{position:fixed;inset:0;z-index:10000;border-radius:0;background:black;display:flex;justify-content:center;flex-direction:column}
.player-shell.pseudo-full video{flex:1;width:100%;height:calc(100% - 55px);max-height:calc(100% - 55px)}
.player-shell:fullscreen video{flex:1;width:100%;height:calc(100% - 55px);max-height:calc(100% - 55px)}
@media(max-width:430px){.player-shell .player-controls button{font-size:12px;padding:7px}.player-shell .player-controls span{font-size:10px}}

progress{width:100%;height:8px;accent-color:#62b4ff} .search-form{margin:12px 0 22px}.search-form .row input{flex:3}.search-form .row button{flex:0 0 auto}

.upload-progress{width:100%;height:13px;margin-top:12px}.upload-status{min-height:18px}

/* V01.5.5: unified student login; responsive speed controls. */
.student-login h1{text-align:center;margin-bottom:4px}.student-login>p:first-of-type{text-align:center}
.student-login .login-wide{width:100%;margin-top:14px}.student-login .login-note{font-size:12px;line-height:1.65;margin-top:22px}
.student-login #login-status:empty{display:none}
/* V01.5.11: accessible fine speed control, kept inside the fullscreen shell. */
.player-shell .playback-speed{position:relative;z-index:10;display:flex;align-items:center;gap:9px;background:#101c31;border-top:1px solid #2a3c55;padding:7px 10px}
.player-shell .playback-speed label{margin:0;white-space:nowrap;font-size:12px}
.player-shell .playback-speed input[type=range]{flex:1;min-width:50px;width:auto;margin:0;padding:0;accent-color:#6cb5ff;cursor:pointer}
.player-shell .playback-speed output{font-size:14px;min-width:56px;text-align:center;font-variant-numeric:tabular-nums;white-space:nowrap}
.player-shell .playback-speed button{margin:0;padding:8px 10px;font-size:12px;white-space:nowrap}
.player-shell .playback-speed button:disabled{opacity:.4;cursor:not-allowed}
.player-shell:fullscreen .player-controls,.player-shell:fullscreen .playback-speed,.player-shell.pseudo-full .player-controls,.player-shell.pseudo-full .playback-speed{width:100%;flex-shrink:0}
.player-shell:fullscreen video,.player-shell.pseudo-full video{flex:1 1 0;min-height:0;height:auto;max-height:calc(100% - 135px);object-fit:contain}
@media(max-width:550px){.player-shell .player-controls{flex-wrap:wrap}.player-shell .player-controls input[type=range]{flex-basis:45%;order:1}.player-shell .player-controls #time{order:2}.player-shell .playback-speed{gap:6px;flex-wrap:wrap}.player-shell .playback-speed label{flex:0 0 auto}.player-shell .playback-speed input[type=range]{flex:1 1 36%;order:1}.player-shell .playback-speed output{order:2}.player-shell .playback-speed button{padding:8px;font-size:12px}.player-shell .playback-speed #speed-reset{margin-left:auto}}
@media(max-width:350px){.player-shell .playback-speed label{display:none}.player-shell .playback-speed input[type=range]{flex-basis:32%}}

/* Entrance notice: visual countdown only, not an authentication control. */
.announcement h1{text-align:center}.announcement h2{text-align:center;margin-top:0}.announcement .notice-body{white-space:pre-wrap;background:#0e1d31;border:1px solid #3b5778;border-radius:10px;padding:18px;line-height:1.85;overflow-wrap:anywhere}.announcement #enter-login{display:block;text-align:center}.announcement .enter-disabled{opacity:.5;cursor:not-allowed;pointer-events:none}.announcement .btn:not(.enter-disabled){background:#4d9ff4}

textarea{width:100%;background:#0e1d31;border:1px solid #3b5778;border-radius:8px;color:#fff;font:inherit;padding:12px;resize:vertical}


/* V01.5.12: isolated visual redesign of student login; other pages unchanged. */
.visually-hidden{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap}
body.login-page{background:#061936;color:#f5f8ff;min-height:100vh;min-height:100dvh;overflow-x:hidden}
body.login-page>header{display:none}
body.login-page>main{max-width:none;min-height:100vh;min-height:100dvh;padding:0;position:relative;isolation:isolate;
 background: radial-gradient(ellipse at 50% -15%,rgba(19,98,210,.65),transparent 52%),radial-gradient(circle at 93% 14%,rgba(19,80,166,.34),transparent 27%),linear-gradient(160deg,#0b2c5d 0%,#061832 49%,#071e40 100%)}
body.login-page>main::before{content:"";position:absolute;z-index:-1;pointer-events:none;top:13%;left:-25%;width:150%;height:27%;border-top:2px solid rgba(39,142,255,.45);border-radius:50%;transform:rotate(-5deg);filter:drop-shadow(0 0 9px #187af0)}
body.login-page>main::after{content:"";position:absolute;z-index:-1;pointer-events:none;bottom:0;left:-20%;width:140%;height:15%;border-top:2px solid rgba(53,151,255,.65);border-radius:50%;transform:rotate(-4deg);filter:drop-shadow(0 0 8px #187af0)}
.login-stage{width:min(100%,540px);min-height:100vh;min-height:100dvh;margin:0 auto;padding:clamp(22px,5vh,50px) 18px 22px;display:flex;flex-direction:column;gap:20px}
.login-brand{text-align:center}
.login-brand .login-emblem{display:block;width:clamp(100px,28vw,136px);height:clamp(100px,28vw,136px);object-fit:contain;margin:0 auto 10px;filter:drop-shadow(0 0 12px rgba(70,173,255,.4))}
.login-brand h1{font-size:clamp(27px,6.5vw,38px);letter-spacing:.09em;color:#f5faff;font-weight:800;line-height:1.24;margin:8px auto 12px;text-shadow:0 2px 6px #0d315d}
.login-brand p{color:#a2bce1;font-size:clamp(14px,3.3vw,18px);margin:0;letter-spacing:.05em}
.login-page .student-login{width:100%;max-width:none;margin:0;border-radius:20px;padding:24px 26px 21px;background:linear-gradient(145deg,rgba(15,48,96,.72),rgba(10,35,73,.79));border:1px solid rgba(83,159,251,.39);box-shadow:0 14px 45px rgba(0,6,25,.19)}
.login-page .student-login label{font-size:17px;font-weight:650;margin:16px 0 9px;color:#f1f6ff}
.login-page .student-login label:first-of-type{margin-top:0}
.login-page .student-login input{font-size:16px;padding:14px 15px;min-height:52px;background:rgba(2,20,48,.68);border:1px solid #436894;border-radius:12px;color:white}
.login-page .student-login input::placeholder{color:#839cbf}
.login-page .student-login input:focus-visible{outline:2px solid #5eb4ff;outline-offset:1px}
.login-page .student-login button.login-wide{display:block;width:100%;min-height:53px;margin-top:14px;border-radius:12px;font-size:17px;font-weight:700}
.login-page .student-login #send-sms{border:1.5px solid #4aa7ff;background:rgba(41,108,183,.18);color:#f0f8ff}
.login-page .student-login #verify-login{background:#469fff;color:#092144;box-shadow:0 5px 18px rgba(51,138,248,.2)}
.login-page .student-login .login-note{font-size:12px;line-height:1.65;text-align:center;color:#a6bbd7;margin:18px 0 0}
.login-page .student-login #login-status{font-size:13px;min-height:0}
.login-footer{text-align:center;margin:auto auto 0;padding-top:8px;color:#9db4d6}
.login-footer .login-legal-title{font-size:13px}
.login-footer p{font-size:12px;line-height:1.65;margin:8px auto 22px;color:#8ea9cd}
.login-footer .footer-contact{font-size:14px;line-height:1.7;margin:0 auto 13px;color:#d5e6ff}
.login-footer .footer-contact a{color:inherit;text-decoration:underline;text-underline-offset:3px}
.login-signature{display:flex;align-items:center;gap:13px;justify-content:center;color:#ecce80;letter-spacing:.28em;font-family:serif;font-size:20px;font-weight:650;text-shadow:0 0 7px rgba(255,198,84,.3)}
.login-signature::before,.login-signature::after{content:"";display:block;width:52px;height:1px;background:linear-gradient(90deg,transparent,#d5ab55)}
.login-signature::after{transform:rotate(180deg)}
@media(max-width:420px){.login-stage{gap:18px;padding:24px 17px 18px}.login-page .student-login{padding:21px 20px}.login-page .student-login input{min-height:48px}.login-page .student-login button.login-wide{min-height:49px}.login-brand .login-emblem{width:106px;height:106px}.login-brand h1{font-size:29px}}
@media(max-width:350px){.login-brand h1{font-size:25px}.login-page .student-login{padding:18px 15px}}
/* Keep decorative wave pseudoelements from enlarging the mobile page viewport. */
body.login-page>main{overflow:hidden}


/* V01.5.13: match the entrance notice to the approved login branding. */
body.notice-page{background:#061936;color:#f5f8ff;min-height:100vh;min-height:100dvh;overflow-x:hidden}
body.notice-page>header{display:none}
body.notice-page>main{max-width:none;min-height:100vh;min-height:100dvh;padding:0;position:relative;isolation:isolate;overflow:hidden;background:radial-gradient(ellipse at 50% -15%,rgba(19,98,210,.65),transparent 52%),radial-gradient(circle at 93% 14%,rgba(19,80,166,.34),transparent 27%),linear-gradient(160deg,#0b2c5d 0%,#061832 49%,#071e40 100%)}
body.notice-page>main::before{content:"";position:absolute;z-index:-1;pointer-events:none;top:13%;left:-25%;width:150%;height:27%;border-top:2px solid rgba(39,142,255,.45);border-radius:50%;transform:rotate(-5deg);filter:drop-shadow(0 0 9px #187af0)}
body.notice-page>main::after{content:"";position:absolute;z-index:-1;pointer-events:none;bottom:0;left:-20%;width:140%;height:15%;border-top:2px solid rgba(53,151,255,.65);border-radius:50%;transform:rotate(-4deg);filter:drop-shadow(0 0 8px #187af0)}
.notice-stage{width:min(100%,540px);min-height:100vh;min-height:100dvh;margin:0 auto;padding:clamp(22px,5vh,50px) 18px 24px;display:flex;flex-direction:column;gap:20px}
.notice-page .announcement{width:100%;max-width:none;margin:0;border-radius:20px;padding:24px 26px;background:linear-gradient(145deg,rgba(15,48,96,.72),rgba(10,35,73,.79));border:1px solid rgba(83,159,251,.39);box-shadow:0 14px 45px rgba(0,6,25,.19)}
.notice-page .announcement h2{font-size:21px;margin:0 0 16px;color:#f3f8ff}
.notice-page .announcement .notice-body{background:rgba(2,20,48,.68);border:1px solid #436894;color:#e2efff;font-size:15px;line-height:1.8;max-height:min(42vh,300px);overflow-y:auto;overscroll-behavior:contain}
.notice-page .announcement #enter-login{width:100%;min-height:53px;padding:14px 12px;border-radius:12px;font-size:17px;font-weight:700}
.notice-page .announcement .muted{text-align:center;line-height:1.65}
@media(max-width:420px){.notice-stage{gap:18px;padding:24px 17px 18px}.notice-page .announcement{padding:21px 20px}}
@media(max-width:350px){.notice-page .announcement{padding:18px 15px}}

/* V01.5.14 visitor trial controls */
.trial-login{border-top:1px solid rgba(149,192,255,.3);margin-top:20px;padding-top:14px}
.trial-login h3{margin:0 0 8px;color:#d7eaff}
.trial-status{padding:9px 13px;border:1px solid #467aaf;border-radius:10px;background:#102e53;color:#fff;margin:10px 0}
.trial-status strong{color:#ffe18c;font-variant-numeric:tabular-nums}

/* V01.5.24: scoped admin test-dashboard navigation and reset, other pages unchanged. */
body.admin-page {background:linear-gradient(140deg,#071a35 0%,#0d223e 52%,#101b32 100%)}
body.admin-page > header {padding:11px 24px;background:#08172e;border-color:#1c3860}
body.admin-page > main {max-width:1680px;padding:16px 20px 72px}
.admin-layout {display:grid;grid-template-columns:238px minmax(0,1fr);align-items:start;gap:22px}
.admin-sidebar {background:#0b203d;border:1px solid #28436c;border-radius:16px;padding:20px 13px;position:sticky;top:16px;max-height:calc(100vh - 32px);overflow:auto;box-shadow:0 12px 34px rgba(0,0,0,.15)}
.admin-sidebar-brand {display:flex;align-items:center;gap:11px;padding:4px 10px 18px;font-weight:800;font-size:17px;border-bottom:1px solid #294468}
.admin-sidebar-brand small {display:block;margin-top:5px;font-size:11px;letter-spacing:.03em;font-weight:500}
.admin-brand-mark {background:#2664ab;border-radius:13px;padding:8px 10px;color:white;font-size:22px}
.admin-nav {display:grid;gap:4px;padding-top:17px}
.admin-nav a {text-decoration:none;display:block;color:#c6d9f2;padding:11px 12px;border-radius:10px;font-weight:550;font-size:14px}
.admin-nav a:hover,.admin-nav a:focus-visible {background:#213f69;color:#fff;outline:none}
.admin-nav .admin-nav-warning {color:#ffd7b2}
.admin-sidebar-note {margin:22px 8px 0;font-size:12px;color:#89a6c9}
.admin-content {min-width:0}
.admin-hero {display:flex;align-items:center;justify-content:space-between;gap:20px;padding:23px 25px;border-radius:18px;background:radial-gradient(circle at 85% 20%,#285695,transparent 42%),linear-gradient(125deg,#143562,#0d2344);border:1px solid #326197}
.admin-hero h1 {font-size:clamp(23px,3vw,32px);margin:2px 0 7px}
.admin-hero form {flex:0 0 auto}
.admin-hero button {margin:0}
.admin-eyebrow {font-size:11px;letter-spacing:.12em;color:#90b8ef;margin:0}
.admin-subtitle {font-size:14px;margin:0;color:#c3d6f5}
.admin-kpis {display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:12px;margin:16px 0}
.admin-kpi {background:#142d51;border:1px solid #2a4f79;border-radius:14px;padding:16px 18px;min-width:0}
.admin-kpi span {color:#9cbae0;font-size:13px;display:block}
.admin-kpi strong {font-size:30px;display:block;margin:5px 0;font-variant-numeric:tabular-nums}
.admin-kpi em {font-style:normal;font-size:16px;color:#a5bedc}
.admin-kpi small {color:#8fa7c5}
.admin-guidance {padding:12px 16px;border-left:3px solid #5ca3f6;border-radius:8px;background:#102b4c;font-size:13px}
.admin-content > .panel {scroll-margin-top:20px;border:1px solid #2d4d75;box-shadow:0 6px 22px rgba(0,0,0,.08)}
.admin-content > .panel h2 {color:#f5faff}
.admin-success {border:1px solid #448a76;background:#153b39;color:#d9ffed;border-radius:12px;padding:14px 18px;margin:16px 0}
.admin-reset-panel {border-color:#815d48!important;background:linear-gradient(120deg,#2a2735,#18283f)!important}
.admin-reset-heading {display:flex;align-items:center;gap:13px}
.admin-reset-heading h2,.admin-reset-heading p {margin:3px 0}
.admin-reset-symbol {background:#784b42;border-radius:12px;color:#ffe5d8;font-size:28px;padding:4px 14px}
.admin-reset-button {background:#ca564d;color:#fff;font-size:16px;padding:13px 22px}
.admin-reset-button:hover {background:#ec7267}
@media(max-width:1040px){.admin-layout{grid-template-columns:195px minmax(0,1fr);gap:14px}.admin-sidebar{padding:14px 8px}.admin-kpis{grid-template-columns:repeat(2,minmax(0,1fr))}}
@media(max-width:720px){body.admin-page>main{padding:10px 12px 50px}.admin-layout{display:block}.admin-sidebar{position:static;max-height:none;margin-bottom:14px}.admin-sidebar-brand{padding-bottom:12px}.admin-sidebar-note{display:none}.admin-nav{display:flex;gap:5px;overflow-x:auto;white-space:nowrap;padding:12px 2px 0}.admin-nav a{flex:0 0 auto;padding:9px 12px}.admin-hero{padding:18px 16px;align-items:flex-start}.admin-hero h1{font-size:23px}.admin-kpi{padding:13px}.admin-kpi strong{font-size:26px}}
@media(max-width:440px){.admin-hero{flex-direction:column}.admin-kpis{gap:8px}.admin-kpi span{font-size:12px}}

/* V01.5.29: use the existing official Pingyuan emblem in the site header. */
header a.site-brand{display:inline-flex;align-items:center;gap:11px;min-height:42px}
header .site-brand-logo{width:38px;height:38px;object-fit:contain;flex:none;filter:drop-shadow(0 0 4px #15529c)}
@media(max-width:440px){header .site-brand-logo{width:32px;height:32px}header a.site-brand{gap:7px;font-size:16px}}

/* Targeted phone-watermark fullscreen fix; no media encoding or API changes. */
.player-shell .video-stage{position:relative;width:100%;aspect-ratio:16/9;max-height:82vh;overflow:hidden;background:#000}
.player-shell .video-stage video{display:block;width:100%;height:100%;max-height:82vh;aspect-ratio:16/9;object-fit:contain;border-radius:0}
.player-shell .video-stage .watermark{z-index:5;opacity:.45;text-shadow:0 1px 3px #000,0 0 5px #000;max-width:calc(100% - 8px);font-size:clamp(17px,3vw,37px)}
.player-shell:fullscreen .video-stage,.player-shell.pseudo-full .video-stage{flex:1 1 0;min-height:0;max-height:none;aspect-ratio:auto;display:flex;align-items:center;justify-content:center}
.player-shell:fullscreen .video-stage video,.player-shell.pseudo-full .video-stage video{flex:none;width:100%;height:100%;max-height:100%;min-height:0;aspect-ratio:auto;object-fit:contain}
.player-shell:fullscreen,.player-shell.pseudo-full{width:100%;height:100%;height:100dvh}
body.player-pseudo-full-active{overflow:hidden}