:root{font-family:Inter,system-ui,Avenir,Helvetica,Arial,sans-serif;line-height:1.5;font-weight:400;color-scheme:light dark;color:#ffffffde;background-color:#242424;font-synthesis:none;text-rendering:optimizeLegibility;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale}body{margin:0;min-width:320px;min-height:100vh}h1{font-size:3.2em;line-height:1.1}button{border-radius:8px;border:1px solid transparent;padding:.6em 1.2em;font-size:1em;font-weight:500;font-family:inherit;background-color:#1a1a1a;cursor:pointer;transition:border-color .25s}button:hover{border-color:#646cff}button:focus,button:focus-visible{outline:4px auto -webkit-focus-ring-color}:root{--student-bg: #f8fafc;--student-text: #111827;--sidebar-bg: #0f172a;--sidebar-hover: #1e293b;--sidebar-text: #e2e8f0;--sidebar-active-bg: rgba(59, 130, 246, .15);--sidebar-active-text: #60a5fa;--student-card: #ffffff;--student-border: #e2e8f0}body{background-color:var(--student-bg);color:var(--student-text);margin:0;font-family:Inter,sans-serif}.app-shell{display:flex;min-height:100vh}.sidebar{width:260px;background:var(--sidebar-bg);color:var(--sidebar-text);display:flex;flex-direction:column;border-right:1px solid var(--student-border);position:fixed;top:0;bottom:0;left:0;z-index:1000;transition:transform .3s ease}.main-content{margin-left:260px;flex:1;padding:32px;width:100%;box-sizing:border-box}.mobile-topbar{display:none}.exercise-card-content{display:flex;align-items:stretch;gap:24px}.video-container{width:180px;height:240px;border-radius:12px;overflow:hidden;background:#000;flex-shrink:0;position:relative;box-shadow:0 4px 12px #0003}.frequency-scroll{display:flex;justify-content:space-between;align-items:center;position:relative;margin-top:12px;width:100%}.mobile-stack{display:flex;justify-content:space-between;align-items:flex-end}.login-logo-img{max-width:480px}.login-card{margin-top:-130px}@media (max-width: 768px){.app-shell{display:block}.sidebar{transform:translate(-100%);width:280px;box-shadow:4px 0 16px #0003}.sidebar.open{transform:translate(0)}.main-content{margin-left:0;padding:80px 16px 16px}.mobile-topbar{display:flex;align-items:center;justify-content:space-between;position:fixed;top:0;left:0;right:0;height:64px;background:#fff;padding:0 16px;border-bottom:1px solid var(--student-border);z-index:900;box-shadow:0 2px 4px #0000000d}h1{font-size:1.5rem!important}h2{font-size:1.25rem!important}.table-container{overflow-x:auto;-webkit-overflow-scrolling:touch}.exercise-card-content{flex-direction:column-reverse}.video-container{width:100%!important;height:auto!important;aspect-ratio:16/9;max-height:300px}.frequency-scroll{overflow-x:visible;padding-bottom:0;justify-content:space-between;gap:2px}.frequency-scroll>div{min-width:auto;flex:1}.timer-display{font-size:2.5rem!important}.mobile-stack{flex-direction:column;align-items:flex-start!important;gap:16px}.mobile-stack>div:last-child{text-align:left!important}.login-logo-img{max-width:320px!important}.login-card{margin-top:-60px!important;padding:24px!important}}.sidebar-overlay{position:fixed;top:0;right:0;bottom:0;left:0;background:#00000080;z-index:999;-webkit-backdrop-filter:blur(2px);backdrop-filter:blur(2px)}