*,:before,:after{box-sizing:border-box;margin:0;padding:0}:root{--font:-apple-system,BlinkMacSystemFont,"SF Pro Display","SF Pro Text","Helvetica Neue","Noto Sans JP",sans-serif;--black:#1d1d1f;--gray-1:#86868b;--gray-2:#d2d2d7;--gray-3:#f5f5f7;--white:#fff;--blue:#0071e3;--blue-hover:#0077ed;--green:#30d158;--red:#ff3b30;--orange:#ff9f0a;--radius:16px;--radius-sm:12px;--radius-xs:8px;--transition:.3s cubic-bezier(.25,.1,.25,1)}body{font-family:var(--font);background:var(--white);color:var(--black);-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale;line-height:1.5}.app-nav{-webkit-backdrop-filter:blur(20px);z-index:100;background:#ffffffeb;border-bottom:1px solid #0000000f;justify-content:space-between;align-items:center;height:52px;padding:0 28px;display:flex;position:sticky;top:0}.app-nav-brand{color:var(--black);letter-spacing:-.01em;font-size:15px;font-weight:600}.app-nav-right{color:var(--gray-1);align-items:center;gap:16px;font-size:13px;display:flex}.app-nav-user{color:var(--black);font-weight:500}.app-nav-logout{color:var(--blue);cursor:pointer;font-size:13px;font-weight:500;font-family:var(--font);background:0 0;border:none}.app-nav-logout:hover{text-decoration:underline}.login-screen{flex-direction:column;justify-content:center;align-items:center;min-height:100vh;padding:60px 40px;display:flex}.login-logo{flex-direction:column;align-items:center;margin-bottom:8px;display:flex}.login-logo-main{letter-spacing:-.04em;color:var(--black);font-size:36px;font-weight:800;line-height:1}.login-logo-sub{letter-spacing:.28em;color:var(--gray-1);text-transform:uppercase;margin-top:6px;font-size:11px;font-weight:600}.login-subtitle{color:var(--gray-1);letter-spacing:-.01em;margin-bottom:48px;font-size:17px;font-weight:400}.login-form{width:100%;max-width:360px}.input-group{margin-bottom:20px}.input-label{color:var(--black);margin-bottom:6px;font-size:13px;font-weight:500;display:block}.input-field{width:100%;font-size:17px;font-family:var(--font);border:1px solid var(--gray-2);border-radius:var(--radius-sm);background:var(--gray-3);color:var(--black);transition:var(--transition);letter-spacing:.1em;text-align:center;outline:none;padding:14px 16px}.input-field:focus{border-color:var(--blue);background:var(--white);box-shadow:0 0 0 4px #0071e31a}.input-field::placeholder{color:var(--gray-2);letter-spacing:0;font-size:15px}.input-hint{color:var(--gray-1);margin-top:6px;font-size:12px}.login-btn{background:var(--blue);width:100%;color:var(--white);border-radius:var(--radius-sm);font-size:17px;font-weight:500;font-family:var(--font);cursor:pointer;transition:var(--transition);letter-spacing:-.01em;border:none;margin-top:8px;padding:14px}.login-btn:hover{background:var(--blue-hover)}.login-btn:disabled{opacity:.6;cursor:not-allowed}.login-footer{color:var(--gray-1);margin-top:40px;font-size:12px}.login-error{border-radius:var(--radius-xs);color:var(--red);text-align:center;background:#fef2f2;margin-top:20px;padding:12px 16px;font-size:14px}.login-info{border-radius:var(--radius-xs);color:#92400e;text-align:center;background:#fffbeb;justify-content:center;align-items:center;gap:8px;margin-bottom:24px;padding:12px 20px;font-size:14px;display:flex}.date-header{text-align:center;padding:48px 28px 32px}.date-day{letter-spacing:-.04em;color:var(--black);font-size:48px;font-weight:700;line-height:1}.date-meta{color:var(--gray-1);letter-spacing:-.01em;margin-top:4px;font-size:20px;font-weight:400}.date-count{color:var(--gray-1);margin-top:16px;font-size:14px}.date-count strong{color:var(--black);font-weight:600}.lessons-container{max-width:640px;margin:0 auto;padding:0 28px 40px}.lesson-card{background:var(--gray-3);border-radius:var(--radius);transition:var(--transition);margin-bottom:12px;padding:24px;list-style:none}.lesson-card:hover{background:#ebebf0}.lesson-time{color:var(--gray-1);align-items:center;gap:6px;margin-bottom:4px;font-size:13px;font-weight:500;display:flex}.lesson-dot{background:var(--green);border-radius:50%;flex-shrink:0;width:6px;height:6px;display:inline-block}.lesson-dot.no-url{background:var(--orange)}.lesson-student{letter-spacing:-.02em;color:var(--black);margin-bottom:12px;font-size:22px;font-weight:600}.lesson-bottom{justify-content:space-between;align-items:center;display:flex}.lesson-id{color:var(--gray-1);font-size:12px}.lesson-start-btn{background:var(--blue);color:var(--white);font-size:15px;font-weight:500;font-family:var(--font);cursor:pointer;transition:var(--transition);letter-spacing:-.01em;border:none;border-radius:980px;align-items:center;gap:8px;padding:10px 24px;text-decoration:none;display:inline-flex}.lesson-start-btn:hover{background:var(--blue-hover);transform:scale(1.02)}.lesson-no-url{color:var(--orange);align-items:center;gap:6px;font-size:13px;display:flex}.lesson-card.no-url{opacity:.6}.empty-state{text-align:center;padding:80px 28px}.empty-icon{color:var(--gray-2);margin-bottom:20px;font-size:56px}.empty-title{color:var(--black);letter-spacing:-.02em;margin-bottom:8px;font-size:22px;font-weight:600}.empty-desc{color:var(--gray-1);max-width:320px;margin:0 auto;font-size:15px}.error-state{text-align:center;padding:80px 28px}.error-icon{width:48px;height:48px;color:var(--red);background:#fef2f2;border-radius:50%;justify-content:center;align-items:center;margin:0 auto 20px;font-size:24px;display:flex}.error-title{color:var(--black);letter-spacing:-.02em;margin-bottom:8px;font-size:20px;font-weight:600}.error-desc{color:var(--gray-1);margin-bottom:24px;font-size:15px}.error-retry{background:var(--gray-3);color:var(--black);font-size:15px;font-weight:500;font-family:var(--font);cursor:pointer;transition:var(--transition);border:none;border-radius:980px;align-items:center;gap:6px;padding:10px 20px;display:inline-flex}.error-retry:hover{background:var(--gray-2)}@media (max-width:768px){.date-day{font-size:36px}.date-meta{font-size:17px}.lesson-student{font-size:19px}.login-screen{padding:40px 24px}.lessons-container{padding:0 16px 40px}}