/* ============================================
   Login Toast Notifications
   ============================================ */
.login-toast-container {
    position: absolute;
    top: 1.5rem;
    left: 50%;
    transform: translateX(-50%);
    width: 100%;
    max-width: 26rem;
    padding: 0 1rem;
    z-index: 20;
    pointer-events: none;
}

.login-toast-container > * {
    pointer-events: auto;
}

.login-toast {
    position: relative;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0.75rem 1rem;
    margin-bottom: 0.5rem;
    border-radius: 0.625rem;
    background: var(--white-085);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border: 1px solid var(--overlay-060);
    box-shadow: 0 4px 16px var(--overlay-080);
    overflow: hidden;
    animation: toastSlideIn 0.35s cubic-bezier(0.21, 1.02, 0.73, 1);
}

.login-toast-body {
    display: flex;
    align-items: center;
    gap: 0.625rem;
    flex: 1;
    min-width: 0;
}

.login-toast-icon {
    font-size: 1.125rem;
    flex-shrink: 0;
}

.login-toast-text {
    font-size: 0.875rem;
    line-height: 1.4;
    color: var(--gray-700);
}

.login-toast-close {
    background: none;
    border: none;
    cursor: pointer;
    padding: 0.25rem;
    color: var(--gray-400);
    transition: color 0.2s;
    flex-shrink: 0;
    margin-left: 0.5rem;
}

.login-toast-close:hover {
    color: var(--gray-500);
}

/* Progress bar for auto-dismiss */
.login-toast-progress {
    position: absolute;
    bottom: 0;
    left: 0;
    height: 2px;
    width: 100%;
    transform-origin: left;
    animation: toastProgressShrink 5s linear forwards;
}

/* Type-specific colors (icon + progress bar only, background stays neutral) */
.login-toast-error .login-toast-icon {
    color: var(--danger-color);
}

.login-toast-error .login-toast-progress {
    background: var(--danger-color);
}

.login-toast-success .login-toast-icon {
    color: var(--success-color);
}

.login-toast-success .login-toast-progress {
    background: var(--success-color);
}

.login-toast-warning .login-toast-icon {
    color: var(--warning-color);
}

.login-toast-warning .login-toast-progress {
    background: var(--warning-color);
}

.login-toast-info .login-toast-icon {
    color: var(--info-color);
}

.login-toast-info .login-toast-progress {
    background: var(--info-color);
}

/* Dismiss animation */
.login-toast-dismissing {
    animation: toastSlideOut 0.3s ease forwards;
}

@keyframes toastSlideIn {
    from {
        opacity: 0;
        transform: translateY(-12px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes toastSlideOut {
    from {
        opacity: 1;
        transform: translateY(0);
    }
    to {
        opacity: 0;
        transform: translateY(-12px);
    }
}

@keyframes toastProgressShrink {
    from {
        transform: scaleX(1);
    }
    to {
        transform: scaleX(0);
    }
}

/* Responsive Design */
@media (max-width: 640px) {
    .login-container {
        padding: 1rem;
        /* 钉住实际视觉视口：vh/dvh 单位在移动端包含地址栏区域，
           会导致容器高于可见屏幕（页面可滚动、页脚下方出现空白）。
           fixed + 四边归零使容器精确等于可见区域，与地址栏状态无关。 */
        position: fixed;
        top: 0;
        right: 0;
        bottom: 0;
        left: 0;
        flex-direction: column;    /* Stack card and footer vertically */
        overflow-y: auto;          /* Content taller than viewport scrolls internally */
        overflow-x: hidden;
        height: auto;              /* Stretch via top/bottom instead of vh units */
        min-height: 0;             /* Remove vh-based min-height (fixed insets decide size) */
    }

    .login-card {
        max-width: 100%;
        max-height: none;          /* Remove height cap: container is now scrollable */
        border-radius: 16px;
        margin: auto 0;            /* Center card in remaining space (matches desktop) */
    }
    
    .login-title {
        font-size: 1.375rem;
    }
    
    .login-form {
        padding: 0.75rem 1.25rem 1.25rem;
    }
    
    .login-header {
        padding: 1.5rem 1.25rem 0.75rem;
    }

    .login-logo {
        height: 3rem;
        margin-bottom: 0.625rem;
    }

    .login-mode-switcher {
        padding: 0 1.25rem;
    }

    /* Footer on mobile: sticky-bottom via flex auto margin;
       collapses to 0 when content overflows (footer scrolls after card) */
    .login-footer-outer {
        position: relative;
        bottom: auto;
        left: auto;
        transform: none;
        margin-top: auto;
        padding-bottom: 1rem;
        max-width: 100%;
        color: rgba(0, 0, 0, 0.3);
    }

    /* Reduce background decorations on mobile */
    .login-container::before,
    .login-container::after {
        opacity: 0.5;
    }

    /* Adjust form inputs for mobile */
    .form-input {
        font-size: 1rem; /* Prevent iOS zoom on focus */
        padding: 0.625rem 2.5rem 0.625rem 2.5rem;
    }

    .form-group {
        margin-bottom: 1.25rem;
    }

    .btn-lg,
    .btn-guest-side {
        padding: 0.625rem 1rem;
        font-size: 0.9375rem;
    }
}

/* Tablet adjustments */
@media (min-width: 641px) and (max-width: 768px) {
    .login-container {
        padding: 1.5rem;
    }

    .login-card {
        max-width: 26rem;
    }
}

/* Small mobile devices */
@media (max-width: 400px) {
    .login-container {
        padding: 0.75rem;
    }

    .login-card {
        max-height: none;          /* Remove height cap: container is now scrollable */
        border-radius: 14px;
    }

    .login-title {
        font-size: 1.25rem;
    }

    .login-logo {
        height: 2.5rem;
    }

    .login-form {
        padding: 0.75rem 1rem 1rem;
    }

    .login-header {
        padding: 1.25rem 1rem 0.625rem;
    }

    .login-mode-switcher {
        padding: 0 1rem;
    }

    .form-input {
        font-size: 1rem;
    }

    .btn-lg,
    .btn-guest-side {
        padding: 0.5rem 0.875rem;
        font-size: 0.875rem;
    }

    .login-btn-row {
        gap: 0.5rem;
    }
}

/* Landscape mobile optimization */
@media (max-height: 500px) {
    .login-container {
        padding: 0.5rem;
        position: relative;        /* Override fixed: allow scrolling */
        overflow-y: auto;          /* Enable scrolling when content exceeds viewport */
        overflow-x: hidden;
        height: auto;
        min-height: 100vh;
        min-height: 100dvh;
    }

    .login-card {
        max-height: none;          /* Remove height cap: container is now scrollable */
    }

    .login-header {
        padding: 0.75rem 1.5rem 0.5rem;
    }

    .login-logo {
        height: 2.5rem;
        margin-bottom: 0.5rem;
    }

    .login-title {
        font-size: 1.25rem;
    }

    .login-subtitle {
        font-size: 0.75rem;
        margin-top: 0.25rem;
    }

    .login-form {
        padding: 0.5rem 1.5rem 1rem;
    }

    .form-group {
        margin-bottom: 0.875rem;
    }

    .login-mode-switcher {
        padding: 0 1.5rem;
    }

    .mode-btn {
        padding: 0.5rem 0.625rem;
        font-size: 0.75rem;
    }

    .btn-lg,
    .btn-guest-side {
        padding: 0.5rem 0.875rem;
        font-size: 0.875rem;
    }
}

/* ============================================
   登录模式切换器 - iOS Segmented Control
   ============================================ */
.login-mode-switcher {
    padding: 0 2rem;
    margin-bottom: 0.5rem;
}

.mode-switcher-track {
    display: flex;
    position: relative;
    background: var(--overlay-040);
    border-radius: 10px;
    padding: 3px;
}

.mode-switcher-indicator {
    position: absolute;
    top: 3px;
    left: 3px;
    width: calc(50% - 3px);
    height: calc(100% - 6px);
    background: white;
    border-radius: 8px;
    box-shadow: 0 1px 3px var(--overlay-100), 0 1px 2px var(--overlay-060);
    transition: transform 0.3s cubic-bezier(0.32, 0.72, 0, 1);
}

.mode-switcher-indicator.student-active {
    transform: translateX(100%);
}

.mode-btn {
    flex: 1;
    padding: 0.5rem 0.75rem;
    border: none;
    background: transparent;
    color: var(--gray-500);
    border-radius: 8px;
    cursor: pointer;
    font-size: 0.8125rem;
    font-weight: 500;
    transition: color 0.25s ease;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.375rem;
    position: relative;
    z-index: 1;
}

.mode-btn:hover {
    color: var(--gray-600);
}

.mode-btn-active {
    color: var(--gray-800);
    border: none;
    background: transparent;
    box-shadow: none;
}

/* ============================================
   表单帮助文本
   ============================================ */
.form-help-text {
    font-size: 0.75rem;
    color: var(--gray-400);
    margin-top: 0.375rem;
    margin-bottom: 0;
}

/* ============================================
   隐藏类
   ============================================ */
.hidden.hidden {
    display: none;
}

/* ============================================
   登录按钮行 + 游客体验并排布局
   ============================================ */
.login-btn-row {
    display: flex;
    align-items: stretch;
    gap: 0.75rem;
}

.login-btn-main {
    flex: 1;
    min-width: 0;
    line-height: 1.25;
}

.btn-guest-side {
    flex-shrink: 0;
    padding: 0.75rem 1rem;
    font-size: 0.875rem;
    font-weight: 600;
    line-height: 1.25;
    color: var(--gray-500);
    background: rgba(255, 255, 255, 0.6);
    border: 1.5px solid var(--slate-200);
    border-radius: 10px;
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    cursor: pointer;
    transition: all 0.25s ease;
    text-decoration: none;
    white-space: nowrap;
}

.btn-guest-side:hover {
    background: var(--white-090);
    border-color: var(--slate-300);
    color: var(--gray-700);
    transform: translateY(-1px);
}

.btn-guest-side:active {
    transform: translateY(0);
}

.btn-guest-side i {
    color: var(--purple-color);
    transition: color 0.2s ease;
}

.btn-guest-side:hover i {
    color: var(--purple-hover);
}