:root{--color-canvas: #f7f8fa;--color-surface: #ffffff;--color-surface-muted: #f0f1f3;--color-text: #202124;--color-text-secondary: #6b7280;--color-text-disabled: #a6abb3;--color-accent: #d93b3b;--color-accent-hover: #c83232;--color-accent-soft: #fdecec;--color-border: #e5e7eb;--color-border-strong: #cfd3d8;--color-danger: #c93636;--color-danger-soft: #fdeaea;--color-danger-border: #e3a0a0;--color-on-accent: #ffffff;color:var(--color-text);background:var(--color-canvas);font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,Segoe UI,sans-serif;font-synthesis:none;text-rendering:optimizeLegibility}*{box-sizing:border-box}body{margin:0;min-width:320px;min-height:100vh;background:var(--color-canvas)}button,input{font:inherit}button{cursor:pointer}.center-card,.player-page{width:min(100%,760px);margin:0 auto;padding:32px 20px calc(250px + env(safe-area-inset-bottom))}.player-page{padding-top:max(20px,calc(12px + env(safe-area-inset-top)))}.player-page.settings-collapsed{padding-bottom:calc(190px + env(safe-area-inset-bottom))}.center-card{min-height:100vh;display:flex;flex-direction:column;justify-content:center;gap:14px;max-width:520px}.course-home{justify-content:flex-start;padding-top:max(28px,calc(16px + env(safe-area-inset-top)))}.course-home h1{max-width:480px}.course-list{display:grid;gap:0;margin:10px 0 6px}.course-list h2{margin:0 0 2px;font-family:Georgia,Times New Roman,serif;font-size:22px}.course-group{border-bottom:1px solid var(--color-border);background:transparent}.course-group+.course-group{margin-top:14px}.course-group summary{min-height:56px;display:grid;grid-template-columns:auto minmax(0,1fr) auto;align-items:center;gap:10px;padding:6px 4px;cursor:pointer;list-style:none;border-radius:8px;transition:background-color .15s}.course-group summary::-webkit-details-marker{display:none}.course-group-icon{width:20px;height:20px;color:var(--color-accent);transition:transform .16s ease}.course-group[open] .course-group-icon{transform:rotate(180deg)}.course-group summary:hover{background:var(--color-surface-muted)}.course-group summary:focus-visible{outline:2px solid var(--color-accent);outline-offset:2px}.course-group summary span{color:var(--color-text-secondary);font-size:13px}.course-group-list{display:grid;padding:0 0 4px 28px;border-top:1px solid var(--color-border)}.course-row{display:grid;grid-template-columns:minmax(0,1fr) auto;align-items:center;gap:16px;min-height:70px;padding:10px 4px;border-bottom:1px solid var(--color-border);background:transparent;transition:background-color .15s}.course-row:last-child{border-bottom:0}.course-row:hover{background:#20212409}.course-open{min-width:0;min-height:48px;align-self:stretch;display:flex;align-items:center;padding:0;border:0;color:inherit;background:transparent;text-align:left}.course-open:focus-visible{outline:2px solid var(--color-accent);outline-offset:3px;border-radius:4px}.course-open:disabled{cursor:default}.course-copy{min-width:0;display:grid;gap:5px}.course-copy strong{line-height:1.3}.course-copy span{color:var(--color-text-secondary);font-size:13px}.download{min-width:78px;min-height:44px;display:inline-flex;align-items:center;justify-content:center;gap:6px;padding:0 8px;border:0;border-radius:10px;color:var(--color-text);background:transparent;font-weight:700;transition:background-color .15s}.download:hover:not(:disabled){color:var(--color-accent);background:var(--color-accent-soft)}.download:focus-visible{outline:2px solid var(--color-accent);outline-offset:2px}.download.downloaded{color:var(--color-accent);background:transparent}.download:disabled{cursor:default}h1{margin:4px 0 0;color:var(--color-text);font-family:Georgia,Times New Roman,serif;font-size:clamp(30px,7vw,48px);line-height:1.05}.intro,.source-note{color:var(--color-text-secondary);line-height:1.6}.source-note{font-size:13px}.primary,.secondary{min-height:52px;border-radius:14px;font-weight:750}.primary{border:0;color:var(--color-on-accent);background:var(--color-accent)}.primary:hover{background:var(--color-accent-hover)}.secondary{border:1px solid var(--color-border-strong);color:var(--color-text);background:transparent}.sample{margin-top:12px}.divider{display:flex;align-items:center;gap:12px;color:var(--color-text-secondary);font-size:13px;margin:8px 0}.divider:before,.divider:after{content:"";height:1px;flex:1;background:var(--color-border)}.file-field{display:grid;grid-template-columns:92px 1fr;align-items:center;min-height:58px;padding:10px 14px;border:1px solid var(--color-border);border-radius:14px;background:var(--color-surface)}.file-field input{position:absolute;opacity:0;pointer-events:none}.file-field strong{overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.error{padding:12px 14px;color:var(--color-danger);background:var(--color-danger-soft);border-radius:10px}.player-page header{padding-top:0}.player-page h1{font-size:clamp(26px,6vw,42px);margin:8px 0 0}.course-heading{display:flex;align-items:end;justify-content:space-between;gap:16px}.course-heading .delete{flex:none;min-height:40px;display:inline-flex;align-items:center;gap:6px;padding:0 10px;border:1px solid var(--color-danger-border);border-radius:10px;color:var(--color-danger);background:transparent;font-size:13px}.back{margin:0 0 6px;padding:0;min-height:44px;display:inline-flex;align-items:center;gap:7px;border:0;color:var(--color-text-secondary);background:transparent;font-weight:700}.back:hover{color:var(--color-accent)}.time-row{display:flex;justify-content:space-between;font-variant-numeric:tabular-nums;font-size:13px}.timeline{--timeline-progress: 0%;width:100%;height:18px;margin:0;padding:0;appearance:none;-webkit-appearance:none;background:transparent;cursor:pointer}.timeline::-webkit-slider-runnable-track{height:3px;border:0;border-radius:999px;background:linear-gradient(to right,var(--color-accent) 0 var(--timeline-progress),var(--color-border-strong) var(--timeline-progress) 100%)}.timeline::-webkit-slider-thumb{width:14px;height:14px;margin-top:-5.5px;border:0;border-radius:50%;appearance:none;-webkit-appearance:none;background:var(--color-accent);box-shadow:0 0 0 1px #e94b4b14}.timeline::-moz-range-track{height:3px;border:0;border-radius:999px;background:var(--color-border-strong)}.timeline::-moz-range-progress{height:3px;border-radius:999px;background:var(--color-accent)}.timeline::-moz-range-thumb{width:14px;height:14px;border:0;border-radius:50%;background:var(--color-accent);box-shadow:0 0 0 1px #e94b4b14}.timeline:focus-visible{outline:2px solid var(--color-accent);outline-offset:3px;border-radius:3px}.player-view-switch{width:min(100%,260px);display:grid;grid-template-columns:1fr 1fr;gap:4px;margin:22px 0 0;padding:4px;border-radius:13px;background:var(--color-surface-muted)}.player-view-switch button{min-height:44px;padding:0 14px;border:0;border-radius:10px;color:var(--color-text-secondary);background:transparent;font-weight:750}.player-view-switch button[aria-pressed=true]{color:var(--color-on-accent);background:var(--color-accent)}.focus-view{min-height:clamp(220px,calc(100dvh - 470px),520px);display:flex;align-items:center}.focus-view .focus-sentence{width:100%}.transcript-view{margin-top:22px}.focus-sentence{margin:30px 0 22px;padding:22px;border-radius:20px;border:1px solid var(--color-border);background:var(--color-surface);color:var(--color-text);box-shadow:0 14px 36px #20212414}.focus-sentence span{color:var(--color-accent);font-size:12px;font-weight:800;letter-spacing:.08em}.focus-sentence p{margin:12px 0 0;font-family:Georgia,serif;font-size:21px;line-height:1.5}.focus-sentence .focus-translation{margin-top:14px;padding-top:14px;border-top:1px solid var(--color-border);color:var(--color-text-secondary);font-family:inherit;font-size:16px;line-height:1.6}.transcript{display:grid;gap:0}.segment{width:100%;display:grid;grid-template-columns:50px 1fr;gap:10px;min-height:48px;padding:8px 12px;text-align:left;color:var(--color-text-secondary);background:transparent;border:1px solid transparent;border-radius:12px;line-height:1.35;transition:color .18s ease}.segment.active{scroll-margin-block:80px calc(210px + env(safe-area-inset-bottom))}.segment time{color:var(--color-text-secondary);font-size:12px;padding-top:3px}.segment-copy{display:grid;gap:3px}.segment-english{color:var(--color-text-secondary);transition:color .18s ease}.segment-translation{color:var(--color-text-secondary);font-size:14px;line-height:1.4}.segment.active{color:var(--color-text);background:transparent;border-color:transparent;box-shadow:none}.segment.active time{color:var(--color-accent)}.segment.active .segment-english{color:var(--color-text);font-weight:650}.segment.active .segment-translation{color:var(--color-text-secondary)}.follow-transcript{position:fixed;z-index:9;left:50%;bottom:calc(188px + env(safe-area-inset-bottom));min-height:44px;display:inline-flex;align-items:center;gap:7px;padding:0 18px;border:0;border-radius:22px;color:var(--color-on-accent);background:var(--color-accent);box-shadow:0 8px 24px #e94b4b33;transform:translate(-50%);font-weight:750}.settings-collapsed .follow-transcript{bottom:calc(140px + env(safe-area-inset-bottom))}.controls{position:fixed;z-index:10;left:0;right:0;bottom:0;padding:10px max(16px,calc((100vw - 720px)/2)) calc(10px + env(safe-area-inset-bottom));background:#fffffff0;border-top:1px solid var(--color-border);-webkit-backdrop-filter:blur(18px);backdrop-filter:blur(18px)}.player-settings{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));max-width:720px;margin:0 auto}.player-settings[hidden]{display:none}.player-setting{position:relative;min-width:0}.setting-trigger{width:100%;min-height:48px;display:grid;place-content:center;gap:2px;padding:3px 6px;border:0;border-radius:10px;color:var(--color-text-secondary);background:transparent;text-align:center}.setting-trigger:hover,.setting-trigger[aria-expanded=true]{background:var(--color-surface-muted)}.setting-trigger:disabled{color:var(--color-text-disabled);cursor:default}.setting-trigger strong{color:var(--color-text);font-size:14px;font-variant-numeric:tabular-nums}.setting-trigger:disabled strong{color:inherit;font-size:12px}.setting-trigger span{font-size:12px}.player-menu{position:absolute;z-index:20;bottom:calc(100% + 10px);width:210px;max-height:min(360px,calc(100vh - 220px));overflow-y:auto;padding:8px;border:1px solid var(--color-border);border-radius:14px;background:var(--color-surface);box-shadow:0 16px 40px #20212429}.speed-menu{left:0}.repeat-menu{left:50%;width:286px;transform:translate(-50%)}.reading-menu{right:0}.menu-title{display:block;padding:5px 7px 9px;color:var(--color-text-secondary);font-size:12px;font-weight:750}.menu-option{width:100%;min-height:42px;display:grid;grid-template-columns:24px 1fr;align-items:center;padding:0 10px;border:0;border-radius:9px;color:var(--color-text);background:transparent;text-align:left}.icon-slot{width:18px;height:18px;display:grid;place-items:center}.icon-slot svg{width:18px;height:18px}.menu-option.selected,.repeat-grid .selected{color:var(--color-on-accent);background:var(--color-accent)}.menu-option:disabled{color:var(--color-text-disabled);cursor:default}.repeat-grid{display:grid;grid-template-columns:repeat(5,1fr);gap:6px;margin-bottom:8px}.repeat-grid button{min-width:0;min-height:42px;padding:0;border:0;border-radius:9px;color:var(--color-text);background:var(--color-surface-muted);font-size:13px;font-variant-numeric:tabular-nums}.repeat-grid button svg{width:14px;height:14px;margin-right:2px;vertical-align:-2px}.repeat-off{margin-top:4px;border-top:1px solid var(--color-border);border-radius:0 0 9px 9px}.player-progress{max-width:720px;margin:6px auto 0}.player-progress .timeline{display:block}.player-progress .time-row{margin-top:-2px}.main-controls{width:min(100%,360px);display:grid;grid-template-columns:48px 48px 60px 48px 48px;align-items:center;justify-content:space-between;margin:5px auto 0}.main-controls button{width:48px;height:48px;border:0;border-radius:50%;color:var(--color-text);background:var(--color-surface-muted);font-weight:800}.main-controls button svg{width:22px;height:22px;display:block;margin:auto}.main-controls .play{width:60px;height:60px;color:var(--color-on-accent);background:var(--color-accent)}.main-controls .play:hover{background:var(--color-accent-hover)}.main-controls .play svg{width:24px;height:24px}.main-controls .settings-toggle svg{width:23px;height:23px}.button-icon{width:18px;height:18px;flex:none}.loading-icon{animation:icon-spin .8s linear infinite}@keyframes icon-spin{to{transform:rotate(360deg)}}@media(max-width:420px){.center-card,.player-page{padding-left:16px;padding-right:16px}.course-heading{align-items:start;flex-direction:column;gap:10px}.setting-trigger{padding-left:2px;padding-right:2px}.setting-trigger strong{font-size:13px}.setting-trigger span{font-size:11px}.repeat-menu{width:300%}.course-group-list{padding-left:24px}.course-row{align-items:center;gap:10px}.download{min-width:72px;padding:0 6px}}@media(prefers-reduced-motion:reduce){*,*:before,*:after{scroll-behavior:auto!important}.course-group-icon{transition:none}.loading-icon{animation-duration:1.6s}}